Ancient reptiles detached tails to escape

This 2015 video is called Treasure Trove of Permian Fossils Discovered | Prehistoric News.

From the University of Toronto in Canada:

Ancient reptile Captorhinus could detach its tail to escape predator’s grasp

March 6, 2018

Summary: A new study shows how a group of small reptiles who lived 289 million years ago could detach their tails to escape the grasp of their would-be predators — the oldest known example of such behavior.

Imagine that you’re a voracious carnivore who sinks its teeth into the tail of a small reptile and anticipates a delicious lunch, when, in a flash, the reptile is gone and you are left holding a wiggling tail between your jaws.

A new study by the University of Toronto Mississauga research team led by Professor Robert Reisz and PhD student Aaron LeBlanc, published March 5 in the open source journal, Scientific Reports, shows how a group of small reptiles who lived 289 million years ago could detach their tails to escape the grasp of their would-be predators — the oldest known example of such behaviour. The reptiles, called Captorhinus, weighed less than 2 kilograms and were smaller than the predators of the time. They were abundant in terrestrial communities during the Early Permian period and are distant relatives of all the reptiles today.

As small omnivores and herbivores, Captorhinus and its relatives had to scrounge for food while avoiding being preyed upon by large meat-eating amphibians and ancient relatives of mammals. “One of the ways captorhinids could do this,” says first author LeBlanc, “was by having breakable tail vertebrae.” Like many present-day lizard species, such as skinks, that can detach their tails to escape or distract a predator, the middle of many tail vertebrae had cracks in them.

It is likely that these cracks acted like the perforated lines between two paper towel sheets, allowing vertebrae to break in half along planes of weakness. “If a predator grabbed hold of one of these reptiles, the vertebra would break at the crack and the tail would drop off, allowing the captorhinid to escape relatively unharmed,” says Reisz, a Distinguished Professor of Biology at the University of Toronto Mississauga.

The authors note that being the only reptiles with such an escape strategy may have been a key to their success, because they were the most common reptiles of their time, and by the end of the Permian period 251 million years ago, captorhinids had dispersed across the ancient supercontinent of Pangaea. This trait disappeared from the fossil record when Captorhinus died out; it re-evolved in lizards only 70 million years ago.

They were able to examine more than 70 tail vertebrae — both juveniles and adults — and partial tail skeletons with splits that ran through their vertebrae. They compared these skeletons to those of other reptilian relatives of captorhinids, but it appears that this ability is restricted to this family of reptiles in the Permian period.

Using various paleontological and histological techniques, the authors discovered that the cracks were features that formed naturally as the vertebrae were developing. Interestingly, the research team found that young captorhinids had well-formed cracks, while those in some adults tended to fuse up. This makes sense, since predation is much greater on young individuals and they need this ability to defend themselves.

This study was possible thanks to the treasure trove of fossils available at the cave deposits near Richards Spur, Oklahoma.


Baby bird from dinosaur age discovered

Overview photographs of the slab and counterslab of the newly discovered baby bird fossil MPCM-LH-26189. Slab a is on the left, slab b, on the right. The two red boxes indicate the localisation of the areas analysed histologically. Abbreviations: An: angular, Ar: articular, CaV: caudal vertebrae, CeV: cervical vertebrae, Co: coracoid, De: dentary, DoV: dorsal vertebrae, Fe: femur, Fr: frontal, Ga: gastralium, Hu: humerus, Hy: hyoid, Is: ischium, Ju: jugal, MiMC: minor metacarpal, Pu: pubis, Qu: quadrate, Ra: radius, Ri: rib, Sa: surangular, Sp: splenial, SaV: sacral vertebrae, SR: sclerotic ring, St: sternum, Ti: tibia, Ul: ulna

From the University of Manchester in England:

127-million-year-old baby bird fossil sheds light on avian evolution

March 5, 2018

The tiny fossil of a prehistoric baby bird is helping scientists understand how early avians came into the world in the Age of Dinosaurs.

The fossil, which dates back to the Mesozoic Era (250-65 million years ago), is a chick from a group of prehistoric birds called, Enantiornithes. Made up of a nearly complete skeleton, the specimen is amongst the smallest known Mesozoic avian fossils ever discovered.

