Artistic rendition of Ptychotherates bucculentus.
Illustration by Megan Sodano for Virginia Tech.
The fossil is of an ancestral dinosaur from the Late Triassic, about three times older than Tyrannosaurus rex, dating from an era when dinosaurs had not yet risen to dominance and were still competing with the ancestors of crocodiles and mammals. It was the mass extinction at the end of the Triassic that cleared the way for the dinosaurs, just as their own extinction at the end of the Cretaceous later cleared the way for mammals and birds.
For creationists, the fact that all this unfolded over a vast span of time long before the supposed creation of the small, flat world of Biblical mythology is simply one more test of how much evidence they are prepared to ignore. Unlike science, which stands or falls by the evidence, creationism seems to draw strength from defying it. The greater the weight of evidence against it, the more loudly its followers proclaim their faith to be unshaken. So while creationists on social media endlessly demand that science prove its case to an impossible standard, and try to pass misinformation or ignorance off as “proof” of creationism, they routinely dismiss real evidence and treat stubborn refusal to change their minds as a kind of victory. In creationist circles, winning a debate too often seems to mean not changing one’s mind, even when the facts leave no honest alternative.
This latest inconvenience for creationism comes from Virginia Tech, where student Simba Srivastava succeeded in reconstructing fragments of a dinosaur skull embedded in rock from New Mexico’s Ghost Ranch. The fossil had originally been unearthed in 1982, but was later rediscovered in a drawer at the Carnegie Museum of Natural History by palaeontologist Sterling Nesbitt. Back at Virginia Tech, Srivastava used computed tomography scan data to create a 3D print of the skull, revealing that it belonged to a previously unknown species of early dinosaur.
Background^ the end-Triassic mass extinction. The end-Triassic mass extinction took place about 201.36 million years ago, at the boundary between the Triassic and Jurassic periods. It is generally counted as one of the “Big Five” mass extinctions in the history of complex life and marks one of the great turning points in Earth’s biological history. [1]The discovery and its significance are explained in a news item from Virginia Tech by Kelly Izlar:
The leading explanation is not an asteroid impact, but massive volcanism associated with the **Central Atlantic Magmatic Province** (CAMP), which erupted as the supercontinent Pangaea began to break apart. These eruptions released huge quantities of carbon dioxide and other gases, disrupting the carbon cycle, driving rapid global warming, and triggering severe environmental stress on land and in the oceans. Recent research has also added direct evidence for significant ocean acidification during this crisis. [2]
Marine ecosystems were hit especially hard. Many ammonoids declined sharply, conodonts disappeared altogether, reef systems suffered badly, and large numbers of marine invertebrates were lost. On land, the extinction reshaped ecosystems by removing many of the reptile groups that had been competing with early dinosaurs, especially among the crocodile-line archosaurs. That ecological upheaval helped set the stage for dinosaurs to become dominant in the Jurassic. [3]
Strictly speaking, the end-Triassic extinction did not kill the individual animal from Ghost Ranch, because that fossil predates the event. What it may have done, however, is wipe out its lineage. The new Virginia Tech discovery is important because it suggests that the extinction did not simply eliminate the dinosaurs’ competitors; it may also have finished off some of the oldest dinosaur branches themselves. [4]
Student identifies new meat-eating dinosaur three times older than T. rex
A fossil skull provides new clues about how dinosaurs ascended to their full Jurassic power.
You want to stick your finger in a dinosaur brain?
Simba Srivastava, co-first author. Department of Geosciences
Virginia Tech
Blacksburg, Virginia, USA.
Surrounded by cabinets full of ancient bones in the paleobiology lab, the Virginia Tech undergraduate student held out a lumpy, pockmarked fossil.
This is a uniquely sucky specimen. It's so bad. Like, if you saw a human skull in this way, you'd throw up.
Simba Srivastava.
Nevertheless, the senior geosciences major spent two years unscrambling the ancient creature and determining its place in the story of evolution. His findings, which were published April 15 in Papers in Palaeontology, shed light on how dinosaurs dominated the Jurassic period.
This is the type of work a long-tenured curator or a late-stage professor would do, but geobiologists Sterling Nesbitt and Michelle Stocker tapped Srivastava when he was a first-year student.
We want undergraduate researchers to experience the whole paleontological research process at Virginia Tech. Simba grabbed the project by the reins.
Sterling Nesbitt, co-first author.
Department of Geosciences
Virginia Tech
Blacksburg, Virginia, USA.
Dino domination
Artistic rendition of Ptychotherates bucculentus.Illustration by Megan Sodano for Virginia Tech.
