Animals ‘shapeshifting’ in response to climate crisis, research finds

Warm-blooded animals are changing beaks, legs and ears to adapt to hotter climate and better regulate temperature

The gang-gang cockatoo
The gang-gang cockatoo is one of the species whose bills have been increasing in size as the climate grows hotter. Photograph: William Robinson/Alamy

Helena HortonTue 7 Sep 2021 11.00 EDT

Animals are increasingly “shapeshifting” because of the climate crisis, researchers have said.

Warm-blooded animals are changing their physiology to adapt to a hotter climate, the scientists found. This includes getting larger beaks, legs and ears to better regulate their body temperature.

When animals overheat, birds use their beaks and mammals use their ears to disperse the warmth. Some creatures in warmer climates have historically evolved to have larger beaks or ears to get rid of heat more easily. These differences are becoming more pronounced as the climate warms.

If animals fail to control their body temperature, they can overheat and die. Beaks, which are not covered by feathers and therefore not insulated, are a site of significant heat exchange, as are ears, tails and legs in mammals if not covered by fur.

mulga parrot (Psephotus varius)
The beak of the mulga parrot (Psephotus varius) has been increasing in size. Photograph: Minden Pictures/Alamy

The review, published in the journal Trends in Ecology & Evolution, found that the differences are particularly pronounced in birds.Advertisement

The author of the study, Sara Ryding of Deakin university, a bird researcher, said: “Shapeshifting does not mean that animals are coping with climate change and that all is fine.

“It just means they are evolving to survive it – but we’re not sure what the other ecological consequences of these changes are, or indeed that all species are capable of changing and surviving.”

While the scientists say it is difficult to pinpoint climate breakdown as the sole cause of the shapeshifting, it is what the instances studied have in common across geographical regions and across a diverse array of species.

Examples include several species of Australian parrot that have shown a 4-10% increase in bill size since 1871, positively correlated with the summer temperature each year.

Meanwhile, research on the North American dark-eyed juncos, a type of small songbird, showed a link between increased bill size and short-term temperature extremes in cold environments.

Researchers have also reported tail length increases in wood mice, and tail and leg size increases in masked shrews. Bats in warm climates were shown to have increased wing size.

The paper argues that shapeshifting is likely to continue as the climate becomes warmer. It reads: “The increased temperatures associated with climate change are likely to influence, among other things, the thermoregulatory demands placed on animals.

“The increasing temperatures experienced as part of climate change may be selecting for larger appendages that facilitate efficient heat dissipation or result in relaxation of selection for small appendages through which body heat could be deleteriously lost in cold climates.”

The great round-leaf bat
The great round-leaf bat’s wings have been shown to be increasing in size. Photograph: Nature Picture Library/Alamy


Though the changes are small, Ryding said that could change as the planet became hotter.

“The increases in appendage size we see so far are quite small – less than 10% – so the changes are unlikely to be immediately noticeable,” she said. “However, prominent appendages such as ears are predicted to increase, so we might end up with a live-action Dumbo in the not-so-distant future.”

Ryding intends to investigate shapeshifting in Australian birds first-hand by 3D scanning museum bird specimens from the past 100 years to see which birds are changing appendage size due to climate change.

“A lot of the time when climate change is discussed in mainstream media, people are asking ‘can humans overcome this?’, or ‘what technology can solve this?’. It’s high time we recognised that animals also have to adapt to these changes, but this is occurring over a far shorter timescale than would have occurred through most of evolutionary time,” said Ryding.

A Rock Ptarmigan

“The climate change that we have created is heaping a whole lot of pressure on them, and while some species will adapt, others will not.”

It is unclear whether these changes will affect the animals in other ways – for example, bigger bills could affect how birds feed, something the scientists plan to research in future work.

Most Intense Burst of Evolution Ever Seen: Fossil Secret May Shed Light on Origins of Many of Earth’s First Animals

TOPICS:EvolutionGeographyPaleontologyUniversity Of Portsmouth


Drs. Minter and Bath Enright, of the University of Portsmouth’s School of the Environment, Geography and Geosciences, studied the Burgess Shale area of British Columbia, both on location in the field and with laboratory experiments. Credit: Dr. Orla Bath Enright

A large group of iconic fossils widely believed to shed light on the origins of many of Earth’s animals and the communities they lived in may be hiding a secret.

Scientists, led by two from the University of Portsmouth, UK, are the first to model how exceptionally well preserved fossils that record the largest and most intense burst of evolution ever seen could have been moved by mudflows.

The finding, published in Communications Earth & Environment, offers a cautionary note on how palaeontologists build a picture from the remains of the creatures they study.

Until now, it has been widely accepted the fossils buried in mudflows in the Burgess Shale in Canada that show the result of the Cambrian explosion 505 million years ago had all lived together but that’s now in doubt.

The Cambrian explosion was responsible for kick-starting the huge diversity of animal life now seen on the planet.

Now, Dr. Nic Minter and Dr. Orla Bath Enright have found that some of the animals which became fossils could have remained well preserved even after being carried large distances, throwing doubt on the idea the creatures all lived together.

Drs. Minter and Bath Enright, of the University of Portsmouth’s School of the Environment, Geography and Geosciences, studied the Burgess Shale area of British Columbia, both on location in the field and with laboratory experiments. Credit: Dr. Orla Bath Enright

Dr. Minter said: “This finding might surprise scientists or lead to them striking a more cautionary tone in how they interpret early marine ecosystems from half a billion years ago.

“It has been assumed that because the Burgess Shale fossils are so well preserved, they couldn’t have been transported over large distances. However, this new research shows that the general type of flow responsible for the deposits in which they were buried does not cause further damage to deceased animals. This means the fossils found in individual layers of sediment, and assumed to represent animal communities, could actually have been living far apart in distance.”

Drs Minter and Bath Enright, of the University of Portsmouth’s School of the Environment, Geography and Geosciences, studied the Burgess Shale area of British Columbia, both on location in the field and with laboratory experiments.

The site is an area rich in fossils entombed in the deposits of mudflows and is one of the world’s most important fossil sites, with more than 65,000 specimens already collected and, so far, more than 120 species counted.

