Huge dinosaurs evolved different cooling systems to combat heat stroke

Different dinosaur groups independently evolved gigantic body sizes, but they all faced the same problems of overheating and damaging their brains. Researchers from Ohio University’s Heritage College of Osteopathic Medicine show in a new article in the Anatomical Record that different giant dinosaurs solved the problem in different ways, evolving different cooling systems in different parts of the head.

“The brain and sense organs like the eye are very sensitive to temperature,” said Ruger Porter, Assistant Professor of Anatomical Instruction and lead author of the study. “Animals today often have elaborate thermoregulatory strategies to protect these tissues by shuttling hot and cool blood around various networks of blood vessels. We wanted to see if dinosaurs were doing the same things.”

Many of the famous gigantic dinosaurs — such as the long-necked sauropods or armored ankylosaurs — actually evolved those big bodies independently from smaller-bodied ancestors. “Small dinosaurs could have just run into the shade to cool off,” said study co-author Professor Lawrence Witmer, “but for those giant dinosaurs, the potential for overheating was literally inescapable. They must have had special mechanisms to control brain temperature, but what were they?”

The answer turned out to be based in physics, but still part of our everyday experience. “One of the best ways to cool things down is with evaporation,” Porter said. “The air-conditioning units in buildings and cars use evaporation, and it’s the evaporative cooling of sweat that keeps us comfortable in summer. To cool the brain, we looked to the anatomical places where there’s moisture to allow evaporative cooling, such as the eyes and especially the nasal cavity and mouth.”

To test that idea, the team looked to the modern-day relatives of dinosaurs — birds and reptiles — where studies indeed showed that evaporation of moisture in the nose, mouth, and eyes cooled the blood on its way to the brain.

Porter and Witmer obtained carcasses of birds and reptiles that had died of natural causes from zoos and wildlife rehabilitation facilities. Using a technique developed in Witmer’s lab that allows arteries and veins to show up in CT scans, they were able to trace blood flow from the sites of evaporative cooling to the brain. They also precisely measured the bony canals and grooves that conveyed the blood vessels.

“The handy thing about blood vessels is that they basically write their presence into the bones,” Porter said. “The bony canals and grooves that we see in modern-day birds and reptiles are our link to the dinosaur fossils. We can use this bony evidence to restore the patterns of blood flow in extinct dinosaurs and hopefully get a glimpse into their thermal physiology and how they dealt with heat.”

“The discovery that different dinosaurs cooled their brains in a variety of ways not only provides a window into the everyday life of dinosaurs, it also serves as an exemplar of how the physical constraints imposed by specific environmental conditions have shaped the evolution of this diverse and unique group,” said Sharon Swartz, a program director at the National Science Foundation, which funded the research. “Using a combination of technological innovation and biological expertise, these researchers were able to take a direct reading from the fossil record that provides new clues about how dinosaur skeletal form and function evolved.”

This team of current and former members of WitmerLab at Ohio University has previously looked at other cases of dinosaur physiology. In 2014 and 2018, former doctoral student Jason Bourke led projects involving Porter and Witmer on breathing and heat exchange in pachycephalosaurs and ankylosaurs, respectively. Most recently, former lab doctoral student Casey Holliday led a project with Porter and Witmer that explored blood vessels on the skull roof of T. rex and other dinosaurs that also might have had a thermoregulatory function.

The new study by Porter and Witmer is a more expansive, quantitative study that shows that “one size didn’t fit all” with regard to how large-bodied dinosaurs kept their brains cool. That is, they had different thermoregulatory strategies. The researchers looked at bony canal sizes in the dinosaurs to assess the relative importance of the different sites of evaporative cooling based on how much blood was flowing through them.

A key factor turned out to be body size. Smaller dinosaurs such as the goat-sized pachycephalosaur Stegoceras had a very balanced vascular pattern with no single cooling region being particularly emphasized. “That makes physiological sense because smaller dinosaurs have less of a problem with overheating,” Porter said. “But giants like sauropods and ankylosaurs increased blood flow to particular cooling regions of the head far beyond what was necessary to simply nourish the tissues.” This unbalanced vascular pattern allowed the thermal strategies of large dinosaurs to be more focused, emphasizing one or more cooling regions.

But although sauropods like Diplodocus and Camarasaurus and ankylosaurs like Euoplocephalus all had unbalanced vascular patterns emphasizing certain cooling regions, they still differed. Sauropods emphasized both the nasal cavity and mouth as cooling regions whereas ankylosaurs only emphasized the nose. “It’s possible that sauropods were so large — often weighing dozens of tons — that they needed to recruit the mouth as a cooling region in times of heat stress,” Porter said. “Panting sauropods may have been a common sight!”

