Younger Tyrannosaurus Rex bites were less ferocious than their adult counterparts

Skeletons of four tyrannosaurid specimens tested in the study. Clockwise from above left: adult Tyrannosaurus rex 'Sue' (FMNH PR 2081) (Field Museum of Natural History, Chicago, IL; photo by the Field Museum), juvenile Tyrannosaurus rex 'Jane' (BMRP 2002.4.1) (Burpee Museum of Natural History; photo by A. Rowe), adult Tarbosaurus bataar (Dinosaurium exhibition, Prague, Czech Republic; photo by R. Holiš) and Raptorex kriegsteini skeletal reconstruction (LH PV18) (Long Hao Institute of Geology and Paleontology, Hohhot, Inner Mongolia, China; photo by P. Sereno). Listed in caption. Final image by Andre Rowe - By closely examining the jaw mechanics of juvenile and adult tyrannosaurids, some of the fiercest dinosaurs to inhabit earth, scientists led by the University of Bristol have uncovered differences in how they bit into their prey. They found that younger tyrannosaurs were incapable of delivering the bone-crunching bite that is often synonymous with the Tyrannosaurus Rex and that adult specimens were far better equipped for tearing out chunks of flesh and bone with their massive, deeply set jaws. The team also found that tension from the insertion of the lower pterygoid muscle is linked to decreasing stresses near the front of the typical tyrannosaur jaw, where the animals may have applied their highest impact bite forces using their large, conical teeth. This would be advantageous with the highly robust teeth on the anterior end of the tyrannosaur jaw, where, usually, they may have applied their highest impact bite forces.