Tag Archives: paleontology

Balkanatolia: the forgotten ancient battleground where mammals fought for supremacy in Europe

Map showing Balkanatolia 40 million years ago and at the present day. Credit: Alexis Licht & Grégoire Métais.

For millions of years, Western Europe’s megafauna was literally worlds apart from that in Asia, owed to impenetrable natural barriers that allowed species on both continents to evolve and diverge. But that all changed in the blink of an eye, geologically speaking, after the more robust and adaptable Asian mammals poured into Europe, where they quickly replaced the endemic fauna. How exactly this event, known as the Grande Coupure, panned out has always been a mystery, but a new study is filling the gaps in our knowledge by proposing an interesting hypothesis: the Asian mammals invaded through an ancient landmass called Balkanatolia.

If the name Balkanatolia rings a bell, it’s because it refers to the present-day regions of the Balkans and Anatolia, which 50 million years ago formed an isolated archipelago, separate from the neighboring continents of Europe, Africa, and Asia. The name Balkanatolia was recently given by researchers at the French National Center for Scientific Research in a new study that highlights the biogeographic province’s major role in the Grande Coupure, which occurred some 34 million years ago.

That’s because examinations of previous fossils found in both the Balkan peninsula and Anatalonia — some of which date as far back as the 19th-century– performed by the researchers led by paleogeologist Alexis Licht showed that Asian mammals started colonizing southern Europe as early as 5 to 10 million years prior to the Grande Coupure.

In a subsequent review of this fossil record, the researchers uncovered patterns that allowed them to reconstruct the biogeographic history of the region over the span of millions of years.

The researchers found that for much of the Eocene Epoch (55 to 34 million years ago), the Balkans and Anatolia harbored homogeneous terrestrial fauna, which was distinct from that in continental Europe and Asia. Some of these mammals included marsupials of South American origin and large herbivorous mammals resembling hippos, known as Embrithopoda. The presence of these distinct animals just makes sense for an isolated archipelago, which is why the researchers proposed the existence of Balkanatolia.

However, Balkanatolia would soon be greeted by some uninvited guests. New fossil deposits from Büyükteflek in Turkey, dated to 38 to 35 million years ago, clearly belonged to mammals with an Asian lineage — the earliest of their kind discovered in Anatolia until now. These include fossils belonging to Brontotheres, huge animals resembling large rhinoceroses that died out at the end of the Eocene.

From this amalgam of fossils from different eras, the researchers pieced together a story: Balkanatolia comprised a single landmass isolated from the rest of the continents beginning with 50 million years ago, but would be colonized some 40 million years ago by Asian mammals. How exactly these animals reached the archipelago is not understood, but it seems like the region became a stepping stone for the Asian mammal invasion. The straight Eurasian route through modern-day Russia was not a viable route due to the huge glaciers and other geographical obstacles.

It is likely that a major glaciation event, which lowered sea levels some 34 million years ago, formed a bridge between Balkanatolia to Western Europe, releasing the floodgates of invasive Asian species. In no time, Western Europe endemic animals like Palaeotheres, an extinct group distantly related to present-day horses, but more like today’s tapirs, became extinct and were replaced by more diverse and resilient fauna including mammal families found today on both continents.

In other words, these findings suggest that the Grande Coupure was actually a two-stage event. In the first event, Asian mammals colonized Balkanatolia, where they replaced much of the existing fauna. Then, taking advantage of shifting geographical conditions due to climate change, the invasive species continued their conquest in the rest of the European continent.

“This colonization event was facilitated by a drop in global eustatic sea level and a tectonically-driven sea retreat in eastern Anatolia and the Lesser Caucasus during the late middle Eocene. These paleogeographic changes instigated the demise of Balkanatolia as a distinct biogeographic province and paved the way for the dispersal of Asian endemic clades before and during the Grande Coupure in western Europe,” the authors wrote in their study published in Earth-Science Reviews.

Fossil Friday: ancient whale that walked on all fours found deep in the Egyptian desert

Roughly one decade ago, Egyptian environmentalists uncovered the bones of an ancient whale — in the sands of the Western Desert. Now, a new paper details this strange finding, describing a brand new species of ‘semi-aquatic’ whale ancestor.

The holotype (the specimen from which the species was described and named) of Phiomicetus anubis. Image credits Abdullah S. Gohan et al., (2021), Proc. R. Soc. B.

This four-legged whale ancestor lived around 43 million years ago, and was, by all indications, an accomplished hunter.

Grandma whale

“We chose the name Anubis because it had a strong and deadly bite,” said paleontologist Hesham Sallam, professor of paleontology at Mansoura University in Egypt, who led the research effort. “It could kill any creature it crossed paths with.”

Phiomicetus anubis is a key new whale species, and a critical discovery for Egyptian and African palaeontology,” the study’s lead author, Abdullah Gohar, told Reuters news agency.

The whale is part of the extinct Phiomicetus genus of protocetidae whales — essentially, the family from which modern whales emerged. It was given the name Anubis in honor of the ancient Egyptian god of death, as judging from its fossils, the animal was quite an accomplished killer.

The animal’s elongated snout and skull point to it being a capable carnivore both in regards to grasping prey and chewing through tough hides and bones.

Perhaps its most unusual features, for most people, would be that P. anubis was semi-aquatic, and possessed four stout legs instead of flippers. The area that makes up the Western Desert today used to be a sea 43 million years ago. P. anubis hunted in its waters and, likely, walked around its shores.

The fossil was first found in 2008, but Sallam put off investigating it until 2017, as he worked to assemble a team of paleontologists that would do the fossil justice. Their work culminated last month when they officially confirmed that the fossil belongs to a completely new species.

From a paleontological standpoint, the discovery is particularly exciting as P. Anubis is one of the last known members of the whale family that retained functional, land-going limbs. Whales as a family have evolved from land mammals that returned to the sea, also transitioning from a herbivorous to a carnivorous diet in the process. Today, all members of the whale family (cetaceans) live exclusively in the seas and oceans. Thus, they have quite an interesting story to tell.

P. anubis was a species that emerged during that transition period, making it a valuable source of information on how it took place and when. Fossils from this window of the whales’ evolutionary history are particularly valuable for helping us understand when they finally made the full transition to ocean life, and where. Currently, our best indication is that it took place around 50 million years ago in today’s India or Pakistan, but this is by no means a settled topic. The new species will undoubtedly help flesh out our understanding of this timeline.

Surprisingly for a desert, Egypt’s Western Desert is quite famous for its prehistoric whale fossils. One area in particular, the White Valley of Wadi al-Hitan, has been declared a natural World Heritage site and attracts a lot of tourist attention due to its prehistoric whale fossils.

The paper “A new protocetid whale offers clues to biogeography and feeding ecology in early cetacean evolution” has been published in the journal Proceedings of the Royal Society B: Biological Sciences.

Fossil-ish Friday: Mary Anning’s work to be commemorated on 50 pence coins

The UK will be celebrating one of the people who made paleontology go from a hobby to a science, Marry Anning, on a series of 50p coins. These will feature Jurassic dinosaurs that she discovered, and the first one released features the temnodontosaurus, which a 12-year-old Anning discovered with her brother in 1810.

Image credits Royal Mint.

We were born into everything the modern world has to offer, so we can be forgiven if we take them for granted. But there was a time, not even that long ago, when this world had to be built piece by piece. A great part of that effort involved understanding the planet we live on and its rules, so that we may bend them to our benefit.

Mary Anning was an integral part of that. She was born into a poor family on the southern shore of England and her father would often look for fossils on the shore. These could be sold to wealthy collectors for just enough money to scrape by. After his passing, Mary Anning took up the trade. She would become the first person to discover the fossilized remains of an ichthyosaur and later a plesiosaur, both sea-dwelling dinosaurs. In many ways, she is regarded as the mother of modern paleontology.

Put her on a coin!

“The Mary Anning collection celebrates a pivotal figure in the understanding of palaeontology, important contributions to science that were rarely acknowledged in Mary’s lifetime,” says Clare Matterson, the executive director of engagement at the Natural History Museum, which is involved in the project. “It is fantastic to see Mary celebrated in such a special way in 2021.”

The coins will feature some of the most terrifying Jurassic sea creatures as a celebration of Mary Anning’s work. They’re the latest in a string of gestures meant to commemorate her contributions to science. For example, the Natural History Museum in London named a suite of rooms after her in 2018, her story was told in the movie Ammonite, and she was almost put on the UK’s upcoming new £50 note (although she eventually lost to Alan Turing).

This is the second set of coins in the Tales of the Earth series, a collaboration between the Natural History Museum and the Royal Mint. The first series revolved around more traditional dinosaurs. This one will feature the Jurassic sea-faring animals discovered by Anning. One already-released coin features the temnodontosaurus, one of the largest species of ichthyosaur. It was the species that Mary discovered with her brother in 1810, and could grow up to 10 meters long. It also had the distinction of sporting the largest eye we’ve ever found, each around the size of a soccer ball.