One problem that the researchers encountered was that many of the theropod dinosaurs — such as the 10-ton T. rex — were also gigantic, but the quantitative analysis showed that they had a balanced vascular pattern, like the small-bodied dinosaurs.

“This finding had us scratching our heads until we noticed the obvious difference — theropods like Majungasaurus and T. rex had a huge air sinus in their snouts,” Witmer said. Looking closer, the researchers discovered bony evidence that this antorbital air sinus was richly supplied with blood vessels. Witmer had previously shown that air circulated through the antorbital air sinus like a bellows pump every time the animal opened and closed its mouth. “Boom! An actively ventilated, highly vascular sinus meant that we had another potential cooling region. Theropod dinosaurs solved the same problem…but in a different way,” concluded Witmer.

The researchers are now expanding the project to include other dinosaur groups such as duck-billed hadrosaurs and horned ceratopsians like Triceratops to explore how thermoregulatory strategies varied among other dinosaurs and how these strategies may have influenced their behavior and even their preferred habitats.

The research was funded by National Science Foundation (NSF) grants to Witmer (part of the Visible Interactive Dinosaur Project), as well as by the Ohio University Heritage College of Osteopathic Medicine.

Arthropods formed orderly lines 480 million years ago

Researchers studied fossilized Moroccan Ampyx trilobites, which lived 480 million years ago and showed that the trilobites had probably been buried in their positions — all oriented in the same direction. Scientists deduced that these Ampyx processions may illustrate a kind of collective behavior adopted in response to cyclic environmental disturbances.

Though our understanding of the anatomy of the earliest animals is growing ever more precise, we know next to nothing about their behaviour. Did group behaviour arise recently or is it primeval? To answer this question, researchers from the CNRS, the University of Poitiers, UBO, Claude Bernard Lyon 1 University*, Cadi Ayyad University (Marrakech, Morocco), and the University of Lausanne (Switzerland) studied fossilized Moroccan Ampyx trilobites, which lived 480 million years ago. They showed that the trilobites had probably been buried in their positions — all oriented in the same direction, in orderly lines, maintaining close contact with each other through their long spines — during storms.

By comparing this observation with the behaviour of living animals such as North American spiny lobsters, the scientists deduced that these Ampyx processions may illustrate a similar kind of collective behaviour — adopted in response to cyclic environmental disturbances like storms or to chemical signals associated with reproduction.

This example would seem to suggest that group behaviour is of ancient origin and, from an early date, likely conferred an evolutionary advantage on the first animals, allowing them to survive environmental stress and improve their reproductive chances.

*- From the Laboratoire de Géologie de Lyon: Terre, Planètes, Environnement (CNRS / ENS de Lyon / Université Claude Bernard Lyon 1), the Laboratoire Géosciences Océan (CNRS / Université Bretagne Occidentale / Université Bretagne Sud), and the Institute of Chemistry of Materials and Media of Poitiers (IC2MP (CNRS / Université de Poitiers).

Paleontologists discover complete Saurornitholestes langstoni specimen

The discovery of a nearly complete dromaeosaurid Saurornitholestes langstoni specimen is providing critical information for the evolution of theropod dinosaurs, according to new research by a University of Alberta paleontologist.

The 76-million-year-old species was long thought to be so closely related to Velociraptor from Mongolia that some researchers even called it Velociraptor langstoni — until now.

The landmark discovery was made by paleontologists Philip Currie and Clive Coy from the University of Alberta and David Evans, James and Louise Temerty Endowed Chair of Vertebrate Palaeontology at the Royal Ontario Museum. The research illustrates how Saurornitholestes differs from Velociraptor. Importantly, the research also identifies a unique tooth evolved for preening feathers and provides new evidence that the dromaeosaurid lineage from North America that includes Saurornitholestes is distinct from an Asian lineage that includes the famous Velociraptor.

“Palaeontology in general is a gigantic puzzle where most of the pieces are missing. The discovery and description of this specimen represents the recovery of many pieces of the puzzle,” said Currie, professor in the Department of Biological Sciences and Canada Research Chair in Dinosaur Paleobiology. “This ranks in the top discoveries of my career. It is pretty amazing.”

