Unlike some pretty metal plants that thrive in the darkness, yeast generally doesn’t function well in the light. This fungi turns carbohydrates into ingredients for beer or bread when left to ferment in the dark. It must be stored in dark dry places, as exposure to light can keep fermentation from happening all together. However, a group of scientists have engineered a strain of yeast that may actually work better with light that could give these fungi an evolutionary boost in a simple way. The findings are described in a study published January 12 in the journal Current Biology.

[Related: The key to tastier beer might be mutant yeast—with notes of banana.]

“We were frankly shocked by how simple it was to turn the yeast into phototrophs (organisms that can harness and use energy from light),” study co-author and Georgia Institute of Technology cellular biologist Anthony Burnetti said in a statement. “All we needed to do was move a single gene, and they grew 2 percent faster in the light than in the dark. Without any fine-tuning or careful coaxing, it just worked.”

Giving yeast such an evolutionarily important trait may help us understand how phototropism originated and how it can be used to study evolution and biofuel production, as well as how cells age. 

Give it some energy

Previous work on the evolution of multicellular life by this research group inspired the new study. In 2023, the group uncovered how a single-celled model organism called snowflake yeast could evolve multicellularity over 3,000 generations. However, one of the major limitations to their evolution experiments was a lack of energy.

“Oxygen has a hard time diffusing deep into tissues, and you get tissues without the ability to get energy as a result,” said Burnetti. “I was looking for ways to get around this oxygen-based energy limitation.”

Light is one of the ways organisms can get an energy boost without oxygen. However, from an evolutionary standpoint, an organism’s ability to turn light into usable energy can be complicated. The molecular machinery that allows plants to use light for energy requires numerous proteins and genes that are difficult to synthesize and transfer into other organisms. This is difficult in the lab and through natural processes like evolution. 

A simple rhodopsin

Plants are not the only organisms that can convert light into energy. Some on-plant organisms can also use this light with the help of rhodopsins. These proteins can convert light into energy without any extra cellular machinery.

“Rhodopsins are found all over the tree of life and apparently are acquired by organisms obtaining genes from each other over evolutionary time,” study co-author and Georgia Tech Ph.D. student Autumn Peterson said in a statement. 

[Related: Scientists create a small, allegedly delicious piece of yeast-free pizza dough.]

A genetic exchange like this is called a horizontal gene transfer, where genetic information is shared between organisms that are not closely related. A horizontal gene transfer can cause large evolutionary leaps in a short period of time. One example of this is how bacteria can quickly develop resistance to certain antibiotics. This can happen with all kinds of genetic information and is particularly common with rhodopsin proteins.

“In the process of figuring out a way to get rhodopsins into multi-celled yeast,” said Burnetti, “we found we could learn about horizontal transfer of rhodopsins that has occurred across evolution in the past by transferring it into regular, single-celled yeast where it has never been before.”

Under the spotlight

To see if they could give a single-celled organism a solar-powered rhodopsin, the team added a rhodopsin gene synthesized from a parasitic fungus to common baker’s yeast. This individual gene is coded for a form of rhodopsin that would be inserted into the cell’s vacuole. This is a part of the cell that can turn chemical gradients made by proteins like rhodopsin into needed energy. 

With this vacuolar rhodopsin, the yeast grew roughly 2 percent faster when it was exposed to light. According to the team, this is a major evolutionary benefit and the ease that the rhodopsins can spread across multiple lineages might be key. 

“Here we have a single gene, and we’re just yanking it across contexts into a lineage that’s never been a phototroph before, and it just works,” said Burnetti. “This says that it really is that easy for this kind of a system, at least sometimes, to do its job in a new organism.”

Yeasts that function better in the light could also increase its shelf life. Vacuolar function may also contribute to cellular aging, so this group has started collaborating with other teams to study how rhodopsins may reduce aging effects in the yeast. Similar solar-powered yeast is also being studied to advance biofuels. The team also hopes to study how phototrophy changes yeast’s evolutionary journey to a multicellular organism. 

The post This yeast loves light appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Beginning about 2.6 million years ago, giant primates almost 10 feet tall weighing 551 pounds roamed the plains of southern China. Gigantopithecus blacki (G. blacki) towered over today’s largest monkeys by about five feet and is believed to be the largest primate to ever roam the Earth. However, it went extinct just as other primates–like orangutans–were thriving. 

[Related: These primate ancestors were totally chill with a colder climate.]

Now, a team of scientists from China, Australia, and the United States believe that this giant ape went extinct between 295,000 and 215,000 years ago because it could not adapt its food preferences and behaviors and was vulnerable to extreme changes in the planet’s climate. The findings are detailed in a study published January 10 in the journal Nature. 

“The story of G. blacki is an enigma in paleontology–how could such a mighty creature go extinct at a time when other primates were adapting and surviving? The unresolved cause of its disappearance has become the Holy Grail in this discipline,” Yingqi Zhang, study co-author and Institute of Vertebrate Palaeontology and Palaeoanthropology at the Chinese Academy of Sciences (IVPP) paleontologist, said in a statement. 

Seasonal shifts 

Roughly 700,000 to 600,000 years ago, the rich forest environment that G. blacki lived in began to change. The new study proposes that as Earth’s four seasons began to strengthen and G. blacki’s habitat saw more variability in temperature and precipitation, the structure of these forest communities began to change. 

In response, G. blacki’s close relatives the orangutans adapted their habitat preferences, behavior, and size over time. However, G. blacki was not quite as nimble. Based on its dental anatomy, these giant apes were herbivores that had adapted to eat fibrous foods like fruits. However, when its favorite food sources were not available, the team believes that G. blacki relied on a less nutritious backup source of sustenance, decreasing the diversity of its food. They likely suffered from a reduced geographic range for foraging, became less mobile, and saw chronic stress and dwindling numbers. 

“G. blacki was the ultimate specialist, compared to the more agile adapters like orangutans,  and this ultimately led to its demise,” said Zhang. 

Honing in on a date

G. blacki left behind roughly 2,000 fossilized teeth and four jawbones that helped paleontologists put together the story of G. blacki’s time on Earth, but more precise dating of these remains was needed to determine its extinction story. To find definitive evidence of their extinction, the team took on a large-scale project that explored 22 cave sites in a wide region of Guangxi Province in southern China. 

[Related: Nice chimps finish last—so why aren’t all of them mean?]

Determining the exact time when a species disappears from the fossil record helps paleontologists determine a timeframe that they can work to rebuild from other evidence. 

“Without robust dating, you are simply looking for clues in the wrong places,” Kira Westaway, a study co-author and geochronologist at Macquarie University in Australia, said in a statement

In the study, the team used six dating techniques the samples of cave sediments and teeth fossils. The techniques produced 157 radiometric ages that were combined with eight sources of environmental and behavioral evidence. They took this combined figure and applied it to 11 caves that had evidence of G blacki in them and 11 caves of a similar age range that did not have any remains of G. blacki.

The primary technique that helped the team hone in on a date range was luminescence dating. It measures a light-sensitive signal that is found in the burial sediments that encased the G. blacki fossils. Uranium series and electron-spin resonance were also critical in dating the G. blacki teeth themselves. 

“By direct-dating the fossil remains, we confirmed their age aligns with the luminescence sequence in the sediments where they were found, giving us a comprehensive and reliable chronology for the extinction of G. blacki,” Renaud Joannes-Boyau, a study co-author and geochronologist at Southern Cross University  in Australia, said in a statement. 

Building a world from teeth and pollen 

Researchers also used a detailed pollen analysis to reconstruct what the plant life looked like hundreds of thousands of years ago, a stable isotope analysis of the teeth, and a detailed analysis of the cave sediments to re-create the environmental conditions leading up to the time G blacki went extinct. Trace element and dental microwear textural analysis of the apes’ teeth enabled the team to model what G. blacki’s behavior likely looked like when they were flourishing, compared to their demise. 

[Related: An ‘ancestral bottleneck’ took out nearly 99 percent of the human population 800,000 years ago.]

“Teeth provide a staggering insight into the behavior of the species indicating stress, diversity of food sources, and repeated behaviors,” said Joannes-Boyau.

The dates of the fossils combined with the pollen and teeth analysis revealed that G.blacki went extinct between 295,000 and 215,000 years ago, earlier than scientists previously assumed. The team believes that studying their lack of adaptation has implications for today’s changing climate and the need for adaptation. 

“With the threat of a sixth mass extinction event looming over us, there is an urgent need to understand why species go extinct,” said Westaway. “Exploring the reasons for past unresolved extinctions gives us a good starting point to understand primate resilience and the fate of other large animals, in the past and future.”

The post These extinct, nearly 10-foot-tall apes could not adapt to shifting seasons appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Some fruit bats eat up to twice their body weight in sugary mangoes, bananas, or figs every day to not only survive, but thrive. Unlike humans, these flying mammals can have an essentially permanent sweet tooth and do not develop some of the negative health consequences such as diabetes. A study published January 9 in the journal Nature Communications found that genetic adaptations have helped keep their sugary diets from becoming harmful. 

[Related: How do bats stay cancer-free? The answer could be lifesaving for humans.]

The study could have future implications for treating diabetes, which affects an estimated 38 million Americans, according to the Centers for Disease Control and Prevention (CDC). It is the eighth leading cause of death in the United States and the leading cause of kidney failure, lower-limb amputations, and adult blindness.

“With diabetes, the human body can’t produce or detect insulin, leading to problems controlling blood sugar,” study co-author and University of California, San Francisco geneticist Nadav Ahituv said in a statement. “But fruit bats have a genetic system that controls blood sugar without fail. We’d like to learn from that system to make better insulin-or sugar-sensing therapies for people.”  

Fruit bats vs. insect bats

Every day, fruit bats wake up after about 20 hours of sleep and feast on fruit before returning back to their caves, trees, or human-built structures to roost. To figure out how they can eat so much sugar and thrive, the team in this study focused on how the bat pancreas and kidneys evolved. The pancreas is an abdominal organ that controls blood sugar. 

Researchers compared the Jamaican fruit bat with an insect-eating bat called the big brown bat. They analyzed the gene expression–which genes were switched on or off–and regulatory DNA that controls gene expression. To do this, the team measured both the gene expression and regulatory DNA present in individual cells. These measurements show which types of cells primarily make up the bat’s organs and also how these cells regulate the gene expression that manages their diet. 

They found that the compositions of the pancreas and kidneys in fruit bats evolved to accommodate their sugary diet. The pancreas had more cells to produce insulin, an essential hormone that tells the body to lower blood sugar. It also had more cells that produce another sugar-regulating hormone called glucagon. The fruit bat kidneys had more cells to trap scarce salts and electrolytes as they filter blood.  

Changes in DNA

Taking a closer look at the genetics behind this, the team saw that the regulatory DNA in those cells had evolved to switch the appropriate genes for fruit metabolism on or off. The insect-eating big brown bats had more cells that break down protein and conserve water and the gene expression in these cells was calibrated to handle a diet of bugs. 

[Related: Vampire bats socially distance when they feel sick.]

“The organization of the DNA around the insulin and glucagon genes was very clearly different between the two bat species,” study co-author and Menlo College biologist Wei Gordon said in a statement. “The DNA around genes used to be considered ‘junk,’ but our data shows that this regulatory DNA likely helps fruit bats react to sudden increases or decreases in blood sugar.” 

While some of the fruit bat’s biology resembled what is found in humans with diabetes, the bats are not known to have the same health effects.

“Even small changes, to single letters of DNA, make this diet viable for fruit bats,” said Gordon. “We need to understand high-sugar metabolism like this to make progress helping the one in three Americans who are prediabetic.” 

Studying bats for human health

Bats are one of the most diverse families of mammals and everything from their immune systems to very particular diets are considered by some scientists to be examples of evolutionary triumph. This study is one of recent examples of how studying bats could have implications for human health, including in cancer research and virus prevention. 

For this study, Gordon and Ahituv traveled to Belize to participate in an annual Bat-a-Thon, where they took census of wild bats and field samples. One of the Jamaican fruit bats that they captured at the Bat-a-Thon was used to study sugar metabolism.  

“For me, bats are like superheroes, each one with an amazing super power, whether it is echolocation, flying, blood sucking without coagulation, or eating fruit and not getting diabetes,” Ahituv said. “This kind of work is just the beginning.” 

The post Why fruit bats can eat tons of sugar without getting diabetes appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

The nearly half a billion year old remains of some enormous and extinct carnivorous worms have been discovered near the top of the world by an international team of researchers. The ancient creature named Timorebestia, or ‘terror beasts’ in Latin, lived in the water column of North Greenland over 518 million years ago. The new fossils indicate that the worms had fins on the sides of their bodies, a head with a long antenna, and enormous jaw structures on the insides of their mouth. They could grow to almost 12 inches long. These were some of the largest swimming animals of the Early Cambrian period and are described in a study published January 3 in the journal Science Advances.

[Related: A three-eyed organism roamed the seas half a billion years ago.]

An ‘explosion’ of life

When these terror beasts were alive over 500 million years ago, the Earth was undergoing a major expansion of life called the Cambrian Explosion. This is when most major groups of animals first appear in the fossil record, partially due to cooler temperatures and tectonic changes. All of this biological diversification also occurred in a relatively short period of time–in about 30 million years. 

The Timorebestia fossils were found during a 2017 expedition to the Early Cambrian Sirius Passet fossil locality in a very remote section of North Greenland. Timorebestia may be some of the earliest carnivorous animals to have colonized the water column here and reveal a past potential dynasty of predators that were previously unknown to scientists. Early arthropods were known to be the dominant predators during the Cambrian period, including some “weird shrimp from Canada” called anomalocaridids.

“Our research shows that these ancient ocean ecosystems were fairly complex with a food chain that allowed for several tiers of predators,” study co-author and University of Bristol paleontologist Jakob Vinther said in a statement. “Timorebestia were giants of their day and would have been close to the top of the food chain. That makes it equivalent in importance to some of the top carnivores in modern oceans, such as sharks and seals back in the Cambrian period.”

Timorebestia is also a distant but close relative of living arrow worms called chaetognaths. These worms are much smaller than today’s enormous ocean predators and only eat zooplankton, a far cry from their apex predator days of the past.

Opening a 518 million-year old digestive system 

The fossils from the Sirius Passet were exceptionally well preserved so the team was able to study the remains of their muscle anatomy, nervous systems, and digestive systems very closely. When they looked inside Timorebestia’s fossilized digestive system, they found the remains of a common, swimming arthropod called Isoxys. 

“We can see these arthropods was a food source [for] many other animals,” study co-author and University of Bristol paleontologist Morten Lunde Nielsen said in a statement. “They are very common at Sirius Passet and had long protective spines, pointing both forwards and backwards. However, they clearly didn’t completely succeed in avoiding that fate, because Timorebestia munched on them in great quantities.”

While arthropods like Isoxys appear in the fossil record about 521 to 529 million years ago, modern living arrow worms can be traced back at least 538 million years. Since arrow worms and these more early Timorebestia were swimming predators, the team believes that they dominated the oceans before arthropods took off. Their dynasty may have lasted about 10 to 15 million years before they were superseded by other groups of marine predators. 

Jaw predator evolution

The discovery of Timorebestia is also helping paleontologists understand where jawed predators came from. The arrow worms living today have bristles on their heads for catching prey, instead of having jaws inside of its head like Timorebestia. By comparison, today’s microscopic jaw worms have an oral setup that is more similar to Timorebestia, so arrow worms and jaw worms likely shared an ancestor over half a billion years ago.Timorebestia and some of the other specimens that the team found on this expedition are revealing the evolutionary links between organisms that may look different, but are closely related. It is also helping paint a better picture of how arrow worms evolved over hundreds of millions of years. 

[Related: A 500-million-year-old sea squirt is the evolutionary clue we need to understand our humble beginnings.]

“Living arrow worms have a distinct nervous center on their belly, called a ventral ganglion. It is entirely unique to these animals,” study co-author and Korean Polar Research Institute paleontologist Tae Yoon Park said in a statement. “We have found this preserved in Timorebestia and another fossil called Amiskwia. People have debated whether or not Amiskwia was closely related to arrow worms, as part of their evolutionary stem lineage. The preservation of these unique ventral ganglia gives us a great deal more confidence in this hypothesis.”

The team collected a wide variety of organisms during the expedition and plan to continue to study these specimens to learn more about how the planet’s earliest animal ecosystems evolved. 

The post Extinct ‘terror beasts’ were some pretty formidable worms appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Frogs are well known for their sticky, whip-like tongues, lumpy warts, and the colorful, poisonous skin covering some species. One group of frogs in Southeast Asia has another distinguishing feature–fangs. Scientists recently discovered a new species of fanged frog that uses these bony jaws jutting out of their lower jawbone to fight with other frogs and hunt shelled prey like giant centipedes and crabs. Limnonectes phyllofolia is also the smallest known species of fanged frog and is described in a study published December 20 in the journal PLOS ONE.

[Related: Female frogs appear to play dead to avoid mating.]

“This new species is tiny compared to other fanged frogs on the island where it was found, about the size of a quarter,” study co-author and biologist Jeff Frederick said in a statement. “Many frogs in this genus are giant, weighing up to two pounds. At the large end, this new species weighs about the same as a dime.” Frederick is a postdoctoral researcher at the Field Museum in Chicago and conducted this research as a doctoral candidate at the University of California, Berkeley.

The frogs were found on the mountainous island of Sulawesi in Indonesia. It’s a large 71,898 square mile-long island with a large network of volcanoes, mountains, lowland rainforest, and cloud forests in the mountains.

“The presence of all these different habitats mean that the magnitude of biodiversity across many plants and animals we find there is unreal—rivaling places like the Amazon,” said Frederick.

Members of a joint United States-Indonesia amphibian and reptile research team noticed something surprising on the leaves of tree saplings and moss-covered boulders in the jungle–frog eggs.

Frogs lay eggs covered by a jelly-like substance instead of a hard and protective shell like a bird. To keep them from drying out, most amphibians will lay their eggs in water. Instead, these frogs left their egg masses on leaves and mossy boulders above the ground. After finding these nests, the team began to see the small, brown frogs. 

“Normally when we’re looking for frogs, we’re scanning the margins of stream banks or wading through streams to spot them directly in the water,” Frederick says. “After repeatedly monitoring the nests though, the team started to find attending frogs sitting on leaves hugging their little nests.” 

The close contact with the eggs allows the adults to coat them with the right compounds to keep them moist and safe from bacterial and fungal contamination. They were named Limnonectes phyllofolia, which translates to “leaf-nester.”

[Related: Go (virtually) adopt an axolotl, the ‘Peter Pan’ of amphibians.]

The frogs who laid these eggs on leaves and boulders were tiny members of the fanged frog family. The caretakers of the nests were all males. According to Frederick, egg-guarding behavior from male frogs is uncommon, but not unheard of. The team theorizes that the frogs’ unusual reproductive behaviors may also relate back to their smaller fangs. While some of their relatives have larger fangs that help them ward off competition, these frogs likely evolved a way to lay their eggs away from the water and lost the need for such big fangs. 

“It’s fascinating that on every subsequent expedition to Sulawesi, we’re still discovering new and diverse reproductive modes,” says Frederick. “Our findings also underscore the importance of conserving these very special tropical habitats. Most of the animals that live in places like Sulawesi are quite unique, and habitat destruction is an ever-looming conservation issue for preserving the hyper-diversity of species we find there. Learning about animals like these frogs that are found nowhere else on Earth helps make the case for protecting these valuable ecosystems.”

The post This tiny ‘leaf-nester’ is the smallest known fanged frog appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

To survive the dark and snowy Arctic winters, reindeer have evolved unique visual systems. Their eyes change color to adjust to the huge swings in sunlight between Arctic summer and winter, but may do even more to help them forage. A study published December 15 in the journal i-Perception found that their eyes may have evolved to see light in the ultraviolet spectrum to help them find their favorite food in their desolate  home.

[Related: Jackrabbit’s color-changing fur may prepare them for climate change.]

Reindeer primarily eat Cladonia rangiferina (C. rangiferina), which is appropriately nicknamed reindeer moss. This plant is not a moss, but a species of algae-fungus called lichen. It forms a thick and crunchy blanket on the ground across the Earth’s northern latitudes and helps play an important role in the ecosystem as a food source. 

In the study, the team worked in the Cairngorms mountains in the Scottish Highlands, home to Britain’s only reindeer herd. Reindeer were locally hunted to extinction, but began to be reintroduced from Scandinavia in 1952. The Cairngorms are home to more than 1,500 species of lichen, but the reindeer here only rely on C. rangiferina during the winter months

“A peculiar trait of reindeer is their reliance on this one type of lichen,”  study co-author and Dartmouth College anthropologist and evolutionary biologist Nathaniel Dominy said in a statement. “It’s unusual for any animal to subsist so heavily on lichens, let alone such a large mammal.”

When up against snow, the white lichen is invisible to the human eye.. However, co-authors Catherine Hobaiter and Julie Harris from the University of St. Andrews found that C. rangiferina and some other lichen species that supplement the reindeer diet absorb ultraviolet (UV) light. The team used spectral data from the lichen and light filters that were made to mimic reindeer vision and found that the plants may look like dark patches against a bright landscape to the reindeer. They stand out like Dalmatian spots and are easier for the reindeer to locate.

According to Dominy, this is one of the first studies to use a visual approximation of how these mammals may see their world. 

“If you can put yourself in their hooves looking at this white landscape, you would want a direct route to your food,” Dominy said. “Reindeer don’t want to waste energy wandering around searching for food in a cold, barren environment. If they can see lichens from a distance, that gives them a big advantage, letting them conserve precious calories at a time when food is scarce.”

Some animals that can see on the UV spectrum include dogs, cats, pigs, and even ferrets. They generally do this with the short blue photoreceptors called cones present in their eyes. 

Earlier studies have shown that reindeer eyes change from golden in the summer and a vivid blue in the winter. The light-enhancing membrane that gives many animals a shiny eye called the tapetum transitions every season. The blue hue of their eyes is believed to amplify the low levels of sunlight present during polar winters. 

[Related: How do animals see the world?]

“If the color of the light in the environment is primarily blue, then it makes sense for the eye to enhance the color blue to make sure a reindeer’s photoreceptors are maximizing those wavelengths,” Dominy says.

However, the blue tapetum also lets up to 60 percent of UV light pass through to the eye’s color sensors. The reindeer likely see the winter world as a shade of purple the way a human may see a room with a black light. Snow and other UV-reflecting surfaces then shine brightly while surfaces that absorb UV light are dark.

Scientists have investigated why an Arctic animal that is active during the day would have eyes that are so receptive to UV light that reflects off of the snow. This study suggests that the answer to this question is tied to C. rangiferina and other lichens, since UV light doesn’t reflect from those organisms. The team believes that it is possible that reindeer eyes are optimized to single out lichens during the times of year where it is most difficult to find since it is a food staple. 

The post Reindeer can see UV light—and we may know why appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Adjusting to life in cold air temperatures has been key to survival for the Arctic’s seals. Those adaptations go beyond thick layers of blubber for insulation and up into the pinniped’s nose. A study published December 14 in the Biophysical Journal found that Arctic seals have more convoluted nasal passages than seals that live in more mild places. 

[Related: Hungry seals may have begun following their whiskers 23 million years ago.]

Warming the air

In cold and dry places, animals lose moisture and heat when they breathe. Warmer and wet air is important for lung function, so breathing in cold air can put the lungs in danger and may make humans more susceptible to respiratory viruses. To help minimize the risk, most birds and mammal species have complex bones called maxilloturbinates inside their nasal cavities. These porous, bony shelves are covered with mucus and tissues that warm and humidify inhaled air. Maxilloturbinates also reduce the amount of heat and moisture that is lost when an organism breathes out.

Researchers believe that the nose structure helps Arctic seals efficiently retain moisture and heat as they inhale and exhale. 

“Thanks to this elaborate structure in their nasal cavities, Arctic seals lose less heat through nasal heat exchange than subtropical seals when both are exposed to the same conditions,” Signe Kjelstrup, a study co-author and physical chemist at the Norwegian University of Science and Technology, said in a statement. “This provides an evolutionary advantage, especially in the Arctic where heat loss is energy dissipation, which must be replenished by food.”

According to Kjelstrup, Arctic seals retain 94 percent of the moisture in the air when they breathe in and out. Most of the water added to the air when they inhale is then recovered when they exhale.  

‘You can’t find reindeer in the middle of the Mediterranean’

The structure of maxilloturbinates varies between species. Reindeer noses also enable efficient heat exchange, but since they are only found in colder climates, Kjelstrup’s team turned to seals.

“You can’t find reindeer in the middle of the Mediterranean, but seals live in many different environments, so they allowed us to test this question,” said Kjelstrup. “And we knew from a previous study that Arctic seal noses are sponge-like and very dense, whereas the Mediterranean seal nose has a more open structure.”

In the study, the team used computer tomography to create 3D models of the nasal cavities of two seal species–the Arctic bearded seal (Erignathus barbatus) and the Mediterranean monk seal (Monachus monachus). Next, they used energy dissipation models to compare how well each species warmed and moistened air when they inhaled and reduced the amount of heat and moisture lost when they exhaled.

[Related: Baby seals sing bass notes when they want attention.]

They tested the models of both species’ noses under Arctic conditions of -22°F and at about 50°F, or a cold day for a Mediterranean monk seal. They also adjusted different parameters within the model to highlight the crucial geometrical features of the nasal cavity.

According to the model, Arctic bearded seals are more efficient at retaining heat and water exchange in both Arctic and subtropical temperatures. At -22°F, the Mediterranean monk seals lost 1.45 times as much heat and 3.5 times as much water per breath cycle than the bearded seals lost. At 50°F, the Mediterranean monk seals lost 1.5 times as much heat and 1.7 times as much water.

It appears that the Arctic seal’s more complex and dense nasal cavity provided this advantage. Specifically, the team found that the increased perimeter of the Arctic seal’s maxilloturbinates is the key to limiting energy dissipation at lower ambient temperatures. 

While the study looked at the amount of heat loss for one inhalation and exhalation, the role breathing rate plays remains unclear. These breathing cycles are particularly complicated for seals, who will pause their breathing for several minutes at a time when they dive under water and ice.

Energy efficient pinnipeds

The team hopes to look deeper into the nasal structures of other species to see if different parts provide evolutionary advantages in other climates. 

“The camel, for instance, doesn’t need to save much on heat, but it does need to save on water, so one may speculate that it could tell us something about relative importance of the two,” said Kjelstrup.

They also plan to look to animals for cues on how to build more efficient heat exchange and ventilation systems. 

“If nature manages to create such great heat exchangers, I think we should copy that in engineering to create more efficient processes, for instance, in air conditioners,” said Kjelstrup.  

The post Arctic seals have special noses appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

If you naturally wake up earlier in the morning, some very old genetic variants may be behind your sleep patterns. Humans’ internal circadian clocks might be partially influenced by genetic material left behind by extinct Neanderthals. The findings are described in a study published December 14 in Genome Biology and Evolution and provides a window into how the sleep cycles of Neanderthals differed from our earliest ancestors. Studies like this one could be a step towards a better understanding of how genetic material from extinct hominins affects modern humans.   

Our bodies respond to the environment

Modern Homo sapiens trace their origins back 300,000 years. Biological features in these early humans were shaped by environmental factors like sunlight or altitude. Roughly 70,000 years ago, the ancestors of modern Eurasian humans began to migrate out of Africa north towards Europe and Asia. Here, they experienced new environments and more seasonal variation in both temperatures and daylight. 

[Related: Night owls can become early birds. Here’s how.]

“We also know from other species that live across broad ranges of latitude that their circadian clocks often adapt to the differences in light/dark cycles,” study co-author and University of California, San Francisco computational biologist Tony (John) Capra tells PopSci. “In particular, in higher latitudes there is more seasonal variation in light/dark cycles over the course of the year than in more equatorial latitudes.”

They also encountered different types of early hominins as they left Africa, including Denisovans and Neanderthals. The different environmental conditions on these northern continents meant that Neanderthals and Denisovans had different genetic variations from those coming out of Africa. When they began to interbreed with Neanderthals about 50,000 years ago, it created the potential for humans to get some of the genetic variants that were already adapted to this environment.

Which genes stay and which genes go

Roughly two percent of the present-day Eurasian genome is derived from Neanderthal genetic variants, but which two percent varies. Neanderthal genes have been shown to influence nose shape and even pain sensitivity. Natural selection can remove this older genetic ancestry that is not deemed beneficial to humans as we evolve. However, some of the older hominin genetic variants that remain in today’s human genome have evidence of adaptation. For example, Tibetans living at higher altitudes have variants associated with immune resistance to new pathogens, levels of skin pigmentation, fat composition, and differences in hemoglobin levels.

In the new study, Capra and co-authors were curious if the Neanderthals who lived at higher latitudes may have genetic variants that adapted to changes in environment over hundreds of thousands of years. They also wondered if the interbreeding influenced variation in the circadian rhythm that can make someone an early riser. 

[Related: Sex, not violence, could’ve sealed the fate of the Neanderthals.]

The researchers identified about 200 genes that are related to how light and temperature affects our circadian clock and about 20 that are crucial to our internal clocks themselves. “It turns out that the genes themselves are very similar, but what really matters is how much and when they are made,” says Capra. 

After pinpointing these genes, the team explored if the variants that moved from Neanderthals into modern humans have any associations with the body’s preferences for wakefulness and sleep. They looked at genetic data from the UK Biobank and found that many of the Neanderthal variants in modern humans affect sleep preference. In particular, the tendency to wake up early–or morningness–stuck out. Increased morningness is associated with a shortened circadian clock that is likely beneficial for those living at higher latitudes. Morningness has been shown to enable a faster alignment of the external cues that it’s time to fall asleep or wake up, like changes in sunlight. 

“We used machine learning methods to predict from Neanderthal DNA sequences how the ways that they turned the circadian genes on and off differed from in modern humans,” says Capra. “In general, it seems that having a faster running clock leads people (and other organisms) to be earlier risers and have an easier time adapting to seasonal variation.”

This increased morningness may have been evolutionarily beneficial for our ancestors living in higher latitudes, so the genetic variants associated with it would have been worth keeping. 

Sentinel hypothesis

Exploring the genetics behind what makes some of us early birds and others night owls is part of an emerging–yet difficult to prove–evolutionary theory called sentinel hypothesis. There could be an evolutionary benefit to having a mixture of sleep and wake patterns and in a given human population. To increase chances of survival, animals living in groups should trade off keeping watch, with some sleeping while others are awake. Study co-author and Vanderbilt University computational biologist Keila S. Velazquez-Arcelay identified a few genetic variants that could provide evidence for this.

“Keila discovered a few genetic variants that are associated with chronotype that have evidence of long-term ‘balancing’ selection. In other words, evolution appears to have preferred to maintain variation at these sites,” says Capra. 

In future work, the team from this study is interested in testing the effects of these Neanderthal genetic variants on circadian clocks in cells. According to Capra, using cells allows them to quickly introduce the Neanderthal variants and evaluate their effects. They are also curious to find patterns across different populations and see if this analysis technique can be applied to genes involved in immune system function, thermoregulation, and metabolism.

The post Neanderthals may have been early risers appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

When bioluminescent ostracods or ‘sea fireflies’ mate, they perform a courtship dance complete with glowing blue mucus. The males sway together in sync while basking in the light of the shiny slime. This mating ritual is detailed for the first time in a study published November 29 in the journal Proceedings of the Royal Society B.

[Related: Surprise! These sea cucumbers glow.]

Ostracods are tiny crustaceans that are about the size of a sesame seed. They are found in a variety of fresh and saltwater environments, from deep ocean depths to shallow seas to rivers, lakes, and estuaries. The dancing, shrimplike species in the study is called the entraining grassbed downer and was observed in the Caribbean Sea near Panama. 

During this dance routine, male EGDs create their distinct patterns of bioluminescence to attract females. They secrete packets of protein from a specialized gland. The females respond by angling themselves to these bright blue luminous displays and swimming towards the males. According to study co-author Nicholai Hensley, a Cornell University evolutionary biologist who specializes in animal behavior, the other males will then join in a synchronous light display and repeat the same pattern in the water during each dance.

The study found that this very coordinated swim also doesn’t happen randomly. The mating dance sequence only occurs after sunset at nautical twilight, when the moon isn’t bright in the night sky. The team found their level of precision and coordination very surprising. 

“This precise timing leads to the unexpected phenomena of huge waves of light that cascade across the grass bed, with hundreds of males displaying at the same time,” Hensley tells PopSci. “Amazingly, this is very similar in appearance to the fireflies most people are familiar with, where some species are also synchronized. But ostracods and fireflies last shared a common ancestor 500 million years ago, when most animal life was evolving beyond looking slightly more than worm-like.”

Ostracods are special because they evolved their bioluminescence and bioluminescent behaviors completely independently from other animals that act like them. “They are also spectacular little animals, whose whole world escapes notice by 98 percent of people unless you know where to look,” says Hensley.

Luckily, some of Hensley’s collaborators knew where to look and had some luck on their side. In 2017, James Morin, a professor emeritus of ecology and evolutionary biology at Cornell and Todd Oakley, a professor at the University of California, Santa Barbara were diving near the Smithsonian Tropical Research Institute’s Bocas del Toro island research station in Panama. When Morin turned on his dive light to test it out, hundreds of ostracods responded with their own light. According to Morin, there are more than 100 species of signaling ostracods in the Caribbean alone.

[Related: These newly discovered bioluminescent sea worms are named after Japanese folklore.]

“What’s really remarkable about EGD is the duration, the brightness and the density,” Morin said in a statement. “It was a remarkable experience. They really jump out at you. I’ve worked with ostracods for years and this species is spectacular.”

With this discovery, Hensley and study-co-author Trevor Rivers from the University of Kansas set up some preliminary experiments to determine just what the animals were responding to when a light flashed on them. They found that the EDGs are very sensitive to both the time and intensity of a light. 

“It’s how they coordinate their own signals with one another,” says Hensley.

The courtship ritual with snotty light likely evolved about 20 million years ago. However, why the males perform these gyrations is still a mystery. The team only knows that these displays are for attraction purposes, and are still figuring out the other functions. It’s possible that the males are competing with one another for attention, which leads to what Hensley calls a “giant free-for-all.” They also may be cooperating to make a brighter display that could attract more females. The team plans on testing how these displays look to females and measuring their behaviors to better understand this mating dance.

“There’s a whole world filled with new questions and unexplored ideas out there if you pay attention to the little details around you,” says Hensley. “Get out there, pay attention, and take chances, make sure to seize the moments of the rare opportunities that come your way. You can’t predict where it will lead, but you can be sure you learn something along the way.”

The post Watch the mucus-filled, synchronized mating dance of bioluminescent ‘sea fireflies’ appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Crocodiles are some of the most fierce ambush-predators in the world. There are only 24 crocodilian species around the world and seven are considered Critically Endangered by the international Union for Conservation of Nature and Natural Resources. Now, a team of scientists have mapped the crocodile family tree, including their extinct relatives called Pseudosuchia. The family tree is detailed in a study published December 4 in the journal Nature Ecology & Evolution and offers insight into the role that the environment has historically played on crocodile evolution. 

[Related: Why scientists gave vaccines to farmed crocodiles.]

Ruling reptiles

Crocodiles and birds share an evolutionary heritage with dinosaurs and pterosaurs, despite there being 11,000 living bird species compared to only 24 crocodile species. Crocodiles are the only living members of a mostly extinct clade called archosaurs or “ruling reptiles.” Archosaurs date back to the Early Triassic, about 251 million to 200 million years ago. 

Archosaurs belong to a group called Pseudosuchia, which includes multiple species that are more closely related to crocodiles than they are to birds. Pseudosuchias went extinct at or before the Triassic–Jurassic extinction event about 201.4 million years ago. However, one group called the crocodylomorphs, survived the major extinction and gave rise to the crocodiles. 

“The fossil record is a rich source of valuable information allowing us to look back through time at how and why species originate, and crucially, what drives their extinction,” study co-author and University of York biologist Katie Davis said in a statement. 

In the study, a team of researchers used the fossil record to build a large phylogeny, or evolutionary family tree of a species or group. The phylogeny included crocodiles and their extinct relatives, so the team could map out how many new species were being formed and how many species were going extinct over time. They then combined this family tree with data on past changes in climate. They were particularly interested in changes to temperature and sea levels to see if the emergence and extinction of species could be linked to climate change. 

Climate change and competition

They found that climate change and competition with other species have shaped the diversity of modern-day crocodiles and their extinct relatives. Surprisingly, the phylogeny also revealed that whether species lives in freshwater, in the sea, or on land plays a key role in its survival. 

When global temperatures increased, the number of species of the modern crocodile’s sea-dwelling and land-based relatives also went up. 

[Related: Crocodiles’ ancient ancestors may have walked on two legs.]

The crocodile’s freshwater relatives were not affected by changes in temperatures. Rising sea levels proved to be their greatest risk for extinction. According to the team, these results provide important insights for conservation efforts of crocodiles and other species in the face of human-made climate change. 

“With a million plant and animal species perilously close to extinction, understanding the key factors behind why species disappear has never been more important,” said Davis. “In the case of crocodiles, many species reside in low-lying areas, meaning that rising sea levels associated with global warming may irreversibly alter the habitats on which they depend.”

To look at how competition might have played a role, the team used the Information Theory. They calculated estimates of numbers of species present at any point in time and compared that number against new species and extinctions. These calculations allowed the team to estimate where climate change or species interactions like competition had a direct impact on whether new species were emerging or going extinct. Unsurprisingly, an increase in competition for resources, possibly from sharks, marine reptiles, or dinosaurs, likely caused the extinction of some species. 

“Crocodiles and their extinct relatives offer unique insights into climate change and its impact on biodiversity in the past, present and future,” said Davis. “Our findings advance our understanding of what factors have shaped, and continue to shape, life on Earth.”

The post Tracing the crocodiles’ curious evolutionary family tree appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

If you’ve ever been bitten by a mosquito, it was a female insect that chomped on your skin. Female mosquitoes are hematophagous, which means that they feast on animal blood. They then use the blood to produce their eggs. Male mosquitoes living today are not hematophagous. Instead, they survive on plant nectar because their piercing mouthparts–the proboscis–aren’t strong enough to pierce skin.

[Related: When insects got wings, evolution really took off.]

However, male mosquitoes may have been blood suckers hundreds of millions of years ago. A team of paleontologists found two male mosquito fossils from the Lower Cretaceous period with intact piercing proboscis and sharp mandibles needed to suck blood. The specimens are described in a study published December 4 in the journal Current Biology and help to narrow a “ghost-lineage gap” for mosquitoes.

Hematophagy is the ability for insects to suck on the blood of other animals. It’s believed to have evolved from a shift to using piercing-sucking mouthparts to extract fluids from plants instead of animals. Fleas that currently suck animal blood possibly arose from earlier species of the insects that primarily fed on plant nectar. The evolution of hematophagy has been more difficult to trace, partially due to gaps in the insect fossil record.

The fossils examined for this study were found preserved in amber in Lebanon and date back about 130 to 125 million years. Amber is a fossilized tree resin and deposits in Lebanon are some of the oldest known amber samples that contain traces of living things including insects. Studying this material can close “ghost-lineage gaps,” or a chain of ancestors that does not usually appear in the fossil record. Coelacanths are a famous example of a ghost-lineage gap. These lobe-finned have a long fossil record from the Devonian to the Cretaceous–or a period of about 300 million years. However, they were not found in sediments younger than the Cretaceous, so scientists assumed that they had been extinct 80 million years. A living coelacanth was caught off the coast of South Africa in 1938 and another population lives in Indonesia. Coelacanths have just not left any fossils over the past 80 million years. 

Amber deposits can also offer scientists clues into how pollinating bugs and flowering plants co-evolved over time. The pollinators include some members of the Culicidae family of arthropods which has over 3,000 species of mosquitoes. 

“Molecular dating suggested that the family Culicidae arose during the Jurassic, but previously the oldest record was mid-Cretaceous,” study co-author and entomologist at the National Museum of Natural History of Paris André Nel said in a statement. “Here we have one from the early Cretaceous, about 30 million years before.”

[Related: How can we control mosquitos? Deactivate their sperm.]

In the new study, the team describes the fossils of two male mosquitoes from the Cretaceous period that have piercing mouthparts. The parts include a very sharp triangular mandible and elongated structure with small, tooth-like denticles. The presence of these parts suggest that male mosquitoes living during the Late Cretaceous could have been strong enough to pierce the skin and feed on animal blood like their modern female descendents. 

The team also reports that the mosquitoes’ preservation in amber stretches the family tree of insects further back into the Cretaceous period. The fossils also suggest that the evolution of blood-sucking behavior was more complicated than they had previously suspected. According to Nel, the team hopes to investigate why being hematophagous was advantageous to Cretaceous male mosquitoes and why it no longer exists in future studies. 

The post Millions of years ago, male mosquitoes may have been blood suckers too appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Cooperation between different groups of humans lies at the root of our social norms, traditions, and culture. Groups of a great ape species called bonobos may also work collaboratively with other cliques, according to a study published November 16 in the journal Science.

[Related: Bonobo ladies get to choose their mates and boy oh boy are they picky.]

Along with chimpanzees, bonobos are some of our closest living relatives. Studying their relationships can help scientists reconstruct what human traits appear to be more innate and how they evolve. However, both species of primate exhibit different levels of cooperation despite living in similar social groups that have multiple adult members of both sexes. 

Chimpanzees appear to have more hostile relationships between different groups. Even lethal aggression is not uncommon. This hostility has led researchers to assume that group conflict is an innate part of human nature. 

Bonobos might be telling a different story about how social structures and communities have evolved over time. 

“The ability to study how cooperation emerges in a species so closely related to humans challenges existing theory, or at least provides insights into the conditions that promote between-group cooperation over conflict,’ study co-author and German Primate Center evolutionary biologist Liran Samuni said in a statement.

The study looked at two groups of 31 wild adult bonobos in the Kokolopori Bonobo Reserve in the Democratic Republic of Congo over a period of two years. When the different groups of bonobos met up, they often fed, rested, and traveled together. 

“Tracking and observing multiple groups of bonobos in Kokolopori, we’re struck by the remarkable levels of tolerance between members of different groups,” Samuni said. “This tolerance paves the way for pro-social cooperative behaviors such as forming alliances and sharing food across groups, a stark contrast to what we see in chimpanzees.” 