The Burgess Shale area has been fundamental to scientists in understanding the origins of animal groups and the communities they lived among and has been closely studied multiple times.

The researchers, together with collaborators from the Universities of Southampton and Saskatchewan in Canada, used fieldwork to identify how the mudflows would have behaved, and then used flume tank laboratory tests to mimic the mudflows and are confident that the bodies of certain creatures could have been moved over tens of kilometers without damage, creating the illusion of animal communities which never existed.

The Burgess Shale was discovered in the early 1900s and led to the idea of the ‘Cambrian explosion’ of life, with the appearance of animals representing almost all the modern phyla, and inspiring copious research and discoveries.

Dr. Bath Enright said: “Many would argue that it is fundamental, even ground zero for scientists in understanding the diversity of life.”

It’s not known precisely what caused the mudflows which buried and moved the animals which became fossilized, but the area was subject to multiple flows, causing well-preserved fossils to be found at many different levels in the shale.

“We don’t know over what kind of overall time frame these many flows happened, but we know each one produced an ‘event bed’ that we see today stacked up on top of one another. These flows could pick up animals from multiple places as they moved across the seafloor and then dropped them all together in one place,” said Dr. Bath Enright.

“When we see multiple species accumulated together it can give the illusion we are seeing a single community. But we argue that an individual ‘event bed’ could be the product of several communities of animals being picked up from multiple places by a mudflow and then deposited together to give what looks like a much more complicated single community of animals.

“Palaeontologists need to appreciate the nature of the sediments that fossils are preserved within and what the implications of that are. We could be overestimating the complexity of early marine animal communities and therefore the patterns and drivers of evolution that have led to our present day diversity and complexity.”

The researchers hope to do further study to investigate whether differences in the species that are present in other fossil sites are due to evolutionary changes through time or the nature of the flows and the effects of transport and preservation of the fossils.

One incredible ocean crossing may have made human evolution possible


April 29, 2021 11.12am EDT


  1. Nicholas R. LongrichSenior Lecturer in Evolutionary Biology and Paleontology, University of Bath

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Humans evolved in Africa, along with chimpanzees, gorillas and monkeys. But primates themselves appear to have evolved elsewhere – likely in Asia – before colonising Africa. At the time, around 50 million years ago, Africa was an island isolated from the rest of the world by ocean – so how did primates get there?

A land bridge is the obvious explanation, but the geological evidence currently argues against it. Instead, we’re left with a far more unlikely scenario: early primates may have rafted to Africa, floating hundreds of miles across oceans on vegetation and debris.

Such oceanic dispersal was once seen as far-fetched and wildly speculative by many scientists. Some still support the land bridge theory, either disputing the geological evidence, or arguing that primate ancestors crossed into Africa long before the current fossil record suggests, before the continents broke up.

But there’s an emerging consensus that oceanic dispersal is far more common than once supposed. Plantsinsectsreptilesrodents and primates have all been found to colonise island continents in this way – including a remarkable Atlantic crossing that took monkeys from Africa to South America 35 million years ago. These events are incredibly rare but, given huge spans of time, such freak events inevitably influence evolution – including our own origins.

Primate origins

Humans appeared in southern Africa between 200,000350,000 years ago. We know we come from Africa because our genetic diversity is highest there, and there are lots of fossils of primitive humans there.

Our closest relatives, chimps and gorillas, are also native to Africa, alongside baboons and monkeys. But primates’ closest living relatives – flying lemurs, tree shrews and rodents – all inhabit Asia or, in the case of rodents, evolved there. Fossils provide somewhat conflicting evidence, but they also suggest primates arose outside of Africa.

Evolutionary tree showing primates and their geographic distributions
Primates have differentiated over tens of millions of years. Nicholas R. Longrich/Wikimedia

The oldest primate relative, Purgatoriuslived 65 million years ago, just after the dinosaurs disappeared. It’s from Montana.

The oldest true primates also occur outside Africa. Teilhardina, related to monkeys and apes, lived 55 million years ago, throughout Asia, North America, and Europe. Primates arrived in Africa later. Lemur-like fossils appear there 50 million years ago, and monkey-like fossils around 40 million years ago.

But Africa split from South America and became an island 100 million years ago, and only connected with Asia 20 million years ago. If primates colonised Africa during the 80 million years the continent spent isolated, then they needed to cross water.

A map of the world's continents 50 million years ago
The continents 50 million years ago, when primates colonised Africa. Deeptimemaps, Author provided (No reuse)

Ocean crossings

The idea of oceanic dispersal is central to the theory of evolution. Studying the Galapagos Islands, Darwin saw only a few tortoises, iguanas, snakes, and one small mammal, the rice rat. Further out to sea, on islands like Tahiti, were only little lizards.

Darwin reasoned that these patterns were hard to explain in terms of Creationism – in which case, similar species should exist everywhere – but they made sense if species crossed water to colonise islands, with fewer species surviving to colonise more distant islands.

He was right. Studies have found tortoises can survive weeks afloat without food or water – they probably bobbed along until hitting the Galapagos. And in 1995, iguanas swept offshore by hurricanes washed up 300km away, very much alive, after riding on debris. Galapagos iguanas likely travelled this way.

A tortoise covered in barnacles
Floating 800km from the Seychelles to Africa, this tortoise washed up on shore – covered in barnacles, but alive. Catharine Muir

The odds are against such crossings. A lucky combination of conditions – a large raft of vegetation, the right currents and winds, a viable population, a well-timed landfall – is needed for successful colonisation. Many animals swept offshore simply die of thirst or starvation before hitting islands. Most never make landfall; they disappear at sea, food for sharks. That’s why ocean islands, especially distant ones, have few species.

Rafting was once treated as an evolutionary novelty: a curious thing happening in obscure places like the Galapagos, but irrelevant to evolution on continents. But it’s since emerged that rafts of vegetation or floating islands – stands of trees swept out to sea – may actually explain many animal distributions across the world.