Other coins in the series will feature the plesiosaurus and the dimorphodon, a species of flying dino.

The coins are priced from £10 to £1,100 and have been designed by Robert Nicholls, a natural history artist, with guidance from Sandra Chapman, one of the experts at the museum. Each carries “a scientifically accurate reconstruction of the creatures and the environment that they existed in”, according to the Royal Mint.

Mammoth remains possibly butchered by human hunters found on Arctic Island near Siberia

Part of the mammoth skeleton found by the Russian researchers. Credit:  I.S. Pavlov.

Russian paleontologists were stunned by the discovery of an almost complete mammoth skeleton on Kotelny Island, located in the Arctic close to the Siberian coast, which had thousands of cut marks on it. These marks, as well as stone objects embedded within some of the fossils, indicate that the ancient beast might have been slain and butchered by human hunters.

The extraordinary mammoth skeleton came to the attention of Russian researchers completely by accident. In 2019, Innokenty Pavlov, a field worker and taxidermist, was on an expedition in the north of Kotelny Island —  part of the New Siberian Islands in the eastern Arctic and home to a major Russian military base — to dig up the carcass of another known mammoth in the area. However, the melting snow flooded the site of the carcass, making excavations impossible. But as luck had it, they were informed by local fishermen that there was another mammoth site, just 10 kilometers away.

Indeed, the site proved to be genuine, and it is here that Pavlov, along with researchers led by Albert Protopopov, head of the Department for Study of Mammoth Fauna, Academy of Sciences of the Republic of Yakutia, found the intriguing mammoth bones.

Three lumbar vertebrae belonging to the “Pavlov mammoth”. Credit: I.S. Pavlov.

Immediately, the researchers noticed marks on the bones and began to wonder whether these were evidence of human hunting.

All of the bones from the almost complete skeleton bore marks on them, although that doesn’t necessarily mean they were made by human cutting tools. Scavengers biting the carcass, as well as natural processes such as the shifting of sediments and geological pressure may also explain the cut marks.

Speaking to Gizmodo, Olga Potapova, a paleontologist with The Mammoth Site in South Dakota and an associate researcher with the Academy of Sciences of Yakutia and the Russian Academy of Sciences, makes a case that these marks were anthropogenic. She says that the fossils have a large number of long and very thin cuts clustered in a parallel fashion. Cuts made by natural processes look more like random scratches.

Researchers also found embedded stone objects in the tusk, as well as a bone object lodged into the scapula (shoulder bone). These may have been the remnants of a weapon made from bone, Potapova says.

The mammoth scapula with a bone object embedded inside it. Credit:Innokentiy Pavlov.

The skull of the mammoth was broken in a similar fashion to the skulls of 32 mammoths from a site in the Russian Plain known as the “Yudinovo” site. Previously, researchers concluded that the mammoth skulls were fractured by human hunters who consumed the animals’ brains for food.

But in the absence of adjacent human artifacts or some other kind of direct evidence of human intervention, the contention that the Kotelny mammoth was butchered by human hands is still speculative.

To learn more, the researchers hope to return to the island soon, where they hope to uncover evidence of Paleolithic hunters at the site.

Strange dinosaur found in Brazil had stiff rods on its shoulders

Ubirajara jubatus was not your typical dinosaur. The newly described, chicken-sized creature had a mane of long fur down its back and a pair of stiff ribbons projecting back from each shoulder. These flamboyant features served to impress potential mates or intimidate adversaries, more than 110 million years before the first peacocks evolved.

The new species was discovered while researchers examined fossils in the collection of the State Museum of Natural History in Karlsruhe, Germany.

Immediately, the international team of researchers, including David Martill, a professor of palaeobiology at the University of Portsmouth, were stunned by the stiff ribbons projecting from the small dinosaur’s shoulders.

These ribbons weren’t bones, nor scales or fur. Instead, the long, flat ribbons were made of keratin, the same material that hair and feathers are made of. Strikingly, the researchers could tell all of this judging from x-ray scans of previously hidden skeletal elements encased in two slabs of stone from Brazil’s Crato Formation, a shallow inland sea laid down about 110 million years ago.

“Interpreting crushed bones is always challenging and it is very easy to get things wrong,” Martill told ZME Science.

But why go to all this trouble if these ribbons didn’t serve to immediately put food on the table, especially if it made you a walking target to predators? While it’s true that survivability drives the evolution of species through natural selection, evolution also favors reproduction, so individuals who were selected for their sexual fitness were naturally favored and could pass on their genes.

The peacock is famous in this regard and is often used as a prime example of sexual selection. With his long, colorful feathers trailing behind him, the male peacock signals to the world: ‘Behold! I spare no resources to adorn myself even if that means making many foes.’ For some reason, females find that very appealing.

We may imagine that Ubirajara jubatus used in many regards its long shoulder ribbons as a peacock’s tail.

“I suppose that if the adornments were on the tail it could be called a peacock, but these are on the shoulders, so maybe it should be the ‘Captain’,” Martill said jokingly.

Although it’s impossible to determine the sex of an individual with 100% accuracy, its size suggests that it was a young male. Perhaps the small dinosaur was still learning how to use its dazzling ribbons to woo potential mates when it died.

These ribbons were positioned in such a way as not to impede freedom of movement in the arms and legs. Its long, thick mane is believed to have been controlled by muscles, so it could have raised similar to the way a dog raises its hackles or a porcupine raises its spines when threatened. But when it didn’t require any display, the mane could be lowered close to the skin, allowing the dinosaur to move swiftly through dense vegetation.

Bizarre as it might have been, Ubirajara jubatus is an important contribution to the fossil record of feathered non-avian dinosaurs, which are very scarce in Latin America.

“Everybody loves dinosaurs and usually are thrilled when we can say something new or fascinating about them. And this little dinosaur has lots of new things about it. What’s next? Well, I have to wait to see what comes out of the ground on my next field trip,” Martill said.

The findings appeared in the journal Cretaceous Research.

Scientists trace origins of flight with pterosaur lost precursor

A high flying Pteranodon, a genus of pterosaur. Creidt: Elenarts / Adobe Stock.

Pterosaurs were the very first vertebrates to evolve powered flight nearly 230 million years ago. Previously, only insects were capable of flying. However, the origin of pterosaurs has always been wrapped in mystery since no major relative had been identified — until now.

In a new study published today in the journal Nature, paleontologists at Virginia Tech have described a group of “dinosaur precursors”, known as lagerpetids. According to the researchers, these are the closest relatives of pterosaurs, filling a gap in their evolutionary history that had been eluding scientists for the past 200 years.

‘Where do pterosaurs come from and how did they gain flight?’ is one of those ‘big’ questions that we know little about largely because pterosaurs appear in the fossil record in nearly their full form. We have known for decades that pterosaurs are dinosaur cousins, but there was little to fill in the gap between the two until recently – enter lagerptids,” Sterling Nesbitt, professor of geobiology at Department of Geosciences in the College of Science at Virginia Tech and co-author of the new study, told ZME Science.

Artistic rendering of Dromomeron (foreground) and associated dinosaurs and relatives. Credit: Donna Braginetz.

The study is the culmination of 15 years of work by five research groups across six different countries and three continents — and it all came together thanks to the braincase of a lagerpetid, known as Dromomeron gregorii, which had been gathering dust in a drawer in the fossils collections of the University of Texas at Austin.

“The fossil was found in the late 1930s or early 1940s, and was sitting in the collection untouched until I recognized its potential for understanding lagerpetid skull structures. It was thrilling to find the partial skull,” Nesbitt said.

“Anytime we find out something new about a fossil is incredibly exciting. It’s even better when it’s something that was there all along. The Dromomeron fossils were collected by people in the Works Progress Administration nearly 80 years ago, so they weren’t scientists that were doing that work. They did an amazing job carefully collecting these tiny fossils, and they ended up being key for our study. Museum collections are vital for preserving specimens until all the right pieces come together to interpret them in a new way,” Michelle Stocker, assistant professor of geobiology at Virginia Tech and co-author of the study, told ZME Science.

Further investigation of the braincase showed that these reptiles had a fairly good sense of balance and were likely agile animals. Other numerous lagerpetid partial skeletons from the United States, Brazil, Argentina, and Madagascar filled in critical gaps in the fossil records.

These fossils gave paleontologists confidence in their assessments of lagerpetids: small, wingless reptiles that lived across the supercontinent of Pangea during the Triassic, from 237 to 210 million years ago.

A partial skeleton of Lagerpeton (hips, leg, and vertebrae) from ~235 million years from Argentina. Credit: Virgina Tech.