Another piece of the puzzle

Saurornitholestes is a small, feathered carnivorous dinosaur within the dromaeosaurid family (also known as “raptors”) that was previously known from fragmentary remains. Discovered by Coy in Dinosaur Provincial Park in 2014, the new skeleton is remarkably complete and exquisitely preserved, with all the bones (except for the tail) preserved in life position. The new research, which focuses on the skull, shows that the North American form has a shorter and deeper skull than the Velociraptor. At the front of the skull’s mouth, the researchers also discovered a flat tooth with long ridges, which was likely used for preening feathers. The same tooth has since been identified in Velociraptor and other dromaeosaurids.

“Because of their small size and delicate bones, small meat-eating dinosaur skeletons are exceptionally rare in the fossil record. The new skeleton is by far the most complete and best-preserved raptor skeleton ever found in North America. It’s a scientific goldmine,” said Evans.

The study also establishes a distinction between dromaeosaurids in North America and Asia. “The new anatomical information we have clearly shows that the North American dromaeosaurids are a separate lineage from the Asian dromaeosaurids, although they do have a common ancestor,” said Currie. “This changes our understanding of intercontinental movements of these animals and ultimately will help us understand their evolution.”

Future research will investigate the remainder of the skeleton as well as additional analyses on the relationships between dromaeosaurids.

T. rex used a stiff skull to eat its prey

A Tyrannosaurus rex could bite hard enough to shatter the bones of its prey. But how it accomplished this feat without breaking its own skull bones has baffled paleontologists. That’s why scientists at the University of Missouri are arguing that the T. rex’s skull was stiff much like the skulls of hyenas and crocodiles, and not flexible like snakes and birds as paleontologists previously thought.

“The T. rex had a skull that’s 6 feet long, 5 feet wide and 4 feet high, and bites with the force of about 6 tons,” said Kaleb Sellers, a graduate student in the MU School of Medicine. “Previous researchers looked at this from a bone-only perspective without taking into account all of the connections — ligaments and cartilage — that really mediate the interactions between the bones.”

Using a combination of imaging, anatomy and engineering analysis, the team observed how the roof of the mouth of the T. rex reacted to the stresses and strains from chewing by applying models of how two present day relatives of T. rex — a gecko and a parrot — chew to how the T. rex skull worked.

“Dinosaurs are like modern-day birds, crocodiles and lizards in that they inherited particular joints in their skulls from fish — ball and socket joints, much like people’s hip joints — that seem to lend themselves, but not always, to movement like in snakes,” said Casey Holliday, an associate professor of anatomy in the MU School of Medicine. “When you put a lot of force on things, there’s a tradeoff between movement and stability. Birds and lizards have more movement but less stability. When we applied their individual movements to the T. rex skull, we saw it did not like being wiggled in ways that the lizard and bird skulls do, which suggests more stiffness.”

In addition to helping paleontologists with a detailed study of the anatomy of fossilized animals, researchers believe their findings can help advance human and animal medicine by providing better models of how joints and ligaments interact.

“In humans, this can also be applied to how people’s jaws work, such as studying how the jaw joint is loaded by stresses and strains during chewing,” said Ian Cost, the lead researcher on the study. Cost is an assistant professor at Albright College and a former doctoral student in the MU School of Medicine. “In animals, understanding how those movements occur and joints are loaded will, for instance, help veterinarians better understand how to treat exotic animals such as parrots, which suffer from arthritis in their faces.”

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Journal Reference:

  1. Ian N. Cost, Kevin M. Middleton, Kaleb C. Sellers, Michael Scott Echols, Lawrence M. Witmer, Julian L. Davis, Casey M. Holliday. Palatal Biomechanics and Its Significance for Cranial Kinesis in Tyrannosaurus rexThe Anatomical Record, 2019; DOI: 10.1002/ar.24219

Dinosaur brains from baby to adult

New research by a University of Bristol palaeontology post-graduate student has revealed fresh insights into how the braincase of the dinosaur Psittacosaurus developed and how this tells us about its posture.

Psittacosaurus was a very common dinosaur in the Early Cretaceous period — 125 million years ago — that lived in eastern Asia, especially north-east China.

Hundreds of samples have been collected which show it was a beaked plant-eater, an early representative of the Ceratopsia, which had later relatives with great neck frills and face horns, such as Triceratops.

The babies hatched out as tiny, hamster-sized beasts and grew to two metres long as adults.

As they grew, the brain changed in shape, from being crammed into the back of the head, behind the huge eyes in the hatchling, to being longer, and extending under the skull roof in the adults.