It measures less than five centimetres — smaller than the little finger on an average human hand — and would have weighed just three ounces when it was alive. What makes this fossil so important and unique is the fact it died not long after its birth. This is a critical stage in a bird’s skeletal formation. That means this bird’s extremely short life has given researchers a rare chance to analyse the species’ bone structure and development.

Studying and analysing ossification — the process of bone development — can explain a lot about a young bird’s life the researchers say. It can help them understand everything from whether it could fly or if it needed to stay with its parents after hatching or could survive on its own.

The lead author of the study, Fabien Knoll, from The University of Manchester’s Interdisciplinary Centre for Ancient Life (ICAL), School of Earth and Environmental Sciences, and the ARAID — Dinopolis in Spain explains: ‘The evolutionary diversification of birds has resulted in a wide range of hatchling developmental strategies and important differences in their growth rates. By analysing bone development we can look at a whole host of evolutionary traits.’

With the fossil being so small the team used synchrotron radiation to picture the tiny specimen at a ‘submicron’ level, observing the bones’ microstructures in extreme detail.

Knoll said: ‘New technologies are offering palaeontologists unprecedented capacities to investigate provocative fossils. Here we made the most of state-of-the-art facilities worldwide including three different synchrotrons in France, the UK and the United States.’

The researchers found the baby bird’s sternum (breastplate bone) was still largely made of cartilage and had not yet developed into hard, solid bone when it died, meaning it wouldn’t have been able to fly.

The patterns of ossification observed in this and the other few very young enantiornithine birds known to date also suggest that the developmental strategies of this particular group of ancient avians may have been more diverse than previously thought.

However, the team say that its lack of bone development doesn’t necessarily mean the hatchling was over reliant on its parents for care and feeding, a trait known as being ‘altricial’. Modern day species like love birds are highly dependent on their parents when born. Others, like chickens, are highly independent, which is known as ‘precocial’. Although, this is not a black-and-white issue, but rather a spectrum, hence the difficulty in clarifying the developmental strategies of long gone bird species.

Luis Chiappe, from the LA Museum of Natural History and study’s co-author added: ‘This new discovery, together with others from around the world, allows us to peek into the world of ancient birds that lived during the age of dinosaurs. It is amazing to realise how many of the features we see among living birds had already been developed more than 100 million years ago.’

Ankylosaur dinosaur fossils, new theory

This 2016 video is called Interesting Facts About Ankylosaurus.

From the Canadian Museum of Nature:

Flipside of a dinosaur mystery: ‘Bloat-and-float’ explains belly-up ankylosaur fossils

February 28, 2018

Summary: Why are fossil remains of ankylosaurs — armored ‘tanks of the Cretaceaous’ — usually found belly-up? A paleontologist proposes the explanation is ‘bloat-and-float’, where the dead dinos would float downstream, bloat, flip upside down, and be fossilized that way.

A scientist with the Canadian Museum of Nature has answered a long-standing mystery about why fossils of ankylosaurs — the “armoured tanks” of the dinosaur world — are mainly found belly-side up. In doing so, he has ruled out three other competing theories involving clumsiness, predation, and the effects of bloating as seen in armadillo roadkills.

Palaeontologist Dr. Jordan Mallon says the evidence points to a phenomenon called “bloat-and-float,” whereby the bloating carcasses of ankylosaurs would end up in a river, flip belly-side up due to the weight of their heavy armour, and then float downstream. The remains would wash ashore, where decomposition and then fossilization would seal the dinosaur remains in their upside-down death pose.

“Textbooks have touted that ankylosaur fossils are usually found upside down, but no one has gone back and checked the records to make sure that’s the case,” explains Mallon. The observations date from the 1930s. Indeed, the fossils of two star ankylosaurs described in 2017, Borealopelta from Alberta and Zuul from Montana, were found upside down.

Mallon examined 32 ankylosaur fossils from Alberta (of which 26 were found belly up), photos of specimens, field notes, and other signs such as erosion of the exposed surface, sun bleaching, and the presence of lichens.

The results are published in the online journal Palaeogeography, Palaeoclimatology, Palaeoecology. Collaborators included armadillo experts Drs. Colleen McDonough and Jim Loughry of Valdosta State University in Georgia, and Dr. Don Henderson, with Drumheller Alberta’s Royal Tyrrell Museum of Palaeontology.

Mallon ruled out three other theories before settling on “bloat-and-float” to explain the preponderance of the belly-up remains.