“The fossils of lagerpetids and early pterosaurs are spread across the world (when they lived, the world was connected into Pangea) so it took time to see many of the fossils. One of the best aspects of this project was working with such an amazing group of scientists around the world – we came together to solve a long-standing problem,” Nesbitt said.

In order to reconstruct the brains and sensory systems of the lagerpetids, the researchers used micro-computed tomographic (μCT) scanning on the skulls included in the study. This technology enabled the team to generate 3-D models of the brain and inner ear anatomy of these tiny, fragile fossils without having to make any cuts.

“We were able to make a lot of our interpretations because of the application of CT technology to look at the inner portions of these fossils in a non-destructive manner. Features of the brain and inner ear wouldn’t have been possible to see without either this technology or destroying the specimen to get the data, so this has been a groundbreaking way to ‘see inside’ delicate fossils,” Stocker said.

Strikingly, the researchers found that the lagerpetids had already evolved some of the neuroanatomical features that allowed the pterosaurs to fly. According to Nesbitt, pterosaurs and lagerpetids share numerous characteristics across their skeletons, especially in the jaws, teeth, and braincase.

Paleontologists used to think that pterosaurs are an example of accelerated evolution judging from their unique body plan. But the lagerpetids fossils show that pterosaurs weren’t special — we were just missing some important puzzle pieces.

Two giant Arambourgiania pterosaurs sharing a small theropod for dinner. Credit: Mark Witton.

Some questions still remain, though. Chief among them is where are the lagerpetids wings? Perhaps they were only one or two steps away — only the discovery of new transitional fossils may help shed more light.

“Pterosaurs are fascinating because they are the first group of vertebrates to achieve flight. How and when they did that has always been a mystery, and it’s something that required both existing fossils in museum collections and fieldwork to find new fossils in order to finally decipher that story,” Stocker said.

“Our research group is focused on the animals and ecosystems in the Triassic Period, and we’re so excited to get back out in the field and travel to museums as soon as is safe. Understanding the early evolution of pterosaurs is just one of the many exciting projects our students are pursuing in the Triassic. It’s important for both our students and the public to understand how important paleontology is for understanding and appreciating life on our planet, and also to understand how vital museums and museum collections are for facilitating that understanding. We should all take care of these representations of our shared evolutionary history,” she added.

“We will keep unlocking the mysteries of the origin of dinosaurs, pterosaurs, and crocodile-like animals, particularly in the Triassic Period,” Nesbitt said.

Newly-discovered fossil lizard shows how uncertainty can lead to better science

A skull unearthed in 1971 and stored at Yale’s Peabody Museum of Natural History has finally been studied and described — uncovering a new species.

Lizard skull fossil is new and 'perplexing' extinct species
Left lateral view of the Kopidosaurus perplexus skull. Image credits Simon Scarpetta.

Lizard fossils aren’t particularly plentiful, as their bones tend to break apart rather easily. Most of the fossils we do have of them, therefore, come as isolated fragments, not complete specimens. That’s what makes the discovery of the present fossil, a beautifully-preserved skull about one inch long with a mouth full of sharp teeth, all the more exciting. Based on the skull, University of Texas at Austin graduate student Simon Scarpetta described a new fossil species.

New lizard on the block

“Anytime you find a skull, especially when you’re trying to figure out how things are related to each other, it’s always an exciting find,” Scarpetta says.

Scarpetta found the skull back in 2007 and brought it back to the Jackson School of Geosciences at The University of Texas for study. It turned out to be a completely new species, which he christened Kopidosaurus perplexus. The first half of its name is a reference to the lizard’s teeth and their distinct curvature — a kopis was a type of curved sword used in ancient Greece. The second part is a nod to how “perplexing” it’s been to determine where the lizard fits on the tree of life, according to Scarpetta. It simply fits in several spots equally well.

K. perplexus could belong to one of two families of lizards, but we don’t have enough information to tell which is the right one. Adding to the uncertainty is that the relationship between these groups is different between the different evolutionary trees we currently have at our disposal. Scarpetta looked at three of them, each constructed by different researchers studying reptile lineages based on DNA data, and found several places into which the ancient lizard could fit snugly.

As such, the species raises an important point for paleontology: just because a species fits on one branch of the tree of life doesn’t mean that it’s supposed to be there, or that it doesn’t fit on another one.

“The hypothesis that you have about how different lizards are related to each other is going to influence what you think this one is,” Scarpetta said.

For fossils, where DNA information isn’t available, paleontologists rely on the animal’s morphology (anatomical structure) to determine how it relates to other long-dead species. In essence, because animals evolve from one another, related species will share structural elements — like how cars of a particular brand share particular design elements, for example. The more such similarities between two specimens, the more likely it is that they’re related.

Lizard skull fossil is new and 'perplexing' extinct species
A computer tomography image of the skull in left lateral view. Image credits Simon Scarpetta.

Scarpetta created a digital scan of the skull in order to better study it. He found certain details that helped him determine this was a new species altogether, but some elements overlapped with features from several other lizard lineages. All of those lineages, he explains, belong to the Iguana group, which includes today’s chameleons, anoles, and iguanas. He later compared the skull to several Iguana evolutionary trees — on each, the animal fit equally well in two general spots, he explains.

It’s far from the only species that could easily fit into multiple places on the tree of life, he adds. But the study goes a long way towards showcasing how complicated this process can be, and why accepting a degree of uncertainty in our findings can help lead to better, more accurate science in the long run.

The paper “Effects of phylogenetic uncertainty on fossil identification illustrated by a new and enigmatic Eocene iguanian” has been published in the journal Scientific Reports.

Gourmet pterosaurs constantly improved their flight — until they were wiped out by killer asteroid

Two giant Arambourgiania pterosaurs sharing a small theropod for dinner. Credit: Mark Witton.

Pterosaurs were the very first vertebrates to evolve powered flight nearly 230 million years ago. Previously, only insects were capable of flying. But these first fliers were a bit clumsy, and it took a while before pterosaurs could reach their full potential. According to a new study published today in the journal Nature Communications, the ancient flying reptiles became better fliers at a constant rate until they went extinct 65 million years ago.

“Meaning that on average for 150 million years descendants were better flyers than their ancestors. This is a quite striking and unique demonstration of Darwin’s idea of descent with modification as species get better in their environment. I was certainly surprised to see such a clear demonstration of that!” Chris Venditti, Lecturer in Evolutionary Biology at the University of Reading in the UK and lead author of the new study, told ZME Science.

Bigger, better fliers

Pterosaurs were airborne animals that were closely related to dinosaurs. Like other flying animals, these reptiles generated lift with their wings, performing the same kinds of motions as birds and bats. They became quite good at it, traveling over long distances where they occupied new habitats across the world. Eventually, they branched out into an enormous array of species, including the largest winged-animals ever.

But this journey wasn’t straightforward. By studying the fossil records by employing new statistical methods, Venditti and colleagues reconstructed the evolution of the pterosaur flight dynamics across millions of years. Their findings suggest that natural selection acted to increase flight efficiency in these animals constantly since the time they first appeared in the fossil record until their premature extinction when an asteroid impact wiped them out, along with all non-avian dinosaurs.

There was only one exception to this pattern.

“A group of pterosaurs called azhdarchoids buck this trend. There are many hints in the scientific literature that suggests that this group had more terrestrial affinities than other pterosaurs. Some had inflexible necks which are not ideal for efficient flying, others left fossil tracks indicating terrestrial proficiency, and yet others had adaptations associated with ground-dwelling generalist foraging or wading foragers that fed on hard-shelled organisms at water margins. So, it seemed that these azhdarchoid pterosaurs did not rely on flight so much and our results support that – whilst they could fly, they might have only done so when they needed to. Some of these groups of pterosaurs were enormous (as tall as a giraffe),” Vendetti said.

An Arambourgiania pterosaur with a giraffe and average-sized human to scale. Credit: Mark Witton.

Besides increasingly better flight performance, the researchers also showed that pterosaurs grew in size over time but only after birds first appeared. According to Vendetti, this was expected given Cope’s Rule —  the tendency for organisms in evolving lineages to increase in size over time — and the interactions between the two groups of flying animals suggest that birds outcompeted pterosaurs at the small size range.

Interestingly, pterosaurs not only got bigger, their wings grew even larger.

“Through time pterosaurs got bigger wings than we would expect for their size – their relative wing size increased through time. So, they got bigger, but the wings got even bigger! All other things equal then, in turn, this leads to increased flight performance. In Azhdarchoids that buck the trend, even though they were some of the largest pterosaurs, relatively speaking they had small wings (for their size),” Vendetti said.

From beetles to fish: how pterosaur diet evolved

Another article published today in the same edition of Nature Communications also investigated pterosaur evolution, this time from a dietary perspective.