The braincase also shows evidence for a change in posture as the animals grew. There is good evidence from the relative lengths of the arms and legs, that baby Psittacosaurus scurried about on all fours, but by the age of two or three, they switched to a bipedal posture, standing up on their elongate hind legs and using their arms to grab plant food.

Claire Bullar from the University of Bristol’s School of Earth Sciences led the new research which has been published this week in PeerJ.

She said: “I was excited to see that the orientation of the semi-circular canals changes to show this posture switch.

“The semi-circular canals are the structures inside our ears that help us keep balance, and the so-called horizontal semi-circular canal should be just that — horizontal — when the animal is standing in its normal posture.

“This is just what we see, with the head of Psittacosaurus pointing down and forwards when it was a baby — just right for moving on all-fours. Then, in the teen or adult, we see the head points exactly forwards, and not downwards, just right for a biped.”

Co-supervisor Dr Qi Zhao from the Institute of Vertebrate Palaeontology and Palaeoanthropology (IVPP) in Beijing, where the specimens are housed, added: “It’s great to see our idea of posture shift confirmed, and in such a clear-cut way, from the orientation of the horizontal ear canal.

“It’s also amazing to see the results of high-quality CT scanning in Beijing and the technical work by Claire to get the best 3D models from these scan data.”

Professor Michael Ryan of Carleton University, Ottawa, Canada, another collaborator, said: “This posture shift during growth from quadruped to biped is unusual for dinosaurs, or indeed any animal. Among dinosaurs, it’s more usual to go the other way, to start out as a bipedal baby, and then go down on all fours as you get really huge.

“Of course, adult Psittacosaurus were not so huge, and the shift maybe reflects different modes of life: the babies were small and vulnerable and so probably hid in the undergrowth, whereas bipedalism allowed the adults to run faster and escape their predators.”

Professor Michael Benton, also from the University of Bristol’s School of Earth Sciences and another collaborator, added: “This is a great example of classic, thorough anatomical work, but also an excellent example of international collaboration.

“The Bristol Palaeobiology Research Group has a long-standing collaboration with IVPP, and this enables the mix of excellent specimens and excellent research.

“Who would have imagined we could reconstruct posture of dinosaurs from baby to adult, and with multiple lines of evidence to confirm we got it right.”


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Extinct Caribbean bird yields DNA after 2,500 years in watery grave

Scientists have recovered the first genetic data from an extinct bird in the Caribbean, thanks to the remarkably preserved bones of a Creighton’s caracara from a flooded sinkhole on Great Abaco Island.

Studies of ancient DNA from tropical birds have faced two formidable obstacles. Organic material quickly degrades when exposed to heat, light and oxygen. And birds’ lightweight, hollow bones break easily, accelerating the decay of the DNA within.

But the dark, oxygen-free depths of a 100-foot blue hole known as Sawmill Sink provided ideal preservation conditions for the bones of Caracara creightoni, a species of large carrion-eating falcon that disappeared soon after humans arrived in the Bahamas about 1,000 years ago.

Florida Museum of Natural History postdoctoral researcher Jessica Oswald extracted and sequenced genetic material from a 2,500-year-old C. creightoni femur from the blue hole. Because ancient DNA is often fragmented or missing, Oswald had modest expectations for what she would find — maybe one or two genes. But instead, the bone yielded 98.7% of the bird’s mitochondrial genome, the set of DNA that most living things inherit only from their mothers.

“I was super excited. I would have been happy to get that amount of coverage from a fresh specimen,” said Oswald, lead author of a study describing the work and also a postdoctoral researcher at the University of Nevada, Reno. “Getting DNA from an extinct bird in the tropics is significant because it hasn’t been successful in many cases or even tried.”

The mitochondrial genome showed that C. creightoni is closely related to the two remaining caracara species alive today: the crested caracara, Caracara cheriway, and the southern caracara, Caracara plancus. The three species last shared a common ancestor between 1.2 and 0.4 million years ago.

At least six species of caracara once cleaned carcasses and picked off small prey in the Caribbean. But the retreat of glaciers 15,000 years ago and the resulting rise in sea levels triggered extinctions of many birds, said David Steadman, Florida Museum curator of ornithology.

C. creightoni managed to survive the sweeping climatic changes, but the arrival of people on the islands ultimately heralded the species’ demise, as the tortoises, crocodiles, iguanas and rodents that the caracara depended on for food swiftly disappeared.

“This species would still be flying around if it weren’t for humans,” Steadman said. “We’re using ancient DNA to study what should be modern biodiversity.”