The mangled skull was uncovered twice: In 1982, a crew from the Carnegie Museum of Natural History unearthed it from New Mexico’s Ghost Ranch. Thirty-some years later, Nesbitt dug it out of a drawer and eventually brought it back to Blacksburg. Using computed tomography scanning data, Srivastava isolated the specimen digitally and 3D printed a reconstruction.
The skull belonged to a species of meat-eating dinosaur that’s more than three times as old as Tyrannosaurus Rex.
These creatures lived at the end of the Triassic period, which is about 252 million to 201 million years ago. Back then, dinosaurs weren’t the all-powerful apex predators portrayed by Hollywood. They were vying for resources against the forerunners of crocodiles and mammals.
But that all changed drastically when an extinction seemingly wiped out most of the competition. With that, the Triassic ended, and dinosaurs came into their power.
Dinosaurs go from being co-stars to the headliner.
Simba Srivastava.
Clues about how dinosaurs evolved and spread in the succeeding Jurassic period lie buried in the rocks, but well-preserved fossils from the end of the Triassic are rare.
In fact, Srivastava’s squished specimen is the only one of its kind anyone has found so far.
The skull shows that the species had massive cheekbones, a wide braincase, and probably a short, deep snout. It was the first time these characteristics had been seen in early dinosaurs, indicating that they were constantly evolving, according to the study.
Murder muppet’s last stand
The name Srivastava picked for the new species reflects its bizarre proportions and unfortunate condition.
We landed on Ptychotherates bucculentus, which means ‘folded hunter with full cheeks’ in Latin. One paleo-artist said that it looked like a murder muppet.
Simba Srivastava.
After two years of deep research, the Virginia Tech team was able to determine that the skull belonged to one of the last surviving members of one of the earliest-evolving families of carnivorous dinosaurs called Herrerasauria.
Thanks to this fossil, the group made another, somewhat surprising discovery.
Ptychotherates was found in rocks that may date to right before the great extinction at the end of the Triassic period — and no other members of their family was ever seen again, possibly suggesting that this dinosaur group went extinct as a result of that mass extinction.
This forces us to reconsider the impact of the end-Triassic extinction as something that wiped out not just the competitors to dinosaurs, but some long-standing dinosaur lineages themselves.
Simba Srivastava.
12(2 And finally, because no herrerasaurians have been found anywhere else this late in the Triassic, the area that is today the American Southwest may have been where they survived the longest and made their last stand.
Srivastava’s folded hunter is their only spokesperson.
This specimen, it fits in my hands, but it is the only proof that any of these dinosaurs lived this long, lived in these latitudes, the only proof that they evolved to have this skull shape. All these billions of individuals that existed through time are spoken for by this one specimen.
Simba Srivastava.
Publication:
What this fossil shows, yet again, is that the history of life is not a neat sequence of separately created “kinds”, but a branching, contingent, and often untidy evolutionary story unfolding over immense spans of time. *Ptychotherates bucculentus* comes from a world long before the age of *Tyrannosaurus rex*, from a phase in dinosaur evolution when their future dominance was by no means guaranteed. It lived in an ecosystem in which early dinosaurs were still only one part of a wider community, and its discovery helps illuminate a stage in their history that was previously obscure.
It also underlines the importance of deep time in explaining the living world. The end-Triassic mass extinction was not some minor local event but a global ecological upheaval that reshaped life on Earth, removing entire lineages and opening ecological opportunities for others. Without that extinction, the subsequent rise of the dinosaurs might have looked very different; without the later end-Cretaceous extinction, mammals and birds would not have inherited the world in the way they did. Evolution works not to a preconceived plan but through descent with modification, constrained by history and repeatedly redirected by changing environments and extinction events.
That, of course, is precisely what makes discoveries like this so awkward for creationism. The fossil record does not reveal a sudden appearance of fixed, separately created forms in a young world. It reveals succession, transition, diversification, extinction, and replacement across millions of years. Each new fossil from the Triassic adds another detail to that picture, and every such detail fits the scientific account of life’s history far better than it fits the simplistic mythology of special creation.
So, another fossil, another fragment of the deep past recovered from stone, and another reminder that reality is under no obligation to conform to Bronze Age stories. Science advances by following the evidence wherever it leads, even when that means revising earlier ideas. Creationism, by contrast, survives only by ignoring that evidence. Fossils such as Ptychotherates bucculentus are valuable not merely because they fill gaps in our knowledge, but because they show, once again, that the real history of life on Earth is vastly older, richer, and more complex than creationist dogma can ever allow.
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