By studying the wear and tear of fossilized teeth from numerous pterosaur species, researchers at the University of Birmingham in the UK, led by Jordan Bestwick, could reconstruct what 17 different species of pterosaurs ate.

Dimorphodon, for example, ate a mix of vertebrates, Rhamphorhynchus ate fish, and Austriadactylus ate ‘hard’ invertebrates such as beetles and crustaceans, the authors concluded.

“I found large dietary diversity between pterosaurs as a group, ranging from carnivores, piscivores (fish eaters) to consumers of crunchy invertebrates and even generalists. In some instances this reaffirmed our current understanding of the diets of some species, whereas in others they provided completely new insights into diet,” Bestwick told ZME Science.

The researchers were able to infer what pterosaurs ate millions of years ago by studying the marks left on their teeth. Different kinds of foods leave different impressions, which reflect a creature’s diet.

Bestwick and colleagues used a technique called microwear texture analysis, which they previously employed on modern reptiles such as crocodiles and monitor lizards. Since the technique was able to determine foods found in known modern reptile diets, the researchers were confident to try it out on extinct reptiles such as pterosaurs.

“We found that the earliest pterosaurs consumed mostly invertebrates and that the later species were the more obligate carnivores and piscivores. What was really interesting is that this dietary shift sped up around the 150 million year mark which is around the same time that birds were evolving. Further study is needed to know whether our finding is just a coincidence or actually represents a trend where the evolution of birds changed the trajectory of pterosaur evolution, but does provide a new voice into the fiercely debated topic on pterosaur and bird competition,” Bestwick said.

“We also found evidence of one pterosaur shifting its diet as it grew up. Rhamphorhynchus lived in Germany around 150 million years ago and its complete life-history is preserved in the fossil record, from hatchlings no bigger than a sparrow, to adults about the size of a gannet. As Rhamphorhynchus grew up it shifted its diet from invertebrates to fish. This dietary shift is observed in many crocodilians and gives a clue into how pterosaurs looked after their young. Most reptiles do not feed their young and so young individuals eat different foods to the adults. Birds, on the other hand, feed their helpless young and so the young are consuming the same foods as the adults. That Rhamphorhynchus changed its diet provides a clue that maybe pterosaurs grew up like reptiles, despite flying like birds,” he added.

The two studies completement each other nicely, enriching our understanding of nature’s pioneering fliers.

“I think our study is a striking demonstration of how natural selection sculpts biological organisms through time by natural selection to be better in their environment. It also provides a blueprint to objectively study evolution through millions of years,” Venditti said.

“Pterosaurs are one of the most famous groups of prehistoric animals in the public eye (although they are colloquially referred to as ‘pterodactyls’) and are like nothing that is alive today. Microwear analysis is truly a window into the past that enhances and even changes our understanding of how these animals lived, grew up and evolved, makes them more like real animals, rather than as monsters you see in films,” Bestwick added. 

Tiny 200-million-year-old teeth show the first mammals were actually more like reptiles

Cementum (the structure that locks tooth roots to the gum) from the earliest mammals showed they lived much longer than previously thought. Credit: Nuria Melisa Morales Garcia.

We mammals might be high and mighty now, but it wasn’t always like this. Some 200 million years ago, the earliest mammals were tiny shrew-like creatures that lived in the shadows of the dinosaurs. In fact, the dominance of the dinosaur lineage ensured that our distant mammalian ancestors never grew larger than a cat during the next 145 million years of evolution.

There is still much we don’t know about the very first mammals, and how these little creatures morphed into a panorama of mammals with fur, hooves, fangs, as well as streamlined swimmers in the deep ocean. But a new study might cast more light onto the dawn of the age of mammals.

Mammalian evolution was more complicated than previously thought

In this new research, scientists at the University of Bristol in the UK and the University of Helsinki in Finland analyzed ancient teeth belonging to Morganucodon and Kuehneotherium, two of the earliest mammals known so far, using powerful X-rays.

Like counting a tree’s rings in order to determine its age, the researchers analyzed growth rings deposited every year in the cementum of the teeth, the structure that locks tooth roots to the gum. This procedure allowed the scientists to determine how long these animals lived.

Similarly sized modern-day mammals, such as mice and shrews, tend to survive only 1-2 years in the wild. But the researchers were surprised to find the ancient mammals lived much longer.

“The surprisingly long lifespan of these mammals, 14 years for Morganucodon and 9 for Kuehneotherium, are much longer than living small-bodied mammals, and more similar to small reptiles. This suggests a comparably slower pace of life to warm-blooded mammals and that the earliest mammals had yet to develop this important feature,” Dr. Elis Newham, Research Associate at the University of Bristol and lead author of the new study, told ZME Science.

Reconstruction of Morganucodon (left) and Kuehneotherium (right) hunting in Early Jurassic Wales 200 million years ago. Credit: John Sibbick, Pam Gill.

The project is the brainchild of Newham’s supervisor, Dr. Pam Gill, who is a senior research associate at the University of Bristol. Gill was inspired to employ advanced imaging technology on ancient mammalian fossils after one of his colleagues had a tooth removed that they wanted to get X-rayed because ” it can tell all sorts of things about your life history.” Why not do the same to learn more about the lives of the first mammals?

Over a period of six years, during which Newham took this project up for his MSc in Palaeobiology at the University of Bristol, and then as a Ph.D. at the University of Southampton, hundreds of teeth were examined. The fossils were scanned at the European Synchrotron Radiation Facility and the Swiss Light Source, among the world’s brightest X-ray light sources, in France and Switzerland, respectively.

“Perhaps the greatest challenge during the study was the very intense experiments at the synchrotrons. Located in Switzerland and France, the synchrotrons we visited operate 24-hours a day and so often require gruelling shifts through the night where small crews of scientists are continually swapping specimens, firing X-rays and drinking coffee!” Newham told me.

Synchrotron micro-CT scan of a fossil Morganucodon tooth root from 200 million years ago. Each annual growth ring is less than a hundredth of a millimeter thick. Credit: Elis Newham.

The cementum scans allowed the researchers to reconstruct the tooth roots in 3D, showing that Morganucodon lived for up to 14 years, and Kuehneotherium for up to nine years.

What’s more, the researchers also measured the size of major blood vessels in the femur bone of Morganucodon. This showed that Morganucodon could have had higher blood flow than living reptiles, but it was still significantly lower than that of living mammals. “This in-turn indicates that the earliest mammals could not sustain the same level of demanding exercise of living mammals,” Newham said.

These intriguing results suggest that the earliest mammals weren’t really warm-blooded like today’s mammals, although even 200 million years ago they had relatively large brains and whiskers.

“We are continuing using the method developed in this paper to study the physiological evolution of mammals through their early stages, to plot the pace and pattern of the evolution of warm-bloodedness. We are also looking at the possibility of analyzing other important life history information from the cementum growth rings in both living and fossil mammals,” Newham concluded.

The findings appeared in the journal Nature Communications.

Pristinely preserved prehistoric ‘hell ant’ had unique headgear

Hell ant Ceratomyrmex ellenbergeri grasping a nymph of Caputoraptor elegans (Alienoptera) preserved in amber. Credit: NJIT, Chinese Academy of Sciences and University of Rennes, France

A piece of amber has frozen in time a spectacular scene from 99 million years ago. The remarkable fossil clearly shows one of the earliest known ants grasping the neck of its prey, an extinct cockroach relative. The ‘hell ant’, as researchers refer to it, attacked the insect with its two sharp mandibles and a strange, horn-like protrusion on its head.

Fossils encased in rock are often two-dimensional and you have to be an extremely skilled paleontologist in order to identify the fossilized ancient species and its defining features. Amber is totally different, though. This natural time capsule can preserve creatures in 3D for up to hundreds of millions of years (basically for as long as there’s been tree resin). Intricate detail and even soft tissue like cartilage, feathers, or pollen can sometimes be trapped inside amber.

Such an amber fossil retrieved from Myanmar offers an unprecedented glimpse into the lives of one of the first ants known to science.

The newly identified prehistoric ant, known as Ceratomyrmex ellenbergeri, used its scythe-like mandibles in a vertical motion to trap its prey. Its unusual horn-like appendages likely served to wedge cockroaches and other insects against the snapping mandibles. This is the first direct evidence of such a predatory strategy.

By contrast, modern ants grasp their prey by moving their mouthparts laterally. They also obviously lack the hell ant’s bulky headset.

“Fossilized behavior is exceedingly rare, predation especially so. As paleontologists, we speculate about the function of ancient adaptations using available evidence, but to see an extinct predator caught in the act of capturing its prey is invaluable,” said Phillip Barden, assistant professor at New Jersey Institute of Technology’s Department of Biological Sciences and lead author of the study. “This fossilized predation confirms our hypothesis for how hell ant mouthparts worked … The only way for prey to be captured in such an arrangement is for the ant mouthparts to move up and downward in a direction unlike that of all living ants and nearly all insects.”