The authors also did not observe disputes that led to the lethal aggression that has been observed in chimpanzees. The bonobos did not not interact randomly between groups. Cooperation only happened among a select few group members. 

“They preferentially interact with specific members of other groups who are more likely to return the favor, resulting in strong ties between pro-social individuals,” study co-author and Harvard University evolutionary biologist Martin Surbeck said in a statement. “Such connections are also key aspects of the cooperation seen in human societies. Bonobos show us that the ability to maintain peaceful between-group relationships while extending acts of pro-sociality and cooperation to out-group members is not uniquely human.”

[Related: Humans owe our evolutionary success to friendship.]

Cooperation between human groups leads to exchanges of ideas, knowledge, innovation, and resources. The Bonobos in the study also shared food resources across groups without any strong cultural influence. The authors believe that this challenges another existing idea that a shared culture and traits are necessary components for groups to cooperate with one another. 

The study also highlights the importance of collaboration when studying bonobos that live in remote and largely inaccessible parts of the preserve. 

“It is through strong collaborations with and the support of the local Mongandu population in Kokolopori, in whose ancestral forest the bonobos roam, that studies of this fascinating species become possible,” said Subeck, who directs research in the Kokolopori Bonobo Reserve. “Research sites like Kokolopori substantially contribute not only to our understanding of the species’ biology and our evolutionary history, but also play a vital role in the conservation of this endangered species.”

The post Wild bonobos show surprising signs of cooperation between groups appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Dinosaur Mysteries digs into the secretive side of the “terrible lizards” and all the questions that keep paleontologists up at night.

YOU NEVER KNOW how small you are until you’re next to a big ol’ dinosaur. Find the right lighting in the museum hall and you can literally stand in the shadow of the skeletons of Apatosaurus, Patagotitan, Brachiosaurus, and other reptiles that grew far larger than any other terrestrial creature in the past 66 million years. But even after nearly two centuries of research, we have only the haziest notions of why some dinosaurs were larger than any terrestrial mammal to date.

While a number of dinosaurs fell in the supersized category—Tyrannosaurus rex weighed more than a mature male African elephant—the sauropods were the all-time titleholders. They had small heads with simple teeth, impressively long necks, hefty bodies, and tapering tails. So many sauropod species reached more than 100 feet in length, paleontologists still aren’t sure which one stretched the farthest. While the largest land mammals, like the hornless rhino Paraceratherium and the biggest fossil elephants, got to be about 18 tons, sauropods evolved to have more mass at least 36 times during their evolutionary history—an ongoing reprisal of gargantuan herbivores through the Jurassic and Cretaceous.

The stunning heft of these creatures has often led us to wonder why they got to be so much bigger than any terrestrial creature before or since. But in the realm of paleontology, “why” questions are extremely difficult to answer. Queries starting with “why” are matters of history, and in this case, the history plays out dozens of times on multiple continents over the course of more than 130 million years. Though we see the end effect, we can’t quite make out the causes.

Dinosaurs have a habit of digging their claws into our imaginations, however, so researchers have kept on, turning up a few clues in the past two decades about the surfeit of superlative sauropods. While higher oxygen levels have been linked to bigger body sizes in a few ancient insects, the atmosphere in the heyday of the dinosaurs was about the same as today’s. What’s more, the Earth’s gravitational force was just as strong in the Mesozoic era as in the modern era. So we know that the impressive size of Argentinosaurus and other top sauropods was not a matter of an abiotic factor like increased oxygen in the atmosphere or lower gravity. Our explanation lies elsewhere.

Paleontologists are getting closer to the truth by looking at the dinosaurs themselves. For example, experts have identified a suite of characteristics that set sauropods apart from the mastodons and giant rhinos of the Cenozoic. Eggs have a great deal to do with it.

The largest mammals of all time were placentals, gestating their offspring on the inside so they could come out more developed. This reproductive strategy comes with some constraints. To reach even larger adult sizes, females of each species would need to carry their babies in the womb for longer. African elephants, for example, already gestate for about two years—during which much can go wrong. But sauropods, like all nonavian dinosaurs, laid multiple eggs at a time, bypassing the reproductive constraints of live birth and flooding their ecosystems with tons of babies that had the potential to grow huge (even if most ended up as snacks for the carnivores of the time). The different reproductive strategies gave dinosaurs some advantages over mammals.

Camarasaurus and other sauropods also got some assistance from their anatomical peculiarities. Sauropods had complex air-sac systems in their respiratory tracts that created air pockets within and around their bones. These nifty features kept their skeletons light without sacrificing strength, and also made extracting oxygen from the air and shedding excess body heat more efficient. The distinctive dinosaurs could grow long necks too, because they didn’t have heavy heads full of massive, grinding teeth like large herbivorous mammals over the past 66 million years. Instead, sauropods had small, light noggins full of spoon- or pencil-shaped teeth that were mostly just capable of cropping vegetation to be broken down and fermented through their gastrointestinal tracts. In other words, their guts did the work, not their teeth. Studies of ginkgoes, horsetails, and other common Mesozoic plants indicate that the ancient vegetation was more calorie-rich than previously supposed, so the abundance of green food likely fueled the reptilian giants’ unprecedented growth.

But these facts only show us what allowed sauropods to become big. The dinosaurs didn’t have to drift in that direction. In fact, some were relatively small: The island-dwelling species Magyarosaurus was about the size of a large cow. Sauropods could have thrived at smaller sizes, but they instead kept spinning off lineages of giants. We know something about what made living large possible, but what we still don’t know is what evolutionary pressures drove sauropods to evolve enormous bodies.

Predators certainly played their part. All sauropods were born small—even the largest species hatched from eggs about the size of a soccer ball. They were vulnerable to various Jurassic and Cretaceous carnivores, but growing up quickly was one way to stave off those hungry jaws. Hunting megafauna can be dangerous and even deadly, as we see with lions, wolves, and even humans today, and so sauropods may have plumped up to be less appealing to the likes of Allosaurus and T. rex.

But if carnivorous appetites were the main driver of sauropod size, we’d see a more uniform and extended “arms race” between the dinosaurs over time, resulting in gradually larger predators and prey. The fossil record instead shows that sauropods scaled up in different times and places, likely for an array of reasons ranging from local grub to what mating sauropods found sexy in each other. The repeated evolution of gigantic dinosaurs hints that there were many pathways to the sauropods’ impressive stature, not just one. Biology was as complicated back then as it is now, and we’ll never get the full story without experiencing 100-foot-long reptiles ourselves.

Read more PopSci+ stories.

The post The mystery of why some dinosaurs got so enormous appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

While the majority of fish are cold-blooded and rely on the temperature outside of their bodies to regulate their internal temperatures, less than one percent of sharks are actually warm-blooded. The extinct but mighty megalodon and the living great white shark generate heat with their muscles the way many mammals do. However, they are not the only sharks with this warm quirk. A study published November 7 in the journal Biology Letters found that there are more warm blooded sharks than scientists initially believed. 

[Related: Megalodons were likely warm-blooded, despite being stone-cold killers.]

Warmer muscles might help these giant carnivores be more powerful and athletic, by using that heat to generate more energy. Regional endothermy in fish has been seen in apex predators like the great white or giant tuna, but there has been debate on when this warm bloodedness evolved in sharks and if the megalodon was warm blooded. A previous study from June 2023 found that the megalodon was warm blooded and that the amount of energy it used to stay warm may have contributed to its extinction about 3.6 million years ago.

The new study looked at the results of autopsies from some unexpected shark strandings in Ireland and southern England earlier in 2023. The sharks belonged to a rarely seen species called the smalltooth sand tiger shark. These sharks are found around the world in temperate and tropical seas and in deep waters (32 to 1,700 feet deep). They have a short and pointed snout, small eyes, protruding teeth, and small dorsal and anal fins and can reach about 15 feet long. Smalltooth sand tiger sharks are considered a “vulnerable” species by the International Union for the Conservation of Nature. While they are not targeted by commercial fisheries, the sharks may be mistakenly caught in nets and may face threats from pollution. 

Smalltooth sand tiger sharks are believed to have diverged from the megalodon at least 20 million years ago. The autopsies from this year’s stranded sharks unexpectedly served as a timeline that took marine biologists from institutions in Ireland, South Africa, and the United States back millions of years. 

The team found that these rare sharks have physical features that suggest they also have regional endothermy like the megalodon, great white, and some filter-feeding basking sharks. This new addition means that there are likely more warm-blooded sharks than scientists thought and that warm bloodedness evolved quite a long time ago.

“We think this is an important finding, because if sand tiger sharks have regional endothermy then it’s likely there are several other sharks out there that are also warm-bodied,” study co-author and marine biologist Nicholas Payne said in a statement. “We used to think regional endothermy was confined to apex predators like the great white and extinct megalodon, but now we have evidence that deep water ‘bottom dwelling’ sand tigers, and plankton-eating basking sharks also are warm bodied. This raises plenty of new questions as to why regional endothermy evolved, but it might also have important conservation implications.” Payne is affiliated with Trinity College in Dublin, Ireland. 

[Related: Were dinosaurs warm-blooded or cold-blooded? Maybe both.]

Scientists believe that the megalodon’s warmer body allowed it to move faster, tolerate colder water, and spread all over the world’ oceans. However, this evolutionary advantage could have contributed to its downfall. The megalodon lived during the Pliocene Epoch (5.33 million years to 2.58 million years ago) when the world cooled and sea levels changed. These ecosystem changes and competition with newcomers in the marine environment like great whites may have led to its extinction. 

Understanding how extinct sharks met their end could help scientists gauge how today’s warm-blooded sharks could fare due to warmer ocean temperatures from human-caused climate change. It has potential conservation implications and could explain some shifting patterns of where sharks are foraging. 

“We believe changing environments in the deep past was a major contributor to the megalodon’s extinction, as we think it could no longer meet the energetic demands of being a large regional endotherm,” study co-author and Trinity College marine biologist Haley Dolton said in a statement. “We know the seas are warming at alarming rates again now and the smalltooth tiger that washed up in Ireland was the first one seen in these waters. That implies its range has shifted, potentially due to warming waters, so a few alarm bells are ringing.”   

The post Megalodon’s warm-blooded relatives are still circling the oceans today appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Humans are the only primates currently living in the wild in North America, but that was not always the case. The continent was once home to non-human primates, including big-eyed tarsier-like animals called omomyiforms and long-tailed critters called adapiforms. About 30 million years ago, a lemur-like creature named Ekgmowechashala was the last primate to inhabit the continent before Homo sapiens arrived. In a study published November 6 in the Journal of Human Evolution, fossil teeth and jaws shed some new light on this mysterious creature. 

[Related: 12-million-year-old ape skull bares its fangs in virtual reconstruction.]

From China to Nebraska

Understanding the origins of North America’s primates has been a paleontological puzzle. It’s been unclear whether they evolved on the continent or arrived from somewhere else via land bridges. The first first primates in North America date back about 56 million years at the beginning of the Eocene Epoch. Scientists believe that the primates like Ekgmowechashala generally flourished on the continent for over 20 million years. 

Ekgmowechashala was about five pounds and only one foot tall. They lived in what is now the American Plains just after the Eocene-Oligocene transition. At this time, a huge cooling and dying event made the continent much less hospitable for primates. Ekgmowechashala went extinct about 34 million years ago. 

For the study, paleontologists first had to reconstruct Ekgmowechashala’s family tree with the help of  an older “sister taxon,” or a closely related group of animals. Both groups generally share a branch on their family trees, but diverged at some point and have different lineages. This sister animal originates in and the team named it Palaeohodites, which means “ancient wanderer.” The fossils were collected by paleontologists from the United States in the 1990s from the Nadu Formation in Guangxi, an autonomous region in China. The fossils closely resembled the Ekgmowechashala material that had been found in North America in the 1960s, when the primate was still quite mysterious to North American paleontologists.

The Palaeohodites fossil potentially helps resolve the mystery of Ekgmowechashala’s strange presence in North America. It was likely a migrant to the continent instead of being the product of local evolution.

“Due to its unique morphology and its representation only by dental remains, its place on the mammalian evolutionary tree has been a subject of contention and debate. There’s been a prevailing consensus leaning towards its classification as a primate,” study co-author and University of Kansas PhD candidate Kathleen Rust said in a statement. “But the timing and appearance of this primate in the North American fossil record are quite unusual. It appears suddenly in the fossil record of the Great Plains more than 4 million years after the extinction of all other North American primates, which occurred around 34 million years ago.”

[Related: These primate ancestors were totally chill with a colder climate.]

The Ekgmowechashala fossils found in the US during the 1960s include an upper molar that looks very similar to the Palaeohodites molars found in China, according to study co-author and University of Kansas paleontologist Chris Beard. The team from Kansas closely analyzed the fossils to establish evolutionary relationships between the American Ekgmowechashala and its cousin Palaeohodites. 

The paleontologists believe that Ekgmowechashala did not descend from an older North American primate that survived the climate shift roughly 33 million years ago that caused other North American primates to go extinct. Instead, Ekgmowechashala’s ancestors likely crossed over the icy Beringian region that once connected Asia and North America millions of years later.

Rising from the dead

Ekgmowechashala is an example of the “Lazarus effect” in paleontology. This is where a species suddenly appears in the fossil record long after their relatives have died off. It is a reference to Lazarus who, according to New Testament mythology, was raised from the dead. It is also a pattern of evolution seen in the fossil record of North American primates, who went extinct about 34 million years ago. 

“Several million years later Ekgmowechashala shows up like a drifting gunslinger in a Western movie, only to be a flash in the pan as far as the long trajectory of evolution is concerned,” Beard said in a statement. “After Ekgmowechashala is gone for more than 25 million years, Clovis people come to North America, marking the third chapter of primates on this continent. Like Ekgmowechashala, humans in North America are a prime example of the Lazarus effect.”

The past is prologue?

Studying the way primates were affected by previous changes in climate can provide important insight to today’s human-driven climate change. Organisms generally retreat to more hospitable regions with the available resources or end up going extinct. 

“Around 34 million years ago, all of the primates in North America couldn’t adapt and survive. North America lacked the necessary conditions for survival,” said Rust. “This underscores the significance of accessible resources for our non-human primate relatives during times of drastic climatic change.

The post North America was once home to some unusual wild monkeys appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Scavenging has been maligned as a food gathering strategy and is generally associated with animals like vultures and hyenas. Millions of years ago, carnivorous dinosaurs may have evolved this technique of taking meat from dead carcasses too. The findings are described in a study published November 1 in the open-access journal PLOS ONE.

[Related: Dinosaur cannibalism was real, and Colorado paleontologists have the bones to prove it.]

Carnivorous dinosaurs like the cannibalistic Allosaurus were surrounded by both living and dead prey. The bodies of large sauropod dinosaurs, some of whom could weigh more than 500,000 pounds, could have provided an important food source for carnivores.

In this study, a team of researchers from Portland State University created a simplified computer simulation of a dinosaur ecosystem from the Jurassic age. They used the animals that have been found in the 163.5 to 145 million year-old Morrison Formation in the western United States as the basis. This enormous fossil formation was once home to a wide variety of plants and dinosaurs.

The model included large carnivores common to the area like Allosaurus, large sauropods and their carcasses, and a large group of living and huntable Stegosaurus’. The carnivores were assigned traits that would improve their hunting abilities with the energy from living meat sources or their scavenging abilities with the sustenance from the carcasses. The model then measured the evolutionary fitness of the simulated predators. 

The model found that when there were a large amount of sauropod carcasses around, scavenging was more profitable than hunting for the Allosaurus. Meat eaters in these kinds of ecosystems may have evolved specialized traits to help them detect and exploit these large carcasses.

“Our evolutionary model demonstrates that large theropods such as Allosaurus could have evolved to subsist on sauropod carrion as their primary resource,” the authors wrote in a statement. “Even when huntable prey was available to them, selection pressure favored the scavengers, while the predators suffered from lower fitness.”

[Related: This 30-pound eagle would take down 400-pound prey and dig through their organs.]

This model represents only a simplified depiction of a complex ecosystem, so more variables like additional dinosaur species may alter the results. While theoretical, using models like this one can help scientists better understand how the availability of meat from carcasses can influence how predators evolve. A September 2023 modeling study found that even early humans living in southern Europe roughly 1.2 to 0.8 million years ago were scavengers. They may have competed in groups of five or more to fight off extinct giant hyenas for the carcasses of animals that had been abandoned by larger predators like saber-toothed cats.

“We think allosaurs probably waited until a bunch of sauropods died in the dry season, feasted on their carcasses, stored the fat in their tails, then waited until the next season to repeat the process,” the authors wrote. “This makes sense logically too, because a single sauropod carcass had enough calories to sustain 25 or so allosaurs for weeks or even months, and sauropods were often the most abundant dinosaurs in the environment.”

The post When a Jurassic giant died, predatory dinos probably feasted on the carcass appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

When looking at a sea star–or starfish–it’s not really clear which part of its identical five pointed body is considered its head. This question has puzzled biologists for decades, but some new research says that a starfish’s whole body could function like a head. The findings are described in a study published November 1 in the journal Nature and might have solved the mystery of how sea stars and other echinoderms evolved their distinctively shaped bodies.

[Related: This strange 500-million-year-old sea urchin relative lost its skeleton.]

Searching for heads and trunks 

Sea stars are invertebrates that belong to a group of animals called echinoderms.This group also includes sea urchins and sand dollars and they all have bodies that are arranged in five equal and symmetric sections. Early in their evolution, echinoderms had a bilaterally designed ancestor with two mirrored sides more like a human’s. 

“How the different body parts of the echinoderms relate to those we see in other animal groups has been a mystery to scientists for as long as we’ve been studying them,” Jeff Thompson, a co-author of the study and evolutionary biologist at the University of Southampton in the United Kingdom, said in a statement. “In their bilateral relatives, the body is divided into a head, trunk, and tail. But just looking at a starfish, it’s impossible to see how these sections relate to the bodies of bilateral animals.”

In the new study, an international team of scientists compared the molecular markers in sea stars with a wider group of animals called deuterostomes. This group includes echinoderms like sea star and bilateral animals including vertebrates. Deuterostomes all share a common ancestor, so comparing their development can offer clues into how echinoderms evolved their more unique five-pointed body plan.

They used multiple high-tech molecular and genomic techniques to see where different genes were expressed during a sea star’s development and growth. Micro-CT scanning also allowed the team to understand the shape and structure of the animals in closer detail.

Sea star mapping

Team members from Stanford University, the University of California, Berkeley, and Pacific BioSciences, used techniques called RNA tomography and in situ hybridization to build a three-dimensional map of a sea star’s gene expression to see where specific genes are being expressed during development. They specifically mapped the expression of the genes that control the growth of a sea star’s ectoderm, which includes its nervous system and skin. 

They found gene signatures associated with head development almost everywhere in juvenile sea stars. The expression of genes that code for an animal’s torso and tail sections were also largely missing.

[Related: What’s killing sea stars?]

“When we compared the expression of genes in a starfish to other groups of animals, like vertebrates, it appeared that a crucial part of the body plan was missing,” said Thompson. “The genes that are typically involved in the patterning of the trunk of the animal weren’t expressed in the ectoderm. It seems the whole echinoderm body plan is roughly equivalent to the head in other groups of animals.”

The molecular signatures that are typically associated with the front-most portion of an animal’s head were also localized towards the middle of each of the sea star’s five arms. 

“It’s as if the sea star is completely missing a trunk, and is best described as just a head crawling along the seafloor,” study co-author and Stanford University evolutionary biologist Laurent Formery said in a statement. “It’s not at all what scientists have assumed about these animals.” 

Sea stars and other echinoderms may have evolved their five-section body plan by losing the trunk region that their bilateral ancestors once had. This chance would have allowed them to move around and feed differently than animals with two symmetrical arms.

“Our research tells us the echinoderm body plan evolved in a more complex way than previously thought and there is still much to learn about these intriguing creatures,” said Thompson. “As someone who has studied them for the last ten years, these findings have radically changed how I think about this group of animals.”

This research was supported by the Leverhulme Trust, NASA, the NSF, and the Chan Zuckerberg BioHub.

The post The sea star’s whole body is a head appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Lampreys are the vampires of the ocean and the lakes they can invade. While these eel-like parasitic vertebrates don’t use two sharp fangs to suck blood, lampreys have a toothed oral sucker that latches onto their prey and feasts on their host’s blood. Modern day lampreys are found in temperate zones of most of the world’s oceans except in Africa. However, specimens of their extinct ancient ancestors are fairly rare in the fossil record, despite dating back roughly 360 million years. Now, paleontologists in northern China have found two unusually large fossilized lamprey species that fill a large evolutionary gap. The specimens are described in a study published October 31 in the journal Nature Communications.

[Related: Why sea lampreys are going to be a bigger problem for the Great Lakes.]

“We found the largest fossil lampreys ever found in the world,” study co-author and Chinese Academy of Sciences paleontologist Feixiang Wu tells PopSci. “Based on these fossils, our study assumed that the most recent common ancestor of modern lampreys was likely eating flesh rather than sucking blood as conventionally believed.”

The earliest known lampreys date back about 360 million years ago during the Paleozoic Era. These early species are believed to have been only a few inches long and had weak feeding structures. The 160 million-year-old fossils in this new study were discovered in the Lagerstätte Yanliao Biota in northeastern China and date back to the Jurassic. The longer of the two specimens is named Yanliaomyzon occisor. It is more than 23 inches long and is estimated to have had 16 teeth. The shorter 11 inch-long species is named Yanliaomyzon ingensdentes and had about 23 teeth. By comparison, modern lampreys range from six to 40 inches long.

Their well-preserved oral discs and “biting” structures indicate that these lamprey species had already evolved enhanced feeding structures, bigger body size, and were predators by the Jurassic period. It also appears that they had already evolved a three-phased life cycle by this point

Lampreys begin their lives as burrowing freshwater larvae called ammocetes. During this stage, they have rudimentary eyes and feed on microorganisms with their toothless mouths. They spend several years in this stage, before transforming into adults. Some move into saltwater, while others will remain in freshwater. As adults, they become parasites that attach to a fish with their mouths and feed on their blood and tissue. Lampreys eventually return to freshwater to reproduce, where they build a nest, then spawn, and then die.

It is still unclear when lampreys evolved this lifecycle and their more complex teeth for feeding. These new well-preserved fossils fill an important gap in the fossil record and give some insights into how its lifecycle and feeding originated. 

[Related: Evolution made mosquitos into stealthy, sensitive vampires.]

The study also pinpoints where and when today’s lamprey’s first appeared. “We put modern lampreys’ origin in the Southern Hemisphere of the Late Cretaceous,” says Wu. 

The Late Cretacous lasted from 100.5 million years ago to 66 million years ago and ended with the mass extinction event that wiped out the dinosaurs. In future research, the team would like to search for specimens from the Cretaceous. According to Wu, this time period could be very important to their evolutionary history.

More fossilized specimens could also provide more accurate ideas of what kinds of flesh ancient lampreys feasted on with all those teeth and how that has evolved over time. 

“Living lampreys are always hailed as ‘water vampires,’ but their ancestor might be a flesh eater, their teeth tell,” says Wu. 

The post Giant prehistoric lamprey likely sucked blood—and ate flesh appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Paleontologists in North Dakota have discovered new species of mosasaur. These giant meat-eating aquatic lizards swam the Earth’s seas about 80 million years ago during the late Cretaceous period. This new species is named Jormungandr walhallaensis after a sea serpent in Norse mythology named Jörmungandr and Walhalla, North Dakota where its fossils were found. The findings are described in a study published October 30 in the Bulletin of the American Museum of Natural History.  

[Related: Dinosaurs who stuck together, survived together.]

“If you put flippers on a Komodo dragon and made it really big, that’s what it would have looked like,” study co-author and Richard Gilder Graduate School PhD student Amelia Zietlow, said in a statement.

The first mosasaur specimens were discovered over 200 years ago and the word “mosasaur” even predates the word “dinosaur” by roughly 20 years. There are still several unanswered questions about these ancient sea lizards, including how many times they evolved to have flippers and when they became fully aquatic. Scientists believe that they evolved to have their signature flippers at least three times and possibly four or more. It is also still a mystery if mosasaurs are more closely related to present day monitor lizards or snakes or another living creature entirely. This new specimen fills in some knowledge gaps of how the different groups of mosasaurs are related to each other.

“As these animals evolved into these giant sea monsters, they were constantly making changes,” Zietlow said. “This work gets us one step closer to understanding how all these different forms are related to one another.”

Researchers in northeastern North Dakota first discovered the Jormungandr fossil in 2015. It included a nearly complete skull, jaws, and cervical spine, and a number of vertebrae. An extensive analysis revealed that the fossil is of a new species that has multiple features that are also seen in two other mosasaurs: Clidastes and Mosasaurus. Clidastes is a smaller animal of about six to 13 feet long that lived roughly 145 million years ago. Mosasaurus was much larger at almost 50 feet long and lived about 99.6 to 66 million years ago alongside the Tyrannosaurus rex. 

[Related: This four-legged snake fossil was probably a skinny lizard.]

The new specimen is about 24 feet long and has flippers. It also has a shark-like tail similar to other early mosasaur species. It also likely would have had “angry eyebrows,” caused by a bony ridge on its skull. Its slightly stumpy tail would have also been shorter than the rest of its body.

Jormungandr was likely a precursor to the bigger Mosasaurus. 

“This fossil is coming from a geologic time in the United States that we don’t really understand,” study co-author and paleontologist from the North Dakota Geological Survey Clint Boyd said in a statement. “The more we can fill in the geographic and temporal timeline, the better we can understand these creatures.”

In Norse mythology, Jörmungandr is an enormous sea serpent or worm who encircles the Earth. Jörmungandr is believed to be the middle child of the trickster god Loki and the giantess Angrboða. Thor the god of thunder also has an ongoing battle with Jörmungandr and it is believed that the two will fight to the death during Ragnarok, or the end of the world. 

The post Newfound mosasaur was like a giant Komodo dragon with flippers appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Living long lives past reproductive age is a real rarity for female members of the animal kingdom. Humans and some species of toothed whales are the only known animals to go through menopause and the reasons behind it are an evolutionary puzzle. A team of primatologists recently found that a group of wild chimpanzees in Uganda also show signs of menopause. The findings are described in a study published October 26 in the journal Science and could provide more insight into this rare biological phenomenon.

[Related: Adolescent chimpanzees might be less impulsive than human teens.]

In humans, menopause typically occurs between the ages of 45 and 55 and is characterized by a natural decline in reproductive hormones and the end of ovarian functions. Some symptoms in humans include chills, hot flashes, weight gain, and thinning hair. The evolutionary benefits of this process are still a mystery for biologists. It is also still unclear why menopause evolved in humans but not in other known long-lived primates. 

“During our ongoing twenty five year study of chimpanzees at Ngogo in Kibale National Park, Uganda, we noticed that many old females did not reproduce for decades,” study co-author and Arizona State University primatologist Kevin Langergraber tells PopSci. “It’s a surprising trait from the perspective of evolution: how and why can natural selection favor the extension of lifespan past the point at which individuals can no longer reproduce? We need to know in what species it occurs and which it doesn’t as a first step [to that question].”

To look closer, the authors calculated a metric called the post-reproductive representation (PrR). This measurement is the average proportion of adult lifespan that an animal spends in its post-reproductive state. Most mammals have a PrR close to zero, but the team found that Ngogo chimpanzees have a PrR of 0.2. This means that the female chimpanzees in this group live 20 percent of their adult years in a post-reproductive state. 

Urine samples from 66 female chimpanzees from different stages in their reproductive lives also showed that the transition to this post-reproductive state was marked by changes in hormones like gonadotropins, estrogens, and progestins. 

While similar hormonal variations are also a way to tell that this transition is happening in humans, the post-reproductive chimpanzees were not involved in raising their offspring’s children. In these chimpanzees, the common grandmother hypothesis, where females live longer after menopause to help take care of future generations, does not appear to apply. This contrasts with some populations of orca whales, where grandmothers are a critical part of raising their offspring’s young to ensure their survival. 

[Related: Nice chimps finish last—so why aren’t all of them mean?]

According to the team, there are two possible explanations for these longer post-reproductive lifespans. Chimpanzees and other mammals in captivity can have artificially long post-reproductive lifespans because they are protected from natural predators and some pathogens. Even though they’re a wild population, the Ngogo chimpanzees could also be similarly protected and live artificially long lives. They live in a relatively remote area that is undisturbed by logging and hunting by humans and are exposed to fewer human pathogens. Their current habitat could also be closer to what existed in their evolutionary past compared with other populations of primates that are more affected by humans.

“The study both illuminates and raises questions about the evolution of menopause,” University of Exeter evolutionary biologist Michael Cant wrote in a related review on the study. “It also highlights the power of difficult long-term field studies–often run on small budgets and at constant risk of closure–to transform fundamental understanding of human biology and behavior.” Cant is not an author of the study.

Langergraber says future studies like this one could answer the question of how common substantial post-reproductive lifespans have been throughout chimpanzee evolutionary history and if impacts from humans have kept their survivorship rates artificially low.

The post Wild chimpanzees show signs of potential menopause—a rarity in the animal kingdom appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

With its 19 feet-long torpedo-shaped body and long teeth the newly-described Lorrainosaurus was a fearsome mega predator. The fossilized remains of a 170-million-year-old marine reptile is the oldest-known pliosaur and dates back to the Jurassic era. The discovery is described in a study published October 16 in the journal Scientific Reports.

[Related: Millions of years ago, marine reptiles may have used Nevada as a birthing ground.]

Pliosaurs were members of a group of ocean-dwelling reptiles that are closely related to the more famous long-necked plesiosaurs. Unlike their cousins, these pliosaurs had short necks and massive skulls. From snout to tail, it was likely about 19 feet long and very little is known about the plesiosaurs from this time.

“Famous examples, such as Pliosaurus and Kronosaurus–some of the world’s largest pliosaurs–were absolutely enormous with body-lengths exceeding 10m [32 feet]. They were ecological equivalents of today’s killer whales and would have eaten a range of prey including squid-like cephalopods, large fish and other marine reptiles. These have all been found as preserved gut contents,” study co-author and Uppsala University paleontologist Benjamin Kear said in a statement.

Pliosaurs first emerged over 200 million years ago and remained relatively small players in marine ecosystems. Following a landmark restructuring of the marine predator ecosystem in the early to middle Jurassic era (about 175 to 171 million years ago) they reached apex predator status.

“This event profoundly affected many marine reptile groups and brought mega predatory pliosaurids to dominance over ‘fish-like’ ichthyosaurs, ancient marine crocodile relatives, and other large-bodied predatory plesiosaurs,” study co-author and paleobiologist at the Institute of Paleobiology of the Polish Academy of Sciences Daniel Madzia said in a statement.

The fossils in this study were originally found in 1983 in northeastern France, but were recently analyzed by an international team of paleontologists who identified this new pliosaur genus called Lorrainosaurus. The teeth and bones represent what was once a complete skeleton that decomposed and was spread along the ancient seafloor by scavengers and ocean currents. 

[Related: The planet’s first filter feeder could be this extinct marine reptile.]

“Lorrainosaurus was one of the first truly huge pliosaurs. It gave rise to a dynasty of marine reptile mega-predators that ruled the oceans for around 80 million years,” Sven Sachs, a study co-author and paleontologist from the Naturkunde-Museum Bielefeld in Germany, said in a statement.

Other than a short report published in 1994, these fossils remained obscure until the team reevaluated the specimens. Finding Lorrainosaurus’ remains indicates that the reign of gigantic mega-predatory pliosaurs likely began earlier than paleontologists previously thought. These giants were also locally responsive to the major ecological changes in the marine environments that covered present day Europe during the early Middle Jurassic.

“Lorrainosaurus is thus a critical addition to our knowledge of ancient marine reptiles from a time in the Age of Dinosaurs that has as yet been incompletely understood,” said Kear.

The post This Jurassic-era ‘sea murderer’ was among the first of its kind appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Honeybees are a model of teamwork in nature, with their complex society and hives that generate enough energy to create an electrical charge. They also appear to be some of the rare animals that display a unique trait of altruism, which is genetically inherited. The findings were described in a study published September 25 in the journal Molecular Ecology.

[Related: Bee brains could teach robots to make split-second decisions.]

Giving it all for the queen bee

According to the American Psychological Association, humans display altruism through behaviors that benefit another individual at a cost to oneself. Some psychologists consider it a uniquely human trait and studying it in animals requires a different framework for understanding. Animals experience a different level of cognition, so what drives humans to be altruistic might be different than what influences animals like honeybees to act in ways that appear to be altruistic.

In this new study, the researchers first looked at the genetics behind retinue behavior in worker honeybees. Retinue behavior is the actions of worker bees taking care of the queen, like feeding or grooming her. It’s believed to be triggered by specific pheromones and worker bees are always female. 

After the worker bees are exposed to the queen’s mandibular pheromone (QMP), they deactivate their own ovaries. They then help spread the QMP around to the other worker bees and they only take care of the eggs that the queen bee produces. Entomologists consider this behavior ‘altruistic’ because it benefits the queen’s ability to produce offspring, while the worker bees remain sterile. 

The queen is also typically the mother of all or mostly all of the honeybees in the hive. The genes that make worker bees more receptive to the queen’s pheromone and retinue behavior can be passed down from either female or male parent. However, the genes only result in altruistic behavior when they are passed down from the female bee parent.

“People often think about different phenotypes being the result of differences in gene sequences or the environment. But what this study shows is it’s not just differences in the gene itself—it’s which parent the gene is inherited from,” study co-author and Penn State University doctoral candidate Sean Bresnahan said in a statement. “By the very nature of the insect getting the gene from its mom, regardless of what the gene sequence is, it’s possibly going to behave differently than the copy of the gene from the dad.”

A battle of genetics 

The study supports a theory called the Kinship Theory of Intragenomic Conflict. It suggests that a mothers’ and fathers’ genes are in a conflict over what behaviors to support and not support. Previous studies have shown that genes from males can support selfish behavior in mammals, plants, and honeybees. This new study is the first known research that shows females can pass altruistic behavior onto their offspring in their genes. 

[Really: What busy bees’ brains can teach us about human evolution.]

Worker bees generally have the same mother but different fathers, since the queen mates with multiple male bees. This means that the worker bees share more of their mother’s genes with each other. 

“This is why the Kinship Theory of Intragenomic Conflict predicts that genes inherited from the mother will support altruistic behavior in honeybees,” Breshnahan said. “A worker bee benefits more from helping, rather than competing with, her mother and sisters—who carry more copies of the worker’s genes than she could ever reproduce on her own. In contrast, in species where the female mates only once, it is instead the father’s genes that are predicted to support altruistic behavior.”

Pinpointing conflict networks

To look closer, the team crossbred six different lineages of honeybees. Bresnahan says that this is relatively easy to do in mammals or plants, but more difficult in insects. They used honeybee breeding expertise from co-author Juliana Rangel from Texas A&M University and Robyn Underwood at Penn State Extension to create these populations.

Once the bee populations were successfully crossed and the offspring were old enough, the team assessed the worker bees’ responsiveness to the pheromone that triggers the retinue behavior. 

“So, we could develop personalized genomes for the parents, and then map back the workers’ gene expression to each parent and find out which parent’s copy of that gene is being expressed,” Bresnahan said.

The team identified the gene regulatory networks that have this intragenomic conflict, finding that more genes that have a parental bias were expressed. These networks consisted of genes that previous research showed were related to the retinue behavior.

“Observing intragenomic conflict is very difficult, and so there are very few studies examining the role it plays in creating variation in behavior and other traits,” study co-author and Penn State entomologist Christina Grozinger said in a statement. “The fact that this is the third behavior where we have found evidence that intragenomic conflict contributes to variation in honeybees suggests that intragenomic conflict might shape many types of traits in bees and other species.”

The team hopes that this research will help provide a blueprint for more studies into intragenomic conflict in other animals and plants.

The post Female honeybees may pass down ‘altruistic’ genes appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A team of scientists from Spain and the United States reconstructed the skull of an extinct great ape species from a set of well-preserved, but damaged skeletal remains. The bones belonged to Pierolapithecus catalaunicus who lived roughly 12 million years ago. Studying its facial features could help us better understand human and ape evolution and the findings are described in a study published October 16 in the journal Proceedings of the National Academy of Sciences (PNAS).

[Related: This 7th-century teen was buried with serious bling—and we now know what she may have looked like.]

First described in 2004, Pierolapithecus was a member of a diverse group of extinct ape species that lived during the Miocene Epoch (about 15 to 7 million years ago) in Europe. During this time, horses were beginning to evolve in North America and the first dogs and bears also began to appear. The Miocene was also a critical time period for primate evolution.

In the study, the team used CT scans to virtually reconstruct Pierolapithecus’ cranium. They then used a process called principal components analysis and compared their digital reconstruction of the face with other primate species. They then modeled the changes occurring to some key features of ape facial structure. They found that Pierolapithecus shares similarities in its overall face shape and size with fossilized and living great apes. 

However, it also has distinct facial features that have not been found in other apes from the Middle Miocene. According to the authors, these results are consistent with the idea that Pierolapithecus represents one of the earliest members of the great ape and human family. 

“An interesting output of the evolutionary modeling in the study is that the cranium of Pierolapithecus is closer in shape and size to the ancestor from which living great apes and humans evolved,” study co-author and AMNH paleoanthropologist Sergio Almécija said in a statement. “On the other hand, gibbons and siamangs (the ‘lesser apes’) seem to be secondarily derived in relation to size reduction.”

Studying the physiology of extinct animals like Pierolapithecus can help us understand how other species evolved. This particular primate species is important because the team used a cranium and partial skeleton that belonged to the same individual ape, which is a rarity in the fossil record. 

[Related: Our tree-climbing ancestors evolved our abilities to throw far and reach high.]

“Features of the skull and teeth are extremely important in resolving the evolutionary relationships of fossil species, and when we find this material in association with bones of the rest of the skeleton, it gives us the opportunity to not only accurately place the species on the hominid family tree, but also to learn more about the biology of the animal in terms of, for example, how it was moving around its environment,” study co-author Kelsey Pugh said in a statement. Pugh is a primate palaeontologist with the American Museum of Natural History (AMNH) in New York and Brooklyn College.

Earlier studies on Pierolapithecus suggest that it could have stood upright and had multiple adaptations that allowed these hominids to hang from tree branches and move throughout them. However, Pierolapithecus’ evolutionary position is still debated, partially due to the damage to the specimen’s cranium.  

“One of the persistent issues in studies of ape and human evolution is that the fossil record is fragmentary, and many specimens are incompletely preserved and distorted,” study-coauthor and AMNH biological anthropologist Ashley Hammond said in a statement. “This makes it difficult to reach a consensus on the evolutionary relationships of key fossil apes that are essential to understanding ape and human evolution.”

The post 12-million-year-old ape skull bares its fangs in virtual reconstruction appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Sam Kreigman and his colleagues made headlines a few years back with their “xenobots”— synthetic robots designed by AI and built from biological tissue samples. While experts continue to debate how to best classify such a creation, Kriegman’s team at Northwestern University has been hard at work on a similarly mind-bending project meshing artificial intelligence, evolutionary design, and robotics.

[Related: Meet xenobots, tiny machines made out of living parts.]

As detailed in a new paper published earlier this month in the Proceedings of the National Journal of Science, researchers recently tasked an AI model with a seemingly straightforward prompt: Design a robot capable of walking across a flat surface. Although the program delivered original, working examples within literal seconds, the new robots “[look] nothing like any animal that has ever walked the earth,” Kriegman said in Northwestern’s October 3 writeup.

And judging from video footage of the purple multi-“legged” blob-bots, it’s hard to disagree:

After offering their prompt to the AI program, the researchers simply watched it analyze and iterate upon a total of nine designs. Within just 26 seconds, the artificial intelligence managed to fast forward past billions of years of natural evolutionary biology to determine legged movement as the most effective method of mobility. From there, Kriegman’s team imported the final schematics into a 3D printer, which then molded a jiggly, soap bar-sized block of silicon imbued with pneumatically actuated musculature and three “legs.” Repeatedly pumping air in and out of the musculature caused the robots’ limbs to expand and contract, causing movement. During testing, the robot could walk half its body length per second—roughly half as fast as the average human stride.

“It’s interesting because we didn’t tell the AI that a robot should have legs,” Kriegman said. “It rediscovered that legs are a good way to move around on land. Legged locomotion is, in fact, the most efficient form of terrestrial movement.”

[Related: Disney’s new bipedal robot could have waddled out of a cartoon.]

If all this weren’t impressive enough, the process—dubbed “instant evolution” by Kriegman and colleagues—all took place on a “lightweight personal computer,” not a massive, energy-intensive supercomputer requiring huge datasets. According to Kreigman, previous AI-generated evolutionary bot designs could take weeks of trial and error using high-powered computing systems. 

“If combined with automated fabrication and scaled up to more challenging tasks, this advance promises near-instantaneous design, manufacture, and deployment of unique and useful machines for medical, environmental, vehicular, and space-based tasks,” Kriegman and co-authors wrote in their abstract.

“When people look at this robot, they might see a useless gadget,” Kriegman said. “I see the birth of a brand-new organism.”

The post AI design for a ‘walking’ robot is a squishy purple glob appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Neanderthals cooked crab and created art, but they also could have haunted cave lions and used their skins. Some 48,000 year-old puncture wounds on a cave lion’s ribcage suggest that the big cat was killed by a Neanderthal’s wooden spear. The findings are described in a study published October 12 in the journal Scientific Reports and may be the earliest known example of lion hunting and butchering by these extinct humans.

[Related: Sensitive to pain? It could be your Neanderthal gene variants.]

For about 20,000 years, cave lions were the most dangerous animals in Eurasia, with a shoulder height of about 4.2 feet high. They lived in multiple environments and hunted large herbivores including mammoth, bison, hose, and cave bear. They get the name cave lions due to the fact that most of their bones have been found in Ice Age caves. The fearsome creatures went extinct at the end of the last Ice Age, but live on through their bones and the 34,000 rock art panels at Grotte Chauvet in France. 

In 1985, an almost complete cave lion skeleton was uncovered in Siegsdorf, Germany. The bones are believed to be from an old, medium-sized cave lion. There are cut marks across bones including two ribs, some vertebrae, and the left femur, which lead scientists to believe that ancient humans butchered the big cat after it died.  