“One idea was that ankylosaurs were simply clumsy, tripping over themselves or rolling down hills and ending up dying that way,” he says. But since ankylosaurs existed for about 100 million years, clumsy habits would not fit with their apparent evolutionary success.

Another theory was that ankylosaurs were prey for carnivores, such as hungry tyrannosaurids, which would flip the armoured dinosaurs onto their backs to get at the soft underbelly. “If this was true, we would expect to see signs of bite marks, especially on upside-down ones, but we saw marks on only one specimen”, explains Mallon. “Since they were armoured, it makes sense that ankylosaurs were not regularly preyed upon, and the fossil evidence in museum collections supports this.”

The third idea, proposed in the 1980s, is an analogy to what happens with some armadillo roadkills — as the carcass rots and bloats, gas accumulates, and the limbs would splay out, eventually rolling the animal onto its back.

The challenge was to test this hypothesis. Enter McDonough and Loughry who are experts on modern armadillos, which also have an armoured shell. Over the summer of 2016, they studied 174 examples of dead armadillo. “Sure enough, the data show that they do not occur more often on their backs,” says Mallon. The pair even examined dead armadillos placed in plexiglass cases in their backyard to keep away scavengers. Regardless of the positioning of the carcasses, bloating did not cause them to roll over onto their backs.

That left the “bloat-and-float” hypothesis as the most likely explanation for the presence of upside-down fossils. To study this, Mallon turned to computer simulations developed by Dr. Don Henderson, who specializes in the floating behaviour of animals in water.

Ankylosaur fossils in North America are found in river channel deposits, and in the Late Cretaceous Period these animals would have been living along a coastline of what is known as the Western Interior Seaway.

“We designed these models of ankylosaurs, both clubless and clubbed, and looked at their floating behavior,” explains Mallon. The computer modelling showed that the animals would tend to flip upside down quite easily in water. Nodosaurids, which are ankylosaurs with no tail clubs, would flip most easily at the slightest tilt; the ankyosaurids (with clubbed tails), were more stable but could still be flipped.

“So ‘bloat-and-float'” fits with their known environment, and this research helps inform about the transport behavior of dead dinosaurs, which is important to know when studying fossil ecosystems. Ultimately, this is a classic case study of the scientific method: examining alternative hypotheses, finding ways to test them, and ruling them out one-by-one. What you are left with at the end is the most likely explanation.”

Fossil turtle discovery in Tennessee, USA

This video from the USA says about itself:

22 February 2018

Earlier this February (2018) a research paper was put out by Steven E Jasinsky describing a new species of ancient turtle discovered at the Gray Fossil Site in East Tennessee. This turtle in particular was named after our lab and field manager Shawn Haugrud. Here he is presenting a few specimens of this fossil.

From the University of Pennsylvania in the USA:

Fossil turtle species, 5.5 million years old, sheds light on invasive modern relatives

February 26, 2018

A University of Pennsylvania paleontologist has described a 5.5 million-year-old fossil species of turtle from eastern Tennessee. It represents a new species of the genus Trachemys, commonly known as sliders, which are frequently kept as pets today.

Steven Jasinski, author of the new study, is a doctoral student at the University of Pennsylvania and acting curator of paleontology and geology at the State Museum of Pennsylvania. He is completing his Ph.D. at Penn under Peter Dodson, a professor of paleontology in the Department of Earth and Environmental Science in the School of Arts and Sciences and a professor of anatomy in the School of Veterinary Medicine.

The study investigated a fossil turtle found around the Miocene-Pliocene boundary in the Gray Fossil Site, an area rich with fossils in eastern Tennessee near East Tennessee State University, where Jasinski completed his master’s degree. The site represents an ancient sinkhole surrounded by a forest from which dozens of fossil animal species have been characterized, including new species of red panda, Eurasian badger, kinosternid turtle, and colubrid snake.

Thorough examination of the dozens of turtle fossils from the site revealed important differences between this turtle and other known fossil and living species. Jasinski named the fossil turtle Trachemys haugrudi, after Shawn Haugrud, the lab and field manager and lead preparer at the Gray Fossil Site.

“Shawn has spent an incredible number of hours working on these specimens”, Jasinski said. “He cleaned and prepared the fossils and was able to essentially glue this turtle back to life, giving me numerous nearly complete turtle shells to use in this research. Without all that time and effort, I wouldn’t have been able to determine nearly as much about this turtle as I did.