Hell ants suddenly vanished, just like other early ant lineages, during the Cretaceous-Paleogene mass extinction event 65 million years ago. The same event caused by a cataclysmic asteroid impact also wiped out all non-avian dinosaurs.

“Since the first hell ant was unearthed about a hundred years ago, it’s been a mystery as to why these extinct animals are so distinct from the ants we have today,” Barden added. “This fossil reveals the mechanism behind what we might call an ‘evolutionary experiment,’ and although we see numerous such experiments in the fossil record, we often don’t have a clear picture of the evolutionary pathway that led to them.”

Horn-like appendages were surprisingly common among the 16 species of hell ants identified thus far. Some species similar to Ceratomyrmex used their elongated horns to grasp prey externally, while others such as Linguamyrmex vladi (named after Vlad the Impaler) used metal-reinforced horn on its head to impale prey.

Phylogeny and Cephalic Homology of Hell Ants and Modern Lineages. Credit: NJIT, Chinese Academy of Sciences and University of Rennes, France.

Based on the morphological analysis performed by Barden and colleagues, the earliest hell ant ancestors must have first moved their mouthparts vertically. This arrangement allowed the mouthparts and head to function together in a way that was totally unique to this now-extinct lineage.

“Integration is a powerful shaping force in evolutionary biology … when anatomical parts function together for the first time, this opens up new evolutionary trajectories as the two features evolve in concert,” explained Barden. “The consequences of this innovation in mouthpart movement with the hell ants are remarkable. While no modern ants have horns of any kind, some species of hell ant possess horns coated with serrated teeth, and others like Vlad are suspected to have reinforced its horn with metal to prevent its own bite from impaling itself.”

Questions this remain as to why this amazing lineage of ant predators went extinct after being successful for 20 million years, whereas the ancestors of modern ants went on to survive and flourish to this day. To cast more light on the extinction of hell ants, Barden and colleagues plan on seeking other species from newly found fossil deposits.

“Over 99% of all species that have ever lived have gone extinct,” said Barden. “As our planet undergoes its sixth mass extinction event, it’s important that we work to understand extinct diversity and what might allow certain lineages to persist while others drop out. I think fossil insects are a reminder that even something as ubiquitous and familiar as ants have undergone extinction.”

The findings appeared in the journal Current Biology.

Prevalent bone disease already existed during the Permian, fossil study finds

Paget’s bone disease is the second most common bone disorder, after osteoporosis. Now, a new study finds that it has been around since the early days of the Permian, some 289 million years ago.

Susceptibility to this type of disease may extend back to the Early Permian. Image credits: Yara Haridy/Museum für Naturekunde, Berlin.

Almost 300 million years ago, a lizard-like animal was walking through what is now a cave in Richards Spur, Oklahoma. The animal belonged to an extinct group of creatures called varanopids — relatives of the earliest ancestors of mammals and reptiles.

Paleontologists led by Yara Haridy of the Museum für Naturkunde in Berlin found an isolated pair of tail vertebrae belonging to the animal. They examined it using micro-CT scanning, analyzing both the internal and external structure of the elements. In some areas, they found that the bone had been thinned, while in others, there was excessive bone growth, culminating in the fusion of the two vertebrae.

This is very similar to Paget’s disease, researchers say. In this condition, the body’s bone recycling process starts to malfunction. The main symptom of the disease is an excessive bone breakdown and subsequent disorganized new bone formation. This causes a weakening of the bones, which is manifested through pain and increased injury risk. The cause of the disease, however, remains unknown.

Paget’s disease has been diagnosed in humans as well as other animals, both mammals and reptiles. It’s even been diagnosed in an early Jurassic fossil. However, this is the oldest evidence ever found of the disease.

After conducting the scans, researchers conducted a differential diagnosis on the results. They mostly ruled out other conditions which could have caused the observed defects, and pretty much confirmed a condition similar to Paget’s. However, given the lack of a more complete skeleton, it’s hard to say just how widespread the disease was.

It’s also hard to say how the condition affected the animal. In humans, it’s often asymptomatic and doesn’t cause significant pain. If the disease wasn’t widespread for the varanopids, it probably wouldn’t have affected it in any significant way. However, if it was, then it would have conceivably caused some stiffness and pain.

Haridy comments:

“This enigmatic disease is still not well understood in humans, however finding something similar in an ancient animal likely links it to something deep in our bone biology. This study is a great example of how when palaeontologists have well preserved fossils we can tell a lot more than just what animals were present, we can explore their biology, physiology and even what diseases ailed them!”

Journal Reference: Haridy Y, Witzmann F, Asbach P, Reisz RR (2019) Permian metabolic bone disease revealed by microCT: Paget’s disease-like pathology in vertebrae of an early amniote. PLoS ONE 14(8): e0219662. https://doi.org/10.1371/journal.pone.0219662

Giant African Titanosaur had a heart-shaped tail

 

 

Titanosaurs belonged to a group of dinosaurs called sauropods — the largest terrestrial creatures that ever roamed the Earth. But while most sauropods disappeared during the Late Cretaceous 100 million years ago, Titanosaurs thrived during that period. However, the early evolution of this group is not that well known because not many fossils have been discovered.

An illustration of two titanosaurs in their natural environment. Image credits: Mark Wutton.

This is where Mnyamawamtuka moyowamkia comes in. Its name is derived from Swahili for “animal of the Mtuka (with) a heart-shaped tail”, in reference to the name of the riverbed (Mtuka) in which it was discovered and due to the unique heart-shape of its tail bones. Mnyamawamtuka was first discovered in 2004 when parts of its skeleton were found high in a cliff wall overlooking the seasonally dry Mtuka riverbed in Tanzania. Excavations continued, at times requiring extreme dedication: often, the digging team was suspended by ropes or climbing gear over the wall. If the digging would have been delayed even by just a few years, erosion might have destroyed much of this skeleton.

Digging the skeleton required a lot of dedication. Image credits: Gorscak & O’Connor.

Researchers note that the finding is particularly important as it provides a much-needed puzzle piece in understanding Titanosaur evolution, as well as the general evolution of African fauna during the Cretaceous.

“Although titanosaurs became one of the most successful dinosaur groups before the infamous mass extinction capping the Age of Dinosaurs, their early evolutionary history remains obscure, and Mnyamawamtuka helps tell those beginnings, especially for their African-side of the story,” said lead author Dr. Eric Gorscak. “The wealth of information from the skeleton indicates it was distantly related to other known African titanosaurs, except for some interesting similarities with another dinosaur, Malawisaurus, from just across the Tanzania-Malawi border,” noted Dr. Gorscak.

An illustration depicting Mnyamawamtuka and the parts of its skeleton which have been uncovered. Image credits: Gorscak & O’Connor.

This isn’t the only important finding from the area. Among others, researchers have found evidence of two other titanosaurs (Shingopana songwensis and Rukwatitan bisepultus), a mammal-like crocodile (Pakasuchus kapilimai), evidence of the monkey-ape split, as well as early evidence of insect farming.

This new find also suggests a close relationship titanosaurs from Africa and South America — two continents which were joined together 180 million years ago.

“This new dinosaur gives us important information about African fauna during a time of evolutionary change,” said Judy Skog, a program director in the National Science Foundation’s Division of Earth Sciences, which funded the research. “The discovery offers insights into paleogeography during the Cretaceous. It’s also timely information about an animal with heart-shaped tail bones during this week of Valentine’s Day.”

Journal Reference: Gorscak E, O’Connor PM (2019) A new African Titanosaurian Sauropod Dinosaur from the middle Cretaceous Galula Formation (Mtuka Member), Rukwa Rift Basin, Southwestern Tanzania. PLoS ONE 14(2): e0211412. https://doi.org/10.1371/journal.pone.0211412

Enigmatic creatures that lived 630 million years ago were animals — but not like anything we’ve seen before

The year is 600 million BC — and the Earth is a completely different place from what we know it to be. The most advanced creatures on Earth are (probably) the so-called Ediacaran fauna. To the untrained eye, they look just like plants, static and seemingly inactive. But things are not always as they seem.

The Ediacaran fauna has fascinated scientists for years, trying to figure out whether they were algae, fungi, animals, or of a completely different kingdom. Now, a group of scientists believes they finally have the answer. In a new study, they present convincing arguments that the Ediacaran fauna were indeed animals.

Dickinsonia costata, an iconic Ediacaran organism. Image credits: Verisimilus / Wikipedia.