However, the authors in this new study took another look at the remains. They describe a partial puncture wound located on the inside of the lion’s third rib. The wound appears to match the impact mark left by a wooden-tipped spear. The puncture is angled, which suggests that the spear entered the left of the lion’s abdomen and penetrated its vital organs before impacting the third rib on its right side. 

“The rib lesion clearly differs from bite marks of carnivores and shows the typical breakage pattern of a lesion caused by a hunting weapon,” Gabriele Russo, a study co-author and zooarchaeology PhD student at Universität Tübingen in Germany, said in a statement. 

The characteristics of the puncture wound also resemble the wounds found on deer vertebrae which are known to have been made by Neanderthal spears. The new findings could represent the earliest evidence of Neanderthals purposely hunting cave lions.

“The lion was probably killed by a spear that was thrust into the lion’s abdomen when it was already lying on the ground.” study co-author and University of Reading paleolithic archaeologist Annemieke Milks said in a statement. 

[Related: How many ancient humans does it take to fight off a giant hyena?]

The team also analyzed the findings from a 2019 excavation at the Unicorn Cave–or Einhornhöhle–in the Harz Mountains in Germany. The remains of several animals dating back to the last Ice Age or about 55,000 to 45,000 years ago were found, including some cave lion bones. They looked at bones from the toes and lower limbs of three cave lion specimens. These bones also had cut marks that are consistent with the markings generated when an animal is skinned.

The cut marks suggest that great care was taken while skinning the lion to ensure that the claws remained preserved within the fur. This finding could be the earliest evidence of Neanderthals using a lion pelt, potentially for cultural purposes.

“The interest of humans to gain respect and power from a lion trophy is rooted in Neanderthal behavior and until modern times the lion is a powerful symbol of rulers!” Thomas Terberger, a study co-author and archaeologist at the Universität Göttingen in Germany said in a statement. 

Future studies of cave lion bones could reveal more details of more complex Neanderthal behaviors and how the animal may have laid the basis for cultural development by our own species—Homo sapiens. 

The post Neanderthals may have hunted mighty cave lions appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

In the years since the Neanderthal genome was first sequenced, geneticists have been peering into the past to look for traces of this extinct group of humans within our genes. The presence of these ancient genes could make carriers more at risk for severe COVID-19, influence nose shape, and even make some people more sensitive to pain. 

[Related: Neanderthal genomes reveal family bonds from 54,000 years ago.]

A new study published October 10 in the journal Communications Biology found that those carrying three Neanderthal gene variants are actually more sensitive to pain from skin pricking after prior exposure to mustard oil. In this case, mustard oil acts as an agonist, or a substance that initiates a physiological response. Adding it to the skin causes a quick response by neurons called nociceptors that create a sense of pain. 

SCN9A is a key gene in the perception of pain that is located on chromosome 2. It is highly expressed nociceptors that are activated when a sharp point or something hot is applied to the body. The neurons encode proteins within the body’s sodium channel and alert the brain which leads to the perception of pain. Earlier research found three variations in the SCN9A gene–M932L, V991L, and D1908G–in sequenced Neanderthal genomes and reports of greater sensitivity to pain among the living humans who have all three of these variants. 

“It has been shown in previous studies that some rare mutations in this gene that stop the channel from working can cause insensitivity to pain,” study co-author and University of Oxford neuroscientist David Bennett tells PopSci. “We were, however, interested in these other mutations, which were shown to have an opposite effect of enhancing the activity of this channel, thus leading their carriers to be somewhat more sensitive than non-carriers.”

According to Andrés Ruiz-Linares, study co-author and University College London human geneticist, earlier studies show that the mutations are quite rare in the British populations, but they are very frequent in Latin American populations. 

“We thus realized that we had, in our hands, the perfect dataset to not only replicate their study but also go further and identify the pain modality that was at work here,” Ruiz-Linares tells PopSci. 

In the study, the team measured the pain thresholds of 1,963 individuals from Colombia in response to a range of stimuli. The D1908G variant was present in roughly 20 percent of chromosomes within this population. About 30 percent of chromosomes carrying this variant also carried the M932L and V991L variants. All three variants were associated with a lower pain threshold in response to skin pricking after the skin was exposed to mustard oil, but not in response to pressure or heat. Additionally, carrying all three of these variants was associated with greater pain sensitivity than carrying only one of them. 

[Related: Neanderthals were likely creating art 57,000 years ago.]

The team then analyzed the genomic region that houses SCN9A using genetic data from 5,971 individuals from Peru, Chile, Brazil, Colombia, and Mexico. They found that the three Neanderthal variants were more common in regions where the population had a higher proportion of Native American ancestry, such as the Peruvian population.

“They [the mutations] have a rather wide range in these countries, from 2 to 42 percent,” study co-author and University College London statistical geneticist Kaustubh Adhikari tells PopSci. “Up to 18 percent of their populations could carry two copies of the mutation. These are, however, gross estimations. We also know, from the previous study, that these mutations are pretty rare in European populations.”

The team believes that the Neanderthal variants may sensitize the sensory neurons by changing the threshold at which a nerve impulse is generated. The variants could also be more common in populations with higher proportions of Native American ancestry due to random chance as well as population bottlenecks that occurred during when the Americas were first colonized by Europeans. 

“Although Neanderthal intermixing with Europeans is now well-known in popular culture, their genetic contribution to other human groups, such as Native Americans in this case, is less talked about,” study co-author and population geneticist at the National Research Institute for Agriculture, Food and the Environment in France Pierre Faux tells PopSci. “In this study, we saw how important and relevant it is to study genetic backgrounds that are under-represented in medical cohorts.”

Since acute pain can play a role in moderating behavior and preventing further injury, the team is planning additional research to determine if carrying these variants and having greater sensitivity to pain was advantageous during human evolution. Understanding how these variants work could also help physicians understand and treat chronic pain.

“Genes are just one of many factors, including environment, past experience, and psychological factors, which influence pain,” says Bennet. 

The post Sensitive to pain? It could be your Neanderthal gene variants. appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Meet Garumbatitan morellensis, a new species of large sauropod dinosaur. The Giganotosaurus relative called the present-day Iberian Peninsula home about 122 million years ago. The remains of this titan were discovered in Morella, Spain, and this discovery could help fill in some major evolutionary gaps. The findings were described in a study published September 28 in the journal Zoological Journal of the Linnean Society.

[Related: Cushy feet supported sauropods’ gigantic bodies.]

G. morellensis belongs to the sauropod group of dinosaurs, which includes some well-known favorites like Diplodocus and Brachiosaurus. Sauropods were four-legged Early Jurassic and Cretaceous Era dinos known for their long necks that could reach up to 49 feet long in some species and lengthy tails. G. morellensis is also a member of a subgroup of sauropods known as titanosaurs. These giants were the largest of an already big group and titanosaurs survived right up until the asteroid that wiped out the dinosaurs struck about 66 million years ago.

This new dinosaur’s remains were found and excavated in the Sant Antoni de la Vespa fossil-site in 2005 and 2008. This fossil deposit is home to one of the largest concentrations of sauropod dinosaur remains that date back to the Lower Cretaceous period in Europe (about 145 million to 66 million years ago). Scientists found the remains of a giant unidentified sauropod in Portugal in 2022 that could be Europe’s oldest known dinosaur fossil at 150 million-years-old. 

The team of paleontologists from Portugal and Spain found the remains of three G. morellensis individuals and one other sauropod. Their lucky find included a rare set of footprints. They also uncovered giant vertebrae, leg bones, and two near-complete sets of foot bones. 

“One of the individuals we found stands out for its large size, with vertebrae more than one meter wide [3.2 feet], and a femur that could reach two meters [6.5 feet] in length. We found two almost complete and articulated feet in this deposit, which is particularly rare in the geological record,” study co-author and University of Lisbon paleontologist Pedro Mocho said in a statement. 

G. morellensis was probably close to an average-size titanosaur and could have been near 94 feet long. Its leg shape and foot bones suggest that it was one of the more primitive sauropods from a subgroup called Somphospondyli, according to the authors. Somphospondylan fossils have been found on every present-day continent, but paleontologists are not sure where they originated. This discovery of such an early specimen in Spain points to Europe as a possible origin point for this subgroup, but more evidence is needed.  

[Related: Europe’s largest dinosaur skeleton may have been hiding in a Portuguese backyard.]

This discovery also highlights how complex the evolutionary history of sauropods in the Iberian Peninsula and the rest of Europe is. Species related to these lineages have been found in Asia, North America, and possibly Africa. This points to a potentially long period of dinosaur dispersal within continents and this fossil deposit might fill in some major gaps of evolutionary history. 

“The future restoration of all fossil materials found in this deposit will add important information to understand the initial evolution of this group of sauropods that dominated dinosaur faunas during the last million years of the Mesozoic era,” study co-author and Universidad Nacional de Educación a Distancia in Madrid paleontologist Francisco Ortega said in a statement.

The post A newly discovered sauropod dinosaur left behind some epic footprints appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

In 2006, a cluster of mysterious dark spots on a lakebed of White Sands National Park in New Mexico caught the attention of archaeologists. The shapes stroked their curiosity until they eventually excavated the site three years later. Waiting for them was one of the rarest and soon-to-be controversial discoveries in history—a set of fossilized human footprints. 

The preserved markings were found on the shore of a lake that existed during the most recent ice age, and could be one of the earliest signs of biped migration to North America. Some experts claim they are the steps of the Clovis people, the continent’s first human inhabitants and the ancestors for most Native Americans. The Clovis are thought to have made the journey to North America 13,000 to 13,500 years ago using a land bridge that connected Asia to Alaska. From there, they continued to move as far down south as Central and South America. 

“This was groundbreaking to the archaeologic community, and it was also a tough pill to swallow,” says Kathleen Springer, a research geologist for the United States Geological Survey (USGS) who helped analyze the fossilized steps. “Having 23- to 21,000-year-old footprints is much earlier than the prevailing paradigm of Clovis or pre-Clovis that are known in this part of North America.”

The finding initially received some pushback. When the results were first revealed in 2021, concerned archaeologists wrote comments and papers challenging the results, citing the need for better evidence. More specifically, they criticized the study method and the decision to use radiocarbon dating on the seeds of an aquatic plant that was excavated from the same site. 

Part of the debate came down to an isotope that’s often used in archaeological work. Carbon-14 forms in the air and is introduced to photosynthetic plants and the animals that eat them. When flora and fauna are alive, they have the same amount of carbon-14 as the Earth’s atmosphere; when they die, it decays in their remains. Scientists can then measure how much of the isotope is left and use that metric to calculate an organism’s approximate age. But as some experts have pointed out, aquatic plants like the ones sampled at White Sands can get carbon from the water they live in, which can skew the measurements and make a specimen seem older than it really is.

“It’s called the hard water effect, and it’s a really well-known problem with radiocarbon dating,” explains Jeffrey Pigati, a USGS research geologist who co-authored both studies with Springer. He says the general argument with the first paper is that there were large hard-water effects that made them overestimate the age of the footsteps when they should have been around 15,000 or 17,000 years old.

The COVID pandemic delayed many of the follow-up experiments Pigati and Springer wanted to complete when investigating the site in 2020. Three years later, they finally did with two new methods that corroborate their original estimate of the footprints’ age: radiocarbon dating of pollen and luminescence dating.

To avoid heavy-water effects, the team extracted pollen grains from the same sediment as the White Sands footprints. According to Pigati, this is a time-consuming and laborious process because it involves breaking down rock into one cubic centimeter of material and separating pollen from other organic material before measuring carbon-14 levels. Additionally, pollen is extremely light—experts need to sample thousands of grains to meet the minimum mass requirement for a single radiocarbon measurement. In total, they successfully isolated 75,000 pollen grains. When the they compared the measurements to ones from the seeds of the aquatic plant, the ages matched.

The second technique was optically stimulated luminescence (OSL) dating. Unlike radiocarbon dating, OSL dating is based on the buildup of luminescence properties in quartz crystals over time; in some rare cases, it can date sediments as far back as 400,000 years ago. The USGS team dated three different mineral samples from the same area where the footprint was discovered and calculated ages that were similar to the ones measured in the seeds.

Still, this does not mean we have a complete picture of our species’ migration to North America. Paulette Steeves, an archaeologist and author of The Indigenous Paleolithic of the Western Hemisphere, who was not involved in the White Sands research, says there are archaeological sites in both North and South America that date to as early as 11,000 to 200,000 years ago. While she argues it’s not the oldest sign of human habitation in the Americas and may not be proof of the first Indigenous group, “the White Sands footprints site is a great addition to the record of early people in the Western Hemisphere.”

The footprints are just one piece of the puzzle. Archaeologists still don’t know exactly how people lived in the middle of an ice age and weathered harsh climate. Future projects at White Sands could include tracking the footprints to a campsite or further scouring the area for stone tools that could give some insight into their survival. “Every day we’re working out there is amazing because you never know what is going to be discovered,” Pigati says. “This is all a part of science in action.”

The post Do the ancient human footprints at White Sands date back to the last ice age? appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Over 1,500 animal species, from bonobos to sea urchins to penguins are known to engage same-sex sexual behavior. Still, scientists don’t understand exactly how it came to be or why it happens. While some say the behavior might have existed since the animal kingdom first arose more than half a billion years ago, it may have actually evolved repeatedly in mammals. A study published October 3 in the journal Nature Communications suggests that the behavior possibly plays an adaptive role in social bonding and reducing conflict, and evolved multiple times.

[Related: A massive study confirms no one ‘gay gene’ controls sexual preference.]

The behavior is particularly prevalent in nonhuman primates. It has been observed in at least 51 species from small lemurs up to bigger apes. For one population of male macaques, same-sex sexual behavior may even be a common feature of reproduction and is related to establishing dominance within groups, handling a shortage of different-sex partners, or even reducing tension following aggressive behavior. 

In this new study, the team from institutions in Spain surveyed the available scientific literature to create a database of records of same-sex sexual behavior in mammals. They traced the behavior’s evolution across mammals and tested for any evolutionary relationships with other behaviors. 

The team found that same-sex sexual behavior is widespread across mammal species, occurs in similar frequency in both males and females, and likely has multiple independent origin points. This analysis found that the behavior helps establish and maintain positive social relationships in animals including chimpanzees, bighorn sheep, lions, and wolves.

“It may contribute to establishing and maintaining positive social relationships,” study co-author José Gómez told The New York Times. “With the current data available, it seems that it has evolved multiple times.” Gómez is an evolutionary biologist at the Experimental Station of Arid Zones in Almería, Spain. 

Importantly, they caution that the study should not be used to explain the evolution of sexual orientation in humans. This research focused on same-sex sexual behavior defined as short-term courtship or mating interactions, instead of a more permanent sexual preference. 

Additionally, male same-sex sexual behavior was likely evolved in species with high rates of male adulticide–-when adult animals kill other adults. The team believes that this suggests the behavior may be an adaptation meant to mitigate the risks of violent conflict between males.

Harvard University primatologist Christine Webb, who did not participate in the study, told The Washington Post that the findings add to other research and widen the scope of what it means for a behavior to be considered adaptive.

[Related: Same-sex mounting in male macaques can help them reproduce more successfully.]

“This general question of evolutionary function—that behavior must aid in survival and reproduction—what this paper is arguing is that reaffirming social bonds, resolving conflicts, managing social tensions, to the extent that same-sex sexual behavior preserves those functions—it’s also adaptive,” Webb said. 

Webb also added that it makes sense that other animals would have sex for a variety of reasons the way that humans do.

The authors caution that these associations could also be driven by other evolutionary factors. Same-sex sexual behavior has also only been carefully studied in a minority of mammal species, so our understanding of the evolution of same-sex sexual behavior may continue to change as more mammalian species are studied.

The post Mammals may use same-sex sexual behavior for conflict resolution, bonding, and more appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Parrots are the chatterboxes of the animal kingdom. These famously social birds can learn new sounds throughout their lives and even produce calls that can be individually recognized by other members of their flock. A new study of monk parakeets found that individual birds have a unique tone of voice similar to humans called a “voice print.” The findings are described in a study published October 3 in the journal Royal Society Open Science.

[Related: The next frontier in saving the world’s heaviest parrots: genome sequencing.]

“It makes sense for monk parakeets to have an underlying voice print,” Simeon Smeele, a co-author of the study and biologist studying parrot social and vocal complexity at the Max Planck Institute of Animal Behavior, said in a statement. “It’s an elegant solution for a bird that dynamically changes its calls but still needs to be known in a very noisy flock.”

In humans, our voice print leaves a unique signature in the tone of our voice across every word we say. These voice prints remain even though humans have a very complex and flexible vocal repertoire. Other social animals also use similar cues to recognize one another. Individual dolphins, bats, and birds have a “signature call” that makes them identifiable to other members of their groups. However, signature calls encode identity in only one call type, and there hasn’t been much evidence that suggests animals have unique signatures that last throughout their entire repertoire of calls. 

Parrots use their tongue and mouth to modulate calls similar to the way humans speak. According to Smeele, “their grunts and shrieks sound much more human than a songbird’s clean whistle.” 

Parrots also live in large groups with fluid membership where multiple birds vocalize at the same time. Members need a way to keep track of which individual is making what sound. The question became if the right physical anatomy coupled with the need to navigate complex social lives, helped parrots evolve a voice print. 

In the study, Smeele and his team traveled to Barcelona, Spain—home to the largest population of individually marked parrots in the wild. The parakeets are considered an invasive species and they swarm Barcelona’s parks in flocks with hundreds of members. The Museu de Ciències Naturals de Barcelona has been marking the parakeets for 20 years and have individually identified 3,000 birds.

The team used microphones to record the calls of hundreds of individuals and collected over 5,000 vocalizations in total. They also re-recorded the same individuals over a period of two years, which revealed the stability of the calls over time.

Using a set of computer models, they detected how recognizable individual birds were within each of the five main call types given by this species (contact, tja, trrup, alarm, and growl). They found high variability in the “contact call” that birds use to broadcast their identity. According to the team, this overturned a long-held assumption that contact calls contain a stable individual signal. The new findings suggested that the parakeets are actually using something else for individual recognition.

[Related: These clever cockatoos carry around toolkits to get to food faster.]

To investigate if voice prints were at play, the team used a machine learning model widely used in human voice recognition. The model detects the identity of the speaker using the quality, or timbre, of their voice. The team trained the model to recognize calls of individual birds that were categorized as “tonal” in sound. They then tested to see if the model could detect the same individual from a separate set of calls that were classified as “growling” in sound. The model was able to identify the individual parrots three times better than expected, providing evidence that monk parakeets do actually have a recognizable, individual voice print. 

While exciting, the authors caution that this evidence is still preliminary. Future experiments and analyses could use the parrot tagging work from the team in Barcelona. The GPS devices could help determine how much individuals overlap in their roaming areas.

“This can provide insight into the species’ remarkable ability to discriminate between calls from different individuals,” study co-author and ecologist from Museu de Ciències Naturals de Barcelona Juan Carlos Senar said in a statement.

The post No two parakeets sound exactly the same appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

We all know the line: For more than 150 million years, dinosaurs ruled the Earth. We imagine bloodthirsty tyrannosaurs ripping into screaming duckbills, gigantic sauropods shaking the ground with their thunderous footfalls, and spiky stegosaurs swinging their tails in a reign of reptiles so magnificent, it took the unexpected strike of a six-mile-wide asteroid to end it. The ensuing catastrophe handed the world to the mammals, our ancestors and relatives, so that 66 million years later we can claim to have taken over what the terrible lizards left behind. It’s a dramatic retelling of history that is fundamentally wrong on several counts. Let’s talk about some of the worst rumors and what really happened in the so-called “Age of Dinosaurs.”

Myth: Dinosaurs dominated the planet from their origin.

Fact: Dinosaurs started as cute pipsqueaks.

The oldest dinosaurs we know about are around 235 million years old, from the middle part of the Triassic Period. Those reptiles didn’t rule anything. From recent finds in Africa, South America, and Europe, we know that they were no bigger than a medium-sized dog and were lanky, omnivorous creatures that munched on leaves and beetles. Ancient relatives of crocodiles, by contrast, were much more abundant and diverse. Among the Triassic crocodile cousins were sharp-toothed carnivores that chased after large prey on two legs, “armadillodiles” covered in bony scutes and spikes, and beaked, almost ostrich-like creatures that gobbled up ferns.

Even as early dinosaurs began to evolve into the main lineages that would thrive during the rest of the Mesozoic, most were small and rare compared to the crocodile cousins. The first big herbivorous dinosaurs, which reached about 27 feet in length, didn’t evolve until near the end of the Triassic, around 214 million years ago. But everything changed at the end of the Triassic. Intense volcanic eruptions in the middle of Pangaea altered the global climate; the gases released into the air caused the world to swing between hot and cold phases. By then, dinosaurs had evolved warm-blooded metabolisms and insulating coats of feathers, leaving them relatively unfazed through the crisis, while many other forms of reptiles perished. Had this mass extinction not transpired, we might have had more of an “Age of Crocodiles”—or at least a very different history with a much broader cast of reptilian characters. The only reason the so-called Age of Dinosaurs came to be is because they got lucky in the face of global extinction.

Myth: Dinosaurs spanned the entire planet.

Fact: Dinosaurs never evolved to live at sea.

Of course, these ecosystems were built on a foundation of plankton. Without disc-shaped algae called coccoliths, the rest of the charismatic swimmers of the Triassic, Jurassic, and Cretaceous wouldn’t have thrived. It’s the abundant, small forms of life that let charismatic creatures like marine reptiles prosper—a further reminder that the animals that impress us on land or sea wouldn’t exist without various tiny organisms that set the foundations of food webs. What we might see as dominance, in any ecosystem, is really a consequence of many relationships and interactions that often go unnoticed.

Myth: Dinosaurs suppressed the evolution of mammals.

Fact: Mammals thrived throughout the Age of Dinosaurs.

The classic example of dinosaur dominance is a twitchy little mammal chasing an insect through the Cretaceous night. Dinosaurs would gobble up any beast that got too big or was foolish enough to wander out in the daylight, the argument went, so mammals evolved to be small and nocturnal until the asteroid allowed our ancestors and relatives to emerge from the shadows. The small size and insect-hunting adaptations of some Mesozoic mammals were taken as indicators that mammals were constrained by the success of the dinosaurs, preventing them from becoming larger or opening new niches.

In the past 20 years, however, paleontologists have rewritten the classic story to show that mammals and their relatives thrived alongside the dinosaurs. Throughout the Mesozoic there were furry beasts that swam, dug, glided between the trees, and even ate little dinosaurs. Ancient equivalents of squirrels, raccoons, otters, beavers, sugar gliders, aardvarks, and more evolved through the Jurassic and Cretaceous, including early primates that scampered through the trees over the heads of T. rexes. While it’s true that all the Mesozoic mammals we presently know of were small—the largest was about the size of an American badger— researchers have realized that the way our ancient ancestors interacted with each other was much more important to shaping their evolution than the dinosaurs were. In fact, even with the dinosaurs gone, most new mammal species stuck to being small. We get so hung up on size that we’ve missed the real story, closer to the ground.

Myth: Dinosaurs dominated the planet for millions of years.

Fact: No single species can dominate a planet.

The post 4 reasons dinosaurs never really ruled the Earth appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Sea turtles have been around for at least 110 million years, yet relatively little is known about their evolution. Two of the most common sea turtles on Earth are olive ridley and Kemp’s ridley turtles that belong to a genus called Lepidochelys that could help fill in some of the gaps of sea turtle biology and evolution. A team of paleontologists not only discovered the oldest known fossil of turtle from the Lepidochelys genus, but also found some traces of ancient turtle DNA. The findings are detailed in a study published September 28 in the Journal of Vertebrate Paleontology.

[Related: 150 million-year-old turtle ‘pancake’ found in Germany.]

The DNA comes from the remains of a turtle shell first uncovered in 2015 in the Chagres Formation on Panama’s Caribbean coast. It represents the oldest known fossil evidence of Lepidochelys turtles. The turtle lived approximately 6 million years ago, curing the upper Miocene Epoch. At this time, present day Panama’s climate was getting cooler and drier, sea ice was accumulating at Earth’s poles, rainfall was decreasing, sea levels were falling.

“The fossil was not complete, but it had enough features to identify it as a member of the Lepidochelys genus,” study co-author and Universidad del Rosario in Bogotá, Colombia paleontologist Edwin Cadena tells PopSci. Cadena is also a research associate at the Smithsonian Tropical Research Institute in Panama.

The team detected preserved bone cells called osteocytes. These bone cells are the most abundant cells in vertebrates and they have nucleus-like structures. The team used a solution called DAPI to test the osteocytes for genetic material.

“In some of them [the osteocytes], the nuclei were preserved and reacted to DAPI, a solution that allowed us to recognize remains of DNA. This is the first time we have documented DNA remains in a fossilized turtle millions of years old,” says Cadena.

According to the study, fossils like this one from vertebrates preserved in this part of Panama are important for our understanding of the biodiversity that was present when the Isthmus of Panama first emerged roughly 3 million years ago. This narrow strip of land divided the Caribbean Sea and the Pacific Ocean and joined North and South America. It created a land bridge that made it easier for some animals and plants to migrate between the two continents.

[Related: Hungry green sea turtles have eaten in the same seagrass meadows for about 3,000 years.]

This specimen could also have important implications for the emerging field of molecular paleontology. Scientists in this field study ancient and prehistoric biomatter including proteins, carbohydrates, lipids, and DNA that can sometimes be extracted from fossils. 

Molecular paleontology aims to determine if scientists can use this type of evidence to determine more about the organisms than their physical shape, which is typically what is preserved in most fossils. Extracting this tiny material from bones was critical in sequencing the Neanderthal genome, which earned Swedish scientist Svante Pääbo the 2022 Nobel prize in physiology or medicine.

“Many generations have grown up with the idea of extracting and bringing back to life extinct organisms,” says Cadena. “However, that is not the real purpose of molecular paleontology. Instead, its goal is to trace, document, and understand how complex biomolecules such as DNA and proteins can be preserved in fossils.”

This new turtle specimen could help other molecular paleontologists better understand how soft tissues can be preserved over time. It could also shift the idea that original biomolecules like proteins or DNA have a specific timeline for preservation in fossils and encourage re-examining older specimens for traces of biomolecules. 

The post This 6-million-year-old turtle shell still has some DNA appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

One of the most enduring mysteries about our earliest ancestors and extinct human relatives is how they ate and procured enough food to sustain themselves millions of years ago. We believe that archery first arrived in Europe about 54,000 years ago and Neanderthals were cooking and eating crab about 90,000 years ago, but scavenging was likely necessary to get a truly hearty meal. A modeling study published September 28 in the journal Scientific Reports found that groups of hominins roughly 1.2 to 0.8 million years ago in southern Europe may have been able to compete with giant hyenas for carcasses of animals abandoned by larger predators like saber-toothed cats.

[Related: An ‘ancestral bottleneck’ took out nearly 99 percent of the human population 800,000 years ago.]

Earlier research has theorized that the number of carcasses abandoned by saber-toothed cats may have been enough to sustain some of southern Europe’s early hominin populations. However, it’s been unclear if competition from giant hyenas (Pachycrocuta brevirostris) would have limited hominin access to this food source. These extinct mongoose relatives were about 240 pounds–roughly the size of a lioness–and went extinct about 500,000 years ago. 

“There is a hot scientific debate about the role of scavenging as a relevant food procurement strategy for early humans,” paleontologist and study co-author Jesús Rodríguez from the National Research Center On Human Evolution (CENIEH) in Burgos, Spain tells PopSci. “Most of the debate is based on the interpretation of the scarce and fragmentary evidence provided by the archaeological record. Without denying that the archaeological evidence should be considered the strongest argument to solve the question, our intention was to provide elements to the debate from a different perspective.”

For this study, Rodríguez and co-author Ana Mateos looked at the Iberian Peninsula in the late-early Pleistocene era. They ran computer simulations to model competition for carrion–the flesh of dead animals–between hominins and giant hyenas in what is now Spain and Portugal. They simulated whether saber-toothed cats and the European jaguar could have left enough carrion behind to support both hyena and hominin populations—and how this may have been affected by the size of scavenging groups of hominins. 

They found that when hominins scavenged in groups of five or more, these groups could have been large enough to chase away giant hyenas. The hominin populations also exceeded giant hyena populations by the end of these simulations. However, when the hominins scavenged in very small groups, they could only survive to the end of the simulation when the predator density was high, which resulted in more carcasses to scavenge.  

[Related: Mysterious skull points to a possible new branch on human family tree.]

According to their simulations, the potential optimum group size for scavenging hominins was just over 10 individuals. This size was large enough to chase away saber-toothed cats and jaguars. However, groups of more than 13 individuals would have likely required more carcasses to sustain their energy expenditure. The authors caution that their simulations couldn’t specify this exact “just right” group size, since the numbers of hominins needed to chase away hyenas, saber-toothed cats, and jaguars were pre-determined and arbitrarily assigned.

“The simulations may not determine the exact value of the optimum, but show that it exists and depends on the number of hominins necessary to chase away the hyenas and of the size of the carcasses,” says Rodríguez.

Scavenged remains may have been an important source of meat and fat for hominins, especially in winter when plant resources were scarce. This team is working on simulating the opportunities hominins had for scavenging in different ecological scenarios in an effort to change a view that scavenging is marginal and that hunting is a more “advanced” and more “human” behavior than scavenging. 

“The word for scavenger in Spanish is ‘carroñero.’ It has a negative connotation, and is frequently used as an insult. We do not share that view,” says Rodríguez. “Scavengers play a very important role in ecosystems, as evidenced by the ecological literature in the last decades. We view scavenging as a product of the behavioral flexibility and cooperative abilities of the early hominins.”

The post How many ancient humans does it take to fight off a giant hyena? appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Scientists in Thailand have discovered a new species of tarantula with a very unique blue hue. The tarantula is named Chilobrachys natanicharum and is also called the electric blue tarantula. The findings were described in a study published September 18 in the journal ZooKeys 

[Related: Before spider mites mate, one of them gets their skin removed.]

The new colorful arachnid was discovered in southern Thailand’s Phang-Nga province. It follows the identification of another new species of tarantula called Taksinus bambus, or the bamboo culm tarantula.

“In 2022, the bamboo culm tarantula was discovered, marking the first known instance of a tarantula species living inside bamboo stalks,” study co-author and Khon Kaen University entomologist Narin Chomphuphuang said in a statement. “Thanks to this discovery, we were inspired to rejoin the team for a fantastic expedition, during which we encountered a captivating new species of electric blue tarantula.”

The team that found the first not-so-blue bamboo culm tarantula included a local wildlife YouTuber named JoCho Sippawat. This year, Chomphuphuang joined up with Sippawat for a surveying expedition in the province to learn more about tarantula diversity and distribution. They identified this new species by this very distinctive coloration during the expedition.

“The first specimen we found was on a tree in the mangrove forest. These tarantulas inhabit hollow trees, and the difficulty of catching an electric-blue tarantula lies in the need to climb a tree and lure it out of a complex of hollows amid humid and slippery conditions,” Narin said. “During our expedition, we walked in the evening and at night during low tide, managing to collect only two of them.”

The color blue is very rare in nature. It can even exist in other animals that aren’t usually this color, including the blue lobsters that have recently been found in Massachusetts and France. Some animals also evolved wild colors including blues, yellows, and reds to appear poisonous to try and keep other animals from eating them.  

In order for an organism to appear blue, it must absorb very small amounts of energy while reflecting high-energy blue light. Since penetrating molecules that are capable of absorbing this energy is a complex process, the color blue is less common than other colors in the natural world. 

According to the study, the secret behind the electric blue tarantula’s wild color comes from the unique structure of their hair and not from a presence of blue pigment. Their hair incorporates nanostructures that manipulate the light shining on it to create the blue appearance. Their hair can also display a more violet hue depending on the light, which creates an iridescent effect. 

[Related: Blue-throated macaws are making a slow, but hopeful, comeback.]

This species was previously found on the commercial tarantula market, but there hadn’t been any documentation describing its natural habitat or unique features. 

“The electric blue tarantula demonstrates remarkable adaptability. These tarantulas can thrive in arboreal as well as terrestrial burrows in evergreen forests,” Narin said. “However, when it comes to mangrove forests, their habitat is restricted to residing inside tree hollows due to the influence of tides.”

To name the new species, the authors conducted an auction campaign and the scientific name of Chilobrachys natanicharum was selected. It is named after executives Natakorn and Nichada Changrew of Nichada Properties Co., Ltd., Thailand and the proceeds of the auction were donated to support the education of Indigenous Lahu children in Thailand and for cancer patients in need of money for treatment.

The authors say that this discovery points to the continued importance of taxonomy as a basic aspect of research and conservation. It also highlights the need to protect mangrove forests from continued deforestation, as the electric blue tarantula is also one of the world’s rarest tarantulas. 

“This raises a critical question: Are we unintentionally contributing to the destruction of their natural habitats, pushing these unique creatures out of their homes?” the researchers ask in their conclusion.

The post Meet the first electric blue tarantula known to science appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Parasitic plants make up about 1 percent of flowering species within the plant kingdom and their quirks and tricks continue to come with surprises. Some parasitic plants are now potentially evolving to be so dependent on their host plants, that they are losing sizable amounts of genomes related to basic biological processes like photosynthesis. The findings are described in a study published September 21 in the journal Nature Plants.

[Related: How a peculiar parasitic plant relies on a rare Japanese rabbit.]

Plants in the Balanophoraceae family that are found in tropical and temperate regions in Asia and tropical Africa generally resemble fungi growing around the roots of trees in the forest, but there is a lot more than meets the eye. The structures that look like mushrooms are instead inflorescences, or a cluster of flowers intricately arranged on a stem.  

However, unlike other parasitic plants that extend a skinny projection called a haustorium into a host’s tissue to steal its nutrients, plants in the Balanophora genus actually induce their host plant’s vascular system to grow into a tuber to store nutrients. This forms a unique underground organ made from tissue of both the host plant that Balanophora then uses to eat..

To learn more about how these subtropical extreme parasitic plants evolved into this unique form, a team from the Beijing Genomics Institute (BGI) and the University of British Columbia compared Balanophora’s genomes with another parasitic plant genus called Sapria that has a very different vegetative body. Sapria are members of the family Rafflesiaceae, including some very smelly corpse flowers, and can generally be found in tropical forests of Asia.

The study found that Sapria has lost 38 percent of its genomes and Balanophora has lost 28 percent of their genomes over time, while evolving their parasitic behaviors, which the authors say is a record genetic shrinking for flowering plants.

“The extent of similar, but independent gene losses observed in Balanophora and Sapria is striking,” study co-author and BGI Research plant geneticist Xiaoli Chen said in a statement. “It points to a very strong convergence in the genetic evolution of holoparasitic lineages, despite their outwardly distinct life histories and appearances, and despite their having evolved from different groups of photosynthetic plants.”

They found that both Balanophora and Sapria have even lost almost all of the genes associated with photosynthesis and other key biological processes, including nitrogen absorption, root development, and the regulation of flower development. 

“The majority of the lost genes in Balanophora are probably related to functions essential in green plants, which have become functionally unnecessary in the parasites,” study co-author and University of British Columbia botanist Sean Graham said in a statement.

[Related: We’re finally figuring out how plants pass on genetic memories.]

Since these parasitic plants don’t necessarily need to rely on sunlight and water to make food through photosynthesis and instead use the resources of their host plants, they appear to be losing those genes. 

Notably, the genes related to the synthesis of a major hormone responsible for plant stress responses and signaling called abscisic acid (ABA) have also been lost in Balanophora and Sapria. Even with the loss, the team still recorded a build up of the ABA hormone in Balanophora’s flowering stems and saw that genes involved in the response to ABA signaling are still retained in the parasites. According to the team, this gene loss could be beneficial to the plant. 

“The loss of their entire ABA biosynthesis pathway may be a good example. It may help them to maintain physiological synchronization with the host plants,” said Graham. “This needs to be tested in the future.”

The team says that this study deepens the major genomic alterations occurring within parasitic plants and is important in the context of a project working to sequence the genomes of 10,000 plant species called 10KP.

The post These parasitic plants force their victims to make them dinner appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Just in time for spooky season, scientists have learned more about how a tiny parasitic flatworm called the lancet liver fluke infects and controls the brains of ants. With their complex four-step cycle, the flukes could be cunningly adjusting to daily changes in air temperatures to infect more hosts. The findings were recently published in the journal Behavioral Ecology.

[Related: Mind-controlling ‘zombie’ parasites are real.]

Step 1: The Zombie Ant

The parasite hijacks an ant’s brain after an ant eats a ball of snail mucus infested with fluke larvae. The larvae then mature inside the brain, where the parasite can make the ant climb up a blade of grass and clamp down on the blade. This strategic height makes it easier for the parasite’s next potential host—a cow, sheep, deer, or other grazer—to eat the flukes and offer it another place to live and breed. This new study found that the liver fluke can even get the ant to crawl back down the blade of grass when it gets too hot.

“Getting the ants high up in the grass for when cattle or deer graze during the cool morning and evening hours, and then down again to avoid the sun’s deadly rays, is quite smart. Our discovery reveals a parasite that is more sophisticated than we originally believed it to be,” University of Copenhagen biologist and study co-author Brian Lund Fredensborg said in a statement. Fredensborg conducted the research with his former graduate student Simone Nordstrand Gasque, now a PhD student at Wageningen University in the Netherlands.

In their study, the team tagged several hundred infected ants in the Bidstrup Forests near Roskilde, Denmark. “It took some dexterity to glue colors and numbers onto the rear segments of the ants, but it allowed us to keep track of them for longer periods of time,” said Fredensborg.

The team observed how the infected ants behaved to humidity, light, time of day, and temperature and it was clear that temperature has an effect on their behavior. During cooler temperatures, the ants were more likely to be attached to the top of a blade of grass. When the temperature rose, the ants let go of the grass and crawled back down. 

“We found a clear correlation between temperature and ant behavior,” said Fredensborg. “We joked about having found the ants’ zombie switch,’”

Step 2: The Grazer

Once the liver fluke infects the ant, several hundred parasites invade the insect’s body. Only one of these parasites will make it to the brain where it then influences the ant’s behavior. The remaining liver flukes conceal themselves in the ant’s abdomen inside of its intestine. There, the liver flukes find their way through the bile ducts and into the liver, where they suck blood and develop into adult flukes that begin to lay eggs. 

[Related: ‘Brainwashing’ parasites inherit a strange genetic gap.]

“Here, there can be hundreds of liver flukes waiting for the ant to get them into their next host. They are wrapped in a capsule which protects them from the consequent host’s stomach acid, while the liver fluke that took control of the ant, dies. You could say that it sacrifices itself for the others,” said Fredensborg. 

The eggs are then excreted in the host animal’s feces.

Step 3: The Snail

Once the fluke eggs have been excreted, they remain on the ground waiting for a snail to crawl by and eat the feces. When the eggs are inside the snail, the eggs develop into larval flukes that reproduce asexually and can multiply into several thousand. 

“Historically, parasites have never really been focused on that much, despite there being scientific sources which say that parasitism is the most widespread life form,” said Fredensborg. “This is in part due to the fact that parasites are quite difficult to study.”

Step 4: The Slime Ball

To exit the snail and move on to their next host, the larval flukes make the snail cough. The flukes are then expelled from the snail in a lump of mucus. The ants are attracted to this moist ball, eat it, and unwittingly ingest more fluke larvae and the cycle begins all over again.

The tiny liver fluke is widespread in Denmark and other temperate regions around the world and researchers are still trying to understand more of the mechanisms behind how they take over a host’s brain. 

“We now know that temperature determines when the parasite will take over an ant’s brain. But we still need to figure out which cocktail of chemical substances the parasite uses to turn ants into zombies,” Fredensborg said. “Nevertheless, the hidden world of parasites forms a significant part of biodiversity, and by changing the host’s behavior, they can help determine who eats what in nature. That’s why they’re important for us to understand.”

The post This parasite deploys mucus slime balls to make ‘zombie ants’ appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Dinosaur Mysteries digs into the secretive side of the “terrible lizards” and all the questions that keep paleontologists up at night.

WE STILL LIVE in an age of dinosaurs. Pigeons, penguins, and partridges are all members of the only lineage to survive the asteroid-driven disaster of 66 million years ago. The realization that at least some dinosaurs still flock among us has given a greater depth to paleontology than the field’s founders could have imagined. What we learn about living dinosaurs can help us better understand the species we can touch only as fossils. But even though we can trace the origins of birds from their Velociraptor-like ancestors, there’s one critical part of the story that we don’t fully understand. How on earth did dinosaurs such as Microraptor evolve the ability to fly?

The definition of flight can be a little tricky—it’s not simply about moving through the air. After all, there are marsupials, frogs, snakes, and other animals capable of gliding for impressive distances. Flight is something more specific, requiring the evolution of not only wings but a wing stroke. Watch a raven flap by and you’re watching a dinosaur demonstrate the exact mechanics of keeping itself aloft with one wingbeat after another. The question paleontologists face is how dinosaurs went from terrestrial reptiles scurrying over the ground to feathery, fluttering wonders.

Archaeopteryx lithographica, the earliest recognized bird at about 150 million years old, is of limited help. When the fossil was uncovered in the late 19^th century, the splash of feathers found around the Jurassic dinosaur’s bones were quickly taken as an indication that its kind soared over the forests of prehistoric Bavaria. Over time, however, the genus Archaeopteryx started to look more awkward than aerodynamic. The avian ancestor had asymmetrical flight feathers with a shallow leading edge, a critical adaptation for powered flight—but its skeletal anatomy didn’t look capable of flight the way we see it in living birds. The contradiction led to a longstanding debate over whether Archaeopteryx actively flapped into the air, primarily glided, or perhaps even used a different flight stroke from its modern relatives. Whatever the answer, the solution to the mystery can’t be found in its bones alone. And as further feathery dinosaur species have been uncovered, the caper has only grown more complex.

Since the mid-1990s, paleontologists have uncovered dozens of feathery dinosaurs. Many of them are close relatives of Mesozoic birds or otherwise have adaptations related to flight, including the genus Microraptor, which had long feathers on its legs as well as its long arms. In fact, paleontologists think powered flight evolved at least three times among dinosaurs: once among birds and twice among their close dinosaur relatives such as Rahonavis ostromi. That’s not counting the number of feathery species whose anatomy made them more aerodynamically adept than others, but that still weren’t quite capable of keeping themselves aloft by flapping. Instead of a neat, orderly pattern of flight-related traits among birds and their ancestors, the emerging picture shows a tangled mess.