“Shawn also didn’t do this work alone, as numerous other people including volunteers worked on these fossils and got them prepared so that I could complete my research. They really did all the hard work, and I was then able to determine why it was new and what its implications are” he said.

Turtles are best known for their shells, and indeed it is this feature of their anatomy that is commonly found as fossils. Yet the fossil shells are typically found in broken pieces. Often gaps or holes remain, or only single small pieces are found, and the whole must be inferred from other information, including other fossil and living creatures.

“It is extremely rare to get more complete fossils”, Jasinski said, “but Trachemys haugrudi, commonly called Haugrud’s slider turtle, provides me with dozens of shells, and several are nearly complete.”

Haugrud’s slider turtle was a fairly small turtle, not more than approximately 10 inches (25 cm) in total shell length, smaller than the modern-day red-eared slider turtle, Trachemys scripta elegans. Red-eared slider turtles are commonly purchased as pets, though they can grow large, and some owners release them into the wild. As a result, though native to the southeastern United States, red-eared sliders have become one of the most invasive animal species in the world today, found on every continent except Antarctica.

“People tend to see all turtles as similar and release them into whatever pond or river is close by when they no longer want to care for them”, Jasinski said. “Once released, however, they often outcompete native species. It is a problem that scientists are still dealing with.”

As part of the study, Jasinski sought to determine where Trachemys haugrudi was positioned in the evolution of similar turtles both within the genus and in related genera. He performed a phylogenetic analysis, a method that compares shapes and features of different species to determine how similar or dissimilar and therefore how closely related they may be. He found Haugrud’s to be most closely related to a group of fossil Trachemys turtles from Florida and next most closely related to a distinct group of fossil Trachemys from the midwestern U.S. Together, these fossil Trachemys form a closely related group situated within other still-living species of Trachemys.

Today, distinct, closely-related groups of Trachemys species dwell in Mexico, Central and South America, and the Caribbean. Jasinski’s investigation, along with other information from previous studies, indicates that one group evolved in Mexico and Central and South America and evolved into different species within this geographic area, and another group evolved separately in the Caribbean.

Species from the U.S., including the red-eared slider turtle, are found near the base of their “branch” of the Trachemys family tree; their fossil ancestors are still waiting to be discovered. The fossil Trachemys species in Jasinski’s analysis are on a distinct part of the Trachemys tree, and current understanding suggests that they did not give rise to the modern species living today.

The findings imply that there was once much greater diversity in Trachemys turtles than exists today. It seems that many of the ancient slider species died out without leaving any direct descendents, perhaps because they lacked the ability to adapt to different environments.

“While Trachemys turtle species are considered plastic, implying they can adapt to and live in many environments, this adaptive lifestyle may be a relatively newer characteristic of these turtles”, Jasinski said. “More fossils are needed to better understand if this aspect of their evolution is a recent addition.”

To get a handle on invasive turtles, understanding more about their ancient relatives could only be helpful, Jasinski said.

“Trachemys haugrudi helps provide more information on Trachemys and begins to offer us insights into the evolution of an animal that has become a problematic invader in many areas of the world”, he said. “Understanding how something evolved into its present form may help us understand why an animal is so adaptive and good at invading new areas and outcompeting native species. If we can see that Trachemys today are especially adaptive because evolution has allowed them to become more generalized through time, we can use that information to determine where they may invade, what species they may outcompete and what we can do to counteract those invasions or help native species compete against them.”

Jasinski is undertaking further study into the fossil species of not only Trachemys but other turtles within the family Emydidae, which includes Trachemys. He hopes that further data and fossils will help shed light on other turtle species and provide a clearer understanding of the evolution of this group of mainly New World turtles.

The study was supported by the National Science Foundation (Grant 0958985 to Steven Wallace and the Gray Fossil Site), Office of Research and Sponsored Programs at East Tennessee State University, Don Sundquist Center of Excellence in Paleontology, State Museum of Pennsylvania, and Department of Earth and Environmental Science at the University of Pennsylvania.

Elephant evolution, new study

This 2017 video is called Evolution of Elephants (Prehistoric to Today).