They dominated the seas all around the world, with traces of their fossils appearing in all corners of the Earth. The Ediacaran fauna first emerged some 635 million years ago, only to disappear quickly after the Cambrian Explosion, some 542 million years ago. Part of the reason why these creatures have been so hard to pin down is their unique anatomy. They featured tubular-type fronds, which branch out in a fractal matter. They bear a resemblance to mollusks (and other creatures with a similar symmetry), but they also resemble some sponges and even jellyfish. Some paleontologists have suggested that they represent a completely extinct branch of life, perhaps even a link between plants and animals.

But a new study says that they were definitely animals — and it brings the evidence to back it up.

Jennifer Hoyal Cuthill at the Tokyo Institute of Technology and the University of Cambridge in the United Kingdom and Jian Han at Northwest University in Xi’an, China, analyzed more than 200 fossils of a 518-million-year-old marine species named Stromatoveris psygmoglena.

It was already believed that this creature was some sort of animal, but it was not clear whether it also belonged to the Ediacaran fauna. If this connection could be established, then it would indicate that the Ediacaran fauna were indeed animals.

Cuthill and Han ran a computer analysis, using anatomical features to reconstruct evolutionary relationships between Stromatoveris and creatures genetically close to it. They found that Stromatoveris, just like all other Ediacaran organisms they analyzed, didn’t belong to any living animal group (or phylum). They have their own branch, somewhere between the simple sea sponges and more complex animals such as worms and mollusks.

“This branch, the Petalonamae, could well be its own phylum, and it apparently lacks any living descendants,” Hoyal Cuthill says.

There’s a very good chance that the Ediacaran fauna were the world’s first animals, but this opens up another thorny question: the extinction of the Ediacaran was linked to Cambrian animals. But if they themselves were animals (and some survived well into the Cambrian), the explanation isn’t so elegant anymore.

“It’s not quite so neat anymore,” she says. “As to what led to their eventual extinction I think it’s very hard to say.”

The study was published in Paleontology.

Big dinosaur is a big piece of evidence for Africa’s geological past

Africa is a fantastic place to search for humanoid fossils but when it comes to dinosaurs, things are a bit different. That’s why this new find by paleontologists working in Egypt is thrilling: it fills up what was an empty page in the continent’s geological history.

Image credits: Andrew McAfee, Carnegie Museum of Natural History.

If you think the world has changed a lot in the past few decades, you should have seen it during the Cretaceous. Some 100 million years ago, the Earth was a completely different place, with lush vegetation and a flourishing population of reptiles. Flowering plants had just emerged, but reptiles ruled the planet — both on land, and on the sea. Huge beasts, the kind the Earth has never since seen roamed on all four corners of the globe. The biggest of them all were, rather unintuitively, gentle giants.

The typical appearance of these gentle giants included a long neck and tail, as well as four sturdy legs to support their body. Mansourasaurus shahinae, the newly found species, is no exception.

Mansourasaurus lived about 80 million years ago, and the fossils suggest that individuals measured around 8 to 10 meters (26 to 33 feet) — about as big as a bus. It had a long neck and rough, bony plates on its skin. Paleontologists were excited to make the discovery, likening it to a paleontological Holy Grail.

“It was thrilling for my students to uncover bone after bone, as each new element we recovered helped to reveal who this giant dinosaur was,” said Dr. Hesham Sallam of Mansoura University, who led the research.

Artistic depiction of how the dinosaur might have looked like. Image credits: Andrew McAfee, Carnegie Museum of Natural History.

Study co-researcher Dr. Matt Lamanna of Carnegie Museum of Natural History said that his jaw “hit the floor” when he saw photos of the fossils.

“This was the Holy Grail,” he said. “A well-preserved dinosaur from the end of the Age of Dinosaurs in Africa that we palaeontologists had been searching for for a long, long time.”

It’s not just that this is a new and interesting species, but it starts filling up what was a rather blank page in the African fossil record. Not much at all is known of the Cretaceous dinosaurs in today’s Africa.

The left dentary, or lower jaw bone, of the new titanosaurian dinosaur Mansourasaurus shahinae as it was found in rocks from the Upper Cretaceous (~80 million-year-old) Quseir Formation of the Dakhla Oasis, Egypt. Credit: Hesham Sallam, Mansoura University.

There’s a huge gap in the fossil record, just as the continents were undergoing severe tectonic changes, and the world was nearing one of the biggest extinctions in history. For most of the dinosaurs’ history (the Triassic and Jurassic periods), almost all of the planet’s landmass was concentrated in a single continent: Pangaea. During the Cretaceous, the continents started to split up and move towards the shape we see today. This is why scientists sometimes find the same (or very similar) species in completely different parts of the world: those different parts were once together.

Mansourasaurus shahinae is a key new dinosaur species, and a critical discovery for Egyptian and African palaeontology,” said researcher Eric Gorscak, a postdoctoral research scientist at The Field Museum. This enables researchers to not only understand how these creatures moved and spread about, but also gives a unique insight into their evolutionary history.

“Africa remains a giant question mark in terms of land-dwelling animals at the end of the Age of Dinosaurs. Mansourasaurus helps us address long standing questions about Africa’s fossil record and palaeobiology – what animals were living there, and to what other species were these animals most closely related?”

However, while this is a key finding which opens up intriguing possibilities, it’s not the last piece of the puzzle — it’s only the first one. Hopefully, there will be many more coming soon.

“What’s exciting is that our team is just getting started. Now that we have a group of well-trained vertebrate paleontologists here in Egypt, with easy access to important fossil sites, we expect the pace of discovery to accelerate in the years to come,” says Sallam.

Journal Reference: Hesham M. Sallam et al. New Egyptian sauropod reveals Late Cretaceous dinosaur dispersal between Europe and Africa. doi:10.1038/s41559-017-0455-5.

Scientists take a deep look inside mysterious 580-million-year-old creatures

High-end technology meets one of the planet’s most ancient life forms to solve a long-standing mystery.

A virtual reconstruction through a CT scan. Image credits: Alana Sharp.

Pioneers of life

More than 600 million years ago, something strange happened on Earth: life started blooming with unprecedented force. Before that, life was simple, mostly microscopic and single-celled — quite dull. But the Ediacara fauna changed all that.  Trace fossils of the Ediacara fauna have been found worldwide, so we have some degree of familiarity with them, which is remarkable for something that happened so long ago. They represent the earliest known complex multicellular organisms, and emerged with such a force that paleontologists believe they changed the environment so much that they caused the world’s first mass extinction.

The Ediacarans themselves were pleated soft-bodied life forms — some up to 2 meters tall — that thrived from 580 to 540 million years ago. Their glory days faded quickly, however, when other “true” animals emerged and probably ate them to extinction.

To this day, they remain some of the most intriguing and mysterious creatures in history. We don’t really know what they were. Were they an animal of sorts? Were they more like plants? Even such simple questions are hard to answer when dealing with the Ediacarans. To make things even more intriguing, they exhibited an extreme range of variability. Size ranged from millimeters to meters; complexity from “blob-like” to intricate; rigidity from sturdy and resistant to jelly-soft.

Wanting to better understand them, British researchers carried out CT scans of two unusually well-preserved fossils. They carried out an initial analysis in 2013, and now, took it a step forward. The species, called Rangea (Rangeomorph genus) exhibits six-fold radial symmetry. It was one of the first organisms to reproduce sexually.

“This is the first look inside such a unique specimen of a rangeomorph,” says Alana Sharp of University College London, who led the team conducting the scans. “What has been made visible are internal structures like a central core.”

The fossil, external scan and internal CT scan of a rare Rangea fossil that hasn’t been flattened. Image credits: Alana Sharp

The scans of the fossils exhibit some unexpected features: one of the fronds had a three-dimensional shape, as opposed to most other fossils, who were rather flattened. This flattening process was likely caused by fossilization, but this one somehow escaped it. If all of them were inflated during their lifetime, this would indicate that they would increase their surface area as much as possible, probably to help them absorb as many nutrients as possible. The CT scans also showed a channel running from its central trunk. The lower part of this channel is filled with a different type of sediment than the rest of the body, perhaps supporting it as some form of a primitive skeleton.

Such beautiful images are a rare sight. Even though these organisms were likely quite common, 500 million years is a long time for something to preserve. We’re still just inching closer to uncovering their secrets. If we’re to do that, more fossils are necessary, and researchers are not on a quest to find them. It’s no easy feat.

“These beautiful, three-dimensional Ediacaran fossils are comparatively rare,” says Jennifer Hoyal Cuthill at the University of Cambridge. “There’s still so much to discover about what these creatures were and how they lived, and detailed information on their anatomy is very valuable.”