Several primate rafting events are well established. Today, Madagascar has a diverse lemur fauna. Lemurs arrived from Africa around 20 million years ago. Since Madagascar has been an island since the time of the dinosaurs, they apparently rafted the 400 kilometre-wide Mozambique Channel. Remarkably, fossils suggest the strange aye-aye crossed to Madagascar separately from the other lemurs.

Even more extraordinary is the existence of monkeys in South America: howlers, spider monkeys and marmosets. They arrived 35 million years ago, again from Africa. They had to cross the Atlantic – narrower then, but still 1,500 km wide. From South America, monkeys rafted again: to North America, then twice to the Caribbean.

Read more: Monkey teeth fossils hint several extinct species crossed the Atlantic

But before any of this could happen, rafting events would first need to bring primates to Africa: one brought the ancestor of lemurs, another carried the ancestor of monkeys, apes, and ourselves. It may seem implausible – and it’s still not entirely clear where they came from – but no other scenario fits the evidence.

A map of ocean crossings made by primates
Several primate rafting events are well established. R.Blakey/Wikimedia, Author provided (No reuse)

Rafting explains how rodents colonised Africa, then South America. Rafting likely explains how Afrotheria, the group containing elephants and aardvarks, got to Africa. Marsupials, evolving in North America, probably rafted to South America, then Antarctica, and finally Australia. Other oceanic crossings include mice to Australia, and tenrecsmongooses and hippos to Madagascar.

Oceanic crossings aren’t an evolutionary subplot; they’re central to the story. They explain the evolution of monkeys, elephants, kangaroos, rodents, lemurs – and us. And they show that evolution isn’t always driven by ordinary, everyday processes but also by bizarrely improbable events.


One of Darwin’s great insights was the idea that everyday events – small mutations, predation, competition – could slowly change species, given time. But over millions or billions of years, rare, low-probability, high-impact events – “black swan” events – also happen.

Read more: Black swans and other deviations: like evolution, all scientific theories are a work in progress

Some are immensely destructive, like asteroid impactsvolcanic eruptions, and ice ages – or viruses jumping hosts. But others are creative, like genome duplicationsgene transfer between multicellular species – and rafting.

The role rafting played in our history shows how much evolution comes down to chance. Had anything gone differently – the weather was bad, the seas rough, the raft washed up on a desert island, hungry predators waited on the beach, no males aboard – colonisation would have failed. No monkeys, no apes – no humans.

It seems our ancestors beat odds that make Powerball lotteries seem like a safe bet. Had anything had gone differently, the evolution of life might look rather different than it does. At a minimum, we wouldn’t be here to wonder about it.

How new discoveries in west Africa could rewrite pre-history

Tourists visit the ruins of Kunta Kinte island in the Gambia River, near Jufureh, Albreda
Archaeology in West Africa could rewrite the textbooks on human evolution.

By Eleanor Scerri

Independent Group Leader, Max Planck Institute for the Science of Human HistoryApril 17, 2021

Our species, Homo sapiens, rose in Africa some 300,000 years ago. The objects that early humans made and used, known as the Middle Stone Age material culture, are found throughout much of Africa and include a vast range of innovations.

Among them are bow and arrow technology, specialized tool forms, the long-distance transport of objects such as marine shells and obsidianpersonal ornamentation, the use of pigmentswater storage, and art. Although it is possible that other ancestors of modern humans contributed to this material culture in Africa, some of the earliest Middle Stone Age stone tools have been found with the oldest Homo sapiens fossils found so far.

The textbook view is that by around 40,000 years ago, the Middle Stone Age had largely ceased to exist in Africa. This was a milestone in the history of our species: the end of the first and longest lasting culture associated with humanity, and the foundation for all the subsequent innovations and material culture that defines us today.

Despite its central role in human history, we have little understanding of how the Middle Stone Age ended. Such an understanding could tell us how different groups were organized across the landscape, how they may have exchanged ideas and genes, and how these processes shaped the later stages of human evolution.

Unfortunately, vast swathes of Africa remain near complete blanks on the map when it comes to such deep prehistory, making it difficult to address these questions. Research has tended to focus on areas such as eastern Africa, where preservation is known to be high, understandably minimizing risks and maximizing gains. However, the emerging consensus that all of Africa played some role in human origins means that we can no longer afford to neglect vast regions of the continent if we want to reconstruct our evolution in a realistic framework.

For these reasons, my colleagues and I have been focusing on west Africa, one of the least well understood African regions for human evolution. And our recent work is validating earlier claims of a rich Middle Stone Age past.

New work in Senegal

In 2014, our work in Senegal led to the discovery of a site in the country’s north that suggested the Middle Stone Age ended there far more recently than the textbooks suggested. Several young dates in west Africa had been reported in the past, but the work was largely dismissed owing to problematic dating conducted before the present-day standards existed.

Dates from Ndiayène Pendao indicated that the site was around 12,000 years old. Yet the material culture was classically Middle Stone Age, without any Later Stone Age tools or production methods. In 2016 and 2018, we returned to the field to look for sites in different regions of Senegal and on different river systems, on tributaries of the Senegal and the Gambia. This is because sources of fresh water were critical to people in the past, just as they are to people today; river terraces also often offer excellent preservation conditions and are therefore good places to search for archaeological sites.

The site of Laminia on the Gambia had never been dated. We conducted a detailed assessment of its rock layers to obtain dating samples we could confidently link to the artifacts. The samples returned a date of 24,000 years ago for the site, which confirmed that a young Middle Stone Age was indeed present in the region.

The site of Saxomununya produced an even greater surprise. As the classically Middle Stone Age artifacts, such as retouched Levallois points, and ‘scrapers’, from this site were found upon and within a young terrace of the Falémé River, it was obvious that the site was relatively young. However, the date of 11,000 years ago took the youngest Middle Stone Age into the Holocene epoch, the period after the last major ice age. This was the first time such old material culture had been found in such recent times in Africa. It indicated that the results from Ndiayène Pendao were neither a fluke nor an error.

These results extend the last known occurrence of the Middle Stone Age by a staggering 20,000 years. At the same time, work by colleagues in Senegal also suggested an equally late first occurrence of the Later Stone Age at around 11,000 years—younger than in most other African regions.