Today, the islands host only a fraction of the wildlife that once flourished in the scrubland, forests and water. But blue holes like Sawmill Sink can offer a portal into the past. Researchers have collected more than 10,000 fossils from the sinkhole, representing nearly 100 species, including crocodiles, tortoises, iguanas, snakes, bats and more than 60 species of birds.

Sawmill Sink’s rich store of fossils was discovered by cave diver Brian Kakuk in 2005 in his quest for horizontal passages in the limestone. The hole was not a popular diving spot: Thirty feet below the surface lay a 20-foot-thick layer of saturated hydrogen sulfide, an opaque mass that not only smells of rotten egg, but also reacts with the freshwater above it to form sulfuric acid, which causes severe chemical burns.

After multiple attempts, Kakuk, outfitted with a rebreather system and extra skin protection, punched through the hydrogen sulfide. His lamp lit up dozens of skulls and bones on the blue hole’s floor.

Soon after, Kakuk and fellow cave diver Nancy Albury began an organized diving program in Sawmill Sink.

“This was found by someone who recognized what it was and never moved anything until it was all done right,” Steadman said.

Though the hydrogen sulfide layer presented a foul problem for divers, it provided excellent insulation for the fossils below, blocking UV light and oxygen from reaching the lower layer of water. Among the crocodile skulls and tortoise shells were the C. creightoni bones, including an intact skull.

“For birds, having an entire head of an extinct species from a fossil site is pretty mind-blowing,” Oswald said. “Because all the material from the blue hole is beautifully preserved, we thought at least some DNA would probably be there.”

Since 2017, Oswald has been revitalizing the museum’s ancient DNA laboratory, testing methods and developing best practices for extracting and analyzing DNA from fossils and objects that are hundreds to millions of years old.

Ancient DNA is a challenging medium because it’s in the process of degradation. Sometimes only a minute quantity of an animal’s original DNA — or no DNA at all — remains after bacteria, fungi, light, oxygen, heat and other environmental factors have broken down an organism.

“With ancient DNA, you take what you can get and see what works,” Oswald said. “Every bone has been subjected to slightly different conditions, even relative to other ones from the same site.”

To maximize her chance of salvaging genetic material, Oswald cleans a bone, freezes it with liquid nitrogen and then pulverizes it into powder with a rubber mallet.

“It’s pretty fun,” she said.

While previous studies required large amounts of bone, Oswald’s caracara work showed ancient DNA could be successfully recovered at a smaller scale.

“This puts an exclamation point on what’s possible with ancient DNA,” said Robert Guralnick, Florida Museum curator of bioinformatics. “We have new techniques for looking at the context of evolution and extinction. Beyond the caracara, it’s cool that we have an ancient DNA lab that’s going to deliver ways to look at questions not only from the paleontological perspective, but also at the beginnings of a human-dominated planet.”

Steadman, who has spent decades researching modern and extinct biodiversity in the Caribbean, said some questions can only be answered with ancient DNA.

“By understanding species that weren’t able to withstand human presence, it helps us better appreciate what we have left — and not just appreciate it, but understand that when these species evolved, there were a lot more things running and flying around than we have today.”

Other co-authors are Julia Allen of the University of Nevada, Reno; Kelsey Witt of the University of California, Merced; Ryan Folk of the Florida Museum and Nancy Albury of the National Museum of the Bahamas.


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Researchers discover oldest fossil forest in Asia

The Devonian period, which was 419 million to 359 million years ago, is best known for Tiktaalik, the lobe-finned fish that is often portrayed pulling itself onto land. However, the “age of the fishes,” as the period is called, also saw evolutionary progress in plants. Researchers reporting August 8 in the journal Current Biology describe the largest example of a Devonian forest, made up of 250,000 square meters of fossilized lycopsid trees, which was recently discovered near Xinhang in China’s Anhui province. The fossil forest, which is larger than Grand Central Station, is the earliest example of a forest in Asia.

Lycopsids found in the Xinhang forest resembled palm trees, with branchless trunks and leafy crowns, and grew in a coastal environment prone to flooding. These lycopsid trees were normally less than 3.2 meters tall, but the tallest was estimated at 7.7 meters, taller than the average giraffe. Giant lycopsids would later define the Carboniferous period, which followed the Devonian, and become much of the coal that is mined today. The Xinhang forest depicts the early root systems that made their height possible. Two other Devonian fossil forests have been found: one in the United States, and one in Norway.