But even this new study fails to answer the most basic of questions: what were the Ediacarans? They represent a part of the tree of life that’s so different from us that we find it hard to comprehend how they came to be, and how they interacted with their environment. But we do know one thing: they were the first significant macroscopic creatures to emerge, and they paved the way for other animals to evolve. They were true pioneers, pioneers of life.

early dinosaur relative

Oldest dinosaur relative looked nothing like scientists imagined

We know a lot about dinosaurs but not nearly as much as about their early relatives. For years, scientists have speculated what these creatures might have looked and behaved like, based on thin and incomplete fossil records. Most assumed these would have looked like miniature dinosaurs, no bigger than a chicken, and walked on two legs. Paleontologists from Virginia Tech have toppled this belief with the latest discovery of a 245-million-year-old dino cousin.

early dinosaur relative

Artist impression of Teleocrater rhadinus hunting a cynodont, a close relative of mammals. Credit: Gabriel Lio, Museo Argentino de Ciencias Naturales.

Seven to ten feet long, with a long neck and tail, and four crocodylian-like legs, the newly described species of Teleocrater rhadinus looked nothing like scientists imaged it.

Teleocrater fossils were first discovered in Tanzania in 1933 by famed paleontologist F. Rex Parrington and studied by Alan J. Charig, who used to be the curator of Fossil Reptiles, Amphibians, and Birds at the Natural History Museum of London. Because the unearthed specimens lacked crucial skeleton parts, specifically the ankle bones, Teleocrater’s place in the evolutionary family tree was uncertain. Was this creature more related to dinosaurs or crocodiles?

This very important question was settled recently after scientists discovered the missing ankle bone and other new fragments in Southern Tanzania. Unfortunately, Charig passed away before this recent development but he would have most certainly been excited by the findings.

“The discovery of such an important new species is a once-in-a-lifetime experience,” said Sterling Nesbitt, an assistant professor of geosciences in the College of Science.

Teleocrater rhadinus is so spectacular because it sheds light on the distribution and diversity of the ancestors of crocs, birds, and dinosaurs. Pre-dating dinosaurs by some 15 million years, Teleocrater rhadinus, which means  “slender complete basin” alluding to the lean build, fills a large gap in the fossil record after a large group of reptiles called archosaurs split into two lineages. One’s the bird branch, which includes dinosaurs and birds, and the other is the crocodile branch which today is represented by alligators and crocodiles. Remarkably, Teleocrater is the earliest archosaur we’ve ever encountered.

Teleocrater and other dino cousins were widespread during the Triassic and lived in what’s today Russia, India, and Brazil. Though they preceded dinosaurs by millions of years, they went extinct before dinosaurs first appeared in the fossil record.

Next, Nesbitt and colleagues are heading back to southern Tanzania this year to look for more remains and missing parts of the Teleocrater skeleton.

“It’s so exciting to solve puzzles like Teleocrater, where we can finally tease apart some of these tricky mixed assemblages of fossils and shed some light on broader anatomical and biogeographic trends in an iconic group of animals,” said Michelle Stocker, a co-author of the new study which appeared in the journal Nature.

Paleontologists find ‘incredibly rare’ 52 million year-old fossilized berry

Geoscientists working in South America have uncovered an ancient berry, a fossilized fruit belonging to a family which includes tomatoes, potatoes, and petunias.

The new fossil groundcherry Physalis infinemundi from Laguna del Hunco in Patagonia, Argentina, 52 million years old. This specimen displays the characteristic papery, lobed husk and details of the venation. Credit: Ignacio Escapa, Museo Paleontológico Egidio Feruglio

Animal fossils are much more common than plant fossils. The fossilization process itself favors the preservation of animals, which often have bones or shells, and deters the preservation of plants or fruits – this is what makes this discovery so special.

The fruit is part of the Solanaceeae (or Nightshade) family, an important and highly diversified group of flowering plants. It was found in a fossilized rainforest in Patagonia, and researchers believe it to be a Physalis closely related to tomatillos. Tomatillos (along with ground cherries and husk tomatoes) are highly unusual in that they have papery husks that grow around their fleshy, edible berries. The entire family has a very poor fossil record, greatly limiting what we know about the evolutionary history of these plants. In fact, these new findings may very well force us to rethink what we thought we knew about nightshades.

“These astonishing, extremely rare specimens of physalis fruits are the only two fossils known of the entire nightshade family that preserve enough information to be assigned to a genus within the family,” said Peter Wilf, professor of geosciences, Penn State, who led the study. “We exhaustively analyzed every detail of these fossils in comparison with all potential living relatives and there is no question that they represent the world’s first physalis fossils and the first fossil fruits of the nightshade family. Physalis sits near the tips of the nightshade family’s evolutionary tree, meaning that the nightshades as a whole, contrary to what was thought, are far older than 52 million years.”

Dried fruit specimens of a modern coastal groundcherry, Physalis angustifolia, from Florida, showing characteristic lobes and venation similar to the new fossils from Patagonia. Credit: Peter Wilf, Penn State.

This feeling was echoed by other paleontologists. The area in Patagonia where the discovery was made is highly intriguing because it was a part of Gondwana, the supercontinent which included landmasses of South America, Antarctica, and Australia, during a warm period of Earth history, just before their final separation.

“Paleobotanical discoveries in Patagonia are probably destined to revolutionize some traditional views on the origin and evolution of the plant kingdom,” said N Ruben Cuneo of CONICET, Museo Palentologico Egidio Ferulgio.

Part of the reason why we’ve found so few nightshade fossils is that they’re extremely fragile and herbaceous. The leaves and flowers are basically completely unknown.

“These fossils are one of a kind, since the delicate papery covers of lantern fruits are rarely preserved as fossils,” Carvalho said. “Our fossils show that the evolutionary history of this plant family is much older than previously considered, particularly in South America, and they unveil important implications for understanding the diversification of the family.”

Dating was also challenging. Molecular dating of family trees relies on actual dates of fossils in the family to work from. But because previously dated fossils had very little diagnostic value, paleontologists instead dated the rocks in which the fossil was found. The fossils, 52 million years old, exhibit the same lobed husk and details of the venation as modern tomatillos.

Journal Reference: Peter Wilf, Mónica R. Carvalho, María A. Gandolfo, N. Rubén Cúneo. “Eocene lantern fruits from Gondwanan Patagonia and the early origins of Solanaceae,” Science, science.sciencemag.org/cgi/doi/10.1126/science.aag2737

The Types of Fossils and Other Rock-solid Fossil Facts

There are several ways of classifying fossils, depending on the process by which they form, the mineral and the underlying processes, but in the largest sense, fossils can be:

  • Body fossils
  • Trace fossils

Ah, fossils

Not as dramatic as an earthquake or as awe-inspiring as a volcano, but instrumental in shaping our understanding of the Earth. They are our only link to millions and millions of years of life that came before us. Almost everything we know about dinosaurs, ancient plants and countless other species of organisms we’ve learned from fossils. Geologists can use fossils to determine the age of rocks, to understand climate and environmental types from millions of years ago, and get an understanding of plate tectonics.

Fossils, scaring naughty children since millions of years before there were naughty children. Image credits albertr / Pixabay.

Fossils, scaring naughty children since millions of years before there were any naughty children.
Image credits albertr / Pixabay.

In other words, they’re incredibly useful even though they’re technically just a bunch of rocks. So how do they form? What kinds of fossils are there? Can you lick them?

The answer to that last question is yes. You should probably wash them first but still yes. The other two questions need more elaborate answers, so put on your hardhats and get those notebooks out because it’s paleontology time.

First thing first, how do they form?

A fossil represents the preserved remains or impressions of either whole or parts of ancient organisms. For the most part, they’re found in sedimentary rocks, although under certain conditions they could be preserved in metamorphic or igneous rocks — volcanic tufts, for example, a rock formed by volcanic ash.

Now, not every critter gets to become a fossil — else the world would be choke full of them, which it evidently is not. Certain conditions have to be met for organic matter to become fossilized, and the most important one is for the remains to be buried before they decompose. The faster this happens, the more features of the animal will be preserved. For example, if an animal dies in the sea and its body is slowly covered with sediment, we’ll probably find its fossilized bones. For an animal that got caught in quicksand, however, we may even see things such as impressions of skin and soft tissue.

The fish’s soft tissue can be clearly seen in this fossil, unlike the dinosaur from earlier.
Image credits The High Fin Sperm Whale / Wikimedia.

So to get a fossil you need the remains of an organism and some sediment to cover it before it fully decomposes. Most fossils we find today are formed in either marine environments or land areas with lots of water (such as swamps,) because they have high rates of sediment deposition and mobility. Year after year, new layers of material deposits over the animal’s remains — and in millions, even tens of millions of years, they get buried pretty deep. During this time, the sedimentary layer follows its natural cycle of lithification and, compressed by the weight of sediment above it, starts turning to stone, encasing the remains. By this point, some fossils rot away leaving behind a mold-like cavity which is them filled with new sediment in the shape of the former animal.