That changes the entire backstory of flying beasts. Up until recently, feathery dinosaurs were cast as representatives of stages in the evolution of flight. Now paleontologists have to figure out how they evolved flight independently multiple times among both birds and feathery nonavian dinosaurs. The path the ancestors of Archaeopteryx took might not be the same as the path taken by predecessors of Microraptor or Rahonavis.

Experts have tossed plenty of ideas about the origins of flight against the proverbial wall. These are broadly divided into “ground-up” and “trees-down” hypotheses, with most paleontologists favoring explanations that focus on how a ground-dwelling, Velociraptor-esque avian ancestor could evolve the ability to fly. Maybe feathery bird ancestors chased insects, leaping after them and trying to trap them with their arm feathers, which would favor dinosaurs able to stay in the air longer. Or maybe flight started with gliding and dinosaurs climbing trees to swoop through the forest, which would give an advantage to those that could flap their arms to soar just a little farther. The behavior of modern birds has provided some clues too, like the way chukar partridges flap their wings to better stabilize themselves while running up inclines.

Every hypothesis about how airborne dinosaurs evolved focuses on the behavior of animals we can’t observe in life. Experts have to draw out what clues they can from feathers, bones, the universal mechanics of flight, and how birds today manage to get into the air and stay there. While it’s possible to conduct wind-tunnel experiments based on skeletal mechanics and other inferred details to calculate how an Archaeopteryx would have fared while flying, there will always be a difference between what a prehistoric species could have done and how it actually behaved back in the Mesozoic. Evolution is not a tidy progression towards a particular outcome, but a story of constant change full of repeats, dead ends, and diversity.

There can’t be a single solution to the puzzle of how dinosaurs evolved to fly because scientists have more than one case to consider. Whether it consists of birds or nonavian dinosaurs, the history of each lineage has to be studied on its own terms. More than that, what seemed like a basic question about the first flying dinosaurs only creates more questions about what led different dinosaurs in different places and times, many miles and millions of years apart, to evolve similar abilities. Pterosaurs—fuzzy, flying reptiles that were related to dinosaurs—reigned over the skies more than 50 million years before Archaeopteryx, so it’s not as if Earth weren’t already full of fliers before dinosaurs caught on. The stories we now deduce of how flying dinosaurs gained their astonishing ability are far more complex than the ones we had even 20 years ago. When you see a house finch alight on a feeder or a turkey vulture slowly turn over a thermal, you’re catching a glimpse of one of the greatest secrets still cached in the fossil record.

Read more PopSci+ stories.

The post We still don’t know how animals evolved to fly appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Space tourism is already becoming so commonplace that Virgin Galactic’s second private astronaut flight on September 8 went off without much fanfare. And although a brief press announcement only announced the names of its three-man passenger list after the trip, the recap didn’t mention Galactic 03’s historic “first” cargo—fossilized bones from two of humanity’s closest ancestors.

According to Tim Nash’s Virgin Galactic biography, the “entrepreneur, adventurer, conservationist and member of the Hubbard Council of The National Geographic Society,” carried with him the clavicle of a nearly 2-million-year-old Australopithecus sediba, as well as a roughly 250,000-year-old thumb bone from Homo naledi. Both hominid remains were previously discovered within the Cradle of Humankind UNESCO World Heritage Site outside Johannesburg, South Africa—sebedi is considered one of the potential candidates that presaged humanity’s Homo genus.

The initiative’s organizers, including researchers at the University of Witwatersrand, Johnnesburg, intended the gesture to represent “humankind’s appreciation of the contribution of all of humanity’s ancestors and our ancient relatives,” said Lee Berger, a National Geographic Explorer in Residence, Carnegie Fellow and Director of the Centre for the Exploration of the Deep Human Journey. “Without their invention of technologies such as fire and tools, and their contribution to the evolution of the contemporary human mind, such extraordinary endeavors as spaceflight would not have happened.”

[Related: Virgin Galactic’s second commercial flight sent three tourists to space’s edge.]

Berger’s son, Matthew, discovered the sebida clavicle in 2008 when he was 9 years old during an expedition alongside his father within the Cradle of Humankind heritage site. Matthew Berger traveled last week to Virgin Galactic’s Spaceport America in New Mexico to hand deliver the bones to Nash, a conservationist involved with human origins research. Caretakers stored both bone fragments within a carbon fiber container prior to their suborbital excursion.

“These fossils represent individuals who lived and died hundreds of thousands of years ago, yet were individuals who likely gazed up at the stars in wonder, much as we do,” Berger said in a September 8 statement via the University of Witwatersrand.

“The magnitude of being among the first civilians going into space, and carrying these precious fossils, has taken a while to sink in, during all of the preparations for the flight,” Nash said via the University of Witwatersrand statement, “But I am humbled and honored to represent South Africa and all of humankind, as I carry these precious representations of our collective ancestors, on this first journey of our ancient relatives into space.”

Nash, alongside Las Vegas real estate entrepreneur Ken Baxter and British engineer and racecar company founder Adrian Reynald, purchased their Virgin Galactic seats as far back as 2004 from company founder and multibillionaire Richard Branson. Tickets for the few minutes’ worth of suborbital weightlessness alongside views of the Earth’s curvature reportedly cost between $250,000 and $450,000.

“We sincerely hope it brings further awareness of the importance of our country and the African continent to understanding the journey of humankind that has led to this historic moment where commercial spaceflight is possible,” says Cradle of Humankind World Heritage Site CEO Matthew Sathekge said via University of Witwatersrand’s announcement.

The post Virgin Galactic’s latest cargo? Ancient human bones appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

The lives of corvid, or the family of birds that include crows, are shockingly complex. They hold ‘monogamish’ relationships, build tools, hold funerals, solve puzzles, and may even have their own form of democracy. Now, researchers have provided the latest peek into corvid life that adds a new element to their intricate and complicated lives—social climbing. Yes, even birds will ditch their old friends if something better comes along, according to a new study published September 11 in Nature.

For their recent experiment, scientists at universities of Exeter and Bristol utilized the Cornish Jackdaw Project to split a group of jackdaws, members of the crow family found in Europe, western Asia and North Africa, into two randomly sorted groups—A and B. They then tagged the birds with transponder chips, worn like little anklets, to tell who was who. 

[Related: Crows and ravens flexed smarts and strength for world dominance.]

As many animal studies go, there’s got to be some kind of snack involved. This time, the scientists set up a feeding source with two locked doors—one filled with grain, a merely okay morsel for a hungry crow, and the other with a much yummier rendition of some grain and some dried mealworms. If a bird visited alone, only the low-quality snack door opened. With a buddy from the same-tagged group, say two As or two Bs, either both doors unlocked or just the high-quality snack door. But when a jackdaw visited the snack dispenser with a member of the opposite-tagged clique, there were no goodies for anybody.

The choice for the birds then was either loyalty or tasty treats. 

“The jackdaws turned out to be very strategic, quickly learning to hang out with members of their own group and ditching old ‘friends’ from the other group so they could get the best rewards,” author Alex Thornton, a professor of cognitive evolution at Exeter, said in a release.

The same couldn’t always be said for familial relationships. Despite the potentially disappointing outcome, jackdaws would still stick with their offspring, siblings, or mating partners. Some long-term relationships, it turns out, were more important to the feathery creatures than a chance at a delicious morsel. 

“The fundamental idea is that if you need to keep track of interactions you have had with other individuals, remember the outcomes of those interactions and use those to adjust your [behavior],” Thornton told the Guardian. “What we were able to do here was test the idea: can individuals keep track of the outcomes of past interactions and update their relationships. It turns out they can.”

For the authors, these results can give us clues to the evolution of intelligence, memory, and social status in the animal kingdom—and even in the human world. 

“Our findings also help us to understand how societies emerge from individual decisions,” author and Exeter PhD student Josh Arbon said in a release. “The balance between strategically playing the field for short-term benefits and investing in valuable long-term partners ultimately shapes the structure of animal societies, including our own.”

The post These crow relatives put food over friendship appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Australia is currently home to the only living species of their endangered and iconic koalas, but there once were multiple species spread across the continent. Now, the discovery of another marsupial ancient relative is helping scientists fill in a 30 million year evolutionary gap. The findings are detailed in a study published September 4 in the journal Scientific Reports.

[Related: With bulging eyes and a killer smile, this sabertooth was an absolute nightmare.]

In 2014 and 2020, study co-author Arthur Crichton, a PhD student at Flinders University in Adelaide, Australia, found fossil teeth of the new species, named Lumakoala blackae, at the Pwerte Marnte Marnte fossil site in central Australia. The teeth are believed to be roughly 25 million years old. 

“Our computer analysis of its evolutionary relationships indicates that Lumakoala is a member of the koala family (Phascolarctidae) or a close relative, but it also resembles several much older fossil marsupials called Thylacotinga and Chulpasia from the 55 million-year-old Tingamarra site in northeastern Australia,” Crichton said in a statement. 

According to Chrichton, it was previously suggested that the enigmatic Thylacotinga and Chulpasia may have been more closely related to marsupials from South America.  This new discovery of Lumakoala suggests that they could actually be early relatives of herbivorous Australian marsupials including possums, kangaroos, koalas, and wombats.

“This group (Diprotodontia) is extremely diverse today, but nothing is known about the first half of their evolution due to a long gap in the fossil record,” said Crichton. 

If the study’s hypothesis is correct, the diprotodontian fossil record would be aged back by another 30 million years. Additionally, wombats, kangaroos, koalas and possums split off from other marsupials between roughly 65 million and 50 million years ago.

“These Tingamarran marsupials are less mysterious than we thought, and now appear to be ancient relatives of younger, more familiar groups like koalas,” Robin Beck, study co-author and evolutionary biologist at the University of Salford in England, said in a statement. “It shows how finding new fossils like Lumakoala, even if only a few teeth, can revolutionize our understanding of the history of life on Earth.” 

The study also raises some new questions, including whether these relatives of herbivorous marsupials in Australia once lived in Antarctica and South America. According to Beck, some South American fossils look very similar to the marsupials found at the Tingamarra site. 

[Related: This 500-pound Australian marsupial had feet made for walkin.’]

It also reports that two other types of koala called Madakoala and Nimiokoala lived alongside Lumakoala and filled in different ecological niches in the forests that flourished in central Australia about 25 million years ago. The late Oligocene (about 23–25 million years ago) was  “kind of the koala heyday,” according to the Flinders University paleontologist and study co-author Gavin Prideaux.

“Until now, there’s been no record of koalas ever being in the Northern Territory; now there are three different species from a single fossil site,” Prideaux said in a statement. “While we have only one koala species today, we now know there were at least seven from the late Oligocene – along with giant koala-like marsupials called ilariids.”  

At this time, iliariids were the largest marsupials living in Australia, weighing in at up to 440 pounds. Iliariids lived alongside a strong-toothed wombat relative named Mukupirna fortidentata and a strange possum named Chunia pledgei.

The post Scientists discover a cat-sized ancient koala in Australia appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A newly discovered early bird-like dinosaur species is filling in some of the holes in the dinosaur-to-bird evolutionary story. The new species, named Fujianvenator prodigiosus, has a strange mixture of physical features shared with other extinct prehistoric animals from therapod dinosaurs to birdlike troodontids. This unique beast was described in a study published September 6 in the journal Nature. 

[Related: Birds are dinosaurs, and this fossil detective has rooms full of bones to prove it.]

Birds diverged from theropod dinosaurs by the Late Jurassic (about 161 million to 146 million years ago), but the general understanding of the earliest evolution of the clade comprising most modern birds, known as Avialae, has been slowed due to a limited diversity of fossils from the Jurassic. No known avialans have been reported from the Yanliao Biota paleontological site in northeast China, which dates back to the Middle–Late Jurassic about 166–159 million years ago or in the the slightly younger German Solnhofen Limestones, which preserves an early genus of avian dinosaurs called Archaeopteryx. This leaves a gap of about 30 million years before the oldest known record of Cretaceous birds. 

Jurassic era avialans are a critical key to deciphering the evolutionary origin of the avialan body,  and this elusive group is key to piecing together the origin of birds. That’s where the fossilized remains of the 148 to 150-million-year-old avialan theropod Fujianvenator prodigiosus comes in. It has some physical traits shared with extinct avialans, the small and bird-like troodontids that lived during the Cretaceous Period, and theropod dinosaurs called dromaeosaurids that were similar to raptors and also lived during the Cretaceous. According to the team on this study, this mixture shows the impact of evolutionary mosaicism–different rates of evolutionary change in body structures and function– in early bird evolution.

A joint research team from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences in Beijing and the Fujian Institute of Geological Survey (FIGS) described and the avialan theropod that was found in Zhenghe County, Fujian Province in southeastern China.

“Our comparative analyses show that marked changes in body plan occurred along the early avialan line, which is largely driven by the forelimb, eventually giving rise to the typical bird limb proportion,” study co-author and paleontologist Min Wang from IVPP said in a statement. “However, Fujianvenator is an odd species that diverged from this main trajectory and evolved bizarre hindlimb architecture.”

[Related: Birds are so specialized to their homes, it shows in their bones.]

During the Late Jurassic-Early Cretaceious, southeastern China saw some intense tectonic activities that resulted in a lot of movement of magma below the Earth’s surface. This created some deep basins with the Earth including where Fujianvenator was found.

Fujianvenator prodigiosus was likely about the size of a present day pheasant and had a tibia (lower leg) that is twice as long as its femur (thigh), which is a previously unknown condition for non-avian dinosaurs. This suggests that the bird was either a high-speed runner or a long-legged wader and it likely lived in swamps. This new finding contrasts with other early avialans, which are believed to have been more tree and sky-dwelling.  

Fujianvenator’s remains were found among a diverse collection of vertebrate fossils dominated by aquatic and semiaquatic species, including turtles and ray-finned fish. The authors named this fossil collection the Zhenghe Fauna. This diverse array of inhabitants and environment suggests that it was the site of emerging Jurassic vertebrate fauna around the time when Fujianvenator was there. This find and timing fills in an important gap in our understanding of ecosystems in Late Jurassic Northeast Asia and the team plans to continue to explore Zhenghe and other nearby areas.

The post Leggy dinosaur species could be the latest feathery clue to bird evolution appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

The mechanics of how athletes like New York Giants quarterback Daniel Jones’ are able to throw a perfect spiral or how wide receiver Darius Slayton may extend his elbow to reach for the catch may have ancient roots. These skills may have first evolved as a natural braking system for our primate ancestors who simply needed a safe way to get out of trees. 

[Related: Chilly climates may have forged stronger social bonds in some primates.]

In a study published September 6 in the journal Royal Society Open Science, a team from Dartmouth found that apes and early human ancestors likely evolved free-moving shoulders and flexible elbows as a way to slow their descent from trees while gravity pulled down on their bodies. Versatile appendages that could throw spears for hunting and defense, climb trees, and gather food were essential for survival—especially as early humans left forests for grassy savannas.

“There’s a lot we still don’t understand about the origin of apes,” study co-author and Dartmouth University paleoanthropologist Jeremy DeSilva tells PopSci. “There was a common ancestor to monkeys and apes that lived about 25 to 30 million years ago and then there was a divergence and now we have these two different kinds of primates. But why the convergence?”

One of the possibilities is different ecological, physical, and behavioral niches related to primate size. The first apes evolved about 20 million years ago and are bigger than other early primates. Getting out of a tree presented a new set of challenges for these bigger primates, since typically the bigger the animal, the greater the risk of injury from a fall. Natural selection would have eventually favored anatomies that allowed early apes to safely descend from the trees. 

In the study, the team used sports-analysis and statistical software to compare videos and still-frames of chimpanzees and small monkeys called mangabeys climbing in the wild. They saw that mangabeys and chimps climbed up the trees similarly, with their shoulders and elbows mostly bent close to the body. 

However, when it was time to climb down, chimpanzees extended their arms above their heads to hold onto branches, similar to how a person going down a ladder, as their weight pulls them down. This process called “downcliming” appears to be significant in the evolution of apes and early humans.

“Our study broaches the idea of downclimbing as an undervalued, yet incredibly important factor in the diverging anatomical differences between monkeys and apes that would eventually manifest in humans,” study co-author and Dartmouth graduate student Luke Fannin said in a statement. 

[Related: How to hike downhill safely and comfortably.]

These flexible shoulders and elbows passed on from ancestral apes would have allowed early humans such as Australopithecus to climb into trees at night for safety and then come down in the daylight unscathed. Once Homo erectus could use fire to protect itself at night, the human form took on the broader shoulders capable of a 90-degree twist that worked with free moving shoulders and elbows to make human ancestors excellent shots with a spear for hunting.

“The idea that downclimbing could be such a strong evolutionary force as to change the nature of how our bones and range of motion evolved was very fascinating,” study co-author Mary Joy tells PopSci. “Not a lot of the field really thinks about downclimbing as its own motion with implications on natural selection.” Joy brought her experience as a trail runner and athlete to the study to bring in a different perspective to looking at biological sciences and evolution. 

The team also used skeletal collections from Harvard University to study the anatomical structure of chimpanzee arm alongside remains in The Ohio State University’s collections to study  mangabey arms. Chimpanzees are more like humans than mangabeys and have a shallow ball-and-socket shoulder that allows for a greater range of movement. Chimps can also fully extend their arms due to a reduced length of bone located just behind the elbow called the olecranon process.

Mangabeys and other monkeys are built more like four-legged animals like cats and dogs, with deep pear-shaped shoulder sockets and elbows that have a protruding olecranon process, which makes the joint look like the letter L. These joints are more stable, but they have a more limited range of movement and flexibility.

The analysis showed that the angle of a chimp’s shoulders was 14 degrees greater during their descent than when scaling a tree. The arm also extended outward at the elbow 34 degrees more when climbing down a tree than climbing up. The angles at which the mangabeys positioned their shoulders and elbows were only about four degrees or less when ascending a tree versus downclimbing.

“If cats could talk, they would tell you that climbing down is trickier than climbing up and many human rock climbers would agree. But the question is why is it so hard,” study co-author and 

anthropologist and evolutionary biologist Nathaniel Dominy said in a statement. “The reason is that you’re not only resisting the pull of gravity, but you also have to decelerate. 

[Related: Lucy, our ancient human ancestor, was super buff.]

According to DeSilva, the question of “how did we not see this before” in regards to downclimbing was one of the most surprising parts of the study. The fresh eyes of both Joy and graduate student Fannin were crucial in uncovering one of evolution’s hidden wonders. 

“Our evolutionary ancestry is this wonderful example of how evolution just sort of tinkers and tweaks pre-existing forms,” says DeSilva. “Our bodies are bodies that have been just tweaked and modified through natural selection over millions of years, to give us the bodies we have now, but there are all these wonderful echoes of our ancestry in our bodies today.”

The post Our tree-climbing ancestors evolved our abilities to throw far and reach high appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Finding lasting love can be really difficult. We’ve all heard the annoying adages like “there’s plenty of fish in the sea,” not to mention the old “opposites attract” chestnut. However, many people tend to end up being quite similar to their partners, according to the results of a study published August 31 in the journal Nature Human Behaviour.

[Related: Social relationships are important to the health of aging adults.]

The new research included numerous studies dating back more than a century. The team examined 130 traits from millions of couples, ranging from political leanings to age of first sexual intercourse to substance use habits. For between 82 and 89 percent of traits analyzed, partners were more likely than not to be similar. In only one part of the analysis, and for only three percent of studied traits, did individuals tend to be coupled with someone who is demonstrates an opposing trait.

In addition to shedding light on some of those unseen forces that may shape human relationships, this research could have some important implications for the field of genetic research.

“A lot of models in genetics assume that human mating is random. This study shows this assumption is probably wrong,” study co-author and University of Colorado at Boulder psychologist and neuroscientists Matt Keller, said in a statement. Keller noted that a tendency called assortative mating—when individuals with similar traits couple up—can actually skew findings of genetic studies.

To find their results, the team conducted both a meta-analysis of previous research and their own original data analysis. In the meta-analysis, they examined 22 traits across 199 studies of millions of male-female co-parents, engaged pairs, married pairs, or cohabitating pairs. The oldest study in this analysis was conducted back in 1903. They also used a dataset called the UK Biobank to analyze 133 traits across almost 80,000 opposite-sex pairs in the United Kingdom.

Same sex couples were not included in the research because the patterns in these types of partnerships may differ significantly. The authors are now pursuing those relationships in a separate study.

[Related: These fuzzy burrowers don’t need oxytocin to fall in love.]

Traits such as political and religious attitudes, level of education, and certain measures of IQ showed particularly high correlations. For example, on a scale of 0 meaning no correlation and 1 meaning couples always share a trait, the correlation for political values was .58. Traits surrounding substance use also showed high correlations, with heavy drinkers, smokers, and teetotalers tending to strongly pair with those who share similar traits. Traits like height and weight, medical conditions, and personality showed much lower but still positive correlations. For example, the correlation for neuroticism was .11.

Interestingly, some traits, such as extroversion, did not have much of a correlation.

“People have all these theories that extroverts like introverts or extroverts like other extroverts, but the fact of the matter is that it’s about like flipping a coin: Extroverts are similarly likely to end up with extroverts as with introverts,” study co-author and University of Colorado at Boulder PhD student Tanya Horwitz said in a statement. 

The meta-analysis found “no compelling evidence” that on any trait that opposites attract. However, in the sample from the UK Biobank, the team did find a handful of traits in which there seemed to be a small negative correlation, including hearing difficulty, tendency to worry, and whether someone is more of a morning person or night person (called chronotype). Additional studies will be needed to understand those findings, according to the team. 

Some of the less-frequently studied traits including number of sexual partners and whether an individual had been breastfed as a child also showed some correlation.

“These findings suggest that even in situations where we feel like we have a choice about our relationships, there may be mechanisms happening behind the scenes of which we aren’t fully aware,” said Horwitz.

According to the authors, couples could share traits for a variety of reasons, including growing up in a similar area. Some people are simply attracted to those who are similar based on the traits studied, and some couples grow more similar the longer they stay in the relationship. 

These pairings could lead to some downstream genetic consequences. For example, if short people are more likely to produce offspring with a similar height and vice versa, there could be more people at the height extremes in the next generation. This same thing apply for medical, psychiatric, and other traits according to Horowitz. 

Some of the social implications include those with similar educational backgrounds continuing to pair up, which could widen socioeconomic divides.

The team cautions that the correlations found were fairly modest and should not be overstated or misused to promote an agenda. Assortative mating has historically been dangerously co-opted by the eugenics movement, which gained traction during the early 20th century.

The post Couples often share more common traits than we might think appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A newly discovered three-eyed relative is disappointingly unrelated to the eerie three-eyed ravens of Game of Thrones. But this Cambrian-era beast is a relative of today’s insects and boasts some fearsome limbs. The unique fossilized animal was described in a study published August 28 in the journal Current Biology. 

[Related: This ancient ‘mothership’ used probing ‘fingers’ to scrape the ocean floor for prey.]

The animal, scientific name Kylinxia, was found in 520 million year old rocks in a fossil deposit called the Cambrian Chengjiang biota near the town of Chengjiang in southern China. More than 250 species of exceptionally well-preserved fossil organisms have already been described from this location, which gives scientists a glimpse of what was going on in the world’s oceans as they developed. 

Importantly, Kylinxia is filling in some evolutionary gaps in our understanding of the evolution of animals known as arthropods. This phylum of animals includes insects, crabs, shrimp, scorpions, spiders, and centipedes among others. Arthropods have an exoskeleton made of a tough material called chitin that is mineralized with calcium carbonate, as well as a body divided into segments and paired jointed appendages. They are considered some of Earth’s most successful species and over 85 percent of all known animal species are classified as arthropods.

Kylinxia was about the size of a large shrimp, had a pair of limbs that it likely used to catch prey, and a signature trio of eyes on its head. 

“Most of our theories on how the head of arthropods evolved were based on these early-branching species having fewer segments than living species,” Greg Edgecombe, a co-author of the study and arthropod evolution expert at London’s Natural History Museum, said in a statement. “Discovering two previously undetected pairs of legs in Kylinxia suggests that living arthropods inherited a six-segmented head from an ancestor at least 518 million years ago.”

After its initial discovery, Kylinxia was imaged using a CT scanner. The scan revealed that more soft parts of the animals’ anatomy were also buried in the rock. While there are plenty of species of arthropods preserved in the fossil record, most fossils only preserve the hard skeletons. 

[Related: Newly discovered fossils give a whole new meaning to jumbo shrimp.]

“The preservation of the fossil animal is amazing,” study co-author and University of Leicester PhD student Robert O’Flynn said in a statement. “After CT-scanning we can digitally turn it around and literally stare into the face of something that was alive over 500 million years ago. As we spun the animal around, we could see that its head possesses six segments, just as in many living arthropods.”

This new specimen was nearly complete, which enabled the team to identify the six segments that made up its body: the head, a second segment with its grasping limbs, and the other four segments which have a pair of jointed limbs.

“Robert and I were examining the micro-CT data as part of his doctoral thesis in the hope of refining and correcting previous interpretation of head structures in this genus, Kylinxia,” study co-author and Yunnan Key Laboratory for Palaeobiology paleobiologist Yu Liu said in a statement. “Amazingly, we found that its head is composed of six segments, as in, e.g., insects.”

The post A three-eyed organism roamed the seas half a billion years ago appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

If the mighty Ice Age sabertooth tiger called out in a forest, and no one was around to hear it, did it even make a sound? A team of researchers from North Carolina State University set out to answer that philosophical question by investigating if sabertooth cats had a throaty purr or a mighty roar. They found that tiny bones in the tiger’s throat might present a more  nuanced answer. Their findings were published August 21 in the Journal of Morphology. 

[Related: Life in Los Angeles was brutal for saber-toothed cats.]

Present-day cats belong to two subfamilies who make different vocalizations. The pantherine or “big cats” include lions, jaguars, and tigers who typically roar. Felinae or “little cats” includes domestic cats, ocelots, lynxes, and cougars who purr. For cats that roar, the structures that surround their larynx (or voice box) generally aren’t stiff enough to make the purring sound.

“Evolutionarily speaking, sabertooths split off the cat family tree before these other modern groups did,” study co-author and NC state biologist Adam Hartstone-Rose said in a statement. “This means that lions are more closely related to housecats than either are to sabertooths.

Vocalization is driven by the larynx and soft tissue in the throat, not bones. However anatomists noticed that the bones responsible for anchoring those tissues in place called the hyoid bones differed in both number and size between purring and roaring cats. 

“While humans have only one hyoid bone, purring cats have nine bones linked together in a chain and roaring cats have seven,” co-author and NC State Ph.D. student Ashley Deutsch said in a statement. “The missing bones are located toward the top of the hyoid structure near where it connects to the skull.”

According to the team, sabertooth tigers only have seven bones in their hyoid structure, but the shape and size look eerily similar to some purring cats’ bones. If vocalization is related to the number of bones in the hyoid structure, then the sabertooths roared. However, if it is about shape, they may have purred. 

“You can argue that since the sabertooths only have seven bones they roared, but that’s not the whole story,” said Hartstone-Rose. “The anatomy is weird. They’re missing extra bones that purring cats have, but the shape and size of the hyoid bones are distinct. Some of them are shaped more like those of purring cats, but much bigger. 

[Related: Orangutans can make two sounds at the same time.]

According to the team, if the missing bones (the epihyoid bones) were the key to different vocalizations, then the bones that are most closely connected to them should appear different between purrers and roarers. Those bones actually looked very similar in shape in the purring variety of cats.

The team saw more shape variation in the bones that are closer to the vocal apparatus, like the the thyrohyoid and basihyoid bones. Having these key hyoid bones shaped like those belonging to purring cats may indicate that they purred like a kitten instead of roaring like a lion, but it is still a bit of a prehistoric mystery. 

“It is perhaps most likely that the size of the hyoids plays a role in the pitch of vocalization,” said Deutsch. “Although Smilodon wasn’t quite as big as the largest modern cats, its hyoid bones are substantially larger than those of any of their living relatives, so potentially they had even deeper vocalizations than the largest tigers and lions.”

The post Mighty sabertooth tigers may have purred like kittens appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Ocean temperatures are surging worldwide largely due to human-made climate change and natural El Niño driven patterns. The rise is wreaking havoc on the planet’s coral reefs, however a study published August 22 in the journal Nature Communications found that the coral reefs in one part of the Pacific Ocean can likely adjust to some rises in temperature. This adaptation has the potential to reduce future coral bleaching as the climate continues to change. 

[Related: The heroic effort to save Florida’s coral reef from a historic heatwave.]

“We know that coral reefs can increase their overall thermal tolerance over time by acclimatization, genetic adaptation or shifts in community structure, however we know very little about the rates at which this is occurring,” study co-author and Newcastle University coral reef ecologist James Guest said in a statement. 

The rate at which coral reefs can naturally increase thermal tolerance, and if it can match pace with warming, is largely unknown. So the team started their work by investigating historic mass bleaching events that have occurred since the late 1980s in a remote Pacific coral reef system. 

They focused on a reef system Palau, an island country in the western Pacific Ocean, and found that increases in the heat tolerance of reefs is possible. Reefs here are known as a bevy of biodiversity and provide a barrier from storms. The team used decades of data to create models of multiple future coral bleaching trajectories for Palauan reefs. Each model had a different simulated rate of thermal tolerance enhancement. The team found that if coral heat tolerance continues to rise throughout this century at the most-likely high rate, significant reductions in bleaching impacts are actually possible.

The results affirm the general scientific consensus that the severity of future coral bleaching will depend on reducing carbon emissions. For example, if the commitments of the 2015 Paris Agreement to limit future warming to 2.7 degrees Fahrenheit, high-frequency bleaching can be fully mitigated at some reefs under low-to-middle emissions scenarios. These bleaching impacts are unavoidable under high emissions scenarios where society continues to rely on fossil fuels.  

Coral communities will need to persist under constant climate change and will likely need to endure progressively more intense and frequent marine heatwaves. The team believes that the observed increase in tolerance suggests that some natural mechanisms, such as genetic adaptation or acclimatization of corals or their symbiotic microalgae, may contribute to the increased heat tolerance. 

[Related: To save coral reefs, color the larvae.]

While this is some positive news for Pacific coral, the resilience comes at a high cost. Adaptations like these can reduce reef diversity and growth, and without cutting future greenhouse gas, the Pacific’s reefs won’t be able to provide the habitat resources and protection from waves that residents depend on.

“Our study indicates the presence of an ecological resilience to climate change, yet also highlights the need to fulfill Paris Agreement commitments to effectively preserve coral reefs,” study co-author and Newcastle University coral reef ecologist Liam Lachs said in a statement. “We quantified a natural increase in coral thermal tolerance over decadal time scales which can be directly compared to the rate of ocean warming. While our work offers a glimmer of hope, it also emphasizes the need for continued action on reducing carbon emissions to mitigate climate change and secure a future for these vital ecosystems.”

The post Some Pacific coral reefs can keep pace with a warming ocean appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

As if the thought of a flying pterosaur with a 6.5 foot wingspan dominating Earth’s skies wasn’t terrifying enough, paleontologists have now found an even older pterosaur ancestor with some prominent claws. The latest find might not have its signature wings just yet, but boasts a beak and sharp claws. The roughly 230-million-year-old lagerpetid unearthed in Brazil is described in a study published on August 16 in the journal Nature. 

[Related: This pterosaur ancestor was a tiny, flightless dog-like dinosaur.]

Pterosaurs and dinosaurs both evolved about 235 million years ago in the Middle to early Late Triassic (about 235 million years ago). Dinosaurs went on to dominate the land during the Jurassic Period (201.3 to 145 million years ago) and the winged pterosaurs took over the skies during the Cretaceous Period (145.5 to 66 million years ago). 

While some new discoveries including finding Scleromochlus taylori in 2022 have filled in evolutionary gaps and helped paleontologists learn more about these winged critters, the fossil record from this time still remains relatively scarce. Lagerpetids like this newly discovered clawed specimen are the closest known non-flying group to pterosaurs.

In this new study, a team describes the well-preserved partial skeleton of a lagerpetid that they named Venetoraptor gassenae. The team estimates that V. gassenae would have been about 27.5 inches tall and about 39 inches long. The bone features indicate that this particular animal was an adult when it died. It also had feather-like fur on its body and a long tail.

“Because cranial remains are so scarce for lagerpetids, this is the first reliable look into the face of these enigmatic reptiles,” study co-author and paleontologist Brazil’s Universidade Federal de Santa Maria Rodrigo Müller told Gizmodo. “The unusual skeleton of Venetoraptor gassenae reveals a completely new morphotype of pterosaur precursors.”

V. gassenae’s more notable features include a raptorial-like beak and large hands with claws that resemble a curved sword. The team believes that the Veneraprot was highly specialized to its ecological niche. Its claws may have helped it climb or handle its prey, and V. gassenae also has an elongated fourth digit on its fossilized right hand. According to Müller, this has not been seen in other lagerpetids, which hints that V. gassenae is especially closely related to pterosaurs.

[Related: Dinosaur Cove reveals a petite pterosaur species.]

“This elongated fourth digit supports the wings in pterosaurs, so V. gassenae may represent the transition of lagerpetids towards pterosaurs,” Müller told LiveScience.

It’s unclear what role that its long beak played. Beaks obviously can help animals eat, but they can also have many functions beyond feeding, including sexual displays, vocalization, and regulating body temperature. 

By studying this fossil alongside the remains from 18 dinosaur and 10 pterosaur species from this time period, the team believes that lagerpetids were as morphologically diverse as Triassic pterosaurs and even more morphologically diverse than Triassic dinosaurs. It shows that this level of biodiversity was already starting to flourish in the precursors of both dinosaurs and pterosaurs and was not something that only emerged after both groups originated. 

The post This flightless pterosaur ancestor had enviable claws and a raptor-like beak appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

On August 15, a schooner set sail from Plymouth on the southern coast of England to recreate the South America-bound voyage taken by biologist Charles Darwin almost 200 years ago. The Dutch tall ship Oosterschelde began its two year mission as a floating laboratory, where about 200 conservationists and naturalists will gather along the way to take part in a project called Darwin200.

[Related: Let’s talk about Charles Darwin’s sexy theory of selection.]

In 1831, the HMS Beagle set sail from Plymouth with a then 22-year-old Charles Darwin aboard. The five-year journey was primarily intended to explore the coastline of South America and chart its harbors, with Darwin tasked to make scientific observations. He explored Brazil, Argentina, Chile, and the remote areas of the Galápagos Islands. Over the course of the journey that Darwin said was “by far the most important event in my life,” he brought back specimens of more than 1,500 different species and this work influenced his book On the Origin of Species and the theory of evolution.

The Oosterschelde is expected to make the 40,000 nautical mile expedition and hopes to anchor in 32 ports, including all the major ports visited by the Beagle. It expected to make its first landing in the Canary Islands and then cross the Atlantic Ocean to Brazil. It will then follow along South America’s eastern coast, up the west coast, and out to the Galápagos. It will then sail to Australia and New Zealand, before stopping in South Africa, and returning to England.

“I always think it is very much worth reminding ourselves on a daily basis that humans and the rest of the living world share a common origin,” Sarah Darwin, a botanist and the great-great-granddaughter of Charles Darwin told the Associated Press. “Darwin was saying that 160 years ago, that we were related with all other nature. We’re not above it, we are part of nature.” 

The Darwin200 project has been in the works for at least a decade and aims to empower a new generation of exceptional environmental leaders through training some of the world’s top young conservationists ranging from 18 to 25 years-old. 200 young people were selected based on their accomplishments aimed at making the world a better place and will join the voyage at different stages. 

“This is about hope, it’s about [the] future and it’s about changing the world,” leader Stewart McPherson told the AP. 

[Related: Letters From Charles Darwin.]

Today’s naturalists are studying a world a bit different than Darwin. The planet’s birds, reptiles, mammals, fish, and amphibians have already shown population declines of around 68 percent since the 1970s and 10 percent of terrestrial biodiversity is set to decrease by 2050 if new policies are not immediately put in place. In December 2022, 200 countries’ delegates  at the United Nations Biodiversity Conference (COP 15) reached the 30 by 30 deal, vowing to protect 30 percent of the Earth’s wild land and oceans by 2030, thus representing the most significant effort ever to protect the world’s dwindling biodiversity. The deal also provides funding in an effort to save and preserve biodiversity in lower-income countries. Currently, only 17 percent of terrestrial and 10 percent of marine areas are protected through legislation.

Still, more work is needed as some scientists believe current estimates of biodiversity loss are even higher than scientists first expected. One of the goals of Darwin200 is to develop projects to save the species it is studying along the way before it’s too late.

“We all know we’re in the midst of the sixth great extinction with a lot of doom and gloom about the problems facing the environment, climate change and loss of biodiversity,” Famed primatologist and Darwin200 supporter Jane Goodall told Reuters. “This voyage will give many people an opportunity to see there is still time to make change.”

The post Mission to recreate Darwin’s scientific Beagle voyage sets sail appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Over 23 million years ago, an ancient relative of modern seals called Potamotherium valletoni was possibly one of the first pinnipeds to use their whiskers to forage for food and explore their watery world. The findings were published August 17 in the journal Communications Biology and provide more insight into how ancient seals transition from a life lived on land into one mostly underwater. 

[Related: Baby seals are born with a great sense of rhythm.]

The relatives of present day pinnipeds primarily lived on land and in freshwater environments, unlike our recognizable harbor seals which spend most of their time under the waves in saltwater. These early seals had legs for walking instead of flippers, a long tail, and were much longer, and looked a bit like present-day otters. 

“Pinnipeds (seals, sea lions and walruses) diversified tremendously since their ancestors entered the seas,” study co-author Alexandra van der Geer, a vertebrate paleontologist at the Naturalis Biodiversity Center in the Netherlands tells PopSci. “All living pinnipeds are very distantly related to Potamotherium, so one could say that in a way all living pinnipeds are equally closely related to Potamotherium. That is why Potamotherium is called a stem (or basal) pinniped.”

Some early species used their forelimbs to explore their surroundings, and prior to this study, scientists were unsure when seals and their relatives began using their whiskers to forage. Whiskers are thick wiry hairs with tons of nerve endings at their base and they’re very sensitive to movement. They can be used to help detect vibrations in the water, making it easier to find fish. 

Van der Geer and colleagues from institutions in Italy, Greece, and Sweden were inspired to look into this area of neurobiology by a visit to Chicago’s Field Museum. There, they studied the museum’s collection of special skull models called endocasts.  “An endocast is the infilling of the inside of the skull, so it fills up the space of the (former) brain. The brain is soft tissue and does not fossilize, but decomposes and disappears after death,” explains van der Geer.

In the study, they used these endocasts to investigate the evolution of whisker-foraging behaviors. They compared the brain structures of Potamotherium with six extinct and 31 living carnivorous mammals, including bears, mustelids, and seal relatives. The team compared the size and structure of a brain region called the coronal gyrus. Some earlier studies suggest that this region is involved in processing signals from seal whiskers. 

[Related: Seals snooze during 20-minute ‘sleeping dives’ to avoid predators.]

They found that Potamotherium had a larger coronal gyrus than both ancient and living land-based mammals that use their forelimbs to forage, such as the Asian small-clawed otter. However, it had a similar sized coronal gyrus to other ancient seal relatives and semiaquatic mammals that use whiskers to explore, including the Eurasian otter. This shows that Potamotherium may have used a combination of forelimbs and whiskers to forage.  

The team was surprised by the convergent evolution they saw in their study. “Not just seals but also some otters, civets and other carnivore mammals that are unrelated to seals, yet use their whiskers for foraging their prey underwater in the same way as seals, developed the same part of the brain,” van der Geer says. 

Additionally, they were surprised to see that coronal gyrus looks the same species with the same behavior, independent of their family ties. The team believes that whisker-based foraging may have already been present in seal relatives before they transitioned to their fully aquatic lifestyles of today. Using whiskers may have helped the Miocene-era creatures adapt to finding food underwater.

The study also shows the value of studying brain endocasts to look into the past. “By looking at the details of the brain endocast one can infer behavior and function in fossil species,” says van der Geer.

The post Hungry seals may have begun following their whiskers 23 million years ago appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

This article is excerpted from Roberto Battiston’s book “First Dawn: From the Big Bang to Our Future in Space.” This article originally published on MIT Press Reader.

By the time we realized that there was an extrasolar intruder, ‘Oumuamua, named after the Hawaiian word for “scout,” had already passed its closest point to the Sun and was leaving, as fast and stealthily as it had arrived. We are talking about the first sighting, in 2017, of an asteroid from another area of the galaxy, a messenger from distant worlds. What do we know about this dark, probably cigar-shaped shard, which visited our solar system with a trajectory and velocity that allowed it to leave so quickly?

Very little. We know that it was not made of ice, so it must be of the rocky type. It did not ignite like a comet as it approached the Sun. We know that it does not emit electromagnetic radiation. The most powerful radio telescopes have found no trace of it. Its orbit is gravitational, determined by the attraction of the Sun; a small, non-inertial component can be explained by the effect of the pressure of the radiation in our star’s vicinity. We know that its speed, before entering the solar system, was compatible with the characteristic speeds of celestial bodies in the region of the Milky Way, of which our solar system is part. This allows us to exclude the idea that it comes from one of the dozen stars closest to us, as its velocity would have been too high. However, we have identified four more distant stars near which it could have passed in the last million years, with a velocity low enough that it could have originated in one of these star systems.

So, we don’t know exactly where it comes from, if it has already been in our solar system, how many other systems it has visited, or its composition. According to one hypothesis, it could be a fragment of an exoplanet destroyed by tidal effects. In this case it would be an object much rarer than main belt asteroids or objects from the Oort cloud, which formed directly from the original nebula. What is certain is that, on timescales of the order of millions or tens of millions of years, fragments like ‘Oumuamua can bring different star systems into contact. One estimate even predicts that 10,000 extrasolar asteroids cross Neptune’s orbit on a daily basis.

On timescales of the order of millions or tens of millions of years, fragments like ‘Oumuamua can bring different star systems into contact.