“The large density as well as the small size of the trees could make Xinhang forest very similar to a sugarcane field, although the plants in Xinhang forest are distributed in patches,” says Deming Wang, a professor in the School of Earth and Space Sciences at Peking University, co-first author on the paper along with Min Qin of Linyi University. “It might also be that the Xinhang lycopsid forest was much like the mangroves along the coast, since they occur in a similar environment and play comparable ecologic roles.”

The fossilized trees are visible in the walls of the Jianchuan and Yongchuan clay quarries, below and above a four-meter thick sandstone bed. Some fossils included pinecone-like structures with megaspores, and the diameters of fossilized trunks were used to estimate the trees’ heights. The authors remarked that it was difficult to mark and count all the trees without missing anything.

“Jianchuan quarry has been mined for several years and there were always some excavators working at the section. The excavations in quarries benefit our finding and research. When the excavators stop or left, we come close to the highwalls and look for exposed erect lycopsid trunks,” says Wang, who, with Qin, found the first collection of fossil trunks in the mine in 2016. “The continuous finding of new in-situ tree fossils is fantastic. As an old saying goes: the best one is always the next one.”

This work was supported by The National Natural Science Foundation of China.


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NZ big bird a whopping ‘squawkzilla’

Australasian palaeontologists have discovered the world’s largest parrot, standing up to 1m tall with a massive beak able to crack most food sources.

The new bird has been named Heracles inexpectatus to reflect its Herculean myth-like size and strength — and the unexpected nature of the discovery.

“New Zealand is well known for its giant birds,” says Flinders University Associate Professor Trevor Worthy. “Not only moa dominated avifaunas, but giant geese and adzebills shared the forest floor, while a giant eagle ruled the skies.

“But until now, no-one has ever found an extinct giant parrot — anywhere.”

The NZ fossil is approximately the size of the giant ‘dodo’ pigeon of the Mascarenes and twice the size of the critically endangered flightless New Zealand kakapo, previously the largest known parrot.

Like the kakapo, it was a member of an ancient New Zealand group of parrots that appear to be more primitive than parrots that thrive today on Australia and other continents.

Experts from Flinders University, UNSW Sydney and Canterbury Museum in New Zealand estimate Heracles to be 1 m tall, weighing about 7 kg.

The new parrot was found in fossils up to 19 million years old from near St Bathans in Central Otago, New Zealand, in an area well known for a rich assemblage of fossil birds from the Miocene period.

“We have been excavating these fossil deposits for 20 years, and each year reveals new birds and other animals,” says Associate Professor Worthy, from the Flinders University Palaeontology Lab.

“While Heracles is one of the most spectacular birds we have found, no doubt there are many more unexpected species yet to be discovered in this most interesting deposit.”

“Heracles, as the largest parrot ever, no doubt with a massive parrot beak that could crack wide open anything it fancied, may well have dined on more than conventional parrot foods, perhaps even other parrots,” says Professor Mike Archer, from the UNSW Sydney Palaeontology, Geobiology and Earth Archives (PANGEA) Research Centre.

“Its rarity in the deposit is something we might expect if it was feeding higher up in the food chain,” he says, adding parrots “in general are very resourceful birds in terms of culinary interests.”

“New Zealand keas, for example, have even developed a taste for sheep since these were introduced by European settlers in 1773.”

Birds have repeatedly evolved giant species on islands. As well as the dodo, there has been another giant pigeon found on Fiji, a giant stork on Flores, giant ducks in Hawaii, giant megapodes in New Caledonia and Fiji, giant owls and other raptors in the Caribbean.

Heracles lived in a diverse subtropical forest where many species of laurels and palms grew with podocarp trees.

“Undoubtedly, these provided a rich harvest of fruit important in the diet of Heracles and the parrots and pigeons it lived with. But on the forest floor Heracles competed with adzebills and the forerunners of moa,” says Professor Suzanne Hand, also from UNSW Sydney.

“The St Bathans fauna provides the only insight into the terrestrial birds and other animals that lived in New Zealand since dinosaurs roamed the land more than 66 million years ago,” says Paul Scofield, Senior Curator at Canterbury Museum, Christchurch.

Canterbury Museum research curator Vanesa De Pietri says the fossil deposit reveals a highly diverse fauna typical of subtropical climates with crocodilians, turtles, many bats and other mammals, and over 40 bird species.

“This was a very different place with a fauna very unlike that which survived into recent times,” she says.

This research was funded by the Australian Research Council and supported by the Marsden Fund Council from Government funding, managed by Royal Society Te Ap?rangi.


