The science behind Steven Spielberg’s dino-calyptic classic Jurassic Park might have been off on any number of things, but in that memorable scene where a Tyrannosaurus rex makes mincemeat of a SUV, it got the gist right.
It turns out, also, that the hapless character who abandoned his vehicle, only to suffer the subsequent standard fate of non-starring actors, at least had the right idea: for nothing short of a tank would have probably been able to resist the chomping power of the T. Rex.
That’s because the T. Rex had a bite force of about 8,000 pounds, or 3,600 kg, while its long conical teeth could generate bone-crushing pressure of 431,000 pounds per square inch (PSI), or nearly 3 million kilopascals, according to the calculations of researchers from Florida State University and Oklahoma State University in the US.
The T. Rex combined a bite force twice that of the current world holders, crocodiles, with the bone-chewing power associated with carnivorous mammals such as wolves and hyenas, but not modern reptiles, explain Gregory Erickson and Paul Gignac in their study, published in Scientific Reports.
“Having high bite force doesn’t necessarily mean an animal can puncture hide or pulverize bone. Tooth pressure is the biomechanically more relevant parameter,” Erickson says.
The T. Rex appears to be unique among reptiles for achieving this mammal-like ability.
It was this bone-crunching acumen, known as extreme osteophagy, Gignac suggests, that enabled T. Rex to consume the carcasses of other large dinosaurs “whose bones, rich in mineral salts and marrow, were unavailable to smaller, less equipped carnivorous dinosaurs”.
Erickson and Gignac derived their conclusions from testing and modeling how the musculature of crocodilians, close relatives of dinosaurs, contribute to bite forces. They then compared the results with birds, which are modern-day descendants of the dinosaurs, and generated a model for T. rex.