Why did the Middle Stone Age last so long and why did the Later Stone Age arrive so late?

Population expansions

Part of the answer to the first question may lie in the fact that parts of west Africa appear to have been less affected by the extremes of repeated cycles of climate change. This may have created stable environmental conditions over a long period of time. As a result of such stability, a finely tuned toolkit that had worked well for millennia might not have needed to change, regardless of the social complexity of the people who made the tools.

The answer to the second question lies in the fact that this region of Africa was relatively isolated. To the north, it meets the Sahara Desert and to the east, there are the Central African rainforests, which were often cut off from the west African rainforests during periods of drought. However, around 15,000 years ago, there was a major increase in humidity and forest growth in central and western Africa. This may have linked different areas and provided corridors for dispersal of human populations. This may have spelled the end for humanity’s first and earliest cultural repertoire and initiated a new period of genetic and cultural mixing.

What is clear is that the long-held simple unilinear model of cultural change towards ‘modernity’ is not supported by the evidence. Groups of hunter-gatherers embedded in radically different technological traditions may have occupied neighboring regions of Africa for thousands of years, and sometimes shared the same regions. Long isolated regions, on the other hand, may have been important reservoirs of cultural and genetic diversity. This matches genetic studies and may have been a defining factor in the success of our species. Our findings are a reminder of the dangers of ignoring gaps on the map.

An Evolutionary Discovery That “Literally Changes the Textbook”

TOPICS:BioinformaticsEvolutionFishGeneticsMarine BiologyMichigan State University


Behold, the gar’s brain. In this microscope image, the brain’s left hemisphere fluoresces green and the right glows magenta. Yet, at the bottom of the image, nerves of both colors can be seen connecting to both hemispheres. This shows that both of the gar’s eyes are connected to both sides of its brain, like a human’s eyes are. Credit: Reprinted with permission from R.J. Vigouroux et al. Science 372:eabe7790 (2021)

MSU’s expertise in fish biology, genetics helping researchers rewrite evolutionary history and shape future health studies.

The network of nerves connecting our eyes to our brains is sophisticated and researchers have now shown that it evolved much earlier than previously thought, thanks to an unexpected source: the gar fish.

Michigan State University’s Ingo Braasch has helped an international research team show that this connection scheme was already present in ancient fish at least 450 million years ago. That makes it about 100 million years older than previously believed.

“It’s the first time for me that one of our publications literally changes the textbook that I am teaching with,” said Braasch, an assistant professor in the Department of Integrative Biology in the College of Natural Science.

The eyes of this spotted gar are connected to its brain in a way that’s both ancient and human-like. Credit: Courtesy of Ingo Braasch

This work, published online in the journal Science on April 8, 2021, also means that this type of eye-brain connection predates animals living on land. The existing theory had been that this connection first evolved in terrestrial creatures and, from there, carried on into humans where scientists believe it helps with our depth perception and 3D vision.

And this work, which was led by researchers at France’s Inserm public research organization, does more than reshape our understanding of the past. It also has implications for future health research.

Studying animal models is an invaluable way for researchers to learn about health and disease, but drawing connections to human conditions from these models can be challenging.

Zebrafish are a popular model animal, for example, but their eye-brain wiring is very distinct from a human’s. In fact, that helps explain why scientists thought the human connection first evolved in four-limbed terrestrial creatures, or tetrapods.

Ingo Braasch (center) poses in 2019 with members of his team, gar facility manager Brett Racicot (left) and postdoctoral associate Andrew Thompson (right), holding spotted gar grown at MSU. Credit: Courtesy Ingo Braasch

“Modern fish, they don’t have this type of eye-brain connection,” Braasch said. “That’s one of the reasons that people thought it was a new thing in tetrapods.”

Braasch is one of the world’s leading experts in a different type of fish known as gar. Gar have evolved more slowly than zebrafish, meaning gar are more similar to the last common ancestor shared by fish and humans. These similarities could make gar a powerful animal model for health studies, which is why Braasch and his team are working to better understand gar biology and genetics.

That, in turn, is why Inserm’s researchers sought out Braasch for this study.

“Without his help, this project wouldn’t have been possible,” said Alain Chédotal, director of research at Inserm and a group leader of the Vision Institute in Paris. “We did not have access to spotted gar, a fish that does not exist in Europe and occupies a key position in the tree of life.”

To do the study, Chédotal and his colleague, Filippo Del Bene, used a groundbreaking technique to see the nerves connecting eyes to brains in several different fish species. This included the well-studied zebrafish, but also rarer specimens such as Braasch’s gar and Australian lungfish provided by a collaborator at the University of Queensland.

In a zebrafish, each eye has one nerve connecting it to the opposite side of the fish’s brain. That is, one nerve connects the left eye to the brain’s right hemisphere and another nerve connects its right eye to the left side of its brain.

The other, more “ancient” fish do things differently. They have what’s called ipsilateral or bilateral visual projections. Here, each eye has two nerve connections, one going to either side of the brain, which is also what humans have.

Armed with an understanding of genetics and evolution, the team could look back in time to estimate when these bilateral projections first appeared. Looking forward, the team is excited to build on this work to better understand and explore the biology of visual systems.

“What we found in this study was just the tip of the iceberg,” Chédotal said. “It was highly motivating to see Ingo’s enthusiastic reaction and warm support when we presented him the first results. We can’t wait to continue the project with him.”

Both Braasch and Chédotal noted how powerful this study was thanks to a robust collaboration that allowed the team to examine so many different animals, which Braasch said is a growing trend in the field.

The study also reminded Braasch of another trend.

“We’re finding more and more that many things that we thought evolved relatively late are actually very old,” Braasch said, which actually makes him feel a little more connected to nature. “I learn something about myself when looking at these weird fish and understanding how old parts of our own bodies are. I’m excited to tell the story of eye evolution with a new twist this semester in our Comparative Anatomy class.”