It would be interesting to be able to explore one to see what it was made of. This type of asteroid would seem to be the kind of vector suitable for transporting life, in hibernating form, from one part of the galaxy to another. While a space mission of this kind would be difficult because of the speed at which these fragments are moving, it wouldn’t be impossible, considering that in the future our observational capacity will improve considerably, allowing us to identify these bodies sooner than we were able to identify ‘Oumuamua. Another idea has to do with the possibility that some of these extrasolar objects have become trapped in our solar system after having lost some of their energy in a close encounter with Jupiter; a few candidates have already been identified. This approach would make an exploratory mission much easier to accomplish.

However, even the planets in our own solar system are in communication and exchanging material at a fairly high rate. Not everyone knows that we have about 10 rock samples from Mars here on Earth, even though there has not yet been a mission that brought back material from that planet. The meteorite bombardment on Mars results in fragments that, given its thin atmosphere, can be projected into space. Some of them can reach the Earth, penetrate our atmosphere, and fall like normal meteorites. By comparing the isotopic composition of various meteorites with those measured on Mars during NASA’s robotic missions to the planet, we are able to identify and distinguish Martian meteorites from all the others.

Finally, we should remember that it takes the solar system about 220 million years to revolve around the center of the galaxy. Since it formed 4.5 billion years ago, it has made the full circuit about 20 times. This means that, in the timescale in which life emerged on Earth, the newborn solar system made at least three complete circuits, coming into contact with fragments from distant star systems.

In 2019 I participated in a Breakthrough Discuss conference in Berkeley on “Migration of Life in the Universe.” I was puzzled by the conference theme: We know almost nothing about life in the universe, I thought, so how we could talk about migration of life? But recalling the observation of ‘Oumuamua, I did participate and I am glad I did. I was surprised by the scientific quality of the talks and by the extreme fascination of the topic. Life probably doesn’t need massive, rocky starships to move from one planetary system to another. Considering the minuscule size of bacteria, the smallest living organisms we know, or even viruses, which can live and reproduce inside bacteria, we can also imagine other mechanisms suitable for this kind of transport.

Microscopic ice crystals and dust, for example, containing bacteria and spores capable of withstanding the conditions in space, can spread into space from areas of a planet’s upper atmosphere. When the dimensions become microscopic, the relationship between gravitational force, which is dependent on mass, and the thrust due to stellar radiation, which is dependent on surface area, tips the balance in favor of the latter. It is as if a planet were leaving a trail of perfume behind it. Planetary dust containing hibernating life can be pushed by radiation until it reaches high velocities and moves beyond a given star system, spreading to other systems or nebulae, where it can find suitable conditions to reproduce and evolve. We are used to thinking of space as vast and mostly empty, completely unsuitable for life. Perhaps we should change our minds. Space is less empty than we might think. In reality, the different parts of the galaxy communicate by exchanging material on timescales comparable to those of the appearance of life on our planet.

We know of various living species that can endure extremely hostile conditions such as those in space: a nearly perfect vacuum, extreme temperatures, and ionizing radiation.

But how possible is it for life to survive in space? Well, even here, nature surprises us. In fact, we know of various living species that can endure extremely hostile conditions such as those in space: a nearly perfect vacuum, extreme temperatures, and ionizing radiation. Different kinds of lichens, bacteria, and spores are able to survive, losing all of their water and entering into a condition of total inactivity — which can last for extremely long periods — from which they can emerge, once they find themselves in a humid atmosphere again. Tests of this kind have been done on the International Space Station and in various laboratories. Even plankton, made of more complex organisms, shows a capacity to resist these prohibitive conditions.

A truly extraordinary case is that of the tardigrades. These very common micro-animals are about a half a millimeter long and live in water. They have eight legs, a mouth and a digestive system, as well as a simple nerve and brain structure. They are also able to sexually reproduce. They exist in nature in thousands of different versions and have a metabolism with unique characteristics. In order to withstand prolonged drought conditions, their bodies can achieve complete dehydration, losing around 90 percent of their water and curling up into a tiny, barrel-shaped structure. In other words, it’s as if they freeze-dry themselves. Once this process is complete, their metabolism becomes 10,000 times slower. The most amazing thing is that they can stay in this state for decades, only to wake up again within 20 or 30 minutes once exposed to moisture. But there’s more. When in a dehydrated state, they can withstand the vacuum of space as well as pressures higher than normal atmospheric pressures, temperatures near absolute zero or temperatures up to 150°C. Their radiation tolerance threshold is hundreds of times higher than what would be deadly for humans. The secret of their ability to harden is due to a sugar, trehalose, which is also widely used in the food industry. When dried, this sugar replaces the water molecules in the cells, leaving the animal in a kind of vitrified state.

In addition, the tardigrade’s DNA is protected by a protein that reduces radiation damage. Is this information enough to make us assume that these micro-animals come from space? I would say no. Their unusual metabolism is more likely the result of evolutionary adaptation that happened on our planet. In fact, tardigrades are among the very few living beings that have emerged unscathed from all five extinction events that have occurred on Earth. That is why they are the best candidates for a long journey into space aboard a meteorite or a comet. Recently, tardigrades have achieved a bit of media notoriety resulting from the Beresheet mission, a private probe launched by Israel, that crashed on the Moon in early April of 2019. The probe was carrying a colony of these micro-animals, in their dehydrated state. Given their microscopic size, it is likely that they survived the crash and will remain inactive for a long time to come, ready to be reawakened from their hibernation. By replacing the Israeli probe with an asteroid, we have a textbook example of how life might have arrived on Earth.

Or how life could have migrated from Earth to other planets in our galaxy.

By replacing the Israeli probe with an asteroid, we have a textbook example of how life might have arrived on Earth.

So, the problem of the origin of life remains open, even if, step by step, we are making progress toward a solution. In the last decade, increasingly powerful calculation instruments have allowed us to reproduce, starting from the first principles of quantum mechanics, the formation of increasingly large and complex molecular systems, now made up of thousands of atoms. The field of computational biology is growing at a formidable rate; it is now only a matter of computing power.

At the same time we have dramatically developed our ability to decode and manipulate DNA, up to the creation of the first simplified genomic structures, derived from living organisms and able to reproduce. We are now talking about synthetic life, built around human-designed DNA, a field with huge development prospects.

Therefore, it is likely that the creation of the complex molecular structures needed for life or the confirmation of the existence of islands of genomic stability in the evolution of viral and bacterial species are objectives that, in future, will be within our reach. At that point, we will have another tool for understanding how life on Earth developed. Who knows? Perhaps we will discover that aliens are particular biological life forms that have lived with us since the beginning of time; and we were looking for them on Mars or below the icy surface of Jupiter and Saturn’s moons!

Roberto Battiston is a physicist who specializes in the field of experimental fundamental and elementary particle physics, both with particle accelerators and in space. He is the author of several books, including “First Dawn,” from which this article is excerpted.

The post How might life migrate through the universe? appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A 300,000 year-old fossilized skull discovered in China is proving to be an evolutionary puzzle. The specimen dating back to the late middle Pleistocene doesn’t look like other skulls that have been found from this time period, and could possibly point to a previously unknown human species. The findings were published late last month in the Journal of Human Evolution.

[Related: Leftovers of a 2,000-year-old curry discovered on stone cooking tools.]

A team of scientists from institutions in Spain, the United Kingdom, and China found the lower jaw–or mandible–and 15 other separate specimens in eastern China’s Hualongdong region in 2015. The mandible in question is named HLD 6 and dates back to an important period in hominin evolution, just before some of the traits that are still seen in modern humans began to evolve in East Asia. 

The study noted that HLD 6 was “unexpected” since it doesn’t currently fit into any known taxonomic groups. The skull has similar facial features to those of early modern humans. The skull could potentially belong to a direct human ancestor called Homo erectus sometime between 550,000 and 750,000 years ago. 

However, it also shares some of the characteristics of the Denisovans, who belong on a different branch on the human family tree than Homo Erectus. HLD 6 does not appear to have a chin, just like previously discovered Denisovan specimens. Denisovans are now extinct and split from Neanderthals about 400,000 years ago.

Given that the specimen has a mixture of Homo erectus and Denisovan characteristics, they believe this was potentially a hybrid of modern human and ancient hominid. The team notes that this combination of facial features hasn’t been observed in East Asia hominids, which suggests that some of the traits found in modern humans began to appear as far back as 300,000 years ago.

[Related: A javelin-like stick shows early humans may have been keen woodworkers.]

They believe that the fossils belonged to a 12- to 13-year-old child. The team did not have an adult skull belonging to this same species to compare it with, but they used Middle and Late Pleistocene hominin skulls of similar and adult age. They noticed that the shape patterns remained the same regardless of age, which they say supports the theory that this could be a different human species. 

The history of the human family tree is constantly changing, as scientists develop better techniques for finding and analyzing specimens. A study published in June proposed that humans entered the forests of Asia about 400,000 years earlier than they previously believed. Humans and Neanderthals also could have been interbreeding earlier and in three separate waves that eventually led to the extinction of Neanderthals. 
If this new theory proves to be correct, a new “pre-sapiens specimen” branch could be added to this complex family tree and bring more insight into human evolution.

The post Mysterious skull points to a possible new branch on human family tree appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

What goes into the body, must ultimately come out.  The same goes for the parasites living within a host. The parasite-host relationship is also pretty old, and some newly found fossilized feces show the ancient parasites infected an aquatic predator more than 200 million years ago. The findings are published August 9 in the open-access journal PLOS ONE.

[Related: ‘Brainwashing’ parasites inherit a strange genetic gap.]

Despite being a common and important player in the food web due to their role in regulating overpopulation within the ecosystem, ancient parasites are difficult to study in the fossil record. They typically inhabit their host’s soft tissues, which are not usually preserved in fossils like tougher parts like bones. However, traces of parasites can sometimes be identified in fossilized feces which are called coprolites. 

“Coprolite is a significant paleontological treasure trove, containing several undiscovered fossils and expanding our understanding of ancient ecosystems and food chains,” the authors wrote in a statement.

In this study, the team describes evidence found in coprolite dating back to the Late Triassic from Thailand’s Huai Hin Lat Formation, which is over 200 million years old. The coprolite is shaped like a cylinder and more than 2.7 inches long. The team believes that it was likely produced by some species of a crocodile-like predator called a phytosaur based on the shape of the fossilized poop and the remains of phytosaurs have been found in the area for decades. 

Within the thin sections of coprolite, the team found six small, round, organic structures roughly between only 50 to 150 micrometers long. One of these microscopic beauties is an oval-shaped structure with a thick shell which the team identified as the egg of a parasitic nematode worm called Ascaridida. The other five structures possibly represent additional worm eggs or protozoan cysts. 

“The discovery of at least six parasites with at least five different morphotypes in a single coprolite suggests that multi-parasite infection was common had already diversified by the late

Triassic,” the authors wrote in the study. 

It is believed to be the first record of parasites in a terrestrial vertebrate host in Asia from the Late Triassic period, when the Earth was warmer and more humid than it is today. It also offers a glimpse into an ancient animal who was infected by multiple species of parasite as it went about its life. 

[Related: What prehistoric poop reveals about extinct giant animals.]

“The presence of the Ascaridida eggs and the evidence for multi-infection found in the coprolite can presumably be explained by the predatory habits of the host, which would have been parasitized by feeding on parasitized fishes, amphibians, or other reptiles,” they wrote.

This finding also adds to the few known examples of nematode eggs preserved within the fossilized poop in prehistoric animals and will add more understanding to how parasites were distributed on Earth millions of years ago.

The post Rare parasites found in 200 million-year-old reptile poop appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

WHEN YOU LIVE in a big city, sometimes nature comes at you secondhand—a photo from the apple farm upstate, eggs in the grocery store. But for Miami-born and Brooklyn-based Divya Anantharaman, the founder of Gotham Taxidermy, nature is hardly that binary. “Nature is the pigeon that’s on the sidewalk under the Gowanus Bridge,” they say. “It’s the squirrels you see at the park. It doesn’t exist in this pristine box separate from humanity.”

In their work, nothing is quite binary. In Anantharaman’s fantastical, ethereal creations, the beauty of life is captured after death. In many of the pieces, what you see isn’t strictly textbook science or purely creative. For a two-headed goat kid, the chances of surviving more than a week are one in 3 million according to the World Oddities Expo, which now owns this piece. But in Anantharaman’s work, the joy of being young and alive is frozen in time through anatomical specificity and an artful eye. 

↑ Nobody looks their best after death—including adorable little birds. Here, before skinning it, Anantharaman uses a syringe filled with water and a mild soap to inject a little life into the bird’s eyes and body. 

↑ In all of Anantharaman’s work there is a strong sense of kindness, something that isn’t always seen in the world of taxidermied creatures. Taxidermied bats, for example, are popular trinkets with a questionable ethical background. These lifelike Victorian bats are replicas—the gothic aesthetic with no loss of life. 

↑ The predator-prey dynamic is more than a lion stalking a gazelle on Animal Planet. Small, unassuming creatures must also compete to survive in the life-giving, complex ritual. In a transfixed stare-down between a black-throated magpie and its potential rodent dinner, Anantharaman displays the hunter and the hunted with a sense of tenderness. 

↑ One of the biggest misconceptions about taxidermy, Anantharaman says, is that it’s just embalming. Taxidermy literally means “to move the skin,” they add. This process requires care and delicacy in removing the slightest bones and breakable skull so they can be re-created to reflect a living creature’s symmetry and movement.

↑ Rarities draw us in—a lost antique, a precious gem. For some, that always-out-of-reach prize is a rare or endangered animal. But Anantharaman can still build the unattainable, such as by creating a snowy owl replica using the feathers of chickens and turkeys. With its menacing glower, you’d never know this Arctic predator is a fake.  

↑ Like something out of a fairy tale, a curious fawn steps out into a soft field filled with fruits and flowers. But there is a darker secret to this project—the laminated butterfly wings that gently cover the young deer’s petite frame mirror the real-life attraction of the insects to dead bodies. 

↑ This glowing Chilean flamingo is a work in progress, even if its dignified face would tell you otherwise. The tiny pins along its graceful neck are holding the skin and feathers of its deceased form in place as Anantharaman adds the finishing touches to its wacky, but realistic, final pose. 

↑ Many of the creatures in Anantharaman’s menagerie belonged to no one but themselves, but this cat skull is different. It was once part of an adored pet, whose owner requested this gorgeous, but often taboo, celebration of life. “With pets, you’re not just working on someone’s memories of their animal,” they say. “You’re working on the relationship they had to that animal.” 

↑ In the process between death and rebirth, bits and pieces of an animal can shrink or change. In making a creature as dynamic after death as it was in life, even the finest taxidermists need a little help in the form of a head or leg when the real thing doesn’t do its subject justice. 

↑ The history of taxidermy can be painful, presenting often literal representations of brutality. But for those given the remains of a rare creature, honoring its memory for as long as possible can mean revitalizing what is left of the magnificent beast.

↑ This budgie parakeet, another cherished pet, rests in peaceful slumber just as it did during its life—a bit fluffed out, with a sleepy head tucked under its wing. The beloved bird’s owner was fond of drawing the sweet creature in mystical settings, which Anantharaman re-created with a smattering of soft moss and dainty crystal raindrops. 

↑ Some taxidermy jobs start in the garbage, like this spectacular cassowary. When this mishap was found in a waste facility, not much could be salvaged. But with patience and a hand-sculpted, wrinkle-filled “dinosaur head,” Anantharaman was able to go beyond just restoring its former glory while preserving its traditional essence. 

↑ Owls have what’s called a facial disc, a cupped arrangement of feathers surrounding the eyes. In life, this unique feature helps owls collect sound waves, and the bird can adjust its shape to focus on prey shuffling under snow cover or hiding in plants. Placing the feathers requires patience, impeccable grooming, and a sense of humor. “It’s really funny to see it in this halfway state,” Anantharaman says. “It’s just a little owl in progress.”

↑ In museums and scientific displays, the taxidermied creatures might look far different from the ones we encounter in our day-to-day lives. This project, which Anantharaman is building for a high school, features deceased local birds collected by an enthusiastic (and permitted, of course) teacher who hopes to bring an ecological diorama to the classroom. 

↑ Anantharaman’s workshop is no morgue, but it still requires saws, respirators, and other devices for the rough-and-tumble aspects of taxidermy. Keeping an impeccably organized wall of tools is also emotional for the artist—a celebration of the space they use to create their multidimensional work. 

↑ When you think of an artist’s model, your brain may go to a scantily clad human muse. This starling is certainly nude, but it’s also an expert poser that Anantharaman can move however they like. Once this specimen is out of the freezer, Anantharaman has around 20 minutes to turn it into a dynamic fighter or a stately presence. 

Read more PopSci+ stories.

The post Life after death never looked so beautiful appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Baleen whales like humpbacks, northern and southern rights, and minkes are some of nature’s best known filter feeders. These mammals use the tough keratin baleen plates in their mouths to literally take in huge amounts of water and extract the small organisms like krill or plankton to snack on. However, an ancient reptile may have been the first animal to eat this way. 

[Related: This dolphin ancestor looked like a cross between Flipper and Moby Dick.]

A team of scientists from the United Kingdom and China found some remarkable new fossils that belong to a group of reptiles that were already using filter feeding about 250 million years ago. The findings are described in a study published August 7 in the journal BMC Ecology and Evolution.

Whales are not the only modern day animals to use filter feeding. Fish like basking sharks use their gills to take in food from water. Until now, there has been very little evidence from the fossil record that suggests ancient marine reptiles from the Mesozoic Era (about 252 to 66 million years ago) were filter feeders. 

In this study, the team found two new fossilized skulls that belong to an early marine reptile called Hupehsuchus nanchangensis. The roughly three foot long creature lived in China about 248 million years ago in the Early Triassic period. The high competition for food at this time may have caused H. nanchangensis to develop a specialized feeding system.

“This was a time of turmoil, only three million years after the huge end-Permian mass extinction which had wiped out most of life. It’s been amazing to discover how fast these large marine reptiles came on the scene and entirely changed marine ecosystems of the time,” study co-author and University of Bristol vertebrate paleontologist Michael Benton said in a statement. 

One of the specimens is well-preserved from head to clavicle (collarbone), and the other is a nearly complete skeleton. The team compared the shape and dimensions of the latter skull to 130 skulls from different aquatic animals, including 15 species of baleen whale, 52 species of toothed whale, 23 seal species, 14 crocodilians, 25 bird species, and the platypus. 

They found that Hupehsuchus skulls had soft structures such as an expanding throat region, which likely allowed the reptiles to take in huge amounts of water that had tiny shrimp-like prey, and baleen whale-like structures that filtered the food as it swam forward.  

[Related: Biologists vastly underestimated how much whales eat and poop.]

The Hupehsuchus skulls also have some grooves and notches located along the edge of its jaws that are similar to baleen whales. These present day mammals have keratin strips in their mouths instead of teeth like Odontoceti or toothed whales. 

The mostly complete fossilized skulls also had a long snout composed of unfused and straplike bones, as well as a long space between them and the length of the animal’s snout. This skull shape is only seen in baleen whales and is what allows them to eat krill. 

“We were amazed to discover these adaptations in such an early marine reptile,” study co-author and Wuhan Center of China Geological Survey paleontologist Zichen Fang said in a statement. “The hupehsuchians were a unique group in China, close relatives of the ichthyosaurs, and known for 50 years, but their mode of life was not fully understood.” 

Due to its rigid body, H. nanchangensis was likely a slow swimmer, and this lack of speed suggests that it may have filter fed similarly to today’s bowhead or right whales. These whales swim with their mouths wide open near the surface of the ocean to strain the food from the water. 

These new findings are an example of convergent evolution, a process where similar features evolved independently in different species.

The post The planet’s first filter feeder could be this extinct marine reptile appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Spatial learning is an important and complex skill in the animal kingdom, as it helps animals find a meal when food sources are scarce. Insects such as bees and ants that are social and live in communal nests are known to do this, and now we know some butterflies can as well.  A study published August 7 in the journal Current Biology found that the Heliconius butterfly genus is capable of spatial learning. 

[Related: A ‘butterfly tree of life’ reveals the origins of these beautiful insects.]

According to the authors, the results provide the first known experimental evidence of long-range spatial learning for traplining in any butterfly or moth species. Heliconius or “passion vine” butterflies are tropical butterflies from South and Central America known for a variety of wing patterns. The beautiful creatures have evolved a novel foraging behavior amongst butterflies which includes feeding on pollen that utilizes large scale spatial information, according to the team. 

“Wild Heliconius appear to learn the location of reliable pollen sources and establish long-term traplines,” study co-author and University of Bristol evolutionary neurobiologist Stephen Montgomery said in a statement. “Traplines are learnt foraging routes along which food sources are repeatedly returned to over consecutive days, an efficient foraging strategy similar to the behavior of some orchid bees and bumblebees. However, the spatial learning abilities of Heliconius, or indeed any butterfly, had not yet been experimentally tested.”

In the study, the team conducted spatial learning experiments in Heliconius butterflies over three spatial scales that each represented ecologically-relevant behaviors.  

First, they tested the insect’s ability to learn the location of a food reward in a grid made up of 16 fake flowers. This test represented foraging within a single resource patch.  

Next, the team increased the spatial scale and tested if Heliconius could learn to associate food with either the left or right side of a two-armed maze, to represent multiple plants at a single place.  

Finally, they increased the distances and used a facility of outdoor cages called the Metatron in southern France to test if Heliconius can learn the location of good in a 196 foot wide maze shaped like the letter T. This set up represents foraging between places and is closer to the range Heliconius forages in in the wild. 

[Related: What busy bees’ brains can teach us about human evolution.]

The experiments that the Heliconius does show signs of spatial learning and can memorize the spatial location of their food sources. In future studies, the team plans to test if Heliconius are more proficient spatial learners than closely related species that don’t eat pollen. Understanding this would help reveal how enhanced cognitive abilities can be shaped by an animal’s ecology. 

The team also plans to uncover the unknown mechanisms by which Heliconius navigates. Panoramic views and other visual cues are believed to be important for these butterflies, but the insects may rely on other cues such as a sun or geomagnetic compass in addition to what they can see.  

 “It’s been almost a century since the publication of the first anecdotal story on the spatial capabilities of these butterflies,” study co-author and Universidade Federal do Rio Grande do Norte biologist Priscila Moura said in a statement. “Now we are able to provide actual evidence on their fascinating spatial learning. And this is just the beginning.”

The post Butterflies can remember specific flower foraging routes appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

It’s hard to deny that whales are some of the most charismatic megafauna on our planet. The blue whale, specifically, with its massive size, friendly demeanor, and devastating backstory is one that has captured imaginations for decades. But there may be a new contender for the largest animal to live on earth—or at least there was one around 40 million years ago.

An international team of scientists recently uncovered some giant bones in a fossil-filled coastal desert Peru, namely 13 vertebrae, four ribs and a hip bone. These fossils lead them to a discovery of a sea-dwelling mammal that would’ve weighed up to 340 metric tons. Blue whales have gotten to around 190 metric tons at their heaviest, and the most massive dinosaur, the supersized sauropod Argentinosaurus, was estimated to weigh around 76 tons. 

[Related: Millions of years ago, marine reptiles may have used Nevada as a birthing ground.]

Despite their incredible size, the newly-named Perucetus colossus was likely not a fighter, similar to some of the world’s other favorite sea mammals. 

“Because of its heavy skeleton and, most likely, its very voluminous body, this animal was certainly a slow swimmer. This appears to me, at this stage of our knowledge, as a kind of peaceful giant, a bit like a super-sized manatee. It must have been a very impressive animal, but maybe not so scary,” paleontologist Olivier Lambert of the Royal Belgian Institute of Natural Sciences in Brussels told Reuters. Lambert and his colleagues published their findings August 2 in Nature. 

The chilled-out attitude of the Perucetus was likely not the only thing they had in common with today’s manatees. Its dense, vast skeleton was even estimated to be twice as heavy as a blue whale’s at 5 to 8 tons, even though length-wise, the blue whale still had them beat. 

“It took several men to shift them [the fossils] into the middle of the floor in the museum for me to do some 3D scanning,” author Rebecca Bennion from the Royal Belgian Institute of Natural Sciences in Brussels told the BBC. “The team that drilled into the center of some of these vertebrae to work out the bone density—the bone was so dense, it broke the drill on the first attempt.”

This characteristic doesn’t exist in today’s cetaceans (the family including whales, dolphins and porpoises), but it does appear in sirenians. One author especially noted the Steller’s sea cow, which was discovered in the 1700s only to go extinct within three decades of its discovery due to overhunting. 

[Related: These now-extinct whales were kind of like manatees.]

Like manatees, the Perucetus also appears to have had front limbs. Strangely enough, the animal also possessed vestigial back limbs, a possible evolutionary hangover from when whales evolved from land-based, dog-sized mammals 50 million years ago. 

One looming question about the Perucetus is how it ate—the researchers unfortunately didn’t find it’s skull, so the authors have multiple hypotheses: it may have scavenged, ate sea grass, or even scooped up shellfish and worms from the mud floor like today’s gray whales. 

Nevertheless, just finding a creature that could’ve been this size opens a whole new can of worms for paleontologists to uncover. 

“The extreme skeletal mass of Perucetus suggests that evolution can generate organisms with characteristics that go beyond our imagination,” study author and Italian paleontologist Giovanni Bianucci told CNN. And that is a massive deal. 

The post This giant sea cow-like whale may have been the heaviest creature to ever live on Earth appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Despite lacking blood, a heart, or a brain, slimy jellyfish are one of Earth’s most ubiquitous sea creatures and various species live in all of the planet’s oceans. They are some of the Earth’s oldest animals, having been around for roughly more than 500 million years (that’s 250 million years older than the earliest dinosaurs). Now, scientists with Toronto’s Royal Ontario Museum have found the oldest swimming jellyfish in the fossil record. The discovery of the newly named Burgessomedusa phasmiformis is described in a study published August 1 in the journal Proceedings of the Royal Society B.

[Related: These jellyfish seem to cheat death. What’s their secret?]

Jellyfish belong to a clade of animals called medusozoans, which includes the box jellies, hydroids, stalked jellyfish, and true jellyfish that swim in the oceans today. Medusozoans are part of the group Cnidaria, which also includes sea anemones and corals. The discovery of Burgessomedusa shows that large, swimming jellyfish that are bell or saucer-shaped had already evolved over 500 million years ago.  

Jellyfish are made of roughly 95 percent water, making them tricky to capture in the fossil record. However, the Burgessomedusa fossils are exceptionally well preserved in the Burgess Shale in the Canadian Rockies.  The Royal Ontario Museum now holds close to 200 specimens that were used to learn more about the internal anatomy and tentacles of ancient jellyfish, with some specimens measuring more than seven inches long. Like some modern jellyfish, Burgessomedusa would also have been capable of free-swimming. Their tentacles would have helped it catch pretty big prey.

“Although jellyfish and their relatives are thought to be one of the earliest animal groups to have evolved, they have been remarkably hard to pin down in the Cambrian fossil record. This discovery leaves no doubt they were swimming about at that time,” study co-author and University of Toronto PhD candidate Joe Moysiuk said in a statement. 

This study uses fossil specimens that were discovered at the Burgess Shale during the late 1980s and 1990s. The fossils demonstrate that the Cambrian food chain was much more complex than paleontologists previously believed, and the large swimming arthropods of the time like Anomalocaris were not the only predators. 

[Related: Italian chefs are cooking up a solution to booming jellyfish populations.]

One of the more gnarly parts of the complex life cycle of Cnidarians is that they can have more than one body form. A vase-shaped and non-free swimming body is called a polyp, while medusozoans have a bell or saucer-shaped body–called a medusa or jellyfish–that can be free-swimming or not. Fossilized polyps have been found in about 560-million-year old rocks, but the origin of the more free-swimming medusa or jellyfish is not well understood. Their evolutionary history is primarily based on microscopic fossilized larval stages and molecular studies performed on living species. 

“Finding such incredibly delicate animals preserved in rock layers on top of these mountains is such a wondrous discovery. Burgessomedusa adds to the complexity of Cambrian foodwebs, and like Anomalocaris which lived in the same environment, these jellyfish were efficient swimming predators,” study co-author and Royal Ontario Museum’s invertebrate paleontology curator Jean-Bernard Caron said in a statement. “This adds yet another remarkable lineage of animals that the Burgess Shale has preserved chronicling the evolution of life on Earth.”

The post Jellyfish may have been roaming the seas for at least 500 million years appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Some of our planet’s power pollinators may have originated tens of millions of years earlier than scientists once believed. In a study published July 27 in the journal Current Biology, a team of researchers traced bee genealogy back over 120 million years to the ancient supercontinent Gondwana. This former continent includes parts of present day Africa, Madagascar, South America, Australia, Antarctica, India, and Arabia, and it began to break apart during the early Jurassic period about 180 million years ago. 

[Related: Bee brains could teach robots to make split-second decisions.]

While looking deeper into bee history, the team found evidence that bees originated earlier, diversified faster, and spread wider than previously suspected, putting together pieces of a puzzle on the spatial origin of these pollinators. They likely originated in parts of present day Africa and South America before Gondwana broke apart.

In the study, an international team of scientists sequenced and compared genes from over 200 bee species. They then compared these bees with the traits from 185 different bee fossils and extinct fossils to develop an evolutionary history and genealogical model for how bees have historically been spread around the world. The team was able to analyze hundreds of thousands of genes at a time to make sure that the relationships they inferred were correct.  

“This is the first time we have broad genome-scale data for all seven bee families,” study co-author and Washington State University entomologist Elizabeth Murray said in a statement. 

Earlier studies established that the first bees potentially evolved from wasps, transitioning from predators up to collectors of pollen and nectar. According to this study, bees arose in the arid regions of western Gondwana during the early Cretaceous period, between 145 million years ago to 100.5 million years ago.

“There’s been a longstanding puzzle about the spatial origin of bees,” study co-author and Washington State University entomologist Silas Bossert said in a statement. “For the first time, we have statistical evidence that bees originated on Gondwana. We now know that bees are originally southern hemisphere insects.”

The team found evidence that as new continents formed, the bees moved northward. They continued to diversify and spread in parallel partnership with flowering plants called angiosperms. The bees later moved into India and Australia and all major bee families appear to have split off from one another before the beginning of the Tertiary period (65 million years ago). 

[Related: Like the first flying humans, honeybees use linear landmarks to navigate.]

The team believes that the exceptionally rich flora in the Western Hemisphere’s tropical regions may be due to their longtime association with bees. About 25 percent of all flowering plants belong to the large and diverse rose family of plants, and these beautiful flowers make up a large share of the tropical and temperate hosts for bees. 

The team plans to continue sequencing and studying the history and genetic profiles of more species of bees. Understanding how flowering plants and bees evolved together can help inform conservation efforts for pollinators and how to keep their populations healthy.

“People are paying more attention to the conservation of bees and are trying to keep these species alive where they are,” said Murray. “This work opens the way for more studies on the historical and ecological stage.”

The post The world’s earliest bees may have called Gondwana home appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A group of scientists uncovered a 46,000-year-old soil nematode from Siberian permafrost, and in an Sleeping Beauty-esque experiment woke the microscopic organism up from a millenniums’ long rest. The findings are described in a study published July 27 in the open access journal PLOS Genetics.

[Related: Oyster mushrooms release nerve gas to kill worms before eviscerating them.]

Also called roundworms, nematodes are a very adaptable group of sometimes microscopic animals. In addition to tardigrades and rotifers, some nematodes can survive harsh conditions by entering a dormant state known as cryptobiosis. This process basically shuts down the animals’ metabolic systems until they can be revived when environmental conditions become more favorable. 

After uncovering the animals in Siberia’s northern Kolyma River, the team successfully woke them from this frozen-in-time state. Radiocarbon analysis dated the roundworms to 45,839 to 47,769 years ago, when direwolves and Neanderthals were still on Earth. 

Sequencing the genome revealed that the roundworm is a new species of nematode. Panagrolaimus kolymaensis is a functionally extinct species and joins the ranks of some of Earth’s most ubiquitous organisms that dwell in water, soil, and on the ocean floor. 

“P. kolymaensis‘s highly contiguous genome will make it possible to compare this feature to those of other Panagrolaimus species whose genomes are presently being sequenced by Schiffer’s team and colleagues,” study co-author and Director Emeritus at the DRESDEN-concept Genome Center Eugene Myers said in a statement. 

According to the team, nematodes do not require a lot of coaxing to wake up and wiggle around and make more little roundworms. They have since nurtured more than 100 generations of P. kolymaensis in the lab, where each new generation lasts about 8 to 12 days.

“Basically, you only have to bring the worms into amenable conditions, on a culture (agar) plate with some bacteria, some humidity and room temperature,” study co-author and University of Cologne zoologist Philipp Schiffer explained to Vice. “They just start crawling around then. They also just start reproducing. In this case this is even easier, as it is an all-female (asexual) species. They don‘t need to find males and have sex, they just start making eggs, which develop.”

In addition to the excitement of reviving a species that has been sleeping deep within the earth this long, studying these small spindle-shaped creatures may help scientists better understand how animals can adapt to habitat changes due to global warming and shifting weather patterns at a molecular level. 

[Related from PopSci+: Cave worms could hold the secrets to a better life.]

They found that mild dehydration exposure before freezing helped P. kolymaensis prepare for cryptobiosis and increased survival at -112 degrees Fahrenheit. The nematodes produced a sugar called trehalose when it was mildly dehydrated in the lab, potentially enabling it to endure these freezing and intense dehydration. 

“Our findings are essential for understanding evolutionary processes because generation times can range from days to millennia and because the long-term survival of a species’ individuals can result in the re-emergence of lineages that would otherwise have gone extinct,” study Schiffer said in a statement. 

The post Recently awoken 46,000-year-old nematodes already have 100 generations of babies appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A flattened—but still mostly complete—turtle fossil from the late Jurassic period was just unearthed in present-day Germany. Now, the flat-as-a-pancake specimen of Solnhofia parsonsi is helping paleontologists learn more about how these reptiles evolved and lived in the more shallow marine ecosystems.The findings were described in a study published July 26 in the journal PLOS ONE.

[Related: Gigantic fossils hint at super-sized 7,000-pound sea turtle.]

“The very good preservation of the fossils in the layers of limestone can be explained by the environmental conditions at the time,” co-author and University of Tübingen paleoecologist Andreas Matzke said in a statement. 

S. parsonsi lived in a Bavaria that looked and felt quite different from the region today. About 150 million years ago, the region in southern Germany near Munich was a shallow tropical archipelago with spongey reefs around it. When animals like S. parsonsi died in these salty and low oxygen bodies of water, scavengers had a difficult, if not impossible, time picking apart their remains, leading to well preserved specimens like this turtle pancake. 

As demonstrated by this specimen, the turtle’s forelimbs and hind limbs are comparatively short, which suggests that it lived near the coast. This differs from today’s sea turtles, who have long flippers and live in the open sea. 

“No Solnhofia individual with such completely preserved extremities has ever been described before,” study co-author and paleontologist at the University of Tübingen Felix Augustin said in a statement. 

The turtle’s head and carapace (upper back) are also clearly preserved in the fossil. S. parsonsi had a long and pointed beak and a triangular heat that was about 3.5 inches long.

“Solnhofia may have used its large head to crush hard food items such as shelled invertebrates, as we see in some modern turtles, but it does not mean these were exclusively forming its diet,” said co-author and University of Tübingen paleontologist Márton Rabi said in a statement.

[Related: Hungry green sea turtles have eaten in the same seagrass meadows for about 3,000 years.]

The diamondback terrapin is the closest modern analogue to S. parsonsi. This somewhat salt tolerant turtle with a diamond pattern on its shell lives in brackish estuaries in the East Coast of the United States.  

S. parsonsi is not the first notable fossil uncovered in the limestone deposits of Solnhofen, a spot south of the city of Nuremberg in the valley of the Altmühl. Paleontologists have dug up fossils of some of the earliest birds called Archaeopteryx and numerous pterosaurs and other marine reptiles. This area is also considered one of the most important sites for Mesozoic fossils, which began about 250 million years ago and lasted until the extinction of the dinosaurs roughly 66 million years ago. 

The post 150 million-year-old turtle ‘pancake’ found in Germany appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Picture this: Two dinosaurs with massive teeth and hulking figures circle each other, threatening a smackdown. Each was the most successful predator of its time. In a ferocious duel of the dinosaurs—Tyrannosaurus rex vs. Giganotosaurus carolinii—which would emerge alive? 

Both species enter the ring with experience as apex predators that hunted some seriously impressive prey. T. rex is thought to have eaten armored Triceratops and big-brained duck-billed dinosaurs, while Giganotosaurus probably took down the largest-ever land animals: the long-necked sauropod dinosaurs, which could’ve been 10 times the predator’s size. None of these dinos would’ve been an easy meal. So what would happen if the two fearsome Cretaceous carnivores were to face off against each other?

But pitting the two against each other serves to highlight their differences, says Thomas Holtz, a principal lecturer in vertebrate paleontology at the University of Maryland who studies tyrannosaurs and their motion. This kind of thought experiment might lead to a better understanding of how these creatures followed their own evolutionary paths to become distinct, highly successful predators. 

Some of those differing characteristics might be advantageous in a rumble. But in a one-on-one fight, there is unlikely to be an obvious champion and an underdog, says Kat Schroeder, a paleomacroecologist and postdoctoral research associate at Yale University.

“They’re not fighter jets,” she says. “You can’t say this one has this absolute top speed. They’re animals. And they’re animals that lived 30 million years apart on different continents. They’re separated by 150 million years of evolution [since their last shared ancestor].”

[Related: Jurassic Park fans would love these dino discoveries]

Holtz agrees that it could be any dinosaur’s game, despite admitting professional and personal bias toward tyrannosaurs (when he was 3, he wanted to grow up to be one). “Both of them are big predators adapted to killing very large prey,” he says. “If either of them managed to get a good bite onto the other one first, they’re probably going to win.” 

What’s in a bite?

T. rex and Giganotosaurus can be described as “head hunter theropods,” Schroeder says. They both had “teeny, tiny little arms and giant heads,” she says, “so they’re probably not going to be pulling and scratching at one another.” Kicking is also out, because their feet would probably be too heavy to be of use in a fight. So there’s only one remaining option with any teeth. “They’re basically going to walk up to one another and try to grab each other with their giant mouths,” she says.

Both predators’ bites are vicious in different ways. T. rex can deliver the most skull-crushing of chomps, while Giganotosaurus’ bite leverages sharp, blade-like teeth to slash its prey’s flesh. 

T. rex’s bite force is “almost off the scale,” says Holtz. The lowest estimates for an adult’s bite force are around 34.5 kilonewtons, he says, “which is twice as strong as the bite of a saltwater crocodile, the largest reptilian predator of today.” 

[Related on PopSci+: What dinosaur fossils are we missing?]

Several adaptations in a T. rex’s head enable that smashing crunch. For one, the tyrant lizard has a long, deep snout made up of thick jaw bones, with very deeply rooted teeth. From above the gums, T. rex and Giganotosaurus would’ve appeared to have the same size teeth. But the roots of T. rex’s teeth, Holtz says, were double those of a Giganotosaurus tooth, which could be around 8 inches in total length. The largest known T. rex teeth reach 12 inches, and they’re built for impact with a round, thick shape. “T. rex has a jackhammer for a mouth,” Schroeder says. 

The T. rex’s snout was also made up of somewhat flexible bones, Schroeder says, which can be an advantage for a big bite. “A little bit of springiness allows you to bite really, really hard without breaking your own face.” 

Giganotosaurus, on the other hand, had a more forceful nip at the front of its mouth, with a long and slender snout about three times as long as it was tall. Its sharp, blade-like teeth were better at cutting than chomping down. Giganotosaurus teeth could ably slice through meat and might have been able to cause a lot of damage with a small nip.

But these dinosaurs likely wouldn’t just take turns biting each other, even locked in a cage fight. Their body size and nimbleness would also come into play.

Agility of the fighters

Jurassic Park’s Alan Grant was incorrect when he said Giganotosaurus was the largest carnivore ever to roam the Earth (that crown goes to Spinosaurus), but it was likely larger than a T. rex—at least in length. Giganotosaurus was probably about 45 to 47 feet long, while the largest T. rex specimen reached nearly 42 feet long (nicknamed “Scotty,” its bones reside at Canada’s Royal Saskatchewan Museum). Both stood about 20 feet tall, and Giganotosaurus may have had a few tons of mass on T. rex, but estimates for their maximum masses are both upward of 9 tons. 

Still, it’s unlikely that such a small size difference would give one dinosaur an edge over the other, says Holtz. What might have put T. rex in the lead, he says, was its weight distribution and resulting agility.

T. rex’s weight is concentrated toward its middle, while Giganotosaurus is “more long and slab-like throughout its body,” he says. Holtz and colleagues calculated that a T. rex could rotate its body and twist in place twice as well as other dinosaurs of a similar mass, thanks in part due to massive hip bones and muscles. The pyramid-shaped ankle bones of a T. rex also may have offered more stability for maneuvering than a Giganotosaurus’s boxier ankles, Schroeder says. “T. rex might have been able to corner a little bit better.”

Two aspects of tyrannosaurus’s evolution might explain these adaptations, Holtz suggests. T. rex’s ancestors were smaller—the ones that were around when Giganotosaurus roamed Earth were “basically dinosaurian coyotes,” he says. Or perhaps they evolved these traits to take down sophisticated prey. Triceratops, for example, was “one of the most heavily armed herbivores in Earth history,” he says, and duck-billed dinosaurs had one of the largest brain-to-body size ratios of any herbivorous dinosaur. T. rex had a bigger brain than Giganotosaurus, Holtz says, probably because it had to hunt speedier, more agile prey.

Giganotosaurus brains were half the size. “You don’t have to have a lot of focus if you’re going after walking walls of meat,” Holtz says. They came from a long line of giant predatory dinosaurs. Their “basic body plan” prepared them to hunt “long, slow-moving” herbivores, such as stegosaurs and sauropods.  

[Related: The longest dinosaur neck ever found in the fossil record]

Defeating a sauropod, which lived in a pack and may have grown up to 80 tons, would not have been easy, however, says Schroeder. Even picking off a small, young herbivore would’ve been tricky. “You’re not rolling up on a group of elephants and just grabbing a juvenile,” she says.  “You’re going to have to face off with one of these enormous animals.” 

It’s possible that this is where the slashing kind of bite comes in handy for Giganotosaurus, Holtz says. Maybe it could deliver a fatal bite quickly, he says, or perhaps its blade-like teeth could weaken the massive prey, so the carnivore could track it down to go for the kill at the right moment. 