From McMaster University in Canada:

Complete genomes of extinct and living elephants sequenced

Findings point to highly complex relationships

February 26, 2018

An international team of researchers has produced one of the most comprehensive evolutionary pictures to date by looking at one of the world’s most iconic animal families — namely elephants, and their relatives mammoths and mastodons-spanning millions of years.

The team of scientists-which included researchers from McMaster, the Broad Institute of MIT and Harvard, Harvard Medical School, Uppsala University, and the University of Potsdam-meticulously sequenced 14 genomes from several species: both living and extinct species from Asia and Africa, two American mastodons, a 120,000-year-old straight-tusked elephant, and a Columbian mammoth.

The study, published in the Proceedings of the National Academy of Science, sheds light on what scientists call a very complicated history, characterized by widespread interbreeding. They caution, however, the behaviour has virtually stopped among living elephants, adding to growing fears about the future of the few species that remain on earth.

“Interbreeding may help explain why mammoths were so successful over such diverse environments and for such a long time, importantly this genomic data also tells us that biology is messy and that evolution doesn’t happen in an organized, linear fashion”, says evolutionary geneticist Hendrik Poinar, one of the senior authors on the paper and Director of the McMaster Ancient DNA Centre and principal investigator at the Michael G. DeGroote Institute for Infectious Research.

“The combined analysis of genome-wide data from all these ancient elephants and mastodons has raised the curtain on elephant population history, revealing complexity that we were simply not aware of before”, he says.

A detailed DNA analysis of the ancient straight-tusked elephant, for example, showed that it was a hybrid with portions of its genetic makeup stemming from an ancient African elephant, the woolly mammoth and present-day forest elephants.

“This is one of the oldest high-quality genomes that currently exists for any species”, said Michael Hofreiter at the University of Potsdam in Germany, a co-senior author who led the work on the straight-tusked elephant.

Researchers also found further evidence of interbreeding among the Columbian and woolly mammoths, which was first reported by Poinar and his team in 2011. Despite their vastly different habitats and sizes, researchers believe the woolly mammoths encountered Columbians mammoths at the boundary of glacial and in the more temperate ecotones of North America.

Strikingly, scientists found no genetic evidence of interbreeding among two of the world’s three remaining species, the forest and savanna elephants, suggesting they have lived in near-complete isolation for the past 500,000 years, despite living in neighbouring habitats.

“There’s been a simmering debate in the conservation communities about whether African savannah and forest elephants are two different species”, said David Reich, another co-senior author at the Broad Institute who is also a professor at the Department of Genetics at Harvard Medical School (HMS) and a Howard Hughes Medical Institute Investigator. “Our data show that these two species have been isolated for long periods of time — making each worthy of independent conservation status.”

Interbreeding among closely related mammals is fairly common, say researchers, who point to examples of brown and polar bears, Sumatran and Bornean orangutans, and the Eurasian gold jackal and grey wolves. A species can be defined as a group of similar animals that can successfully breed and produce fertile offspring.

“This paper, the product of a grand initiative we started more than a decade ago, is far more than just the formal report of the elephant genome. It will be a reference point for understanding how diverse elephants are related to each other and it will be a model for how similar studies can be done in other species groups,” said co-senior author Kerstin Lindblad-Toh, a senior associate member of the Broad Institute and Director of the Science for Life Laboratory at Uppsala University in Sweden.

“The findings were extremely surprising to us”, says Eleftheria Palkopoulou, a post-doctoral scientist in at HMS. “The elephant population relationships could not be explained by simple splits, providing clues for understanding the evolution of these iconic species.”

Researchers suggest that future work should explore whether the introduction of new genetic lineages into elephant populations-both living and ancient-played an important role in their evolution, allowing them to adapt to new habitats and fluctuating climates.

What makes dinosaurs dinosaurs?

This 2016 video says about itself:

Dinosaurs are a diverse group of animals of the clade Dinosauria.

They first appeared during the Triassic period, 231.4 million years ago, and were the dominant terrestrial vertebrates for 135 million years, from the start of the Jurassic (about 200 million years ago) until the end of the Cretaceous (66 million years ago), when the Cretaceous–Paleogene extinction event led to the extinction of most dinosaur groups at the end of the Mesozoic Era.

The fossil record indicates that birds are modern feathered dinosaurs, having evolved from theropod ancestors during the Jurassic Period. Birds were the only dinosaurs to survive the extinction event that occurred 66 million years ago.