Reference: “Bilateral visual projections exist in non-teleost bony fish and predate the emergence of tetrapods” by Robin J. Vigouroux, Karine Duroure, Juliette Vougny, Shahad Albadri, Peter Kozulin, Eloisa Herrera, Kim Nguyen-Ba-Charvet, Ingo Braasch, Rodrigo Suárez, Filippo Del Bene and Alain Chédotal, 9 April 2021, Science.
DOI: 10.1126/science.abe7790

Crocodiles survived dinosaur-killing asteroid due to snappy evolution

Shivali Best For Mailonline  16 hrs ago

TV Presenter Attacked by Naked Woman Live on AirFlorida woman missing for weeks found trapped, naked in storm draina close up of a reptile: MailOnline logo© Provided by Daily Mail MailOnline logo

It’s a mystery that has baffled scientists for years – why did crocodiles survive the asteroid strike that wiped out the dinosaurs 66 million years ago?

Now, researchers believe they may have the answer, and it all comes down to aptly named ‘snappy evolution.’

In a new study, scientists suggest that crocodiles underwent rapid evolution that meant the creatures could flourish on land and in the oceans.

Dr Stephanie Pierce, Associate Professor of Organismic and Evolution Biology at Harvard University, said: ‘Ancient crocodiles came in a dizzyingly array of forms. They were adapted to running on land, swimming in the water, snapping fish, and even chewing plants.

‘Our study shows that these very different ways of living evolved incredibly fast, allowing extinct crocodiles to rapidly thrive and dominate novel ecological niches over many millions of years.’a close up of a reptile: In a new study, scientists suggest that crocodiles underwent rapid evolution that meant the creatures could flourish on land and in the oceans. Pictured is a modern crocodile© Provided by Daily Mail In a new study, scientists suggest that crocodiles underwent rapid evolution that meant the creatures could flourish on land and in the oceans. Pictured is a modern crocodile

In the study, researchers from the University of Bristol and Harvard University studied over 200 skulls and jaws of crocodiles and their extinct species, spanning 230 million years.

The team analysed how the shape of the skulls and jaws varied between species, and studied how fast crocodile groups changed with time.

Their findings suggest that some extinct crocodile groups, including dolphin-like thalattosuchians and land-dwelling notosuchians, evolved very fast over millions of year.

These species also underwent huge changes to their skulls and jaws, becoming almost mammal-like at times.

And while today’s crocodiles, alligators and gharials are often referred to as ‘living fossil’, the researchers suggest that this isn’t the case, and that there is ‘no evidence for a slow-down in their evolution.’

Instead, the team believes that today’s crocodiles, alligators and gharials evolved steadily for the last 80 million years.

Dr Tom Stubbs, who led the study, said: ‘Crocodiles and their ancestors are an incredible group for understanding the rise and fall of biodiversity.A fossil of a land-dwelling crocodile from the Cretaceous. Notosuchians had diverse diets, including insect-eating and plant-eating© Provided by Daily Mail A fossil of a land-dwelling crocodile from the Cretaceous. Notosuchians had diverse diets, including insect-eating and plant-eatingThis tiny skull belonged to an early ancestor of crocodiles which lived on land and had a diverse diet© Provided by Daily Mail This tiny skull belonged to an early ancestor of crocodiles which lived on land and had a diverse diet

‘There are only 26 crocodile species around today, most of which look very similar. However, there are hundreds of fossil species with spectacular variation, particularly in their feeding apparatus.’

While scientists have long believed that dramatic shifts in habitat and diet can trigger rapid evolution, this is the first time it has been shown in crocodiles.

Professor Micahel Benton, who also worked on the study, said: ‘It’s not clear why modern crocodiles are so limited in their adaptations. a wooden table: While scientists have long believed that dramatic shifts in habitat and diet can trigger rapid evolution, this is the first time it has been shown in crocodiles. Pictured is an extinct ocean-going crocodile from the Jurassic© Provided by Daily Mail While scientists have long believed that dramatic shifts in habitat and diet can trigger rapid evolution, this is the first time it has been shown in crocodiles. Pictured is an extinct ocean-going crocodile from the Jurassic

‘If we only had the living species, we might argue they are limited in their modes of life by being cold-blooded or because of their anatomy.

‘However, the fossil record shows their amazing capabilities, including large numbers of species in the oceans and on land. 

‘Perhaps they only did well when world climates were warmer than today.’Read moreContinue Reading Crocodiles survived dinosaur-killing asteroid due to snappy evolution (

How Ancient ‘Deer’ Lost Their Legs and Became Whales

Over millions of years, they traded in their legs for flippers, gained blow holes and evolved into the largest creatures on Earth.

By Joshua Rapp LearnMarch 19, 2021 6:00 AM

Humpback whale

(Credit: Imagine Earth Photography/Shutterstock)


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The largest animals that have ever existed on our planet descended from a miniature deer-like creature that walked on four legs in the swamps of ancient India.

Cetaceans include everything from dolphins to whales. They are fairly unique among mammals in that they live permanently in the sea — something they share with only a few other types of live-bearing, warm-blooded species.

But their evolutionary ancestors weren’t always the seafaring types. In fact, just 50 million years ago, ancestors of all cetaceans were small creatures called Indohyus that waded through swamps on four legs.about:blankabout:blank

Indohyus basically looked like a tiny little deer, a deer the size of a cat,” says Hans Thewissen, a professor at Northeast Ohio Medical University who has studied whale evolution for years and wrote the book The Walking Whales: From Land to Water in Eight Million Years.

How did these creatures go from that to blue whales the length of about two city buses? It took a lot of small changes over tens of millions of years.

The Land of Indohyus

Indohyus belonged to the even-toed group of ungulates, which today includes giraffes, horses, pigs and cetaceans. Research shows that back in the Eocene epoch roughly 50 million years ago, Indohyus lived in modern-day India and Pakistan. Today, a distant deer-like relative called the water chevrotain (or African mouse-deer) can be found from central to southern Africa. These deer eat flowers and fruitsand live near rivers, which they use as escape routes to flee land-based predators or even eagles.

Thewissen’s research examining stable isotopes in Indohyus fossils shows they ate land plants, but their dense bones suggest they spent a lot of time in the water. The hippopotamus — the closest living relative of whales that live outside the ocean — also has dense bones, which help weigh it down while walking along the bottom of lakes or rivers.

