Secrets behind T. rex's bone crushing bites: T. rex could crush with 8,000 pound bite forces

Date: May 17, 2017

Source: Florida State University

The giant Tyrannosaurus rex pulverized bones by biting down with forces equaling the weight of three small cars while simultaneously generating world record tooth pressures, according to a new study by a Florida State University-Oklahoma State University research team.

In a study published today in Scientific Reports, Florida State University Professor of Biological Science Gregory Erickson and Paul Gignac, assistant professor of Anatomy and Vertebrate Paleontology at Oklahoma State University Center for Health Sciences, explain how T. rex could pulverize bones -- a capacity known as extreme osteophagy that is typically seen in living carnivorous mammals such as wolves and hyenas, but not reptiles whose teeth do not allow for chewing up bones.

Erickson and Gignac found that this prehistoric reptile could chow down with nearly 8,000 pounds of force, which is more than two times greater than the bite force of the largest living crocodiles -- today's bite force champions. At the same time, their long, conical teeth generated an astounding 431,000 pounds per square inch of bone-failing tooth pressures.

This allowed T. rex to drive open cracks in bone during repetitive, mammal-like biting and produce high-pressure fracture arcades, leading to a catastrophic explosion of some bones.

"It was this bone-crunching acumen that helped T. rex to more fully exploit the carcasses of large horned-dinosaurs and duck-billed hadrosaurids whose bones, rich in mineral salts and marrow, were unavailable to smaller, less equipped carnivorous dinosaurs," Gignac said.

The researchers built on their extensive experience testing and modeling how the musculature of living crocodilians, which are close relatives of dinosaurs, contribute to bite forces. They then compared the results with birds, which are modern-day dinosaurs, and generated a model for T. rex.

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