Whereas tyrannosaurid dinosaurs like Tyrannosaurus rex had skulls that have been optimized for prime chunk forces, different gigantic carnivorous dinosaurs comparable to megalosauroids and allosauroids had a lot weaker bites and as a substitute specialised in slashing and ripping flesh, in response to an evaluation by College of Bristol paleontologists.
Tyrannosaurus rex holotype specimen on the Carnegie Museum of Pure Historical past, Pittsburgh, the US. Picture credit score: Scott Robert Anselmo / CC BY-SA 3.0.
“Carnivorous dinosaurs took very completely different paths as they advanced into giants when it comes to feeding biomechanics and potential behaviors,” stated Dr. Andrew Rowe, a paleontologist on the College of Bristol.
“Tyrannosaurs advanced skulls constructed for energy and crushing bites, whereas different lineages had comparatively weaker however extra specialised skulls, suggesting a variety of feeding methods even at large sizes.”
“In different phrases, there wasn’t one ‘greatest’ cranium design for being a predatory big; a number of designs functioned completely effectively.”
Dr. Rowe and his colleague, Dr. Emily Rayfield, wished to understand how bipedalism influenced cranium biomechanics and feeding strategies.
It was beforehand identified that regardless of reaching comparable sizes, predatory dinosaurs advanced in very completely different elements of the world at completely different occasions and had very completely different cranium shapes.
These information raised questions on whether or not their skulls have been functionally comparable beneath the floor or if there have been notable variations of their predatory life.
To look at the connection between physique measurement and cranium biomechanics, the authors used 3D applied sciences together with CT scans and floor scans analyze the cranium mechanics, quantify the feeding efficiency, and measure the chunk energy throughout 18 species of therapod, a gaggle of carnivorous dinosaurs starting from small to large.
Whereas they anticipated some variations between species, they have been stunned when their analyses confirmed clear biomechanical divergence.
“Tyrannosaurids like Tyrannosaurus rex had skulls that have been optimized for prime chunk forces at the price of increased cranium stress,” Dr. Rowe stated.
“However in another giants, like Giganotosaurus, we calculated stress patterns suggesting a comparatively lighter chunk.”
“It drove house how evolution can produce a number of options to life as a big, carnivorous biped.”
Cranium stress didn’t present a sample of enhance with measurement. Some smaller therapods skilled better stress than some bigger species resulting from elevated muscle quantity and chunk forces.
The findings present that being a predatory biped didn’t all the time equate to being a bone-crushing big.
In contrast to Tyrannosaurus rex, some dinosaurs, together with the spinosaurs and allosaurs, grew to become giants whereas sustaining weaker bites extra fitted to slashing at prey and stripping flesh.
“I have a tendency to check Allosaurus to a contemporary Komodo dragon when it comes to feeding fashion,” Dr. Rowe stated.
“Giant tyrannosaur skulls have been as a substitute optimized like trendy crocodiles with excessive chunk forces that crushed prey.”
“This biomechanical variety means that dinosaur ecosystems supported a wider vary of big carnivore ecologies than we frequently assume, with much less competitors and extra specialization.”
The research seems this week within the journal Present Biology.
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Andre J. Rowe & Emily J. Rayfield. 2025. Carnivorous dinosaur lineages undertake completely different cranium performances at gigantic measurement. Present Biology 35 (15): 3664-3673; doi: 10.1016/j.cub.2025.06.051