That might be how Giganotosaurus could get the first bite on T. rex, too. The tyrant lizard had both of its eyes on the front of its face, offering better depth perception, Holtz says. But Giganotosaurus’s eyes, more toward the sides, gave better perception around their bodies. The giant southern lizard might be able to sneak-attack the T. rex, sinking its sharp front fangs into its opponent’s flank. 

If the battle occurred in one of the creatures’ home habitats, instead of in a neutral environment, that would add another dimension, Schroeder says. On Giganotosaurus’ turf, for example, T. rex might struggle with the heat and dryness of the desert in what is present-day Argentina.  

These environments, and the prey who lived there, shaped how these dinosaurs evolved. During Giganotosaurus’s time, the environment was changing dramatically with the emergence of diverse flowering plants. By the time T. rex came on the scene, however, the environment was much more stable—right up until a big rock smashed into the planet. 

There’s also a lot that remains unknown about both dinosaurs, but especially Giganotosaurus, Schroeder says. Paleontologists have found fewer of its fossils, and discuss it less frequently at conferences, likely because its homeland of South America gets less scientific attention and funding. “Paleontology tends to be a little bit North America-centric,” she says. And while “it’s fun to talk about these questions” of who would win in a fight, “we wouldn’t have any answers if we didn’t have fantastic scientists working down in South America and Africa.”

The post Giganotosaurus vs. T. rex: Who would win in a battle of the big dinosaurs? appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Deep beneath our feet almost anywhere on the planet, there are parasitic spaghetti-like puppet masters known as horsehair worms or gordian nematodes. 

These sneaky, slimy beings are lacking three major systems: excretory, circulatory or respiratory. To make up for it, they invade crickets, grasshoppers and other invertebrates, tapping into their neurological circuit and eventually brainwashing them. Once inside a body, the adult worm will then take action by controlling their host and forcing them to seek a water body so that the worms can exit and mate. 

[Related: Mind-controlling ‘zombie’ parasites are real.]

These creatures might not just be missing crucial systems for function—but something in their DNA.  Scientists from the Field Museum of Natural History and Harvard University sequenced the genome of the freshwater hairworm Acutogordius australiensis and the saltwater worm Nectonema munidae. They discovered that these animals were missing genes that coded for cilia—hair-like structures found on nearly all cells in animals and humans. 

The researchers published their findings in Current Biology this month.   

“What we found, which was very surprising, was that both hairworm genomes were missing about 30 percent of a set of genes that are expected to be present across basically all groups of animals,” said Tauana Cunha, a postdoctoral researcher at Chicago’s Field Museum and lead author of the study

Cilia are the fuzzy hair-like threads found on eukaryotic cells that help with moving fluid, debris and other materials from one place to another. “Animals use ciliary structures to move, to clean their cells, as sensors (there are cilia in your eyes and ears, for example), in sperm cells. Sponges use these structures to move water and feed, we use them for many of the things,” says co-author Bruno de Medeiros, research associate at the Museum of Comparative Zoology at Harvard University and assistant curator of insects at the Field Museum. “It is crazy that an animal would lose cilia and flagella, since they seem so useful and so entangled into the natural history of an animal.”

The lineage of hairworms has historically been understudied. Hairworm experts are limited, and delving into their genome is an expensive and uncommon process. But, these findings open up a new series of questions over what other creatures may have lost “such a fundamental cell-level structure as the cilia,” Mederios says. 

“So this major lineage of animals was neglected so far. There are others, still. We definitely do not have yet a clear picture of the genome of all animals,” says Mederios. 

[Related: How a peculiar parasitic plant relies on a rare Japanese rabbit.]

While humans don’t need to live in fear of a mind-controlling worm, knowing how these parasites operate is crucial to protecting environmental and human health. For example, the saltwater species sampled was found in a deep-sea lobster, which can be caught for human consumption. Other arthropods pollinate crops, or are even used in feedstocks or experimental human food. 

“If the trend to use crickets as food keeps up and we start to do mass-production of crickets, we certainly want to be aware of the potential parasites and how to deal with them, which include hairworms,” Mederios says. 

The post ‘Brainwashing’ parasites inherit a strange genetic gap appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Our early human ancestors were a pretty busy bunch, cooking up brown crabs in caves in Portugal, mastering archery, and even taking on weaving. They may have been master woodworkers. According to a study published July 19 in the journal PLOS ONE, a 300,000-year-old wooden hunting weapon was scraped, seasoned, and sanded before it was used to kill animals. This new finding indicates that early human woodworking techniques were more sophisticated and developed than scientists once believed. Creating lightweight weapons may have enabled group hunts of smaller and medium sized animals. 

[Related: Women have been skillful, purposeful hunters in most foraging societies.]

The two-and-a-half foot long stick was first discovered in Schöningen, Germany in 1994 alongside other tools including throwing spears, thrusting spears, and a second throwing stick that was similarly sized. This new study used some of the advances in imaging techniques that have emerged in the almost three decades since the stick’s discovery—micro-CT scanning, 3D models, and 3D microscopy—to take a closer look.

“Our study confirms that this tool is the earliest known ‘throwing stick’, which is a weapon that was thrown rotationally, similar to a boomerang,” co-author and University of Reading palaeolithic archaeologist Annemieke Milks tells PopSci. “The slight curve of the tool, as well as how it was shaped to have more mass towards one half, rather than in the middle, would have helped it to rotate. We think that it might have been thrown at distances as far as 30 meters [98 feet].”

The stick was most likely used to hunt medium sized game such as red and roe deer, and potentially quicker and smaller prey including birds and hare. It likely would have been thrown like a modern day javelin. While it is lightweight, the high velocities at which these weapons can be launched could have resulted in some deadly high-energy impacts.

The carefully shaped points, fine surface, and polish from handling also suggested that it was part of a personal kit that was repeatedly used, instead of a quickly made tool that was thrown away. The 3D microscopy and micro-CT scanning helped the team identify all of the building steps, including how the bark was removed, how the two points were shaped, and how the wood was worked away to force a more aerodynamic weapon.

“We were really excited to see just how many steps and how detailed the woodworking is on this tool. We could also see that they sanded the surface to make it finely finished, and that some polish shows they used this tool for a really long time. This was a tool that was beautifully crafted and used for some time,” says Milks.

[Related: Archery may have helped humans gain leverage over Neanderthals.]

These early hunting weapons can also be thought of as tools that whole communities would use. Footprints belonging to both adults and children have been discovered at Schöningen, indicating that children were present at this site. At this time, hunting was key to survival, some children as young as three or four would learn to throw and use weapons and girls and women likely weren’t excluded from learning these crucial skills.

“In some societies, they start hunting in groups of kids, without any adults at all, and then in their teenage years they start hunting larger animals,” says Milks. “Although we don’t know for sure who threw this weapon, smaller tools like this throwing stick may have been particularly well-suited for kids to learn with.”

The stick is currently on display at the Forschungsmuseum Schöningen.

The post A javelin-like stick shows early humans may have been keen woodworkers appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A fossilized skull first discovered 18 years ago turns out to belong to a new species of extinct alligator from Thailand called Alligator munensis (A. munensis). Named after the nearby Mun River, the new species is closely related to the Chinese alligator. Researchers from institutions in Germany and Thailand described this new finding in a study published July 13 in the journal Scientific Reports.

[Related: A rare, 95-million-year-old titanosaur skull found in Australia.]

The team dated the skull to younger than 230,000 years old and was found in Ban Si Liam in southern Thailand. It has some features that differentiate it from modern alligator species, including a short and broad snout, a tall skull, and fewer teeth than other alligators its size. A. munensis’ large tooth sockets towards the back of its mouth indicate that its large teeth may have been able to crush shells and snack on hard-shelled prey like snails and other animals.   

The skull is also about 9 inches in length, an indication that this ancient reptile was not very large.

“The skull was really bizarre,” co-author and evolutionary biologist at the University of Tübingen in Germany Márton Rabi told New Scientist. “It was screaming that it has to be a new species.”

They investigated the evolutionary relationships of A. munensis by comparing its remains with 19 specimens from four extinct alligator species, alongside some living alligator species including the American alligator, Chinese alligator, and the spectacled caiman. The researchers also reviewed previously published research on the skeletal characteristics of, and evolutionary relationships between, alligator species.

There are some similarities between the skulls of A. munensis and the present day Chinese alligator, which is primarily found in the Anhui and Zhejiang provinces of eastern China. Both species have a small opening in the roof of the mouth, a ridge on the top of the skull, and a raised ridge behind their nostrils. 

[Related: Why scientists gave vaccines to farmed crocodiles.]

The team believes that these extinct and living species are closely related, and likely shared a common ancestor that lived in the lowlands of the Yangtze-Xi and Mekong-Chao Phraya river systems. A. munensis and the Chinese alligator may have evolved independently due to increases in the elevation of the southeastern Tibetan Plateau between 23 and 25 million years ago.

“One of the more intriguing questions is to know when was more precisely the time of the split between A. munensis and A. sinensis [Chinese alligator],” study co-author and researcher at Eberhard Karls Universität Tübingen Gustavo Darlim, told Gizmodo. “We are currently working on developing this analysis that would help us to better understand not only how Alligator got to Asia, but also the dispersal of Alligator within Asia.”

The post Extinct snub-nosed gator had big teeth for crushing snails appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

For annulated sea snakes, seeing the wonderful world of color wasn’t always possible. These venomous sea snakes that roam Australia and Asia’s oceans once lost their color vision, but a new study into their genomes reveals that they have potentially regained their ability to see a wider palette of colors over the last 100 million years. The findings were published July 12 in the journal Genome Biology and Evolution, published by Oxford University Press.

[Related: A guide to all the places with no snakes.]

For animals, normal color vision is mostly determined by genes called visual opsins. Multiple losses of opsin genes have occurred as tetrapods—a group including amphibians, reptiles, and mammals—have evolved. The emergence of new opsin genes is significantly more rare than losing them. A 2020 study found that some semi-aquatic snake species in the genus Helicops found in South America are the only known snakes to regain these opsin genes.

“The ancestral snake, which is the original snake species, lost the capacity for advanced color vision ~110 million years ago. This was because they likely dwelt in dim-light environments where visual perception would be limited,” study co-author and University of Adelaide PhD student and marine biologist Isaac Rosetteo tells PopSci.

This ancestral snake species lived on the land and would later evolve into all snake species, including sea snakes. When their genes for color vision were gone, they could only perceive a very limited range of colors. However, that likely started to change as some elapid descendants began to change. Within the last 25 million years, two elapid lineages have moved from terrestrial to marine environments.

With the fully sequenced genome of the annulated snake in hand, the team in this new study from the University of Adelaide in Australia, The University of Plymouth in the United Kingdom and The Vietnamese Academy of Science and Technology looked at visual opsin genes in five ecologically distinct species of elapid snakes. Elapids are the family of about 300 venomous snakes that include mambas, cobras, and the annulated sea snake. Looking at this family more broadly offered an opportunity to investigate the molecular evolution of vision genes. 

The team found that the annulated sea snake now has four intact copies of the opsin gene SWS1. Two of these genes are sensitive to ultraviolet light that has shorter wavelengths, while the other two genes have evolved a new sensitivity to the longer wavelengths of light that dominate ocean habitats. 

“Only one [of these genes] was expected. To our knowledge, every other ~4000 snake species in the world (except a couple of Helicops species) have just one of these genes. The most interesting part is that two of these genes allow for perception of UV light, while the other two allow for the perception of blue light. This is expected to dramatically increase their sensitivity to colors which could be very useful in bright-light marine environments,” says Rosetto.

The authors believe that this sensitivity means that the snakes could have color discrimination that allows them to distinguish predators from prey, as well as potential snake mates against the more colorful background in the ocean.  

[Related: How cats and dogs see the world.]

This significantly differs from the evolution of opsins in mammals like bats, dolphins, and whales during their own ecological transitions. These mammals saw more opsin losses as they adapted to dim-light and aquatic environments.

“Our own primate ancestors developed the advanced color vision we enjoy via a similar mechanism. Their long-wavelength-sensitive opsin was duplicated, and one copy changed to allow for perception of a different wavelength of light than the original,” says Rosetto. “These snakes have done the exact same thing, just with a different visual opsin and there are now four copies instead of just two. Without these duplications, our (and their) capacity for color vision would be heavily reduced.”

The post Some sea snakes may not be colorblind after all appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A rare, half-billion-year-old fossil gives us a clue to how a bizarre marine invertebrate can possibly be related to humans. In a study published on July 6 in the journal Nature Communications, Harvard University researchers identified a prehistoric specimen in a collection at the Natural History Museum of Utah as a tunicate, or sea squirt. The preserved invertebrate, which was originally discovered in the rugged, desert-like landscape of the House Range in western Utah, can be used to understand evolution mysteries that go way back to the Cambrian explosion. 

“There are essentially no tunicate fossils in the entire fossil record. They’ve got a 520- to 540-million year-long gap,” says Karma Nanglu, an invertebrate paleontologist at Harvard. “This fossil isthe first soft-tissue tunicate in, we would argue, the entire fossil record.”

Sea squirts can be seen swaying on the ocean floor with its potato-like body and two chimney-like parts called siphons that are used to feed and expel water. While there are at least 3,000 different species today, the crayon-point-size organisms are generally unknown to people—despite being our invertebrate cousins, says Nanglu. Like humans, they belong to the chordates, which share five essential physical features during development or when fully grown. Most tunicates hatch as swimming, tadpole-like creatures, but eventually attach to the ocean floor and lead a sessile lifestyle.

[Related: Fossil trove in Wales is a 462-million-year-old world of wee sea creatures]

The soft-tissue fossil that Nanglu studied from the Natural History Museum of Utah was unidentified, but surprisingly well-preserved. After nearly 10 hours of testing, dissecting, and comparing to modern sea squirts, he was sure it was a tunicate based on its siphons, tubular body, and unique markings. He and his team named the specimen Megasiphon thylako and estimated that it was around 500 million years old, putting it near the end of the Cambrian explosion, when evolution hit record levels. With this little specimen, Nanglu says can tell researchers more information about the history of tunicate divergence and even our own. 

“What the fossil shows is the assumption that tunicates did arise after the Cambrian period,” says Robert Gains, a professor at Pomona College in California who specializes in Paleozoic geology and geochemistry of the western US. “The evidence is so strong that it may place them back further, which has happened with lots of other animals as well.”

One of the big questions for tunicate origins centers on what the last common ancestor of the group looked like. This was part of what directed Nanglu to investigate the House Range specimen. Among the most prominent features on Megasiphon thylako, he says, were the dark, concentrated bands that ran from the base of the body, all the way to the tip of the siphons. The researchers describe it in the paper as “this almost pitchfork-like arrangement … they almost look like a circulatory system as found in modern tunicates.”

When comparing the fossil to  present-day tunicates from other laboratories such as the Marine Biological Laboratory in Woods Hole, Massachusetts, the teams saw a similar arrangement that they interpret as muscles in the ancient species. “You can see how comparable the modern and old tunicate are,” Nanglu says. 

With all the evidence laid out before him, Nanglu remained cautious about calling the specimen a tunicate at first. “We’re making a pretty substantial claim here. A group that essentially has no fossil record, and we’re saying this is the first one from that group.” Even after completing the study, he says he remains shocked and fascinated by this rare discovery. 

“I can’t believe this thing was preserved. I can’t believe we have good evidence of the musculature of a thing that’s 500 million years old. I can’t believe we’re getting a look at the undersea world from half a billion years ago. So hopefully people will just be kind of amazed by just the scope of some of those components of the story.”

[Related on PopSci+: The ghosts of the dinosaurs we may never discover]

Utah, which was located near the equator during the Paleozoic era, was a hotbed for animal diversification. Sea squirts and other millions-year-old marine fossils can be found in abundance in the western part of the state. Megasiphon thylako aids understanding in not only the evolution of certain groups and species, but also the entire Marjum Formation. 

“I think this discovery really shows the power of the fossil deposit that the authors are working on,” Gains says. “I think that continued exploration of that fossil deposit is going to pay big dividends into the future for our understanding of the origins of animals and in our understanding of the Cambrian period.”

The post A 500-million-year-old sea squirt is the evolutionary clue we need to understand our humble beginnings appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

The phrase “busy as a bee” certainly applies to the brains of honey bees. The insects have to balance effort, risk and reward, avoid predators, and make accurate assessments of which flowers are the most likely to offer food for their hive while they fly. Speed and efficiency are thus critical to their survival, and scientists are taking a look at their brains to understand how. A study published June 27 in the journal eLife explores how millions of years of evolution engineered honey bee brains to make these lightning fast decisions and reduce their risks. 

[Related: What busy bees’ brains can teach us about human evolution.]

“Decision-making is at the core of cognition. It’s the result of an evaluation of possible outcomes, and animal lives are full of decisions,” co-author and comparative neurobiologist  at Australia’s Macquarie University Andrew Barron said in a statement. “A honey bee has a brain smaller than a sesame seed. And yet she can make decisions faster and more accurately than we can. A robot programmed to do a bee’s job would need the backup of a supercomputer.”

Barron cites that today’s autonomous robots primarily work with the support of remote computing, and that drones have to be in wireless communication with some sort of data center. Looking at how bees’ brains work and could help design better robots that explore more autonomously. 

In the study, the team trained 20 bees to recognize five different colored “flower disks.” The blue flowers always had a sugar syrup, while the green flowers always had tonic water that tasted bitter to the bees. The other colors sometimes had glucose. Then, the team introduced each bee to a makeshift garden where the flowers only had distilled water. Each bee was filmed and the team watched over 40 hours of footage, tracking the path the insects took and timing how long it took for them to make a decision. 

“If the bees were confident that a flower would have food, then they quickly decided to land on it, taking an average of  0.6 seconds,” HaDi MaBouDi, co-author and computational neuroethologist from the University of Sheffield in England, said in a statement. “If they were confident that a flower would not have food, they made a decision just as quickly.”

If the bees were unsure, they took significantly more time–1.4 seconds on average–and the time reflected the probability that a flower contained some food.

Next, the team built a computer model that aimed to replicate the bees’ decision-making process. They noticed that the structure looked similar to the physical layout of a bee’s brain. They found that the bees’ brains could make complex autonomous decision making with minimal neural circuits. 

[Related: A robot inspired by centipedes has no trouble finding its footing.]

“Now we know how bees make such smart decisions, we are studying how they are so fast at gathering and sampling information. We think bees are using their flight movements to enhance their visual system to make them better at detecting the best flowers,” co-author and theoretical and computational biologist at the University of Sheffield James Marshall said in a statement. 

Marshall also co-founded Opteran, a company that reverse-engineers insect brain algorithms to enable machines to move autonomously. He believes that nature will inspire the future of the AI industry, as millions of years of insect brain evolution has led to these incredibly efficient brains that require minimal power. 

The post Bee brains could teach robots to make split-second decisions appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Same-sex sexual behavior has been documented in over 1,000 animal species—from nematode worms to penguins to cattle. While few animals are exclusively homosexual across the animal kingdom, same-sex sexual interactions are more common than once believed and are potentially beneficial evolutionarily. For one population of male macaques, same-sex sexual behavior has evolved with—and may be a common feature of—reproductions in primates, according to the results of a study published July 10 in the journal Nature Ecology and Evolution.

[Related: Why do some animals engage in same-sex sexual behavior? The better question is… why not?]

“We found most males were behaviourally bisexual, and that variation in same-sex activity was heritable,” co-author and Imperial College London ecologist Jackson Clive said in a statement. “This means that the behavior can have an evolutionary underpinning; for example, we also found that males that mounted each other were also more likely to back each other up in conflicts—perhaps this could be one of many social benefits to same-sex sexual activity.”

In the study, the team examined 236 males within a colony of 1,700 rhesus macaques living freely on the island of Cayo Santiago, Puerto Rico. In addition to observing their behavior, the team conducted genetic analyses and had access to pedigree records. These records detail the parentage of each individual money back to 1956. 

The team recorded all social ‘mountings’ for all of the 236 males, including different-sex behavior (DSB, or male-on-female) and same-sex behavior (SSB, or male-on-males). Male same-sex mounting occurred in 72 percent of sample males, compared to only 46 percent of the male population participating in different-sex mounting. 

Some theories about SSB in animals believe that it has to do with establishing dominance within groups, handling a shortage of different-sex partners, or reducing tension following aggressive behavior.  

The study team investigated several of these prevailing theories and found that SSB with males was strongly correlated with “coalitionary bonds” in this community. This means that the male pairs that regularly engage in SSB were more likely to support one another in conflicts and  provide an advantage within the social group. 

When the team looked to see if SSB led to any reduction in offspring, they found that the males engaged in SSB may actually be more successful in reproducing. This could be due to those social benefits provided by more coalitionary bonds.

Using the pedigree data, they found that SSB was 6.4 percent inheritable, showing evidence of a genetic link to primate SSB outside of humans. This percentage is similar to other heritable behaviors in primates including grooming and sociality.

[Related: Super semen could be one reason why primates evolved to masturbate.]

They also found some genetic correlation between the males that were more often ‘mounters’ or ‘mountees’ when engaging in SSB. This suggests that these sub-behaviours may have a common basis. Additionally, whether or not individuals were more likely to be mounters or mountees did not correlate with their social position, according to the authors. They believe that asserting their place within the hierarchy is not an important factor for SSB in this species. 

The study suggests that some degree of SSB can evolve as an adaptive behavior, depending on the context, and may be a common feature or reproductive ecology in primates. 

“Unfortunately there is still a belief amongst some people that same-sex behavior is ‘unnatural,’ and some countries sadly still enforce the death penalty for homosexuality,” co-author and Imperial College London biologist Vincent Savolainen said in a statement. “Our research shows that same-sex behavior is in fact widespread amongst non-human animals.

The post Same-sex mounting in male macaques can help them reproduce more successfully appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

At first glance, the extinct apex predator Anomalocaris canadensis (A. canadensis) looks like it would have been a formidable foe. However, new biochemical studies on the arachnid-like front appendages on the two-foot long marine animal were likely weaker than scientists first assumed. The analysis is described in a study published July 4 in the journal Proceedings of the Royal Society B, and found that A. canadensis was possibly agile, fast, and darted after soft prey in open water instead of the harder shell creatures on the ocean floor.

[Related: This ancient ‘mothership’ used probing ‘fingers’ to scrape the ocean floor for prey.]

A. canadensis was one of the largest animals to live 541 million to 530 million years ago during the Cambrian Period. This remarkable era in the planet’s history is when numerous invertebrates and the first vertebrates (fish) appeared in the fossil record. This period of extraordinary evolution is often referred to as the Cambrian explosion due to all of the new life that emerged in the cooler temperatures and tectonic changes of the Cambrian. 

Roughly translating to “weird shrimp from Canada” in Latin, A. canadensis’ was initially discovered in 1892. Since then, scientists have believed it was responsible for some of the scarred and crushed exoskeletons from trilobites that paleontologists have found in the fossil record. 

“That didn’t sit right with me, because trilobites have a very strong exoskeleton, which they essentially make out of rock, while this animal would have mostly been soft and squishy,” study co-author and American Museum of Natural History invertebrate paleontologist Russell Bicknell said in a statement. 

Some additional research on A. canadensis’ armor-plated, ring-shaped mouthparts lays doubt on its ability to process hard food. This new study set out to see if the predator’s long front ‘legs’ could do this instead of its mouth. 

The team first built a 3D reconstruction of A. canadensis from flattened yet well-preserved fossils that have been found within Canada’s 508-million-year-old Burgess Shale. They used present-day whip scorpions and whip spiders as a comparison, and showed that A. canadensis’ segmented appendages could grab prey and also stretch out and flex.

[Related: These weird marine critters paved the way for the ‘Cambrian explosion’ of species.]

They then used a modeling technique called finite element analysis to demonstrate the stress and strain points on this grasping behavior. The researchers found that its appendages would have been damaged while grabbing onto hard prey like trilobites. Computational fluid dynamics was then used to put the 3D model of the predator into a virtual ocean current to predict what body position A. canadensis likely would have used while swimming in Cambrian seas. 

This mix of biomechanical modeling techniques cast A. canadensis into a whole new light. It was probably a speedy swimmer that went after soft prey in the water with its front appendages outstretched for the grab. 

“Previous conceptions were that these animals would have seen the Burgess Shale fauna as a smorgasbord, going after anything they wanted to, but we’re finding that the dynamics of the Cambrian food webs were likely much more complex than we once thought,” Bicknell said.

The post Ancient ‘weird shrimp from Canada’ used bizarre appendages to scarf up soft prey appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

One of the most persistent myths that reinforces traditional gender roles and binaries is the idea that men are best slated to work outside the home due to their nature as hunters, while women are more suited to domestic life to their role as gatherers. A study published June 28 in the open-access journal PLOS ONE is turning that myth on its head once again, finding that women hunt in at least 79 percent of past and present foraging societies. 

[Related: A female hunter’s remains hint at more fluid gender roles in the early Americas.]

Despite the persistence of the myth that women were largely plant gatherers, archaeological evidence from across human history and prehistory shows evidence to the contrary. For example, the remains of women from societies have been found buried alongside big-game hunting tools, including a 9,000 year old burial located in Peru. The woman buried there had a hunting toolkit with stone projectiles as well as animal processing equipment buried alongside her. 

To look further into the possibility that foraging societies didn’t follow those gender roles quite as strictly as we once believed, the team analyzed data from the past century on 63 foraging societies around the world. This covered societies in North and South America, Africa, Australia, Asia, and the Oceanic region.

The team found that regardless of their maternal status, women hunt in 79 percent of the societies they studied.  Over 70 percent of female hunting also appears to be intentional, instead of opportunistic killing of animals encountered while doing other activities. Women’s intentional hunting appears to target game of all sizes, but was most often large game.

“I think we all expected to find the evidence that women hunted; what was surprising was how many women ‘purposefully’ hunt,” study co-author and Seattle Pacific University biological anthropologist Cara Wall-Scheffler tells PopSci. “We were expecting to find evidence that women hunted ‘opportunistically’ (only hunting if they happened across prey while they were out and about), but it ends up that in many places, women go out with the intention of hunting.”

Their analysis also showed that women are actively involved in teaching how to hunt, and that they use a greater variety of weapons and hunting strategies than their male counterparts. They cite the Agta women from the Philippines as an example. Agta men typically heavily rely on a consistent strategy of bow and arrows, while women are much more likely to have personal preferences and show variation in tools. Some of the women prefer hunting with only knives, others use bows and arrows, and some use a combination of the two.

[Related: How to use science to talk to kids about gender.]

According to the team, their findings further support the idea that women are skilled at hunting and play an instrumental role in the practice in many foraging societies. Additionally, these long-held perceptions and stereotypes have influenced earlier archaeological studies, making some researchers reluctant to interpret the objects buried with women as hunting tools. In 2017, a burial in Sweden revealed an individual alongside weapons and equipment associated with high-ranking warriors, so the individual was assumed to be male. A genomic analysis confirmed that the individual was female. 

The team calls for older archaeological evidence to be reevaluated and caution against misapplying the idea that men are hunters and women are gatherers in future work. The findings also highlight the importance of flexibility in evolution.

“People are very good at being flexible,” says Wall-Scheffler. “Being locked into a specific role with no other options is probably not how we have been so successful as a species.”

The post Women have been skillful, purposeful hunters in most foraging societies appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

While humans and dinosaurs only co-existed in cartoons like The Flintstones, some of our very early ancestors potentially shared a brief moment with the likes of the Titanosaurs and the iconic Triceratops. These distant relatives also survived the catastrophic extinction event that was triggered by the asteroid that hit the Earth and wiped out non-avian dinosaurs, according to a study published June 27 in the journal Current Biology.

[Related: The fiery end of the dinosaurs kicked off the golden age of mammals.]

The study revealed that a Cretaceous origin for placental mammals, the diverse group that includes humans, dogs, and bats, briefly co-existed with dinosaurs before the dinosaurs went extinct. Placental mammals all bear live young that are nourished via an organ called the placenta in-utero.

On a spring day 66 million years ago, an asteroid struck the Earth near Mexico’s Yucatán Peninsula. The devastation in its wake wiped out all of the non-avian dinosaurs and many mammals, such as a rodent-looking animal named Vintana sertichi  that weighed up to 20 pounds and lived on Madagascar. Scientists have long debated if placental mammals were present with the dinosaurs before the Cretaceous-Paleogene (K-Pg) mass extinction, or if they only evolved after the dinosaurs died out. 

According to the team, the fossilized remains of placental mammals have only been found in rocks that are younger than 66 million years old. But molecular data has suggested an older origin for placental mammals.  

In this new study, a team of paleobiologists used statistical analysis of the fossil record to determine if placental mammals originated before this mass extinction event. They collected fossil data from placental mammal groups all the way back to 66 million years ago.

“We pulled together thousands of fossils of placental mammals and were able to see the patterns of origination and extinction of the different groups. Based on this, we could estimate when placental mammals evolved,” study co-author and University of Bristol paleobiologist Emily Carlisle said in a statement.

Their model estimates the origin of the ages based on when these mammal lineages first appear, and estimates extinction ages based on when the group goes extinct, according to the authors. 

[Related: Mammals’ ears may hold the secret to warm-bloodedness.]

They showed that the groups that include primates, rabbits and hares (Lagomorpha), and dogs and cats (Carnivora) evolved just before the K-Pg mass extinction. This means their ancestors were mingling with dinosaurs.  It was really only after the asteroid impact that the modern lines of today’s placental mammals started to take shape. As with other mammals, they likely began to diversify once the dinosaurs were out of the picture.

These early mammals certainly did thrive. A group of cat-sized mammals called condylarths, which includes the ancestors of today’s hooved animals, lived roughly within the first 328,000 years after the dinosaurs disappeared. Mammals also began to grow significantly since they had less competition for resources. One of the biggest winners among these mammals were Brontotheres or “thunder beasts,” which grew from 40 pound animals roughly the size of coyotes to 2,000 pound goliaths.  

The post The ancestor of all placental mammals survived the dino-killing asteroid appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

With their distinctive red fur and long, powerful arms, orangutans are hard to miss. It also might be hard to miss the sounds they make as they swing through the rainforests of Indonesia and Malaysia. A study published June 27 in the journal PNAS Nexus finds the primates can make two separate sounds simultaneously, just like songbirds or human beatboxers.

[Related: Why do humans talk? Tree-dwelling orangutans might hold the answer.]

According to the study team, these findings provide a window into the evolution of human speech and human beatboxing as well. The team observed two populations of vocalizing orangutans in Borneo and Sumatra in southeast Asia for about 3,800 hours. They saw that orangutans within both groups used the same “two sounds at the same time” vocal phenomenon.

“Humans use the lips, tongue, and jaw to make the unvoiced sounds of consonants, while activating the vocal folds in the larynx with exhaled air to make the voiced, open sounds of vowels,” study co-author and University of Warwick psychologist Adriano Lameira said in a statement. “Orangutans are also capable of producing both types of sounds—and both at once.

Borneo’s large male orangutans can produce noises known as “chomps” together with “grumbles” when being combative. Comparatively, the female orangutans in Sumatra make “kiss squeaks” with “rolling calls” to let others know about a potential threat from a predator. 

“The fact that two separate populations of orangutans were observed making two calls simultaneously, is proof that this is a biological phenomenon,” said Lameira.

[Related: Watch people beatbox in an MRI.]

For us humans, it’s rare that we produce voiced and voiceless noises at the same time, with beatboxing being a notable exception. The vocal performance mimics the complex beats of hip hop and is a staple on the a capella circuit. According to Guinness World Records, the longest beatbox marathon in history was an astonishing 25 hours and 30 minutes. It uses the mouth, tongue, lips, and vocal cords and may even be easier on the voice than traditional singing. 

“The very fact that humans are anatomically able to beatbox, raises questions about where that ability came from. We know now the answer could lie within the evolution of our ancestors,” study co-author and independent researcher Madeleine Hardus said in a statement. 

The team says that the vocal control and coordination abilities of wild great apes have been underestimated in the past when compared to the focus on birds’ vocals.

“Producing two sounds, exactly how birds produce song, resembles spoken language but bird anatomy has no similarity to our own so it is difficult to make links between birdsong, and spoken human language,” said Hardus.

The team believes that it is possible early human language did sound more like beatboxing, before it evolved into our current consonant and vowel language structure. 

 “Now that we know this vocal ability is part of the great ape repertoire, we can’t ignore the evolutionary links,” said Lameira.

The post Orangutans can make two sounds at the same time appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Most fish are cold-blooded, which means that they rely on the temperature outside of their body to regulate their internal temperatures However, some sharks are surprisingly warm-blooded, storing the heat that is generated by their muscles the way many mammals do. A study published June 26 in the journal Proceedings of the National Academy of Sciences finds that their evolutionary ancestors—the mighty megalodon—also share this endothermic nature. The amount of energy that the meg used to stay warm may have contributed to its extinction roughly 3.6 million years ago, and could help scientists study the impacts of future environmental changes.

[Related: 3D models show the megalodon was faster, fiercer than we ever thought.]

“Studying the driving factors behind the extinction of a highly successful predatory shark like megalodon can provide insight into the vulnerability of large marine predators in modern ocean ecosystems experiencing the effects of ongoing climate change,” co-author and UCLA biologist Robert Eagle said in a statement.

The megalodon stalked the world’s oceans from about 20 million years ago, and likely measured up to 50 feet in length. That’s roughly three times larger than the modern great white shark. The marine giants could have eaten a meal the size of an orca whale in about five bites, and boasted impressive chompers that could grow to the size of a human hand. 

They also belonged to a group of sharks called mackerel sharks, which includes present day thresher sharks and the infamous great white. Mackerel sharks keep the temperature of all or parts of their bodies a bit warmer than the water surrounding them, unlike most fish that are cold-blooded and keep their bodies the same temperature as the water.  

In the new study, a team analyzed the isotopes in the tooth enamel from fossilized megalodon teeth and concluded the ancient shark could maintain a body temperature that was roughly 13 degrees Fahrenheit warmer than the water it lived in. That temperature difference is large enough to categorize the megalodon as endothermic, or warm-blooded, according to the team.

They used a novel geochemical technique that uses a clumped isotope thermometry and phosphate oxygen isotope thermometry to test their “Megalodon Endothermy Hypothesis.”

“Studies using these methods have shown them to be particularly useful in inferring the thermo-physiologies of fossil vertebrates of ‘unknown’ metabolic origins by comparing their body temperature with that of co-occurring fossils of ‘known’ metabolisms,” co-author and William Patterson University geochemist Michael Griffiths said in a statement.

[Related: This whale fossil could reveal evidence of a 15-million-year-old megalodon attack.]

While the megalodon has a rich fossil record, its biology is less understood since no complete skeleton of the extinct beast is known in the fossil record. Using geochemistry techniques on the numerous teeth left behind can help paleontologists peer into the past. 

A mineral called apatite is a primary component of teeth. It contains atoms of both carbon and oxygen that come in “light” or “heavy” forms known as isotopes. The amount of light or heavy isotopes that make up apatite as it forms can vary based on multiple environmental factors. The isotopes that make up fossil teeth can then reveal insights into where the animals lived, what it ate, and for marine vertebrates like the megalodon, some hints on the chemistry of the seawater that it lived in and its body temperature. 

“You can think of the isotopes preserved in the minerals that make up teeth as a kind of thermometer, but one whose reading can be preserved for millions of years,” co-author and UCLA doctoral student Randy Flores said in a statement. “Because teeth form in the tissue of an animal when it’s alive, we can measure the isotopic composition of fossil teeth in order to estimate the temperature at which they formed and that tells us the approximate body temperature of the animal in life.”

The megalodon’s warmer body allowed it to move faster and not only tolerate colder water, but spread all over the world’ oceans. However, this evolutionary advantage may have contributed to its downfall. The megalodon lived during the Pliocene Epoch (5.33 million years to 2.58 million years ago), which was known for some massive environmental changes as the world cooled and sea levels changed. 

Sustaining and maintaining an energy level that allowed for the megalodon’s higher body temperature would have required quite a bit of food. As the ecosystem changes, food may have become more scarce, especially when factoring in competition with newcomers in the marine environment–like our friend the great white. 

The team hopes to apply a similar approach to studying other extinct species. “Having established endothermy in megalodon,” co-author and UCLA geologist Aradhna Tripati said in a statement, “the question arises of how frequently it is found in apex marine predators throughout geologic history.”

The post Megalodons were likely warm-blooded, despite being stone-cold killers appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

With their soft and spongy tissue, internal organs are rare in the fossil record. But the paleontologists who unearthed the remains of a 50 million year-old katydid hit a bit of a fossil jackpot. Parts of the digestive tract, muscles, glands, and even the testes of an extinct species of this lean-legged insect were preserved along with the bugs’ harder structures. The findings were described in a study published June 23 in the journal Palaeoentomology.

[Related: Bite marks on Triassic fossils show signs of bloody dino decapitation.]

“Katydids are very rare in the fossil record, so any new katydid fossil you find represents a new data point in the evolutionary history of katydids,” study co-author and University of Illinois Urbana-Champaign palaeoentomologist lead Sam Heads said in a statement. “But perhaps the most striking feature of this fossil is the really exceptional, remarkable preservation of internal organs – organs that you just don’t see in fossils.”

The specimen was found in Colorado’s Green River Formation. This enormous fossil bed extends into three western states and boasts fine-grained shales that preserve a good retail of the flora and fauna that once lived there. This new katydid species is extinct and is named 

Arethaea solterae in honor of Heads’ colleague and retired insect pathologist Leellen Solter.

“Obviously, having a fossil species of a modern genus is really significant because it confirms the antiquity of this lineage,” Heads said. “Now we know that about 50 million years ago, this genus had already evolved and already had a morphology that mimics the grass in which it lives and hides from predators.”

This rare look inside an extinct insect’s body will help scientists better understand how this group of insects evolved and when their unique physical structure developed over time.

A part of the digestive tract called the ventriculus—where two sets of muscles grind food—was preserved, which is not super unusual, according to Heads. However, when he examined the specimen underneath a microscope, he saw evidence of some surprising internal structures that had been preserved for millennia. Traces of the fibers making up the katydid’s thoracic muscle that are associated with wings were in the specimen, in addition to some tissue called a “fat body,” an organ that helps the insect’s metabolism. 

[Related: Fossil trove in Wales is a 462-million-year-old world of wee sea creatures.]

Yet another surprise awaited Heads. “There are these little tubules that all seem to connect to a round structure – and that can only be a testis and accessory glands that are associated with the testis,” Heads said. “That’s just phenomenal. I was not expecting to see that kind of structure preserved in a rock compression. I’ve never seen that before.”

Just to make sure, Heads dissected several katydid specimens in this same genus to match what he was seeing in this 50 million year-old fossil. The accessory glands and ventriculus were the same in the modern day katydids and looked exactly the same. It is potentially the first example of this level of preservation.

The post A 50-million-year-old insect testicle is one lucky find appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

From the doomed real-life crewmembers of the Nineteenth Century whaleship Essex to the fictional yet grisly soccer-player on soccer-player crime in season 2 of the hit-series Yellowjackets, cannibalism grips our minds in both fiction and the real world.

[Related: Dinosaur cannibalism was real, and Colorado paleontologists have the bones to prove it.]

In a study published June 26 in the journal Scientific Reports, a team of researchers from the Smithsonian describe what could be the oldest decisive evidence of our close evolutionary relatives butchering—and likely eating—one another.

The team examined a 1.45-million-year-old left shin bone from an unknown Homo sapien relative that was found in northern Kenya. The bone has nine cut marks, and analysis of 3D models of the fossil showed that they are very close to the damage that is inflicted by stone tools. According to the team, this is the oldest instance of this behavior known with a high degree of confidence and specificity.

“The information we have tells us that hominins were likely eating other hominins at least 1.45 million years ago,” study co-author and National Museum of Natural History paleoanthropologist Briana Pobiner said in a statement.  “There are numerous other examples of species from the human evolutionary tree consuming each other for nutrition, but this fossil suggests that our species’ relatives were eating each other to survive further into the past than we recognized.”

The fossilized tibia was housed in the National Museums of Kenya’s Nairobi National Museum collections. Pobiner encountered them while searching for clues on which prehistoric predators could have hunted and eaten our ancient relatives and she noticed the evidence of butchery while checking the bone for bite marks.

Pobiner sent molds of these cuts to co-author Michael Pante of Colorado State University to try to figure out if these were actually cut marks. Pante created 3D scans of the molds and then compared the shape of the marks with a database of 898 individual tooth, butchery, and trample marks that were created through controlled experiments.

According to the analysis, nine of the 11 total marks were positively identified as clear matches for the type of damage inflicted by stone tools. The remaining two marks were likely a big cat’s bite marks, with a lion being the closest match. The bite marks also could have come from one of the three different types of saber-tooth cats that prowled the landscape at this time. 

The cut marks alone do nor prove that whomever butchered the owner of this leg made a meal out of them, but Pobiner believes that this seems to be the most likely scenario. The markings are located where the calf muscle would have attached to the bone, which is a good place to cut if the assailant’s goal was to remove a chunk of flesh. Additionally, the cut marks are all oriented the same way, suggesting that a hand wielding a stone tool may have made the marks in succession without changing their grip or adjusting the angle. 

[Related: Lucy, our ancient human ancestor, was super buff.]

“These cut marks look very similar to what I’ve seen on animal fossils that were being processed for consumption,” Pobiner said. “It seems most likely that the meat from this leg was eaten and that it was eaten for nutrition as opposed to for a ritual.”

On the surface, it looks like this could be an example of prehistoric cannibalism, but cannibalism requires the eater and the eaten to be of the same species. Initially, the shin bone was identified as Australopithecus boisei and then as Homo erectus in 1990. Today, experts agree that there is not enough conclusive information to know what species of hominin the bone belongs to. The use of stone tools also doesn’t narrow down which species might have been the butcher. 

This fossil could be a trace of prehistoric cannibalism, but also may have been a case of one species making a meal out of its evolutionary cousin.

Since none of the stone-tool cut markings overlap with two bite marks, it makes it even harder for scientists to infer anything about the order of events that took place when this hominin lost its leg. It’s possible that a big cat may have scavenged the remains after other hominins removed most of the meat from the leg bone, or that a big cat killed this unlucky prehistoric human and was chased off by other hominins that wanted to take over the kill. 

[Related: 2.9 million-year-old tools found in Kenya stir up a ‘fascinating whodunnit.’]