If the fossil doesn’t rot away, the huge pressure involved in lithification squashes the particles of sediment into each other, generating heat that cooks the remains enriching them in carbon — that’s why plant fossils usually take on brown or blackish hues. More resilient tissue such as shells, bone or wood can stand this pressure and remain inside the rock. Here one of two things happens — interstitial solutions either fill their pores with rock-forming minerals or dissolve them completely and fill the space with minerals that crystallize — that’s why I said fossils are technically just rocks.

The fossil and the rock that houses it can remain buried or, through various geological processes — mountain formation, for example — get pushed back up to the surface where the rock gets eroded, leaving behind the cast, ready to be found by enthusiastic paleontologists.

What can they expect to find?

All fossils are created through those three processes. They can be mold and cast, carbonized, or form through permineralization/replacement. So it might seem a bit weird that paleontologists categorize them in two “flavors,” but it actually makes sense.

The first type, known as body fossils, are the remains of an animal or plant — like bones, shells, and leaves. These can be mold and cast fossils, like the big dinosaur skeletons you can see in a museum, replacement fossils like petrified wood or whole body fossils — from insects caught in amber to mammoths encased in ice.

Fossil Coleoptera, Elateridae (Click beetles) in Baltic amber.
Image credits Manukyan Andranik / Wikimedia

The second type, known as trace fossils (or ichnofossils,) are records of organism’s lives but not parts of their body — these include footprints, track-ways, and coprolites.

Possitive ichinofosiil (worm tracks) in the Bright Angel Formation, Grand Canyon, USA. Image credits Grand Canyon National Park / Flickr

Positive ichnofossil (worm tracks) in the Bright Angel Formation, Grand Canyon, USA.
Image credits Grand Canyon National Park
/ Flickr

In geology, body fossils are used to determine the age of rocks — because we know the time-frames during which different animals or plants lived, we can estimate the age of the rocks based on what organisms we find. Trace fossils are very useful to determine the foot and the roof of a layer, in other words, which part was up and which was down as it sedimented. Imagine a worm wiggling over the sea floor, leaving a tiny dent behind it as it does. When the sand turns into sandstone, that little ditch will become a negative ichnofossil on the rock’s roof and a positive ichnofossil on the next layer’s foot.

I must gather these fossils for myself! Where can I find them?

First, you have to understand that each and every fossil is a miracle of chance – or rather, a statistical outlier. So many things have to go just right, over millions of years (the right animal has to die in the right spot, followed by the right climate and sedimentary influx to the area, burial, exondation, and erosion at the right moment) for you to find one that the mind just boggles. The first time I found a fossil I was literally jumping up and down with joy even though it was only one fish vertebra as tiny as the frontal camera on an iPhone.

That being said, if there’s one thing that life hasn’t lacked for it is numbers — the sheer quantity of animals and plants that have ever lived on Earth means that there’s a decent quantity of fossils to be found and more are created all the time. As a general rule, search for fossils in areas of erosion. Mary Anning, probably the most important fossil finder that you’re never heard of, did much of her fossil hunting in the sheer cliffs beside the English Channel.

For more detailed fossiliferous sites in the US, Fossilguy.com has a pretty extensive guide set up that’s definitely worth your attention.

Bone-crushing dog roamed eastern North America 12 million years ago

Paleontologists have identified an ancient hyena-like canine that occupied eastern North America approximately 12 million years ago. The coyote-sized dog had a massive jaw which scientists say it used to crush bones.

Illustration of Cynarctus by Mauricio Antón from “Dogs, Their Fossil Relatives and Evolutionary History.” Photo: University of Pennsylvania

Illustration of Cynarctus by Mauricio Antón from “Dogs, Their Fossil Relatives and Evolutionary History.” Photo: University of Pennsylvania

The first fossils of  Cynarctus wangi, as the new species was named, were found by a an amateur collector in Maryland, under the Choptank Formation in Maryland’s Calvert Cliffs. The Smithsonian Institute entered the possession of the fossils, and upon a first inspection the remains were thought to belong to a borophagine dog species called marylandica.

When Steven E. Jasinski, a doctoral student in the Dept. of Earth and Environmental Science at University of Pennsylvania, investigated the fossils, though, he found significant differences. Most striking, the Maryland fossils’ occlusal surfaces, where the top and bottom teeth meet, were significantly different that those belonging to the older borophagine. This is how eventually Jasinski and colleagues claimed a new species to science.

Borophagine dogs were very widespread in North America between 30 to 10 million years ago. These were a very successful split from the Canidae group, which up until they went extinct dominated their ecological niche. Walking all five toes, instead of four like modern canines, the borophagine were the apex predators in North America. The group was also very diverse from the massive Epicyon, which was as big as a bear to the modest Strobodon stirtoni, which mimicked cats.

The last member of the family is thought to have gone extinct some two million years ago, and C. wangi was likely among these last survivors. Ancestors to modern wolves, coyotes and foxes proved far better adapted and drove the borophagine dogs extinct.

Although  C. wangi looked pretty fierce, scientists say it wasn’t that much of a meat eater. In fact, it’s diet and habits resemble those of a bear more than a wild dog, the researchers reported in the Journal of Paleontology. 

“Based on its teeth, probably only about a third of its diet would have been meat,” Jasinski said. “It would have supplemented that by eating plants or insects, living more like a mini-bear than like a dog.”

Its bone-crushing teeth suggest it was a scavenger, as the spotted hyenas today in Africa. Given the similarities, like the spotted hyena, C. wangi might had also been a pack hunter.

Terrestrial fossils from the  Calvert Cliffs region are rare and much of what paleontologists know about the various animal species which lived around the time of C. wangi is based on marine fossils. These latest findings will serve to fit the missing pieces of what prehistoric life was like in the region. “This new dog gives us useful insight into the ecosystem of eastern North America between 12 and 13 million years ago,” Jasinski said.

Rapetosaurus krausei adult and baby, alongside a human juvenile for comparison. Credit: KRISTI CURRY ROGERS

Some sauropod babies looked like adults since they hatched and were left on their own

Sauropods, or some titanosaurs at least, were not the best parents. A recent analysis of juvenile fossils belonging to a titanosaur species called  Rapetosaurus krausei suggests babies were left to fend for themselves and find food since they hatched, with little if any weaning.

Tough dino childhood

Rapetosaurus krausei adult and baby, alongside a human juvenile for comparison. Credit: KRISTI CURRY ROGERS

Rapetosaurus krausei adult and baby, alongside a human juvenile for comparison. Credit: KRISTI CURRY ROGERS

Dinosaur juvenile fossils are very rare to find. The small bones are harder to preserve and many dinosaurs don’t spend much time as younglings to begin with. Often juvenile fossils are mistaken for the smaller bones of adults, and this is exactly what would have happened if  Kristina Curry Rogers of Macalester College in St. Paul didn’t have a trained eye. While she was still a graduate student in 2001, she was part of a team that discovered the first Rapetosaurus adult. It was rather plain to her that some of the fossils she was shifting through at  Stony Brook University belonged to a young Rapetosaurus, despite being labeled as crocodile and turtle bones.

sauropod-1

Credit: KRISTI CURRY ROGERS

Curry immediately analyzed the bones, including bones from the limbs, vertebrae and even the hip, using non-destructive techniques like CT scanning.

Fossils from a Rapetosaurus baby skeleton. Credit: KRISTI CURRY ROGERS

Fossils from a Rapetosaurus baby skeleton. Credit: KRISTI CURRY ROGERS

Like most sauropods, Rapetosaurus krausei was a huge herbivore which could grow to be up to 50 feet long. This baby, collected from Madagascar, weighed about 40 kilograms and only 35 centimeters high, or at about knee height. But that’s still quite a lot considering it was only a couple weeks old and only weighed 3.4 kilograms when it hatched from a football-sized egg.

Strikingly, these babies looked like miniature adults, staying in proportions the researchers report in Science. When human babies are born, like other mammals, their heads are disproportionally big relative to the rest of the body. Imagine how intense it would be to see a 2-months-old baby in adult proportions. Even so, it did still have cute juvenile features.

“There is no doubt that these baby titanosaurs would have had some of the features we would normally associate with cuteness or baby-ness: short snout, large eyes, big head for a body — like a puppy,” said Luis Chiappe, director of the Dinosaur Institute at the Natural History Museum of Los Angeles, who wasn’t involved in the research but praised it.

There’s no doubt these babies were  precocious, pretty much ready to walk and feed on their own since the day they hatched. It might seem cruel, but it likely came at an evolutionary advantage as the juveniles were less vulnerable to predators. A typical mother would also lay 20 to 30 eggs in a nest, so it would be difficult to wean each one. It would be interesting to find out if this was a generally defining feature of sauropods and other types of dinosaurs.