A Taste for Meat

The evolutionary descendant of Indohyus, called Pakicetus, began to adopt a more aquatic lifestyle as they abandoned a vegetarian diet, based on the way their teeth look, Thewissen says. These creatures looked a little like wolves with elongated bodies, and also lived in the India-Pakistan region. Remaining fossils of these extinct animals have only been found in rocks, which tells us that they likely spent a lot of time in shallow pools of water.about:blankabout:blank

“We think they sat in the water and waited for prey to drink, similar to crocodiles,” Thewissen says.

These animals were succeeded byambulocetids, at which point the creatures’ snouts becomes more elongated like crocodiles. All four limbs also shortened in these creatures. “They were much better swimmers,” Thewissen says. “[Their fossils] are found in rocks indicative of coastal environment.”

By the time remingtonocetids appeared between 49 million and 42 million years ago, the animal family began to diversify. Thewissen describes some of these animals with bodies like giant otters while others had long, thin snouts a little like gharials today, which they likely used to snap fish out of the water.

“This is a phase of experimentation where different species are trying different ways of living and modifying their bodies to match,” Thewissen says.

Some of their fossil fragments are found outside of the India-Pakistan region, which shows remingtonocetids may have been able to swim long distances, Thewissen adds.

The Life Aquatic

The first ancestors of whales that began to take to the ocean more widely were the protocetids from 48 million to 42 million years ago, based partly on the fact that these fossils are found across the world from Pakistan to the eastern U.S. and Peru. Thewissen describes them as looking a little more like sea lions, with limbs big enough to support them on land, though he notes that researchers still don’t know the full range of body shapes that occurred with these prehistoric animals.

In any case, the general shapes change a lot in the next stage, that of the basilosaurids, so called in part because the first paleontologists to find some of the creatures believed they were some sort of sea snake. In reality, Thewissen says these are the first creatures “we would actually recognize as whales.”

There were two major shapes of basilosaurids. The giant sea snake-looking ones, such as the Basilosaurus isis, were about as long as a bus and still had tiny hind legs and front forearms that gave way to flippers. The other group, the dorudontines, appeared a little like dolphins, with flippers and no neck but tiny hind legs. They also had a fluke appearing at the end of their tails, characteristic of today’s cetaceans. It’s possible that the flukes started earlier, with some protocetids.

“They shortened their thumb and elongated their other fingers through time,” says Rachel Racicot, a researcher who studies cetacean evolution at the Senckenberg Research Institute and Natural History Museum in Frankfurt, Germany.

Though blow hole development likely started with the protocetids, it really became apparent in the basilosaurids. They began to form streamlined heads with noses more useful for coming up for air. “They start to have their nose closer to the back of their heads to make it easier to breathe,” Racicot says.

These creatures went extinct between 42 million and 34 million years ago — roughly the time the ancestors of modern cetaceans began to appear. The descendants of basilosaurids lost their hind legs completely and split into the two groups of whales we know today: baleen whales and toothed whales.

Baleen whales emerged as the earliest whale group about 41 million years ago. These first whales included the ancestors of species like bowheads, humpbacks, right whales and blue whales. Toothed whales started to appear about 34 million years ago with the ancestors of orcas, dolphins, porpoises, sperm whales, belugas and beaked whales, though the oldest whale species still around today have only been around for roughly 10 million years, and most species are only a few million years old.

The major difference between baleen and toothed whales is their feeding strategy. The toothed whales hunt down prey and eat it, often using echolocation. Baleen whales are still carnivorous, but they specialize in grazing on tiny creatures like krill in vast numbers, filtering them through their grill-like baleen as they swim.

As these two groups began to emerge from their basilosaurid ancestors, they also started to develop another key component that sets cetaceans apart from many mammals — their smarts. “We see a real jump in brain size happening in the Eocene,” Thewissen says.

While modern research on whale intelligence is expanding, it has also revealed that many mysteries remain concerning these giants of the deep.

Humans Share Genes With Weird Headless Creatures

Tim Childers  6 hrs ago

New cross-country storm to bring more severe weatherFans Are Calling Out Khloé Kardashian’s Photoshopping in New Bikini PictureResearchers traced genes found in humans back to some of the earliest multicellular animals to roam Earth.© Evans, et. al./Proceedings of the Royal Society B/Courtesy Christine Hall Researchers traced genes found in humans back to some of the earliest multicellular animals to roam Earth.

  • Researchers traced genes found in humans back to some of the earliest multicellular animals to roam Earth.
  • The 555-million-year old fossils belong to oceanic creatures that predate the Cambrian explosion.
  • The animals may be the missing link between the first complex life forms on Earth and humans.

Peer back far enough into the fossil record and the evolutionary links between modern animals and ancient creatures become increasingly unclear. Although some of Earth’s first organisms lacked now-common features like heads, arms, and legs, researchers have traced back genes found in today’s animals—including humans—to some of the oldest complex multicellular creatures.

➡ Science is bad***. Let’s nerd out over it together.

Their research, published in the journal Proceedings of the Royal Society B, uses genetic analysis to link the appearance of 555-million-year-old fossils of simple oceanic critters to the genes found in complex modern-day animals. These findings could help biologists understand the evolution of the first animals on Earth during one of the most critical periods of the planet’s history.

The Cambrian explosion has long been considered the“big bang” of the evolution of life on Earth. During this period, beginning more than half a billion years ago, almost every major animal group inhabiting the planet today appeared in the fossil record over the span of a few million years.

But recent discoveries are leading scientists to believe the Ediacaran era, a brief period beginning 40 million years before the Cambrian explosion, may have been just as pivotal in the history of evolution. The Ediacaran period is marked by the emergence of the earliest known complex multicellular organisms on Earth. It’s also when scientists believe some of the defining characteristics of animals first took form.

“None of them had heads or skeletons,” study coauthor Mary Droser, Ph.D., a geology professor at the University of California, Riverside, said in a statement. She continued:

“Many of them probably looked like three-dimensional bath mats on the seafloor, round discs that stuck up. These animals are so weird and so different, it’s difficult to assign them to modern categories of living organisms just by looking at them, and it’s not like we can extract their DNA—we can’t.”