A fossilized skull first discovered in South Africa in 1976 previously sparked debate about the earliest known case of human relatives butchering each other. This skull was roughly 1.5 to 2.6 million years old. Studies on the skull from 2000 and 2018 disagreed about the origin of the marks left on the skull’s right cheek bone. One proposes that the marks were the result from stone tools used by hominid relatives, while the other study asserts that the marks were formed through contact with sharp-edged stone blocks that were found lying against the skull. If ancient hominins actually did use tools to put marks on the skill, it still isn’t clear if they were butchering each other for food, due to a lack of large muscle groups on the skull.

In future tests to determine once and for all that the fossilized tibia in this new study is actually the oldest cut-marked hominin fossil, Pobiner said she would love to reexamine the skull from South Africa, since it potentially has cut marks that were made using similar techniques observed in her new study. 

The findings are also another example of the treasures that could be lurking in museum drawers and cupboards around the world just waiting to be uncovered. 

“You can make some pretty amazing discoveries by going back into museum collections and taking a second look at fossils,” Pobiner said. “Not everyone sees everything the first time around. It takes a community of scientists coming in with different questions and techniques to keep expanding our knowledge of the world.”

The post Cut-up prehistoric bone raises questions about early human cannibalism appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

A new species of early odontocete—or toothed whale—is giving us a closer look into what some of the earliest ancestors of present-day dolphins may have looked like. In a study published June 23 in the journal PeerJ Life and Environment, paleontologists describe a new species called Olympicetus thalassodon that is helping scientists understand the early history and eventual diversification of odontocetes.

[Related: Toothed whales turned their vocal fry into a hunting superpower.]

Toothed whales include porpoises, dolphins, sperm whales, orca whales, and, as their name would suggest, they all have some kind of teeth within their jaws. Unlike baleen whales (humpbacks, North Atlantic right whales, etc.) that use their baleen, a filtering system in their mouths primarily made out of bristly keratin plates, to filter feed large amounts of food, odontocetes typically only feed on one fish, squid, or other invertebrates at a time. They are also highly social and most, if not all, toothed whales use echolocation to find their way around the ocean and locate their next meal. 

Odontocetes first evolved during the Oligocene Epoch (about 33.7 million to 23.8 million years ago) and the fossils of Olympicetus thalassodon were found in a geologic formation in the Northwest US that dates back to between 26.5–30.5 million years. 

“Olympicetus thalassodon and its close relatives show a combination of features that truly sets them apart from any other group of toothed whales. Some of these characteristics, like the multi-cusped teeth, symmetric skulls, and forward position of the nostrils makes them look more like an intermediate between archaic whales and the dolphins we are more familiar with,” study co-author and paleontologist from the Natural History Museum of Los Angeles County Jorge Velez-Juarbe said in a statement. 

Olympicetus thalassodon was not alone in the water, and paleontologists found the remains of two other closely related odontocetes nearby and the specimens described in the same study. The specimens were unearthed in the Pysht Formation, an exposed layer of rock along the coast of Washington State’s rugged Olympic Peninsula.

The study found that Olympicetus and its close kin belonged to a family called Simocetidae. This group is only known to have swam in the waters of the North Pacific, and is one of the earliest diverging groups of toothed whales on the whale family tree. Simocetids were part of an unusual group of animals represented by fossils found in the Pysht Formation. Some of these strange Pysht fauna include an extinct group of penguin-like flightless birds called plotopterids, early seal and walrus relatives called desmostylians, and even extinct toothed baleen whales.

[Related: Millions of years ago, marine reptiles may have used Nevada as a birthing ground.]

Based on differences in body size, teeth, and other body structures related to feeding, simocetids may have acquired prey differently and had varying prey preferences. 

“The teeth of Olympicetus are truly weird, they are what we refer to as heterodont, meaning that they show differences along the toothrow,” said Velez-Juarbe. “This stands out against the teeth of more advanced odontocetes whose teeth are simpler and tend to look nearly the same.”

However, some additional aspects of their biology has yet to be uncovered, including whether or not they could echolocate like their living relatives. Their skulls do indicate the potential presence of a melon, which is an important echolocation-related structure. Additionally, a 2019 study suggested that neonatal whales found in the Pysht Formation couldn’t hear ultrasonic sounds, and future study into the ear bones of subadult and adult individuals could test if this ability changed as they aged.  

The post This dolphin ancestor looked like a cross between Flipper and Moby Dick appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Cave paintings and markings uncovered by anthropologists and archaeologists can be categorized as art—some may even count as early forms of writing. Despite finding drawings in caves across Europe and as far as Indonesia from thousands of years ago, relatively little is still known about the artistic expressions made by both primitive Homo sapiens and extinct Neanderthals.

[Related: How Neanderthal genetic material could influence nose shapes to this day.]

According to a study published June 21 in the open-access journal PLOS ONE, some markings on a cave wall in France date back more than 57,000 years ago, making them the oldest known engravings made by Neanderthals to date. 

“Fifteen years after the resumption of excavations at the La Roche-Cotard site, the engravings have been dated to over 57,000 years ago and, thanks to stratigraphy, probably to around 75,000 years ago, making this the oldest decorated cave in France, if not Europe!” the authors wrote in a statement. 

Neanderthals are slowly shaking their reputation as our more “primitive” cousins. A 2021 find from a “Unicorn Cave” in Germany found early hints of Neanderthal art dating back 51,000 years. Neanderthals also could have lived in tight family bonds and possibly even cooked crab 90,000 years ago. 

Only a few artistic productions like the ones from Germany are attributed to Neanderthals, and their meaning is still subject to debate. The newly-found drawings, spotted in a cave called La Roche-Cotard in central France’s Loire Valley, could give scientists more insight. 

The team interprets this series of non-figurative markings on the wall as finger-flutings– or marks made by human hands. They made a plotting analysis and used photogrammetry to build 3D models of the markings and compared them with known and experimental human markings. Based on the arrangement, spacing, and shape of the engravings, the team believes that they are deliberate, intentional, and organized shapes that human hands created. 

The sediments within the cave were dated using a process called optically-stimulated luminescence dating. According to the researchers, this particular cave was closed up by sediment about 57,000 years ago—roughly 3,000 years before Homo sapiens became established in Europe. 

The age of the sediments, combined with the fact that stone tools in the cave are associated with a Neanderthal-specific technology called Mousterian, is strong evidence that these engravings are the work of Neanderthals, according to the team.

[Related: Sex, not violence, could’ve sealed the fate of the Neanderthals.]

These nonfigurative, and still indecipherable, creations are a similar age with cave engravings that Homo sapiens made in other parts of the world, adding more evidence to the idea that Neanderthals were as complex and diverse as our own human ancestors. 

The post Neanderthals were likely creating art 57,000 years ago appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

While both humans and horses can sport shoes, our equine friends don’t need to worry about maintaining their toes. However, that was not always the case. A new literature review published on June 21 in the journal Royal Society Open Science demonstrates how the distant ancestors of modern horses actually had multiple hoofed toes. Over time, these toes vanished—leaving the singular hoof. 

[Related: A centuries-old horse tooth holds clues to the mystery of the Chincoteague ponies.]

The earliest horse ancestors started popping up in the fossil record around 56 million years ago. Most early horses sported three full-sized toes touching the ground, with the Eocene era’s Hyracotherium boasting four front toes like the modern tapir. While their three toes touched the ground, the middle toe did most of the heavy lifting, with the side toes dangling off the ground, unless it was time to jump or quickly run. 

Present-day equids, including horses, donkeys, and zebras, have only a single toe. The leftover original middle toe on each foot is encased within a thick-walled keratinous hoof. To help absorb shock as the horse walks, trots, or gallops, a triangular and highly elastic hoof-part called a frog sits on the sole of the hoof.

An international team of scientists from institutions in the United Kingdom, the United States, and the Netherlands analyzed hoof prints and foot bones from modern horses and fossil records to look closer at what happened to the lost digits over time. 

“The upper portions—the remains of the additional hand and foot bones—remain as ‘splint bones’ fused with the remaining central one, but where are the fingers and toes?” study co-author and University of Bristol paleontologist Christine Janis said in a statement.  “In later fossil horses there were only three toes front and back. The extra toes, known as side toes, in these horses were smaller and shorter than in a tapir, and likely did not touch the ground under normal circumstances, but they may have provided support in exceptional situations, such as sliding or forceful impact.”

The team’s findings confirm an older notion that these toes truly have been lost as the animals evolved, and are not somehow retained within the hoof. This hoof-theory was proposed in a paper also published in Royal Society Open Science in 2018

“Although it does seem that remainders of the proximal (upper portions) of the side digits have been retained in modern horses, as the earlier 2018 paper claimed, the distal (lower portions, or toes) have simply been lost,” study co-author and St. John’s Seminary biologist Alan Vincelette said in a statement. 

[Related: People may have been riding horses as early as 5,000 years ago.]

The 2018 paper proposed that the side toes in modern horses are retained within the hoof of the central toes, which partially contributes to the foot’s frog. This theory was partially based on an interpretation of hoof prints from an extinct three-toed horse, Hipparion. This equine is on the direct line to modern horses and the roughly 3.7 million year old fossil was found in Laetoli, Tanzania. This same fossil site is home to the famous footprints of the hominid Australopithecus. 

Hipparion’s hoof prints apparently lacked a frog on the hoof, which added weight to the idea that the side toes of older horses now contribute to the stretchy frog of modern horses. Not all hoof prints from modern horses with frogs show its presence, meanwhile the frog can be seen in many hoof prints known to have been made by three-toed horses. 

“While the notion that modern horses have retained all of their original toes as within-hoof remnants is a novel one, and so rather appealing, it can be shown to be incorrect,” said Janis.

The team believes that the frog of the horse’s hoof evolved independently of the side toes. This unique structure provides the animal with both traction and shock absorption during movement.  

Additionally, the feet of one-toed horses have a different shape from the main toe than those of three-toed horses: this powerful toe is round instead of oval-shaped. This difference in shape is possibly related to differences in ecological habitat, or possibly weight distribution.

The post Horses once had multiple hoofed toes appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Living at the extremes of the Triassic era would’ve been pretty rough. It started and finished with massive extinction events, picking up from the end of the single-continent Permian period around 250 million years ago, and giving way to the Jurassic period 50 million years later. The creatures of the Triassic era were a diverse combination of apocalypse survivors, short-lived wonders, and the earliest forms of dinosaurs called the archosaurs. 

One such archosaur was the genus of the Tanystropheus—ancient water-dwelling reptiles with wildly long and skinny necks. First discovered in Germany over 170 years ago, the largest specimens of Tanystropheus had a neck that stretched nearly 10 feet. These strange beasts used their tiny skulls and extensive, inflexible necks to prowl the seas for snacks—some larger species fed on fish and squid while smaller species trawled for soft-shelled animals. Considering such an appendage would probably make for a nightmarish hassle on land, scientists think these creatures spent most of their time wading or swimming in water. 

But new research shows that, perhaps unsurprisingly, these lengthy necks were also gigantic liabilities.

“Paleontologists speculated that these long necks formed an obvious weak spot for predation, as was already vividly depicted almost 200 years ago in a famous painting by Henry de la Beche from 1830,” Stephan Spiekman of the Staatliches Museum für Naturkunde in Stuttgart, Germany said in a release. That painting shows a crocodile-like swimmer chomping on the neck of another dino. “Nevertheless, there was no evidence of decapitation—or any other sort of attack targeting the neck—known from the abundant fossil record of long-necked marine reptiles until our present study on these two specimens of Tanystropheus.”

According to research published by Spiekman and others in the journal Current Biology on June 19, Triassic predators sure knew how to decapitate multiple species of Tanystropheus. Looking closely at two fossils from two distinct species of the aquatic reptile, scientists found clear evidence of snapped necks—including, on one specimen, bite marks right at the snapping point. The skulls and necks of these specimens look more or less well preserved and undisturbed, but the rest of their bodies are nowhere to be found. 

“The fact that the head and neck are so undisturbed suggests that when they reached the place of their final burial, the bones were still covered by soft tissues like muscle and skin,” Eudald Mujal, another study author also from the Stuttgart Museum, said in the release. The predator hadn’t eaten the dinosaur’s face, which Mujal speculates was because the skinny neck and small head wouldn’t have made a meaty meal, unlike other parts of the body. “Taken together, these factors make it most likely that both individuals were decapitated during the hunt and not scavenged,” he added, “although scavenging can never be fully excluded in fossils that are this old.” 

This research just shows how weird evolution can be—after all, long-necked marine reptiles have been successful on Earth for millions of years. Tanystropheus themselves lasted at least 10 million years during an incredibly tumultuous time to be existing on the planet (for reference, the genus Homo has only been around for approximately 3 million years). “In a very broad sense, our research once again shows that evolution is a game of trade-offs,” Spiekman added.

The post Bite marks on Triassic fossils show signs of bloody dino decapitation appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

There are some places in the world that are just magnets for dinosaurs—Utah’s Cedar Mountain Formation, the fossil beds of Liaoning, China, Alberta’s Dinosaur Provincial Park. In the UK, one such hot spot is the Isle of Wight, a 148 square mile island now known as a popular summer holiday spot. Nevertheless, the tiny island is home to numerous dinosaur discoveries, including Europe’s largest prehistoric predator and a tyrannosaurid that lived 60 million years before the iconic Tyrannosaurus rex.  

[Related: Celebrate 30 years of Jurassic Park with these recent dinosaur discoveries.]

However, there’s always something new to discover, even on an island just slightly larger than the city of Atlanta. This time, scientists have uncovered the island’s second armored dinosaur in the Wessex formation which dates back to the earliest years of the Cretaceous. The newly named Vectipelta barretti was described in a study published in the Journal of Systematic Palaeontology on June 15. 

The finding, which utilized fossils that were first uncovered in the 1980s, is particularly important because it reopens the book on the development of ankylosaur dinosaurs in the region. Previously, only one ankylosaur, the Polacanthus foxii, had been found on the entire island. The Polacanthus foxii was first discovered in 1865, and up until now, the Vectipelta barretti had just been lumped in with those fossils. 

“For virtually 142 years, all ankylosaur remains from the Isle of Wight have been assigned to Polacanthus foxii, a famous dinosaur from the island,” Stuart Pond, a researcher at London’s National History Museum department of earth sciences and lead author of the study, said in a statement. “Now all of those finds need to be revisited because we’ve described this new species.” 

The newly described dinosaur has a very different pelvis and distinct neck and back vertebrae compared to the Polacanthus. Additionally, it features unique blade-like and recurved spikes along its back, Susie Maidment, a dinosaur researcher at the National History Museum, said in a statement. In fact, the differences, as well as phylogenetic analysis, lead the authors to believe that the Vectipelta’s closest kin may have hailed all the way from China. 

“And when we put Vectipelta into a big evolutionary analysis to work out the relationship of all these different dinosaurs, we find that Polacanthus and Vectipelta are not actually very closely related,” Maidment said. “They are really quite far apart in terms of ankylosaur evolution, so it is really very clear that this is a different species.”

[Related: Feisty ankylosaurs clubbed each other with their tails.]

During the Early Cretaceus (about 145 to 100 million years ago) when the Vectipelta would’ve roamed free, the continent of Pangea was rifting apart and the climate was much warmer worldwide.  Europe at this point was a series of islands, one of which including today’s southern England and the Isle of Wight. There was little or no ice at either of the poles, and sea levels were around 557 feet higher than they are today. 

While Ankylosaurs were typically plant eaters, similarly to the much beloved Jurassic-era Stegosaurus, they still certainly weren’t to be messed with—those bony, spiky plates were built to fend off carnivorous predators.

The post This extremely metal Cretaceous dinosaur grew blade-like armor appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Around 1,500 of the living lizard species on Earth fall into the skink family—a category of small reptiles noted for their unusually short legs and lack of a distinct neck. These chunky little creatures are found pretty much everywhere—the islands of Southeast Asia, deserts of Australia, and temperate zones of North America. But what we know of the paleontological history of these reptiles is limited. While we have a good idea about many prehistoric giant birds and mammals, the early days of the skink are still shrouded in mystery.

Perhaps unsurprisingly, the biggest skink known to history was recently discovered where lots of other giant creatures once roamed—Australia. About a decade ago, scientists uncovered an unusually large lizard-like skull and jaw in the Wellington caves in New South Wales. A new analysis published in Proceedings of the Royal Society B on June 13 unveiled that those two bones, as well as finds from a more recent excavation in the region, belong to an extinct skink species called the Tiliqua frangens.

[Related: The biggest animal ever to fly was a reptile with a giraffe-like neck.]

The new species, lovingly nicknamed by its discoverers as “Mega Chonk” and “Chonkasaurus,” is considerably larger than today’s skink specimens. The average skink comes in at around 4 inches long, weighing less than 0.07 ounces. This newly discovered fella was around 22 inches long, and weighed around 6 pounds—making it around 1,000 times bigger than its modern day counterparts. 

“We don’t often find new ‘giants’ in the fossil record, and lizard fossils are especially hard to piece together, so this was particularly exciting,” says Kailah Thorn, study author and paleontologist at the Western Australian Museum. It helps fill in what scientists know about extinct squamates—a group that includes geckos, pythons, and other reptiles with scales.

The fossils from this short-legged, strong-jawed creature were dated back around 47,000 years ago, when the largest-known kangaroos, massive flightless birds, and wombats weighing more than three tons roamed through the outback. Although Tiliqua was petite compared to these massive mammals, it filled an important role: seed dispersal, which was fulfilled on other continents via land tortoises. 

[Related: Snakes may not have legs, but they do have two penises.]

“Australia didn’t have terrestrial tortoises filling that body size and diet niche like they do in Africa and the Americas,” says Thorn. “Instead, we have a giant Shingleback!” she says, referring to the lizard’s spiky armored back. 

However, similar to their supersized neighbors, the lizards met an unfortunate extinction around 40,000 years ago. Luckily, there’s still a close living relative of the creature in Australia today with many of the same characteristics—only much shrimpier. 

The post This chunky ancient lizard was 1,000 times bigger than its modern relatives appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

If you see one of the thousands of billions of the planet’s ants on your kitchen counter, it’s never truly just one bug. That lone ant usually signals to an entire colony when there is both food and danger nearby. A study published June 14 in the journal Cell takes a closer look into how certain scent markers that the insects use to communicate with one another activate a specific part of the ant brain, which can then change the behavior of an entire nest. 

[Related: This spider pretends to be an ant, but not well enough to avoid being eaten.]

“Humans aren’t the only animals with complex societies and communication systems,” co-author and neurobiologist at The Rockefeller University Taylor Hart said in a statement. “Over the course of evolution, ants have evolved extremely complex olfactory systems compared to other insects, which allows them to communicate using many different types of pheromones that can mean different things.”

The study suggests that ants do have their own communication centers in their brains, just like humans do. They can interpret the danger-signaling pheromones secreted by other ants—and their olfactory clues are potentially more advanced than that of other insects like honeybees. Earlier studies have suggested that bees rely on multiple parts of their brain to coordinate in response to one single pheromone. 

“There seems to be a sensory hub in the ant brain that all the panic-inducing alarm pheromones feed into,” co-author and evolutionary biologist at The Rockefeller University Daniel Kronauer said in a statement.

In this study, the team looked at clonal raider ants. They used an engineered protein called GCaMP to scan the brain activity of ants that were exposed to danger signals. GCaMP attaches itself to calcium ions, which then flares up with brain activity. A fluorescent chemical compound is then visible on high-resolution microscopes that are adapted to view them.

On these scans, the team saw that only a small part of the ants’ brains lit up in response to danger signals. However, the ants still showed instant and complex behaviors. They named these behaviors the panic response, since the ants evacuated the nest, fled, or transported their offspring away from the nest. 

Species of ants that have different colony sizes also use other pheromones to send a variety of messages. 

“We think that in the wild, clonal raider ants usually have a colony size of just tens to hundreds of individuals, which is pretty small as far as ant colonies go,” said Hart. “Frequently, these small colonies tend to have panic responses as their alarm behavior because their main goal is to get away and survive. They can’t risk a lot of individuals. Army ants, the cousins of the clonal raider ants, have massive colonies—hundreds of thousands or millions of individuals—and they can be much more aggressive.”

[Related: The protein that keeps worker ants in line can also make them queen.]

Ants within a colony meticulously organize themselves by role and caste, and the ants within different castes and roles in the colony also have slight variations in their anatomy. The researchers used clonal raider ants of one sex within one caste and role to ensure consistency. Observing only female worker ants made it easier to observe widespread patterns.

As the team gains a clearer understanding of the neural differences between ant roles, sexes, and castes, which could help them decipher how different ant brains process the same danger signals.

The post Ants brains are surprisingly good at communicating danger to others appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

In late November 1974, the world of archeology changed when scientists discovered Lucy (a nod to a famous Beatles track played over and over at the dig site), a 40-percent complete fossil of a young female Australopithecus afarensis in Ethiopia. This species of ancient hominid was living and walking around on two feet in East Africa 3.7 to 3 million years ago, long before the earliest stone tools were made. While Lucy and her relatives were shorter, more ape-like, and had smaller brains than Homo sapiens, they showed just how long human-like creatures were evolving and strolling about on Earth.

Just recently, scientists uncovered that Lucy, whose remains are housed in a specially constructed safe in the National Museum of Ethiopia, may have been even more like us than we thought—and considerably more muscular in the legs department. According to a new paper published on June 13 in the journal Royal Society Open Science, Lucy could walk around upright just as well as a person.

[Related: The ‘granddaddy’ of all early hominins walked on Earth a lot longer than we thought.]

Previously, paleoanthropologists disagreed on Lucy’s bipedal stance. Some thought she likely waddled around with her back hunched over, not unlike today’s chimpanzees. However, Ashleigh Wiseman, a paleoanthropology research associate at the University of Cambridge, created 3D models of the leg and pelvis muscles of the 3.2 million-year-old Australopithecus afarensis. After recreating 36 muscles in each of the ancient hominids’ legs, she found that Lucy’s stance was quite similar to humans. 

Not only could she walk like a Homo sapien, but she was considerably more muscular than us—her calves and thighs were more than twice the size of those of modern humans. Her thighs in particular were made up of 74 percent muscle, compared to the average 50 percent split between fat and muscle in our species today. 

This shouldn’t be too surprising, however, given the world ancient hominids lived in. To manage life in East Africa 3 million years ago, Lucy and her cousins would’ve had to roam wooded grasslands, while swiftly switching to climbing forest canopies, Wiseman said in a statement. 

“We are now the only animal that can stand upright with straight knees. Lucy’s muscles suggest that she was as proficient at bipedalism as we are, while possibly also being at home in the trees,” Wiseman added. “Lucy likely walked and moved in a way that we do not see in any living species today.”

[Related: 2.9 million-year-old tools found in Kenya stir up a ‘fascinating whodunnit’.]

3D models have previously been used to reconstruct the muscles of other lost species. In fact, Wiseman mentions that the method has helped paleontologists figure out the shockingly slow running speeds of T. rexes. But recreating the builds of our ancestors lets us see how far we’ve come—and how much muscle we’ve lost as our lifestyles have shifted. 

“Of course, in the fossil record we are left looking at the bare bones,” Wiseman told CNN. “But muscles animate the body—they allow you to walk, run, jump and even dance. So, if we want to understand how our ancestors moved, we first need to reconstruct their soft tissues.”

The post Lucy, our ancient human ancestor, was super buff appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

What we experience each day makes an impact on us, good or bad. After all, starting your morning with a smile from a loved one will brighten your mood quite a bit more than driving past roadkill on your a.m. commute. But, depending on how drastic the circumstances, witnessing something can have effects that last much longer than  the afternoon. 

For years, scientists have wondered and studied how exposure to certain things, such as childhood trauma or stress, impacts the way that we age. In an ongoing set of experiments, they’ve had fruit flies sub in for humans. As it turns out, when tiny insects see or smell something tragic, that has an impact on how quickly the invertebrates age.

[Related: Horny male fruit flies plunge into chaos when exposed to air pollution.]

For a study published in 2019, a group of scientists from the University of Michigan discovered that when a fruit fly or Drosophila melanogaster was exposed to a dead fruit fly, this exposure induced cues that were unattractive to other flies, changed their brain chemistry, decreased their fat stores, reduced starvation resistance, and accelerated aging. These kinds of reactions aren’t exactly rare—the authors cite how certain social insects like ants will move dead bodies out of their living spaces. Elephants, too, vocalize and inspect corpses when in the presence of dead elephants, and when female baboons mourn their dead they experience increased stress hormones.

The team now understands a bit more about what’s going on in a fly’s tiny brain upon seeing their deceased brethren, and published these findings in PLOS Biology on June 13.  For this latest experiment, the team investigated neural circuits and central signaling processes in the brains of traumatized Drosophila. 

[Related: Flies evolved before dinosaurs—and survived an apocalyptic world after the Permian extinction.]

The researchers used fluorescent tagging to see what occurred in the brain, and when exposed to other dead flies, there was an increased activity in the ellipsoid body. This part of the brain harbors cells called laminated ring neuron axons, which supply the ellipsoid body with nerves, and mediates sensory integration and motor coordination. To see which ring neurons were associated with this response, the researchers silenced them one by one. This revealed two ring neuron axons that hold a specific receptor, which binds with the messenger molecule serotonin, were necessary for the response. Later, the researchers artificially activated these same neurons and found that fruit fly life spans shrunk when they were turned on, even if the insect hadn’t come in contact with a dead fly previously. 

In a world obsessed with aging—how to prevent it, how to slow it, or even stop it altogether—this kind of research can, according to the researchers, help develop drugs that pause the clock for humans. But until then, the takeaway here is that even for creatures that are only a tenth to a fifth of an inch in size, coming to terms with death is complicated.

The post Flies age faster once they’ve seen death appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Ancient organisms that bobbed through Earth’s waterways at least 1.6 billion years ago may not seem to have much in common with humans, but we couldn’t have evolved without eukaryotes called Protosterol Biota. A team of researchers have found a “lost world” of these ancient organisms inside a rock that had formed at the bottom of the ocean near Australia’s present day Northern Territory. The findings are described in a study published June 7 in the journal Nature.

[Related: Fossil trove in Wales is a 462-million-year-old world of wee sea creatures.]

Eukaryotes like Protosterol Biota have a complex cell structure that includes the mitochondria (known by many as the powerhouse of the cell) and a nucleus that acts as the cell’s control and information center. Modern eukaryotes on Earth include plants, fungi, animals and unicellular organisms like amoeba. All creatures whose cells house a nucleus can trace their lineage back more than 1.2 billion years ago to the Last Eukaryotic Common Ancestor (LECA). 

According to the researchers, Protosterol Biota may have been the first predators on Earth. They inhabited marine ecosystems around the world and likely played a large role in shaping the ecosystem. Protosterol Biota also lived at least one billion years before any animal or plant species emerged. 

“Molecular remains of the Protosterol Biota detected in 1.6-billion-year-old rocks appear to be the oldest remnants of our own lineage – they lived even before LECA. These ancient creatures were abundant in marine ecosystems across the world and probably shaped ecosystems for much of Earth’s history,” co-author and biogeochemist at the University of Bremen in Germany Benjamin Nettersheim said in a statement. “Modern forms of eukaryotes are so powerful and dominant today that researchers thought they should have conquered the ancient oceans on Earth more than a billion years ago.”

Fossilized remains of eukaryotes are very scarce, even though modern eukaryotes are very powerful and dominant today. Researchers believed they should have conquered ancient oceans more than a billion years ago, and evolutionary scientists have been trying to piece together a puzzle. Why didn’t our highly capable eukaryotic ancestors eventually dominate the world’s waterways, and where they were hiding?

“Our study flips this theory on its head. We show that the Protosterol Biota were hiding in plain sight and were in fact abundant in the world’s ancient oceans and lakes all along. Scientists just didn’t know how to look for them – until now,” said Nettersheim.

[Related: Scientists genetically engineered prehistoric proteins to detect diseases.]

Protosterol Biota thrived from about 1.6 billion years ago up until roughly 800 million years ago and were more complex than bacteria. They were also probably larger than bacteria, but scientists still don’t know what they looked like. They may have been Earth’s first predators, hunting down and munching on smaller bacteria.

The team studied fossil fat molecules that were found inside the rocks in Australia. The molecules had a primordial chemical structure that offered clues to the existence of early complex creatures that evolved before LECA and had since gone extinct.  

“Without these molecules, we would never have known that the Protosterol Biota existed. Early oceans largely appeared to be a bacterial world, but our new discovery shows that this probably wasn’t the case,” said Nettersheim.  

During a period called the Tonian Transformation, which took place about 1,000 to 720 million years ago, more advanced nucleated organisms including algae and fungi began to flourish. However, scientists still do now know exactly when the Protosterol Biota went extinct.

“The Tonian Transformation is one of the most profound ecological turning points in our planet’s history,” Jochen Brocks, a study co-author and geobiologist at Australia National University, said in a statement. “Just as the dinosaurs had to go extinct so that our mammal ancestors could become large and abundant, perhaps the Protosterol Biota had to disappear a billion years earlier to make space for modern eukaryotes.”  

The post Newfound single-celled hunters may have been Earth’s first-ever predators appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

On this fossil Friday, we’d like you to meet the rhynchosaur. This ancient reptile is a distant relative of crocodiles and modern birds, roaming through present day North and South America, Europe, Africa, Madagascar, and India between 250 to 225 million years ago. It belongs to a group of roughly sheep-sized ancient reptiles that thrived during the Triassic Period. The Triassic is known for its hot climate and abundance of vegetation.

[Related: This tiger-sized, saber-toothed, rhino-skinned predator thrived before the ‘Great Dying.’]

A study published June 8 in the journal Palaeontology describes a handful of rhynchosaur specimens  found in Devon in southwestern England. Researchers used CT scanning to see how their teeth wore down as the herbivores fed on leafy greens and other rough vegetation, as well as how new teeth were added towards the back tooth rows when the animals grew in size. As the vegetation took its toll on the rhynchosaur’s teeth, they likely starved to death as they aged.  

“Comparing the sequence of fossils through their lifetime, we could see that as the animals aged, the area of the jaws under wear at any time moved backwards relative to the front of the skull, bringing new teeth and new bone into wear,” co-author and University of Bristol paleobiology student Thitiwoot Sethapanichsakul said in a statement. “They were clearly eating really tough food such as ferns, that wore the teeth down to the bone of the jaw, meaning that they were basically chopping their meals by a mix of teeth and bone.”

During the Triassic, rhynchosaurs were an important part of Earth’s ecosystem. Life on Earth was recovering from the greatest mass extinction in the planet’s history. During the Permian-Triassic mass extinction, or the “Great Dying,” massive volcanic eruptions triggered catastrophic climate changes that killed 80 to 90 percent of species on Earth. It paved the way for dinosaurs to dominate Earth, but was even more dramatic than the extinction event that wiped out the dinosaurs 65 million years ago. 

Rhynchosaurs helped set the scene for new types of ecologies as dinosaurs became dominant, followed by the rise of the mammals. 

“I first studied the rhynchosaurs years ago and I was amazed to find that in many cases they dominated their ecosystems,” co-author and University of Bristol paleontologist Mike Benton said in a statement. “If you found one fossil, you found hundreds. They were the sheep or antelopes of their day, and yet they had specialized dental systems that were apparently adapted for dealing with masses of tough plant food.”

[Related: These tiny ‘dragons’ flew through the trees of Madagascar 200 million years ago.]

The team compared examples of earlier rhynchosaurs like the ones unearthed in Devon, with later-occurring samples from Argentina and Scotland. They were able to see how their teeth developed over time, and eventually how this unique dentistry allowed the species to diversify twice. Their chompers changed in the Middle and Late Triassic. 
Ultimately, another period of climate change and especially major changes in the kinds of plants available for the reptiles to eat, allowed the dinosaurs to take over and the rhynchosaurs went extinct just before the end of the Triassic period, roughly 237 to 227 million years ago.

The post This ancient reptile had a deadly vegetarian diet appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Octopuses can do it all, from their signature camouflage to chucking shells at other octopuses, but one major thing they can’t do is thermoregulate. Changes in water temperature can threaten their powerful brains due to this quirk of evolution, but they still manage to handle it.

[Related: Pygmy zebra octopus stripe patterns are as unique as human fingerprints.]

A study published June 8 in the journal Cell shows that two-spot octopuses adapt to seasonal shifts in temperature by producing different neural proteins. They accomplish this by editing their RNA—the messenger molecule between proteins and DNA. The team on this study believes that this rewiring protects their brains and this strategy is likely used across other octopuses and squid. 

“Ten years ago, there were some hints that something unusual was going on, but there wasn’t [any] systematic mapping and our first goal was to systematically map the editing sites of the squid,” study co-author and a statistical mathematician at Tel Aviv University Eli Eisenberg tells PopSci. 

They found that squid have tens of thousands of recording sites that were primarily located in their neural tissues where these RNA edits could be happening. Eisenberg and study co-author Joshua Rosenthal extended their research into octopuses and their neural networks. They wanted to know how these cephalopods with complicated and well-evolved brains handle the wide range of temperatures they are exposed to. 

DNA mutations typically allow organisms to adapt over long periods of time and over multiple generations. RNA editing is a common, flexible, and temporary way to adapt to changes in the environment–like seasonal temperature. 

“There’s often a contrast between this and CRISPR genome editing,” Rosenthal, a biologist at the University of Chicago-affiliated Marine Biological Laboratory, tells PopSci. “CRISPR genome editing is this artificial process that is designed to make changes in DNA, which would be kind of permanent from the time that changes are made throughout the life of the organism. RNA gives you the chance to do things temporarily.”

When RNA editing changes protein structures, the process is called RNA recoding. It’s pretty rare—except in octopuses and squid. Humans have millions of editing sites that affect less than three percent of our genes, but coleoid or “smart” cephalopods can recode the majority of their neural proteins.

“In the context outside of cephalopods, the main way to change the [protein] sequence and get a new kind of protein is through mutation and evolution,” study co-author and St. Francis University biologist Matthew Birk tells PopSci. “That takes generations and hundreds and thousands of years, while this is days. That was very exciting.”

[Related: Slap another cephalopod on the vampire squid’s family tree.]

In this new study, the team worked with California two-spot octopuses in a laboratory setting and in the wild. This species is the first octopus to have their genome sequenced,  and they are a reliable proxy for other octopuses. Wild octopuses are exposed to quick changes in temperature like when they dive to colder depths or during upwelling events and slower changes like when the seasons shift. 

They acclimated wild-caught adult octopuses to warm (71.6ºF) or cold (55.4ºF) waters in tanks and after several weeks, they compared the RNA transcripts for the acclimated octopuses to the genome to find signs of RNA editing.  

“One surprising finding was the fact that so many proteins, so many editing sites had changed upon temperature change, and all of them almost all of them in the same direction,” says Eisenberg. 

Editing occurred at around 30 percent or more than 20,000 individual places on the genome. The proteins edited tended to be neural proteins, and almost all edited sites sensitive to temperature swings were more highly edited in the cold, according to Eisenberg.

To see how quickly these changes occurred, they investigated the reaction in tiny thumbnail-sized juvenile octopuses. They gradually heated or cooled the tanks from 57.2°F up to 93.2°F and vice versa in hourly increments over about 20 hours. After measuring RNA editing before the temperature change, immediately after the change, and four days later, the team was surprised by just how rapidly it occurred. Birk says that changes were happening in less than one day, and their new steady levels were present four days after and remained for a month. 

The team also started investigating if recoding impacted protein structure function. They focused on two proteins that are critical for nervous system function—kinesin and synaptotagmin. They found evidence that the recoding changed the structures in the proteins that would impact how they function.  

“I’m really interested to see if this extends beyond physical environmental factors. If social context can influence the way you encode your nervous system, that’s a pretty interesting concept,” says Rosenthal. “I want to know what underlies this high level recoding of messenger RNAs.”

[Related: Argonaut octopuses are enigmatic—down to their self-made ‘shells.’]

Understanding more about this RNA editing and recoding could be applied to therapeutics in humans. Rosenthal and Eisenberg are working on a grant project from the National Institutes of Health to see if RNA editing can be used as a non addictive treatment for opioids. 

Studies like these are also satisfying the ever growing appetite for knowledge about our eight legged aquatic friends. “I feel like people understand or know octopuses pretty well. There’s all these fascinating things that we can physically see,” says Birk. “Now, we’re starting to understand more and more that they’re fascinating even at a molecular level. They are strange and inspire curiosity.”

The post Octopuses rewrite their own RNA to survive freezing temperatures appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Despite centuries of taboo and titillation, masturbation in primates appears to serve an evolutionary purpose. A study published June 6 in the journal Proceedings of The Royal Society B, found that self-stimulating increases reproductive success and helps primates avoid sexually transmitted infections (STI), at least in males. 

[Related from PopSci+: These sex toys are designed to heal, one orgasm at a time.]

Self-pleasure is common across the animal kingdom, but is particularly frequent in primates including humans. The behavior was considered by some scientists to be either pathological or simply a by-product of sexual arousal. Recorded observations were also too fragmented to fully understand masturbation’s distribution, evolutionary history, or adaptive significance. 

In this new study, a team of researchers built a dataset on primate masturbation from close to 400 sources, including 246 published academic papers, and 150 questionnaires and personal communications from zookeepers and primatologists. To understand why and when the practice evolved in both females and males, the authors tracked the distribution of autosexual behavior across primates.

They found that masturbation has a long evolutionary history amongst primates, and was likely present in the common ancestry of all monkeys and apes, humans included. What was less clear is whether the common ancestor of other primates—lemurs, lorises and tarsiers—masturbated, largely because there was less data on these groups.

The team tested multiple hypotheses to better understand why this seemingly non-functional trait would evolve. According to the postcopulatory selection hypothesis, masturbation aids successful fertilization that can be achieved in various ways. 

Masturbation without ejaculation can increase arousal before sexual intercourse, which may be a useful tactic for low-ranking primate males that are likely to be interrupted during sex. 

Masturbation with ejaculation allows males to shed their more inferior semen, which leaves the fresh, high-quality semen available for mating. This super semen may be more likely to outcompete the semen of other males, which is necessary in primate communities with steep competition for mates. The study found support for this second hypothesis, namely that male masturbation co-evolved within multi-male mating systems where competition between males is high.

[Related: Scientists think they found a 2,000-year-old dildo in ancient Roman ruins.]

According to the pathogen avoidance hypothesis, male masturbation reduces the chance of contracting an STI by cleansing the urethra with ejaculate. The team also found evidence to support this hypothesis, with the data revealing that masturbation in males co-evolved with high STI load across the primate tree of life.

The significance of female masturbation remains less clear. While it is frequent, fewer studies and reports describe female self-pleasure.The team argues that more data on female sexual behavior is needed before understanding masturbation’s evolutionary role in females. 

“Our findings help shed light on a very common, but little understood, sexual behavior and represent a significant advance in our understanding of the functions of masturbation,” study co-author and University College London anthropologist Matilda Brindle said in a statement. “The fact that autosexual behavior may serve an adaptive function, is ubiquitous throughout the primate order, and is practiced by captive and wild-living members of both sexes, demonstrates that masturbation is part of a repertoire of healthy sexual behaviors.”

The post Super semen could be one reason why primates evolved to masturbate appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

This article was originally published on Undark.

It could have been a scene from Jurassic Park: ten golden lumps of hardened resin, each encasing insects. But these weren’t from the age of the dinosaurs; these younger resins were formed in eastern Africa within the last few hundreds or thousands of years. Still, they offered a glimpse into a lost past: the dry evergreen forests of coastal Tanzania.

An international team of scientists recently took a close look at the lumps, which had been first collected more than a century ago by resin traders and then housed at the Senckenberg Research Institute and Natural History Museum in Frankfurt, Germany. Many of the insects encased within them were stingless bees, tropical pollinators that can get stuck in the sticky substance while gathering it to construct nests. Three of the species still live in Africa, but two had such a unique combination of features that last year, the scientists reported them to be new to science: Axestotrigona kitingae and Hypotrigona kleineri.

Species discoveries can be joyous occasions, but not in this case. Eastern African forests have nearly disappeared in the past century, and neither bee species has been spotted in surveys conducted in the area since the 1990s, noted coauthor and entomologist Michael Engel, who recently moved from a position at the University of Kansas to the American Museum of Natural History. Given that these social bees are usually abundant, it’s unlikely that the people looking for insects had simply missed them. Sometime in the last 50 to 60 years, Engel suspects, the bees vanished along with their habitat.

“It seems trivial on a planet with millions of species to sit back and go, ‘Okay, well, you documented two stingless bees that were lost,’” Engel said. “But it’s really far more troubling than that,” he added, because scientists increasingly recognize that extinction is “a very common phenomenon.”

The stingless bees are part of an overlooked but growing trend of species that are already deemed extinct by the time they’re discovered. Scientists have identified new species of bats, birds, beetles, fish, frogs, snails, orchids, lichen, marsh plants, and wildflowers by studying old museum specimens, only to find that they are at risk of vanishing or may not exist in the wild anymore. Such discoveries illustrate how little is still known about Earth’s biodiversity and the mounting scale of extinctions. They also hint at the silent extinctions among species that haven’t yet been described — what scientists call dark extinctions.

It’s critical to identify undescribed species and the threats they face, said Martin Cheek, a botanist at the Royal Botanic Gardens, Kew, in the United Kingdom, because if experts and policymakers don’t know an endangered species exists, they can’t take action to preserve it. With no way to count how many undescribed species are going extinct, researchers also risk underestimating the scale of human-caused extinctions — including the loss of ecologically vital species like pollinators. And if species go extinct unnoticed, scientists also miss the chance to capture the complete richness of life on Earth for future generations. “I think we want to have a full assessment of humans’ impact on nature,” said theoretical ecologist Ryan Chisholm of the National University of Singapore. “And to do that, we need to take account of these dark extinctions as well as the extinctions that we know about.”

Many scientists agree that humans have pushed extinctions higher than the natural rate of species turnover, but nobody knows the actual toll. In the tens of millions of years before humans came along, scientists estimate that for every 10,000 species, between 0.1 and 2 went extinct each century. (Even these rates are uncertain because many species didn’t leave behind fossils.) Some studies suggest that extinction rates picked up at least in the past 10,000 years as humans expanded across the globe, hunting large mammals along the way.