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New species of dinosaur discovered after lying misidentified in fossil vaults for 30 years

A PhD student of the University of the Witwatersrand, South Africa, has discovered a new dinosaur species in the University’s vaults, after it has been laying misidentified in a collection for 30 years.

The team of scientists, led by PhD Student Kimberley Chapelle, recognised that the dinosaur was not only a new species of sauropodomorph, but an entirely new genus. The specimen has now been named Ngwevu intloko which means “grey skull” in the Xhosa language, chosen to honour South Africa’s heritage. She was joined in the research by her PhD supervisors: Prof Jonah Choiniere (Wits), Dr Jennifer Botha (National Museum Bloemfontein), and Professor Paul Barrett (Natural History Museum, London). Together, Kimberley and these world-leading researchers have been improving knowledge of South African palaeontology for the last six years. The dinosaur has been described in the academic journal, PeerJ.

Professor Paul Barrett, Chapelle’s PhS supervisor and researcher at the Natural History Museum in the UK explains, “This is a new dinosaur that has been hiding in plain sight.” “The specimen has been in the collections in Johannesburg for about 30 years, and lots of other scientists have already looked at it. But they all thought that it was simply an odd example of Massospondylus.”

Massospondylus was one of the first dinosaurs to reign at the start of the Jurassic period. Regularly found throughout southern Africa, these animals belonged to a group called the sauropodomorphs and eventually gave rise to the sauropods, a group containing the Natural History Museum’s iconic dinosaur cast Dippy. Researchers are now starting to look closer at many of the supposed Massospondylus specimens, believing there to be much more variation than first thought.

Kimberley Chapelle explains why the team were able to confirm that this specimen was a new species, “In order to be certain that a fossil belongs to a new species, it is crucial to rule out the possibility that it is a younger or older version of an already existing species. This is a difficult task to accomplish with fossils because it is rare to have a complete age series of fossils from a single species. Luckily, the most common South African dinosaur Massospondylus has specimens ranging from embryo to adult. Based on this, we were able to rule out age as a possible explanation for the differences we observed in the specimen now named Ngwevu intloko.”

The new dinosaur has been described from a single fairly complete specimen with a remarkably well-preserved skull. The new dinosaur was bipedal with a fairly chunky body, a long slender neck and a small, boxy head. It would have measured three metres from the tip of its snout to the end of its tail and was likely an omnivore, feeding on both plants and small animals.

The findings will help scientists better understand the transition between the Triassic and Jurassic period, around 200 million years ago. Known as a time of mass extinction it now seems that more complex ecosystems were flourishing in the earliest Jurassic than previously thought.

“This new species is interesting,” says Prof Barrett, “because we thought previously that there was really only one type of sauropodomorph living in South Africa at this time. We now know there were actually six or seven of these dinosaurs in this area, as well as variety of other dinosaurs from less common groups. It means that their ecology was much more complex than we used to think. Some of these other sauropodomorphs were like Massospondylus, but a few were close to the origins of true sauropods, if not true sauropods themselves.”

This work shows the value of revisiting specimens in museum collections, as many news species are probably sitting unnoticed in cabinets around the world.


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A voracious Cambrian predator, Cambroraster, is a new species from the Burgess Shale

Palaeontologists at the Royal Ontario Museum and University of Toronto have uncovered fossils of a large new predatory species in half-a-billion-year-old rocks from Kootenay National Park in the Canadian Rockies. This new species has rake-like claws and a pineapple-slice-shaped mouth at the front of an enormous head, and it sheds light on the diversity of the earliest relatives of insects, crabs, spiders, and their kin. The findings were announced July 31, 2019, in a study published in Proceedings of the Royal Society B.

Reaching up to a foot in length, the new species, named Cambroraster falcatus, comes from the famous 506-million-year-old Burgess Shale. “Its size would have been even more impressive at the time it was alive, as most animals living during the Cambrian Period were smaller than your little finger,” said Joe Moysiuk, a graduate student based at the Royal Ontario Museum who led the study as part of his PhD research in Ecology & Evolutionary Biology at the University of Toronto. Cambrorasterwas a distant cousin of the iconic Anomalocaris, the top predator living in the seas at that time, but it seems to have been feeding in a radically different way,” continued Moysiuk.

The name Cambroraster refers to the remarkable claws of this animal, which bear a parallel series of outgrowths, looking like forward-directed rakes. “We think Cambroraster may have used these claws to sift through sediment, trapping buried prey in the net-like array of hooked spines,” added Jean-Bernard Caron, Moysiuk’s supervisor and the Richard M. Ivey Curator of Invertebrate Palaeontology at the Royal Ontario Museum.