Lacking concrete DNA evidence, the researchers examined the appearance and likely behaviors of the animals that are clearly represented by genetic markers in modern animals. These markers include genes like SoxB2, which is believed to play a key role in the formation of an animal’s nervous system.

“The fact that we can say these genes were operating in something that’s been extinct for half a billion years is fascinating to me,” said study coauthor Scott Evans, Ph.D., a professor in the department of geosciences at Virginia Tech.

From more than 40 species identified from the Ediacaran period, the researchers picked four animals to study closely.(a,b) Kimberella quadrata (K) with frill or muscular foot (MF), proboscis (P) and associated scratch marks (SM); (c,d) Ikaria wariootia with wider end indicated by white stars and with associated trace fossil Helminthoidichnites; (e) Dickinsonia costata with white arrow indicating the direction of movement; and (f) Tribrachidium heraldicum.© Evans, et. al./Proceedings of the Royal Society B/Courtesy Christine Hall (a,bKimberella quadrata (K) with frill or muscular foot (MF), proboscis (P) and associated scratch marks (SM); (c,dIkaria wariootia with wider end indicated by white stars and with associated trace fossil Helminthoidichnites; (eDickinsonia costata with white arrow indicating the direction of movement; and (fTribrachidium heraldicum.

The most iconic and largest of the bunch, the oval-shaped Dickinsonia, has been found to grow to almost a meter in length with a series of raised bands on its surface. Recently, scientists discovered Dickinsonia may have been capable of repairing itself from damage, showing the possibility of it having a primitive immune system.

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The smallest critter, Ikaria, which Droser and her colleagues recently discovered, was about the size and shape of a grain of rice. It’s also one of the oldest bilaterians—an animal with two front and back openings connected by a gut—ever found. Scientists believe Ikaria was one of nature’s first scavengers, crawling using primitive muscles across the sea floor and eating organic matter.

The researchers also analyzed a teardrop-shaped animal called Kimberella, which may have scraped the ocean floor for food using a proboscis. Lastly, they studied Tribrachidium, a living ninja-star that the scientists, using computationational fluid mechanics simulations, believe used gravity to filter out particles of food falling into its spiral trap.

“Our work is a way to put these animals on the tree of life, in some respects,” Droser said.“And show they’re genetically linked to modern animals, and to us.”

Given their complexity, the researchers believe the animals likely had the genetic building blocks responsible for the formation of heads and sensory organs that could form a central nervous system. This includes genes like Hox, which are responsible for specifying the organization of parts of the body during development. However, the interaction between those building blocks wasn’t yet complex enough to create the concentrated nervous systems found in Cambrian-period animals.

In the future, the scientists hope to examine muscle development and perform functional studies to better understand this ancient period of animal evolution.

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Continued: Humans Share Genes With Weird Headless Creatures (

‘Pompeii of prehistoric plants’ unlocks evolutionary secret: study

MARCH 8, 2021

by University of Birmingham

'Pompeii of prehistoric plants' unlocks evolutionary secret: study
Reconstruction of the crown of Paratingia wuhaia sp. nov. Credit: University of Birmingham

Spectacular fossil plants preserved within a volcanic ash fall in China have shed light on an evolutionary race 300 million years ago, which was eventually won by the seed-bearing plants that dominate so much of the Earth today.

New research into fossils found at the ‘Pompeii of prehistoric plants‘, in Wuda, Inner Mongolia, reveals that the plants, called Noeggerathiales, were highly-evolved members of the lineage from which came seed plants.

Noeggerathiales were important peat-forming plants that lived around 325 to 251 million years ago. Understanding their relationships to other plant groups has been limited by poorly preserved examples until now.

The fossils found in China have allowed experts to work out that Noeggerathiales are more closely related to seed plants than to other fern groups.

No longer considered an evolutionary dead-end, they are now recognized as advanced tree-ferns that evolved complex cone-like structures from modified leaves. Despite their sophistication, Noeggerathiales fell victim to the profound environmental and climate changes of 251 million years ago that destroyed swamp ecosystems globally.

The international research team, led by palaeontologists at Nanjing Institute of Geology and Palaeontology and the University of Birmingham, today published its findings in the Proceedings of the National Academy of Sciences (PNAS).

'Pompeii of prehistoric plants' unlocks evolutionary secret: study
This reconstruction is based on the type specimen from the Wuda Tuff Flora and shows what scientist think the plant looked like when it was alive. Reconstruction of the peat-forming plant community at Wuda in which the new species Paratingia wuhaia (yellow arrows) grew. Credit: University of Birmingham

Co-author Dr. Jason Hilton, Reader in Palaeobiology at the University of Birmingham’s Institute of Forest Research, commented: “Noeggerathiales were recognized as early as the 1930s, but scientists have treated them as a ‘taxonomic football’, endlessly kicked around without anyone identifying their place in the Story of Life.

“The spectacular fossil plants found in China are becoming renowned as the plant equivalent of Pompeii. Thanks to this slice of life preserved in volcanic ash, we were able to reconstruct a new species of Noeggerathiales that finally settles the group’s affinity and evolutionary importance.

“The fate of the Noeggerathiales is a stark reminder of what can happen when even very advanced life forms are faced with rapid environmental change.”×280&!1&btvi=1&fsb=1&xpc=cKoMtQYfNY&p=https%3A//

The researchers studied complete Noeggerathiales preserved in a bed of volcanic ash 66 cm thick formed 298 million years ago, smothering all the plants growing in a nearby swamp.

The ash stopped the fossils from rotting or being consumed, and preserved many complete individuals in microscopic detail.

'Pompeii of prehistoric plants' unlocks evolutionary secret: study
Fossil specimen of the new species preserving the crown of the tree with leaves and its fertile organs attached to the stem. Credit: University of Birmingham

Lead-Author Jun Wang, Professor of Palaeobotany at Nanjing Institute of Geology and Palaeontology, commented: “Many specimens were identified in excavations in 2006-2007 when a few leaves were visible on the surface of the ash. It looked they might be connected to each other and a stem below—we revealed the crown on site, but then extracted the specimens complete to take them back to the lab.