Islands were particularly hard hit, for instance in the Pacific, where Polynesian settlers introduced pigs and rats that wiped out native species. Then, starting in the 16th century, contact with European explorers caused additional extinctions in many places by intensifying habitat loss and the introduction of invasive species — issues that often continued in places that became colonies. But again, scientists have a poor record of biodiversity during this time; some species’ extinctions were only recognized much later, most famously the dodo, which had disappeared by 1700 after 200 years of Europeans hunting and then settling on the island in the Indian Ocean island it inhabited.

Key drivers of extinction, such as industrialization, have ramped up ever since. For the past century, some scientists have estimated an average of 200 extinctions per 10,000 species— levels so high that they believe they portend a mass extinction, a term reserved for geological events of the scale of the ordeal that annihalated the dinosaurs 66 million years ago. Yet some scientists, including the authors of those estimates, caution that even these numbers are conservative. The figures are based on the Red List compiled by the International Union for Conservation of Nature, or IUCN, a bookkeeper of species and their conservation statuses. As several experts have noted, the organization is slow to declare species extinct, wary that if the classification is wrong, they may cause threatened species to lose protections.

The Red List doesn’t include undescribed species, which some estimate could account for roughly 86 percent of the possibly 8.7 million species on Earth. That’s partly due to the sheer numbers of the largest species groups like invertebrates, plants, and fungi, especially in the little-explored regions around the tropics. It’s also because there are increasingly fewer experts to describe them due to a widespread lack of funding and training, noted conservation ecologist Natalia Ocampo-Peñuela of the University of California, Santa Cruz. Ocampo-Peñuela told Undark that she has no doubt that many species are going extinct without anyone noticing. “I think it is a phenomenon that will continue to happen and that it maybe has happened a lot more than we realize,” she said.

Studies of animal and plant specimens in museum and herbaria collections can uncover some of these dark extinctions. This can happen when scientists take a closer look at or conduct DNA analysis on specimens believed to represent known species and realize that these have actually been mislabeled, and instead represent new species that haven’t been seen in the wild in decades. Such a case unfolded recently for the ichthyologist Wilson Costa of the Federal University of Rio de Janeiro, who has long studied the diversity of killifish inhabiting southeastern Brazil’s Atlantic Forest. These fish live in shady, tea-colored acidic pools that form during the rainy season and lay eggs that survive through the dry period. These fragile conditions make these species extremely vulnerable to changes in water supply or deforestation, Costa wrote to Undark via email.

In 2019, Costa discovered that certain fish specimens collected in the 1980s weren’t members of Leptopanchax splendens, as previously believed, but actually represented a new species, which he called Leptopanchax sanguineus. With a few differences, both fish sport alternating red and metallic blue stripes on their flanks. While Leptopanchax splendens is critically endangered, Leptopanchax sanguineus hasn’t been spotted at all since its last collection in 1987. Pools no longer form where it was first found, probably because a nearby breeding facility for ornamental fish has diverted the water supply, said Costa, who has already witnessed the extinctions of several killifish species. “In the case discussed here, it was particularly sad because it is a species with unique characteristics and unusual beauty,” he added, “the product of millions of years of evolution stupidly interrupted.”

Similar discoveries have come from undescribed specimens, which exist in troves for diverse and poorly-studied groups of species, such as the land snails that have evolved across Pacific Islands. The mollusk specialist Alan Solem estimated in 1990 that, of roughly 200 Hawaiian species of one snail family, the Endodontidae, in Honolulu’s Bishop Museum, fewer than 40 had been described. All but a few are now likely extinct, said University of Hawaii biologist Robert Cowie, perhaps because invasive ants feasted off the snails’ eggs, which this snail family carries in a cavity underneath their shells. Meanwhile, Cheek said he’s publishing more and more new plant species from undescribed herbaria specimens that are likely already extinct in the wild.

Sometimes, though, it’s hard to identify species based on individual specimens, noted botanist Naomi Fraga, who directs conservation programs at the California Botanic Garden. And describing new species is not often a research priority. Studies that report new species aren’t often cited by other scientists, and they typically also don’t help towards pulling in new funding, both of which are key to academic success, Cheek said. One 2012 study concluded it takes an average of 21 years for a collected species to be formally described in the scientific literature. The authors added that if these difficulties — and the general dearth of taxonomists — persist, experts will continue to find extinct species in museum collections, “just as astronomers observe stars that vanished thousands of years ago.”

Museum records may only represent a fraction of undescribed species, causing some scientists to worry that many species could disappear unnoticed. For some groups, like snails, this is less likely, as extinct species may leave behind a shell that serves as a record of their existence even if collectors weren’t around to collect live specimens, noted Cowie. For instance, this allowed scientists to identify nine new and already-extinct species of helicinid land snails by combing the Gambier Islands in the Pacific for empty shells and combining these with specimens that already existed in museums. However, Cowie worries about the many invertebrates such as insects and spiders that won’t leave behind long-lasting physical remains. “What I worry about is that all this squishy biodiversity will just vanish without leaving a trace, and we’ll never know existed,” Cowie said.

Even some species that are found while they are still alive are already on the brink. In fact, research suggests that it’s precisely the newly described species that tend to have the highest risk of going extinct. Many new species are only now being discovered because they’re rare, isolated, or both — factors that also make them easier to wipe out, said Fraga. In 2018 in Guinea, for instance, botanist Denise Molmou of the National Herbarium of Guinea in Conakry discovered a new plant species which, like many of its relatives, appeared to inhabit a single waterfall, enveloping rocks amid the bubbly, air-rich water. Molmou was the last known person to see it alive.

Just before her team published their findings in the Kew Bulletin last year, Cheek looked at the waterfall’s location on Google Earth. A reservoir, created by a hydroelectric dam downriver, had flooded the waterfall, surely drowning any plants there, Cheek said. “Had we not got in there, and Denise had not gotten that specimen, we would not know that that species existed,” he added. “I felt sick, I felt, you know, it’s hopeless, like what’s the point?” Even if the team had known at the point of discovery that the dam was going to wipe it out, Cheek said, “it’d be quite difficult to do anything about it.”

While extinction is likely for many of these cases, it’s often hard to prove. The IUCN requires targeted searches to declare an extinction — something that Costa is still planning on doing for the killifish, four years after its discovery. But these surveys cost money, and aren’t always possible.

Meanwhile, some scientists have turned to computational techniques to estimate the scale of dark extinction, by extrapolating rates of species discovery and extinctions among known species. When Chisholm’s group applied this method to the estimated 195 species of birds in Singapore, they estimated that 9.6 undescribed species have vanished from the area in the past 200 years, in addition to the disappearance of 58 known species. For butterflies in Singapore, accounting for dark extinction roughly doubled the extinction toll of 132 known species.

Using similar approaches, a different research team estimated that the proportion of dark extinctions could account for up to just over a half of all extinctions, depending on the region and species group. Of course, “the main challenge in estimating dark extinction is that it is exactly that: an estimate. We can never be sure,” noted Quentin Cronk, a botanist of the University of British Columbia who has produced similar estimates.

Considering the current trends, some scientists doubt whether it’s even possible to name all species before they go extinct. To Cowie, who expressed little optimism extinctions will abate, the priority should be collecting species, especially invertebrates, from the wild so there will at least be museum specimens to mark their existence. “It’s sort of doing a disservice to our descendants if we let everything just vanish such that 200 years from now, nobody would know the biodiversity — the true biodiversity — that had evolved in the Amazon, for instance,” he said. “I want to know what lives and lived on this Earth,” he continued. “And it’s not just dinosaurs and mammoths and what have you; it’s all these little things that make the world go round.”

Other scientists, like Fraga, find hope in the fact that the presumption of extinction is just that — a presumption. As long as there’s still habitat, there’s a slim chance that species deemed extinct can be rediscovered and returned to healthy populations. In 2021, Japanese scientists stumbled across the fairy lantern Thismia kobensis, a fleshy orange flower only known from a single specimen collected in 1992. Now efforts are underway to protect its location and cultivate specimens for conservation.

Fraga is tracking down reported sightings of a monkeyflower species she identified in herbaria specimens: Erythranthe marmorata, which has bright yellow petals with red spots. Ultimately, she said, species are not just names. They are participants of ecological networks, upon which many other species, including humans, depend.

“We don’t want museum specimens,” she said. “We want to have thriving ecosystems and habitats. And in order to do that, we need to make sure that these species are thriving in, you know, populations in their ecological context, not just living in a museum.”

Katarina Zimmer is a science journalist. Her work has been published in The Scientist, National Geographic, Grist, Outside Magazine, and more.

This article was originally published on Undark. Read the original article.

The post These species were discovered in museum collections. They might already be extinct. appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Cold weather is prime time for humans to stay inside and snuggle up with loved ones. For our primate cousins, cuddling may even keep them healthy, as frosty temps and social bonds seem to go together like hot chocolate and marshmallows. Chilly temperature behavior, as it turns out, may also alter the course of evolution.

A study published June 1 in the journal Science found that a species’ long-term adaptation to life in extremely cold climates led to the evolution of successful social behaviors. Asian colobines living in colder regions saw genetic changes and adaptations to their social behaviors including extended care by mothers, which increased infant survival and the primates’ ability to live in the large complex multilevel societies we see today.

[Related: These primate ancestors were totally chill with a colder climate.]

An international team of researchers from the United States, China, the United Kingdom, and Australia studied how langurs and odd-nosed monkeys adapted over time. These members of the colobine family are leaf-eating monkeys that have been on Earth for about 10 million years. Their ancient ancestors dispersed across the planet’s continents and learned to live in tropical, temperate, and colder climates. 

“Virtually all primates are social and live in social groups,” study co-author and  University of Illinois Urbana-Champaign anthropologist Paul A. Garber said in a statement. “But the groups differ in size and cohesiveness. There are those that live in units of two or three individuals and others living in communities of up to 1,000 individuals.”

According to Garber, genomic studies suggest that the harem unit of organization—one male with two or more females and their offspring—was the ancestral norm for Asian colobines. Males are intolerant of other rival males and will fight to protect their turf. In some species, the females will stay with their natal group, while in others, both sexes leave to join or form new harems.

More complex societies formed over time. Some odd-nosed monkeys still form harems, but aren’t territorial. “This means their group territories can overlap and there are times they may come together to forage, rest and travel,” said Garber. 

Snub-nosed monkeys form a multilevel or modular society where multiple harems remain together throughout the year and create a large, cohesive breeding band. The team on this study recorded a society of about 400 individuals and breeding between individuals from different harems was common in golden snub-nosed monkeys. This inter-harem breeding happened roughly 50 percent of the time.

The study used ecological, geological, fossil, behavioral, and genomic analyses, and found that the colobine primates that lived in colder places tended to live in larger and more complex social groups. The glacial periods over the past six million years likely promoted the selection of genes that are involved in cold-related energy metabolism and hormonal regulation in the nervous system.

[Related: Baboons can recover from childhood trauma with a little help from their friends.]

Black-and-white snub-nosed monkeys in some parts of China live in low-oxygen elevations up to about 13,500 feet where night time temperatures can drop below zero on the coldest evenings. The Odd-nosed monkeys living in extremely cold locations developed more efficient pathways for dopamine and oxytocin. Oxytocin particularly is an important neurohormone for social bonding and this hormonal efficiency may lengthen the time a mother monkey takes care of her baby. This led to longer periods of breast-feeding and increase in infant survival.  

These adaptive changes appear to have further strengthened the relationships between individual monkeys, increased tolerance between males, and encouraged the evolution of more complex and larger multi level societies that go a long way. Strong social bonds can even help gut bacteria health in some monkeys.

In future studies, the team is interested in studying how changes in mating and social behavior may be the result of genetic changes from past environments and other social factors from the past. 

“With climate change becoming an hugely important environmental pressure on animals, it is hoped that this study will raise awareness for the need to investigate what course social evolution will take as the prevailing climate changes,” study co-author and University fo Western Australia biological anthropologist Cyril Grueter said in a statement. “Our finding that complex multilevel societies have roots stretching back to climatic events in the distant evolutionary past also has implications for a reconstruction of the human social system which is decidedly multilevel.”

The post Chilly climates may have forged stronger social bonds in some primates appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Over three million years ago, a 500-plus pound marsupial roamed Australia, winning the prize of the continent’s first long-distance walking champion. In a study published May 31 in the Journal of Royal Society Open Science, a team of scientists described the discovery of this new genus using advanced 3D scans and the partial remains of a 3.5 million year old specimen. 

Most earlier studies on this group have focused on its skull since other skeletal remains are rare in Australia’s fossil record. The skeleton described in this new study, found at Kalamurina Station in southern Australia in 2017, is special since it is the first that was found with associated soft tissue structures. The authors used 3D-scanning to compare the partial skeleton with other diprotodontid material housed in collections all over the world. A hard concretion that formed shortly after the animal died encased its foot, and CT scans revealed the soft tissue impressions on the outline of its footpad.

[Related: Giant wombats the size of small cars once roamed Australia.]

The new genus Ambulator, meaning “walker” or “wanderer,” had four giant legs which would have helped it roam long distances in search of food and water compared to its earlier relatives. It belongs to the Diprotodontidae family, an extinct family of big, four-legged, herbivorous marsupials that lived in New Guinea and Australia. The largest species was Diprotodon optatum, which was about the size of a car and weighed almost 6,000 pounds. Diprotodontids were an integral part of the region’s ecosystem before going extinct about 40,000 years ago. 

“Diprotodontids are distantly related to wombats – the same distance as kangaroos are to possums – so unfortunately there is nothing quite like them today. As a result, paleontologists have had a hard time reconstructing their biology,” study author and Flinders University PhD student Jacob van Zoelen said in a statement. 

Ambulator keanei lived during the Pliocene era when Australia saw an increase in grasslands and open habitats become more dry. To have enough to eat and drink, diprotodontids likely had to travel great distances. 

“We don’t often think of walking as a special skill but when you’re big any movement can be energetically costly so efficiency is key,” said van Zoelen. “Most large herbivores today such as elephants and rhinoceroses are digitigrade, meaning they walk on the tips of their toes with their heel not touching the ground.  “

Diprotodontids are plantigrade animals, which means that their heel-bone makes contact with the ground as they walk. This is similar to the way humans walk and helps distribute the weight while walking, but does use more energy when running. According to van Zoelen, diprotodontids also have extreme plantigrady in their hands. The bone of the wrist is modified into a secondary heel and this “heeled hand” may have made early reconstructions of the animal look a little bit bizarre.

“Development of the wrist and ankle for weight-bearing meant that the digits became essentially functionless and likely did not make contact with the ground while walking.” said van Zoelen. “This may be why no finger or toe impressions are observed in the trackways of diprotodontids.”

The post This 500-pound Australian marsupial had feet made for walkin’ appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Efficiently standing up and walking and running on two feet  stands out among the traits that separates Homo sapiens from great apes—and we can owe a lot of that to a raised medial arch. While crucial, the mechanics behind bipedal walking are still a bit of an evolutionary mystery.  A study published May 30 in the journal Frontiers in Bioengineering and Biotechnology found that helpful and spring-like arches may have evolved for the purpose of helping us walk on two feet.

[Related: Foraging in trees might have pushed human ancestors to walk on two feet.]

The team found that the recoil of a flexible arch repositions in the ankle upright for more efficient walking and is particularly effective for running. 

“We thought originally that the spring-like arch helped to lift the body into the next step,” study co-author and University of Wisconsin-Madison biomechanical engineer Lauren Welte said in a statement. “It turns out that instead, the spring-like arch recoils to help the ankle lift the body.”

The raised arch in the center of the human foot is believed to give hominins more leverage while walking upright. When arch motion is restricted, like it could be in those with more flat feet, running demands more energy from the body. Arch recoil could potentially make our species more efficient by propelling the body’s center of mass forward, essentially making up for the mechanical work that the muscles would have to do otherwise.

In this new study, the team selected seven participants with varying arch mobility and filmed their walking and running patterns with high-speed x-ray motion capture cameras. The team measured the height of each participant’s arch and took CT scans of their right feet. They also created rigid models that were compared to the measured motion of the bones in the foot. Scientists then measured which joints added the most to arch recoil and the contribution of arch recoil to center of mass and ankle propulsion.

Surprisingly, they found that a rigid arch without recoil caused the foot to prematurely leave the ground, likely decreasing the efficiency of the calf muscle. A rigid arch also leaned the ankle bones too far forward. A forward lean looks more like the posture of walking chimpanzees instead of the straight upright stance of a human gait.

A flexible arch helped reposition the ankle upright, allowing the leg to push off the ground more effectively. This effect is greater while running, suggesting that a flexible arch for more efficient running may have been a desired evolutionary trait.

The team also found that a joint between two bones in the medial arch–the navicular and the medial cuneiform–is crucial to flexibility. Investigating the changes in this joint over time could help scientists track the development of bipedalism in our own fossil record. 

[Related: The Monty Python ‘silly walk’ could replace your gym workout.]

“The mobility of our feet seems to allow us to walk and run upright instead of either crouching forward or pushing off into the next step too soon,” study co-author and Queen’s University mechanical and materials engineer Michael Rainbow said in a statement.

These findings and understanding more about arch flexibility could help people who have rigid arches due to illness or injury. Their hypothesis still needs more testing, but could help solve a plethora of modern-day foot dilemmas. 

“Our work suggests that allowing the arch to move during propulsion makes movement more efficient,” said Welte. “If we restrict arch motion, it’s likely that there are corresponding changes in how the other joints function.”

The post Evolution of human foot arches put the necessary pep in our upright steps appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

As they creep through tropical environments appearing not to have a care in the world, sloths give off some of the chillest vibes in the animal kingdom. This relaxed and elusive nature does make studying sloths a bit difficult, but a study published May 29 in the journal PeerJ Life & Environment is shedding some new light on activity patterns and behaviors adaptations of two sloth species.

[Related: Sloths aren’t the picky eaters we thought they were.]

The team looked at Bradypus variegatus and Choloepus hoffmanni, two sloth species that live in the lowland rainforests of Costa Rica’s Caribbean coast. Costa Rica is home to six species of sloths, who have the slowest digestive system of any animal on Earth. It can take the mammals two weeks to digest an entire meal, and they sleep about 20 hours a day to conserve energy. 

Using micro data loggers, the team continuously monitored the behavior of both three-toed sloths (Bradypus) and two-toed sloths (Choloepus) for periods ranging from days to weeks. These recordings enabled the team to explore how fluctuating environmental influences sloth activity and how that correlates with their uniquely chill and low-energy lifestyle. 

Choloepus sloths are cathemeral, meaning that they have irregular variable periods of activity throughout a 24-hour cycle. Cathemeral behavior allows them to take advantage of better environmental conditions while minimizing the risk of predation. 

The study also observed a large amount of variability in activity levels between the animals and also within individual sloths. This flexibility suggests that the animals have developed diverse strategies to adapt to their surroundings, which enhances their chances of survival when the environment fluctuates. 

The team initially expected that daily temperatures, which can hit the mid-90s, would influence sloth activity, but their observations did not support that initial hypothesis. However, Bradypus sloths did increase their night time activity on colder nights and the nights that followed colder days. The authors believe that this indicates a potential correlation between sloth behavior and temperature variations.

[Related: Our bravest ancestors may have hunted giant sloths.]

While this study adds more understanding to sloth ecology, it also highlights the importance of preserving and protecting tropical rainforests and their unique inhabitants. According to Global Forest Watch, Costa Rica lost about 2.4 percent of its forest cover between 2000 and 2020, but the country has gained international recognition for its efforts to mitigate climate change and promote animal welfare.

“Understanding the drivers of sloth activity and their ability to withstand environmental fluctuations is of growing importance for the development of effective conservation measures, particularly when we consider the vulnerability of tropical ecosystems to climate change and the escalating impacts of anthropogenic activities in South and Central America,” the team wrote in the paper.

As these tropical ecosystems become more vulnerable due to human-made climate change, understanding wildlife patterns are crucial for conservation methods. While long-term observational research is a challenge, this study could pave the way for more studies on this cryptic and elusive species. 

The post Sloth schedules are surprisingly flexible appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

The armadillo is beloved for its ability to scrunch itself up in a ball with their protective flexible shells. They’ve long been considered the only living mammals with these reptilian and fish-like suits of bony or scaly armor instead of hairy mammalian skin. However, a study published May 24 in the journal iScience, shows that African spiny mice actually produce the same spiny structures beneath the skin of their tails, which has gone largely undetected by scientists.

[Related: How science came to rely on the humble lab rat.]

African spiny mice are small to medium sized rodents with spiny hairs on their upper body, large eyes and ears, and scaly tails. Some species are found in Egypt, other parts of eastern Africa, Saudi Arabia, and Pakistan and while others are native to South Africa.  

A team of scientists made this spiny discovery while conducting routine CT scanning of museum specimens for the openVertebrate program. 

“I was scanning a mouse specimen from the Yale Peabody Museum, and the tails looked abnormally dark,” co-author and director of Florida Museum of Natural History’s digital imaging laboratory Edward Stanley said in a statement. 

Stanley initially assumed the discoloration was caused by an imperfection that was introduced when the specimen was preserved, but analysis of the X-Rays revealed an unmistakable feature that he was intimately familiar with.

“My entire PhD was focused on osteoderm development in lizards,” he said. “Once the specimen scans had been processed, the tail was very clearly covered in osteoderms.”

Osteoderms are the bony deposits that form scales or plates on the skin. They are also distinct from the scales of pangolins or the quills of hedgehogs and porcupines. These parts are composed of keratin, the same tissue that makes up hair, skin, and nails.

Osteoderms on spiny mice have been observed since the mid-1970s. A 2012 study demonstrated spiny mice can regenerate injured tissue without scarring. This ability is very common among reptiles and invertebrates, but was previously unknown in mammals. While mammalian skin is particularly fragile, spiny mice can heal twice as fast as their rodent relatives.

Spiny mice belong to four genera in the subfamily Deomyinae, but other than similarities in their DNA and possibly the shape of their teeth, scientists have been unable to find a single shared feature among the species of this group that distinguishes them from other rodents.

[Related: This newly discovered gecko can literally squirm right out of its skin.]

The team scanned additional museum specimens from all four genera and found that the spiny mice tails were covered in the same sheather of bone. Gerbils are the closest relatives of Deomyinae and they do not have osteoderms, which means that this trait likely evolved only once in the ancestor of spiny mice. 

“Spiny mice can regenerate skin, muscle, nerves, spinal cord and perhaps even cardiac tissue, so we maintain a colony of these rare creatures for research,” co-author and University of Florida biologist Malcolm Maden said in a statement. 

Maden and his team are mapping the genetic pathways that give spiny mice these healing powers to hopefully find a model for human tissue regeneration. The team further analyzed the development of spiny mice osteoderms and confirmed that they were similar to those of armadillos, but likely evolved independently. 

The post African spiny mouse joins a small but mighty group of bony plated mammals appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

If Spiderman and Antman took their DNA and mixed it together in a petri dish, the result might be something like the spider species Siler collingwoodi (S. collingwoodi). This tiny, colorful, jumping spider found in China and Japan uses a combination of camouflage and some award-worthy mimicry to deter some hungry predators. In a stressful scenario, these spiders will imitate the way an ant walks to avoid being eaten.

[Related: Black widows battle their even deadlier cousins in a brutal spider war.]

A study published May 17 in the journal iScience found that the combo of camouflage and ant mimicry works to evade spiders that eat other spiders, but not hungry praying mantises. It’s advantageous to mimic an ant because they are typically not very tasty, and can have spiny defenses, chemical repellents, or venom. Not to mention, species of “exploding” ants like Colobopsis saundersi that are not afraid to fight and bite back. While scientists already knew that S. collingwoodi walked like an ant, the team on this study were curious how accurate the mimicry is, whether it imitates multiple species of ants, and how effective it is at discouraging predators. 

“Unlike typical ant-mimicking spiders that mimic the brown or black body color of ants, S. collingwoodi has brilliant body coloration,” co-author and Peking University in China ecologist Hua Zeng said in a statement. “From a human’s perspective, it seems to blend well with plants in its environment, but we wanted to test whether their body coloration served as camouflage to protect against predators.”

To better understand how these ant-inspired theatrics help the spiders avoid becoming dinner, the team collected wild ant-mimicking spiders from four spots in southern Hainan, China, and brought them back to the lab. They also collected another type of jumping spider that does not mimic ants as a comparison and five co-occurring ant species as potential models.  

The team then compared and characterized how the insects and arachnids moved in terms of how they used their individual limbs, their speed, acceleration, and whether they followed a straight path or took a more roundabout way. 

Inside of jumping like most jumping spiders, S. collingwoodi scuttle around like ants. They raise their front legs to mimic an ant’s antennae, bob their abdomens, and lift their legs to walk more ant-like. Out of the five ant species studied, the spider’s style of walking more closely resembled three of the smaller ant species that are closer in size.

“S. collingwoodi is not necessarily a perfect mimic, because its gait and trajectory showed high similarity with multiple ant species,” said Zeng. “Being a general mimic rather than perfectly mimicking one ant species could benefit the spiders by allowing them to expand their range if the ant models occupy different habitats.”

Then it was time to test these defenses against two likely predators. Portia labiata and the praying mantis. Portia labiata is a similarly sized jumping spider with color vision who specializes in preying upon other spiders. The praying mantis is a more generalist predator that has a monochromatic visual system–meaning it has trouble telling multiple colors apart. 

[Related: Jumping spiders might be able to sleep—perchance to dream.]

To see how the color camouflaging was working, they modeled how the two predators would perceive S. collingwoodi relative to the other prey species. They used a background of two plants that the spiders live on—the red-flowering West Indian jasmine and the Fukien tea tree The ant-mimicking spiders were better camouflaged from both predators on the jasmine plant than on the tea tree plant.

The predators were more likely to attack the non-mimicking spider than the ones that imitate ants. Out of 17 trials, the spider launched five attacks—all of them were launched towards a non-mimicking spider. However, praying mantises attacked both prey species with equal readiness.

“We initially thought that both predators would behave similarly in the anti predation experiments, but in fact the simulated ant locomotion of Siler collingwoodi only worked for the jumping spider predator, while the praying mantis showed indiscriminate attacks on both ants and mimics,” co-author and Peking University evolutionary ecologist Wei Zhang said in a statement. 

It is possible that this difference might be driven by each predator’s likelihood of being injured if they eat an ant. The praying mantises are much larger than their prey, and they have a better chance of eating spiny ants without risking catastrophic injury. Predatory spiders do not have this margin for error. 

“For the spider predator, a random attack on an ant could result in injury,” says Zhang, “so they are very careful predators and will only attack if they can distinguish S. collingwoodi from ants with a high degree of certainty.”

The post This spider pretends to be an ant, but not well enough to avoid being eaten appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Up until 100 million years ago, butterflies were night creatures. Only nocturnal moths were living on Earth until some rogue moths began to fly during the day. These enterprising members of the order Lepidoptera took advantage of the nectar-rich flowers that had co-evolved with bees by flying during the day. From there, close to 19,000 butterfly species were born.

[Related: Save caterpillars by turning off your outdoor lights.]

In 2019, a large-scale analysis of DNA helped solve the question of when they evolved. Now,  the mystery of where in the world colorful winged insects evolved plagues lepidopterists and museum curators. A study published May 15 in the journal Nature Ecology and Evolution found that butterflies likely evolved in North and Central America, and they forged strong botanical bonds with host plants as they settled around the world.

Getting to this conclusion took a four-dimensional puzzle that makes 3D chess look like a game of Candyland. Scientists from multiple countries had to assemble a massive “butterfly tree of life” using 100 million years of natural history on their distribution and favorite plants, as well as the DNA of more than 2,000 species representing 90 percent of butterfly genera and all butterfly families. 

Within the data were 11 rare butterfly fossils that proved to be crucial pieces to the story.  Butterflies are not common in the fossil record due to their thin wings and very threadlike hair. The 11 in this study were used as calibration and comparison points on the genetic trees, so the team could record timing of key evolutionary events.

They found that butterflies first appeared somewhere in central and western North America. 100 million years ago, North America was bisected by an expansive seaway called the Western Interior Seaway. Present day Mexico was joined in an arc with the United States, Canada, and Russia. North and South America were also separated by a strait of water that butterflies had little difficulty crossing.

The study believes that butterflies took a long way around to Africa, first moving into Asia along the Bering Land Bridge. They then radiated into Southeast Asia, the Middle East, and eventually the Horn of Africa. They were even able to reach India, which was an isolated island separated by miles of open sea at this time. 

[Related: The monarch butterfly is scientifically endangered. So why isn’t it legally protected yet?]

Australia was still connected to Antarctica, one of the last remnants of the supercontinent Pangaea. Butterflies possibly lived in Antarctica when global temperatures were warmer, and made their way north towards Australia before the landmasses broke up. 

Butterflies likely lingered along the western edge of Asia for up to 45 million years before making the journey into Europe. The effects of this pause are still apparent today, according to the authors. 

“Europe doesn’t have many butterfly species compared to other parts of the world, and the ones it does have can often be found elsewhere. Many butterflies in Europe are also found in Siberia and Asia, for example,” study co-author and curator of lepidoptera at the Florida Museum of Natural History Akito Kawahara said in a statement. 

Once butterflies were established all over the world, they rapidly diversified alongside their plant hosts. Nearly all modern butterfly families were on Earth by the time dinosaurs went extinct 66 million years ago. Each butterfly family appears to have had a special affinity for a specific group of plants.

“We looked at this association over an evolutionary timescale, and in pretty much every family of butterflies, bean plants came out to be the ancestral hosts,” Kawahara said. “This was true in the ancestor of all butterflies as well.”

Over time, bean plants have increased their roster of pollinators to include multiple types of bees, flies, hummingbirds, and mammals, while butterflies have similarly expanded their palate. These botanical partnerships helped make butterflies blossom from a minor offshoot of moths to one of the world’s largest groups of insects, according to the study.

“The evolution of butterflies and flowering plants has been inexorably intertwined since the origin of the former, and the close relationship between them has resulted in remarkable diversification events in both lineages,” study co-author and Florida Museum curator Pamela Soltis said in a statement. 

The post A ‘butterfly tree of life’ reveals the origins of these beautiful insects appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

After an asteroid that wiped out the dinosaurs struck the Earth, the prehistoric giants lost their dominion over the planet. The mammals that rose up about 66 million years ago during the Eocene Epoch had some big shoes to fill—and they certainly grew into the challenge over time.

[Related: We’re one step closer to identifying the first-ever mammals.]

In a study published May 11 in the journal Science, found that a family of extinct rhinoceros-like herbivores called brontotheres began their time on Earth about the size of a dog, but evolved to reach elephant size over a relatively short amount of time. Brontotheres also may have not reached its full size potential before it went extinct roughly 34 million years ago due to changes in their environment.

With the dinosaurs gone at the end of the Cretaceous period (145 million to 66 million years ago), the mammals of the world had significantly less competition for resources, and scientists believe this led to their success as a family. Brontotheres was one of the biggest winners among mammals, and grew from about coyote-sized, 40 pound creatures into 2,000 pound goliaths. According to the study, they did this over a period of only 16 million years, which is very quick in evolutionary terms.

Brontothere means “thunder beasts,” and their powerful name was inspired by Lakota oral histories of violent thunderstorms accompanied by giants, according to the National Park Service.The animals lived in Asia, Europe, and North America. Most species weighed over a ton, but the biggest roamed what is now the South Dakota Badlands. These giants clocked in at about 8 feet tall and 16 feet long. They are the relatives of modern tapirs, horses, and rhinos, and were equipped with Y-shaped horns on their noses. 

The team of researchers on this brontothere size evolution study peered back at the evidence from the family’s fossil record and a family tree of 276 known brontothere individuals. They were fortunate that the fossil record shows most of their evolutionary record, and the team generated computer models to track how the genetic traits of different brontothere species changed. 

They also conducted phylogenetic analysis, or an evaluation of the evolutionary avenues that causes a new species to take shape. This helped them determine how such evolutionary changes may be linked or connected to their increase in body size. 

The data showed that body size actually evolved in both directions across brontothere species. Some would evolve bigger, while other times a species would evolve smaller. They found that the smaller species were more prone to extinction compared to their bigger cousins, and a trend of bulkier brontotheres persisted longer than the smaller species emerged.  

[Related from PopSci+: An ancient era of global warming could hint at our scorching future.]

Towards the end of the Eocene, the remaining brontotheres were true thunder beasts. Their status as megaherbivores likely benefited the beasts, with the smaller animals being more vulnerable to become a carnivore’s dinner. Competition from other big and small herbivores could hardly stand up to the beasts, according to the study.

Unfortunately, at this same time, the climate drastically changed from a more humid herbivore’s paradise to something much more dry. The brontotheres thus lost their evolutionary advantages when the previously lush and green ecosystem dried up. They eventually went extinct about 34 million years ago.

Further research into this family could model the ecological factors like ancient climate shifts that affected how much edible vegetation covered the planet and how it led to the demise of these megaherbivores.

The post Extinct ‘thunder beasts’ went from mini to massive in the blink of an evolutionary eye appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

The humble sea star is an ancient marine creature that possibly goes back about 480 million years. They are beloved in touch tanks in aquariums for their celestial shape, spongy skin, and arm suckers. These beautiful five-limbed echinoderms are also helping scientists figure out a crucial life process called tubulogenesis. 

[Related: What’s killing sea stars?]

A study published May 9 in the journal Nature Communications, examined this process of hollow tube formation in sea stars that provides a blueprint for how the organs of other creatures develop.

Tubulogenesis is the formation of various kinds of hollow, tube-like structures. in the body. These tubes eventually form blood vessels, digestive tracts, and even complex organs like the heart, kidneys and mammary glands. It is a basic and crucial process that occurs in the embryo stage, and abnormalities during these processes can cause dysfunctional, displaced, or non-symmetrical organs and even regeneration defects in structures like blood vessel. 

Little is known about the general mechanisms of the hollow tube formation during embryogenesis since animals all use very different strategies to form these tubular structures.

That’s where the sea star comes in. Their process of tubulogenesis is relatively easy to observe since their embryos are very transparent and can be observed without disturbing them. Not to mention, they breed in large numbers year round. This new study reveals the initiation and early stages of tube formation in the sea star Patiria miniata or bat star.

“Most of our organs are tubular, because they need to transport fluids or gasses or food or blood. And more complex organs like the heart start as a tube and then develop different structures. So, tubulogenesis is a very basic step to form all our organs,” study co-author and cell biologist Margherita Perillo of the University of Chicago-affiliated Marine Biological Laboratory said in a statement. 

Not only is the sea star an ideal because of its translucence, the researchers needed an animal that was along the base of the tree of life and evolved before the phylum Chordata– vertebrates including fish, amphibians, reptiles, birds, and mammals, Perillo adds.

Perillo and her colleagues used CRISPR gene editing and other techniques to analyze the gene functions in the sea stars and long time-lapse videos of developing larvae. The team worked out how the sea star generates the tubes that branch out from its gut. From these observations, they could define the basic tools needed for more advanced chordate tubular organs that may have developed. Now, they are getting closer to answering how organisms developed up from one cell into the more complex 3D tubular structures that make up various organisms. 

According to Perillo, in some organisms such as flies, “there is a big round of cell proliferation before all the cells start to make very complex migration patterns to elongate, change their shapes, and become a tube.”

[Related: These urchin-eating sea stars might be helping us reduce carbon levels.]

In other animals, including mammals, cell proliferation and migration occur together. The team found that in sea stars, cells can also proliferate and migrate at the same time in order for the tubes to form the way they do in vertebrate formation. The mechanism behind making organs must have already been established at the base or root of chordate evolution, according to the team. 

Beyond providing evolutionary insights into organ formation, sea stars can also aid in biomedical research. Perillo found that a gene called Six1/2 is a key regulator of the branching process in tube formation. If Six1/2 is taken out of mice, their kidneys form abnormally, but the mice that lack the gene also resist tumor formation, even if they are injected with tumor cells. Understanding this gene, that is overexpressed in cancer cells, may lead to new ways to study disease progression.  

“I can now use this gene to understand not only how our organs develop, but what happens to organs when we have a disease, especially cancer,” said Perillo. “My hope is that, in five to 10 years maximum, we will be able to use this gene to test how organs develop cancer and how cancer becomes metastatic.”

The post The blueprints for early organs may be hiding in sea stars appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

Before being outbred by Homo sapiens, Neanderthals could have been many things: including the world’s first weavers, artists, and even crab chefs. Their contributions may even go deeper—even to modern day faces. Genetic material from this now extinct crew  influences the shape of human noses today, according to new research. 

In a study published May 8 in the journal Communications Biology, an international team of researchers found a particular gene that leads to a taller nose (top to bottom) might be the product of natural selection when sentient humans adapted to colder climates after leaving the African continent.

[Related: Humans and Neanderthals could have lived together even earlier than we thought.]

“In the last 15 years, since the Neanderthal genome has been sequenced, we have been able to learn that our own ancestors apparently interbred with Neanderthals, leaving us with little bits of their DNA,” Kaustubh Adhikari, a co-author and statistical geneticist at University College London, said in a statement. “Here, we find that some DNA inherited from Neanderthals influences the shape of our faces. This could have been helpful to our ancestors, as it has been passed down for thousands of generations.”

The research team used data from over 6,000 volunteers from Brazil, Colombia, Chile, Mexico, and Peru with mixed European, Native American, and African ancestry. They compared their genetic information to photographs of their faces, and examined the distances between points on the face, like the edge of the lips to the tips of the nose to see how different facial traits might be associated with different genetic markers.

“Most genetic studies of human diversity have investigated the genes of Europeans; our study’s diverse sample of Latin American participants broadens the reach of genetic study findings, helping us to better understand the genetics of all humans,” Andres Ruiz-Linares, co-author and geneticist at University College London, said in a statement.

They found 33 new genome regions that are associated with face shape, and they could replicate 26 of them in comparisons with data from other ethnicities using participants in east Asia, Europe, or Africa.

[Related: Europeans looked down on Neanderthals—until they realized they shared their DNA.]

They looked at a genome region called ATF3, and found that many of those in the study with Native American ancestry had genetic material inherited from Neanderthals that contributes to nasal height. They compared that same genome region with those of east Asian ancestry from a different cohort and saw the same genetic material.  This gene region also has signs of natural selection, suggesting that it has an advantage for those carrying the genetic material.

“It has long been speculated that the shape of our noses is determined by natural selection; as our noses can help us to regulate the temperature and humidity of the air we breathe in, different shaped noses may be better suited to different climates that our ancestors lived in,” Qing Li, a co-author and scientist at China’s Fudan University, said in a statement. “The gene we have identified here may have been inherited from Neanderthals to help humans adapt to colder climates as our ancestors moved out of Africa.”

In 2021, this same team also found that genes influencing facial shapes were inherited from another extinct human species called the Denisovans. In that study, they found 32 gene regions that influence facial features like nose, lip, jaw, and brow shape.

The post How Neanderthal genetic material could influence nose shapes to this day appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.

There is truly no shortage of interesting courting and mating rituals throughout the animal kingdom. From trilobites “jousting” to win mates to the important pee sniffing rituals of giraffes, getting it on is serious business. And so is winning over a mate. 

[Related: Male California sea lions have gotten bigger and better at fighting.]

For the first time, scientists have found direct evidence that adult male woolly mammoths experienced an event called musth. Musth comes from the Hindi and Urdu word for intoxicated, and in the case of giant mammals like adult elephants, this is a testosterone-fueled event where the male sex hormone surges and aggression against rival males is heightened. 

The study, published online May 3 in the journal Nature, found evidence that testosterone levels are recorded within the growth layers of both elephant and mammoth tusks. In living male elephants, blood and urine tests recognized the elevated testosterone, but musth battles from its extinct relatives has only been inferred from to fossilized consequences of testosterone-fueled battle, such as pieces of tusk tips and skeletal injuries. 

In the study, an international team of researchers report the presence of annually recurring testosterone surges (up to 10 times higher than baseline levels) are present within a permafrost-preserved woolly mammoth tusk. 

The team sampled tusks from one adult African bull elephant from Botswana and two adult woolly mammoths: a male who roamed Siberia over 33,000 years ago and a roughly 5,597 year-old female that was discovered on Wrangel Island. This Arctic Ocean island used to be connected to northeast Siberia and is the last place where woolly mammoths survived up until about 4,000 years ago. 

“This study establishes dentin as a useful repository for some hormones and sets the stage for further advances in the developing field of paleoendocrinology,” study co-author and paleontologist at the University of Michigan Museum of Paleontology Michael Cherney said in a statement. “In addition to broad applications in zoology and paleontology, tooth-hormone records could support medical, forensic and archaeological studies.”

Hormones are signaling molecules that help regulate physiology and behavior. Testosterone in male vertebrates is part of the steroid group of hormones. Testosterone circulates throughout the bloodstream and accumulates in various tissues.   

[Related: How much acid should you give an elephant? These scientists learned the hard way.]

According the authors, their findings demonstrate that steroid records in teeth can provide scientists with meaningful biological information that can even persist for thousands of years.

“Tusks hold particular promise for reconstructing aspects of mammoth life history because they preserve a record of growth in layers of dentin that form throughout an individual’s life,” study co-author and U-M Museum of Paleontology curator Daniel Fisher said in a statement.  “Because musth is associated with dramatically elevated testosterone in modern elephants, it provides a starting point for assessing the feasibility of using hormones preserved in tusk growth records to investigate temporal changes in endocrine physiology.”

They team used CT scans to find the annual growth increments deep within the tusks, like tree rings. Modern elephant and ancient mammoth tusks are elongated upper incisor teeth, and only hold on to traces of testosterone and other steroid hormones. The chemical compounds are all incorporated into dentin, which is the mineralized tissue that makes up the interior portion of teeth. 

The study also required new methods to extract steroids from the tusk dentin with a mass spectrometer. Mass spectrometers identify chemical substances by sorting the ions present by their mass and charge. 

“We had developed steroid mass spectrometry methods for human blood and saliva samples, and we have used them extensively for clinical research studies. But never in a million years did I imagine that we would be using these techniques to explore ‘paleoendocrinology,'” study co-author and U-M endocrinologist Rich Auchus said in a statement. 

The results and the new measuring technique will likely further new approaches to investigating reproductive endocrinology, life history, and even disease patterns in modern and prehistoric context.

The post Male woolly mammoths had hormone-fueled bouts of aggression appeared first on Popular Science.

Articles may contain affiliate links which enable us to share in the revenue of any purchases made.