By Carolyn Gramling, 4:00pm, February 21, 2018:

New fossils are redefining what makes a dinosaur

Defining what’s unique about these ‘fearfully great lizards’ gets harder with new finds

“There’s a very faint dimple here,” Sterling Nesbitt says, holding up a palm-sized fossil to the light. The fossil, a pelvic bone, belonged to a creature called Teleocrater rhadinus. The slender, 2-meter-long reptile ran on all fours and lived 245 million years ago, about 10 million to 15 million years before scientists think dinosaurs first appeared.

Nesbitt, a paleontologist at Virginia Tech in Blacksburg, tilts the bone toward the overhead light, illuminating a small depression in the fossil. The dent, about the size of a thumbprint, marks the place where the leg bone fit into the pelvis. In a true dinosaur, there would be a complete hole there in the hip socket, not just a depression. The dimple is like a waving red flag: Nope, not a dinosaur.

The hole in the hip socket probably helped dinosaurs position their legs underneath their bodies, rather than splayed to the sides like a crocodile’s legs. Until recently, that hole was among a handful of telltale features paleontologists used to identify whether they had their hands on an actual dinosaur specimen.

Another no-fail sign was a particular depression at the top of the skull. Until Teleocrater mucked things up. The creature predated the dinosaurs, yet it had the dinosaur skull depression.

The once-lengthy list of “definitely a dinosaur” features had already been dwindling over the past few decades thanks to new discoveries of close dino relatives such as Teleocrater. With an April 2017 report of Teleocrater’s skull depression (SN Online: 4/17/17), yet another feature was knocked off the list.

Today, just one feature is unique to Dinosauria, the great and diverse group of animals that inhabited Earth for about 165 million years, until some combination of cataclysmic asteroid and volcanic eruptions wiped out all dinosaurs except the birds.

“I often get asked ‘what defines a dinosaur’, ” says Randall Irmis, a paleontologist at the Natural History Museum of Utah in Salt Lake City. Ten to 15 years ago, scientists would list perhaps half a dozen features, he says. “The only one to still talk about is having a complete hole in the hip socket.”

The abundance of recent discoveries of dinosauromorphs, a group that includes the dinosaur-like creatures that lived right before and alongside early dinosaurs, does more than call diagnostic features into question. It is shaking up long-standing ideas about the dinosaur family tree.

To Nesbitt, all this upheaval has placed an even more sacred cow on the chopping block: the uniqueness of the dinosaur.

“What is a dinosaur?” Nesbitt says. “It’s essentially arbitrary.”

Dinosaurs’ and birds’ locomotion

This 2016 video is called Dinosaur Walk Theory Video.

From PLOS:

Locomotion of bipedal dinosaurs might be predicted from that of ground-running birds

BIRDS Model uses just two inputs to predict terrestrial locomotion in extinct avian and non-avian dinosaurs

February 21, 2018

A new model based on ground-running birds could predict locomotion of bipedal dinosaurs based on their speed and body size, according to a study published February 21, 2018 in the open-access journal PLOS ONE by Peter Bishop from the Queensland Museum, Australia and colleagues.

Previous research has investigated the biomechanics of ground-dwelling birds to better understand the how bipedal non-avian dinosaurs moved, but it has not previously been possible to empirically predict the locomotive forces that extinct dinosaurs experienced, especially those species that were much larger than living birds. Bishop and colleagues examined locomotion in 12 species of ground-dwelling birds, ranging in body mass from 45g to 80kg, as the birds moved at various speeds along enclosed racetracks while cameras recorded their movements and forceplates measured the forces their feet exerted upon the ground.

The researchers found that many physical aspects of bird locomotion change continuously as speed increases. This supports previous evidence that unlike humans, who have distinct “walking” and “running” gaits, birds move in a continuum from “walking” to “running.” The authors additionally observed consistent differences in gait and posture between small and large birds.

The researchers used their data to construct the biomechanically informative, regression-derived statistical (BIRDS) Model, which requires just two inputs — body mass and speed — to predict basic features of bird locomotion, including stride length and force exerted per step. The model performed well when tested against known data. While more data are needed to improve the model, and it is unclear if it can be extrapolated to animals of much larger body mass, the researchers hope that it might help predict features of non-avian dinosaur locomotion using data from fossils and footprints.