With the interspace between the spines on the claws at typically less than a millimeter, this would have enabled Cambroraster to feed on very small organisms, although larger prey could also likely be captured, and ingested into the circular tooth-lined mouth. This specialized mouth apparatus is the namesake of the extinct group Radiodonta, which includes both Cambroraster and Anomalocaris. Radiodonta is considered to be one of the earliest offshoots of the arthropod lineage (today including all animals with an exoskeleton, a segmented body and jointed limbs).

The second part of the species name falcatus was given in tribute to another of Cambroraster‘s distinctive features: the large shield-like carapace covering its head, which is shaped like the Millennium Falcon spaceship from the Star Wars films. “With its broad head carapace with deep notches accommodating the upward facing eyes, Cambroraster resembles modern living bottom-dwelling animals like horseshoe crabs. This represents a remarkable case of evolutionary convergence in these radiodonts,” Moysiuk explained. Such convergence is likely reflective of a similar environment and mode of life — like modern horseshoe crabs, Cambroraster may have used its carapace to plough through sediment as it fed.

Perhaps even more astonishing is the large number of specimens recovered. “The sheer abundance of this animal is extraordinary,” added Dr. Caron, who is also an Assistant Professor in Ecology & Evolutionary Biology and Earth Sciences at the University of Toronto, and the leader of the field expeditions that unearthed the new fossils. “Over the past few summers we found hundreds of specimens, sometimes with dozens of individuals covering single rock slabs.”

Based on over a hundred exceptionally well-preserved fossils now housed at the Museum, researchers were able to reconstruct Cambroraster in unprecedented detail, revealing characteristics that had not been seen before in related species.

“The radiodont fossil record is very sparse; typically, we only find scattered bits and pieces. The large number of parts and unusually complete fossils preserved at the same place are a real coup, as they help us to better understand what these animals looked like and how they lived,” said Dr. Caron. “We are really excited about this discovery. Cambroraster clearly illustrates that predation was a big deal at that time with many kinds of surprising morphological adaptations.”

Fossils from the Cambrian period, particularly from sites like the Burgess Shale, record a dramatic “explosion” of biodiversity at this time, culminating in the evolution of most of the major groups of animals that survive today. But, the story has far more intricacy than a straight line leading from simple ancestors to the vast diversity of modern species. “Far from being primitive, radiodonts show us that at the very outset of complex ecosystems on Earth, early representatives of the arthropod lineage rapidly radiated to play a wide array of ecological roles,” remarked Moysiuk.

The fossils were found at several sites in the Marble Canyon area in Kootenay National Park, British Columbia, which have been discovered by ROM-led field teams since 2012, with some of the key specimens unearthed just last summer. These sites are about 40 kilometers away from the original Burgess Shale fossil site in Yoho National Park that was first discovered in 1909. What is also exciting for researchers is the realization that there is a large new area in northern Kootenay National Park worth scientific exploration, holding the potential for the discovery of many more new species.

The Burgess Shale fossil sites are located within Yoho and Kootenay National Parks and are managed by Parks Canada. Parks Canada is proud to work with leading scientific researchers to expand our knowledge and understanding of this key period of earth history and to share these sites with the world through award-winning guided hikes. The Burgess Shale was designated a UNESCO World Heritage Site in 1980 due to its outstanding universal value, and is now part of the larger Canadian Rocky Mountain Parks World Heritage Site.

The discovery and study of Cambroraster will be profiled in the upcoming CBC’s The Nature of Things episode “First Animals” airing October 18, 2019 at 9 p.m. and on the free CBC Gem streaming service. These and other Burgess Shale specimens will be showcased in a brand-new gallery at the Royal Ontario Museum, the Willner Madge Gallery of the Dawn of Life, expected to open in 2021. Starting this summer, select specimens of Cambroraster will be put on display in the New Research case within the current temporary Willner Madge Gallery, Dawn of Life Preview exhibition.

Major funding support for the research and field work came from the Natural Sciences and Engineering Research Council of Canada (Discovery Grant #341944), the Royal Ontario Museum, the National Geographic Society (#9475-14), the Swedish Research Council (to Michael Streng), the National Science Foundation (NSF-EAR-1554897) and Pomona College (to Robert R. Gaines). Moysiuk’s PhD research is also supported by an NSERC Canada Graduate Scholarship (CGSM).


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