Adult tyrannosaurs were basically two-foot bone crushing machines. New research suggests that juvenile tyrannosaurs might not match the same level of brutality, resulting in a distinctive bite that sets them apart from their adult counterparts.
There is currently nothing like tyrannosaurs and, thank God, for that. As the quintessential apex predator of the Mesozoic, these megateropods exhibited biting forces that confuse the imagination. The modern lion exerts a respectable force of 1,300 newtons of force when attacking prey, however T. rexWith his jaw wide and deep, he exerted a whopping 60,000 newtons of force with each horrible bite.
“Adult T. rex it is estimated to possess some of the highest impact bite forces recorded in any animal, with enough power to crush a car according to previous studies, “wrote Andre Rowe, a doctoral student in geology at the University of Bristol, in an email. “While the massive size and huge muscles of the animal were key to managing his amazing bite, there is also an importance in his shape, as we found that the slender jaws of the shapes younger people were less able to withstand the stresses of such a high-impact bite. “
This is the main finding of a new study led by Rowe, published on Tuesday in the scientific journal Anatomical Record. The new paper provides further evidence that juvenile tyrannosaurs were surprisingly different from the adult versions and occupied — and probably dominated — a separate ecological niche.
The aim of the new study was to explore how the feeding techniques of large predatory dinosaurs changed during their different stages of growth. Previous research showed that the minor T. rex he had a slender jaw, which eventually became the iconic deeply seen jaw he saw in adults. Rowe and colleagues “wanted to test the functional importance of this change,” he said.
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To do so, the researchers executed 3D biomechanical models based on complete tomographies T. rex skeletons, and inferences about muscle size, shape, and placement. For a youth T. rex model, researchers tested a young Mongolian tyrannosaurus named Raptorex kriegsteini.
“The main method we used in our study was an engineering technique called finite element analysis, which reveals stress and stress in solid structures,” Rowe explained. “Areas of proven structures that present a high risk of breakage will show a” hot “coloIt’s like red and white, while the colo “cold”Rs such as green and blue indicate points where the risks of breakage are minimal. “
Tests of juvenile and adult tyrannosaurs at the same jaw length showed that juveniles had higher strains, indicating the need for a wide, deep jaw shape in adults. The key to this finding was an analysis of the T. rex pterygoid muscles, located at the lower end of the jaws.
“Because we were applying virtual muscles to these dinosaurs to get accurate bite results, we had the opportunity to test the importance of individual muscles during feeding,” Rowe said. “The pterygoid muscles were found to decrease flexion forces near the front of the jaw, where T. rex he may have applied the most impactful bites through his massive, conical teeth. “
As an interesting aside, they practice modern crocodiles their highest biting forces towards the back of their jaws, while in tyrannosaurs, it is towards the front.
Rowe’s new paper suggests that the slender jaws of adolescent tyrannosaurs would have been susceptible to severe damage if the shape of the jaw remained the same throughout maturity until adulthood. But this is not the case, as he is the oldest adult T. rex the jaw is able to absorb the enormous forces needed to crush the bones. In specific terms, a youthful T. rex with a slender jaw, but with the length of an adult jaw, he would have had to endure 3.3 times the stress, which would not have worked. Hence the dramatic physical differences seen in juvenile and adult tyrannosaurs.
“Adult tyrannosaurs are known for their bone-breaking bite, which they used to swallow pieces of meat and whole bones, but the youngsters were not equipped to take a bite out of them and therefore may have used a sharp bite that they would eventually overcome, ”Rowe explained.
So instead of hunting massive herbivores like Triceratops i Edmontosaurus, juvenile T. rexes probably hunted smaller dinosaurs, and possibly even the small mammal species that existed during the Late Cretaceous, a period that ended about 66 million years ago.
“While the adult T. rex he is still an iconic apex killer, it is very remarkable to think that he started out as a slender animal that chased running mammals, ”Rowe said.
Kat Schroeder, a PhD student at the University of Mexico who was not involved in the new study, said the new research supports an idea presented in his recent paper, that juvenile tyrannosaurs were physically different enough from their parents to act as their own “morphospecies” and could have competed with other medium – sized theropods.”
Schroeder said the relatively small sample size used for the new study was “limiting,” but the science is well done,“And” fits the hypothesis that tyrannosaurs drastically changed their hunting style as they grew. “
Looking to the future, Rowe would like to see more work related to dinosaurs and other extinct animals and how feeding styles change over time.
“CT scanning and 3D modeling techniques have provided us with wonderful insights into the biology of dinosaurs, and the methods are applicable to both living and extinct animals,” he said.