“It has taken many years to study these fully and the additional specimens we have found more recently. The complete trees are the most impressive fossil plants I have seen and because of our careful work they are also some of the most important to science.”

The researchers also deduced that that the ancestral lineage from which seed plants evolved diversified alongside the earliest seed plant radiation during the Devonian, Carboniferous and Permian periods, and did not rapidly die out as previously thought.

Million-Year-Old DNA Rewrites Mammoths’ Evolutionary Tree

02.21.2021 09:00 AM

The oldest DNA ever sequenced shows how the genus split off into new species.

mammoth tusk

ANCIENT DNA HAS revolutionized how we understand human evolution, revealing how populations moved and interacted and introducing us to relatives like the Denisovans, a “ghost lineage” that we wouldn’t realize existed if it weren’t for discovering their DNA. But humans aren’t the only ones who have left DNA behind in their bones, and the same analyses that worked for humans can work for any other group of species.ARS TECHNICA

This story originally appeared on Ars Technica, a trusted source for technology news, tech policy analysis, reviews, and more. Ars is owned by WIRED’s parent company, Condé Nast.

Today, the mammoths take their turn in the spotlight, helped by what appears to be the oldest DNA ever sequenced. DNA from three ancient molars, one likely to be over a million years old, has revealed that there is a ghost lineage of mammoths that interbred with distant relatives to produce the North American mammoth population.ADVERTISEMENT

Mammoths share something with humans: Like us, they started as an African population but spread across much of the planet. Having spread out much earlier, mammoth populations spent enough time separated from each other to form different species. After branching off from elephants, the mammoths first split into what are called southern and steppe species. Later still, adaptations to ice age climates produced the woolly mammoth and its close relative, the North American mammoth, called the Columbian mammoth. All of those species, however, are extinct, and the only living relatives are the elephants.

We have obtained DNA from two of these species, the woolly and Columbian mammoths. These revealed both a number of adaptations to cold climates and a small degree of interbreeding, as woolly mammoths made their way into North America and contributed a small amount (about 10 percent) to the genome of the Columbia population.

The new work focused on mammoth teeth found in Siberia, where conditions have favored both the preservation of remains and the preservation of the DNA they contain. The teeth come from layers of material that appear to have been deposited at the start of the most recent glacial period, which is when the ancestors of the woolly mammoth population should have been present in the area.

We don’t have precise dates for any of the teeth, as they appear to be too old for carbon dating. Instead, dates have been inferred using a combination of the species present in the deposits and the known timing of flips in the orientation of Earth’s magnetic field. In addition, the shape of the teeth provides some hints about what species they group with and some further indication of when they were deposited. In all, one tooth is likely to be at least 500,000 years old, another about a million years old, and a third somewhat older still.

Previously, the oldest DNA obtained from animal remains is roughly the age of the youngest of these samples. But the researchers were able to recover some elephant-like DNA from each of the molars, although it was badly fragmented, and many individual bases were damaged. Researchers were able to isolate the full mitochondrial genome for each of the three teeth, as each cell contains many copies of this genome in each of its mitochondria. Only fragments of the nuclear genome could be obtained, however—at most, about 10 percent of one genome, and at worst under 2 percent. (Less than 2 percent is still tens of millions of individual bases.)

Using the differences between the mammoth and elephant DNA and assuming a constant rate of mutation, the research team was able to derive independent dates for when each of the animals that left a tooth must have lived. Based on the mitochondria genome, the dates were 1.6 million, 1.3 million, and 900,000 years ago. For the two that had enough nuclear genome to analyze, the dates were 1.3 million and 600,000 years ago. The DNA-based dates for these two lined up nicely with each other and the date of the material they were found in. The oldest sample might be older than the deposit it’s in, and thus it might have been moved after death.

While these dates are fairly uncertain, they pretty clearly place two of the samples as the oldest DNA ever obtained from animals. And it would mean that these mammoths were living in Siberia shortly after ice-age conditions prevailed, although before there was a clear woolly mammoth lineage. They’d also predate the known appearance of mammoths in North America. Popular


For all these reasons, the genomes potentially have a lot to say about the history of mammoths.

And they do. The two younger samples are clearly on the same lineage that eventually produced the woolly mammoth, although they obviously predate the more recent samples that have yielded more complete genomes. But the oldest, from a site called Krestovka, looks like it’s from a separate lineage entirely. While it’s related to the woolly mammoth branch, it clearly diverged from it, and the analysis suggests that the split occurred at least 1.8 million years ago.

Krestovka also doesn’t have any direct modern descendants, indicating that it may have died off as a distinct population. But a lot of its DNA carried on as part of the Columbia mammoth genome. Apparently, at some point after the Krestovka, the lineage it was on interbred with the ancestors of the woolly mammoths. The result was a nearly 50/50 mix of the genomes of the two branches, the descendants of which migrated into North America and formed the Columbia mammoth population. Only much later did it meet the descendants, now a distinct woolly mammoth population, when they crossed into North America.

These animals were also already nearly as well adapted to the cold as their descendants, the woolly mammoths. The researchers identified 5,600 cases where the proteins of the mammoth genome differed from those in elephants. The ancient mammoths had already picked up over 85 percent of these changes, including ones involved in hair growth, fat deposits, temperature sensing, and handling of day/night cycles.

In other words, these things probably looked a lot like woolly mammoths, even if they were from a population that was still part of a larger cluster of mammoth ancestors living in Siberia at the time.

Mammoths may provide a relatively rare case, as we have a lot of their remains, and they lived in a part of the world where conditions are excellent for preserving DNA. But they also likely had a long generation time, so they underwent population changes at a far more gradual pace than many other species.

Even though getting DNA this old is rare, we might not need ancient DNA to get valuable information on how the species around us came into existence. And based on us and the mammoths, digging into these histories may provide lots of surprises.

Nature, 2021. DOI: 10.1038/s41586-021-03224-9  (About DOIs).

This story originally appeared on Ars Technica.