T. rex used a stiff skull to eat its prey
(PHYSorg.com Archaeology & Fossils)

A Tyrannosaurus rex could bite hard enough to shatter the bones of its prey. But how it accomplished this feat without breaking its own skull bones has baffled paleontologists. That`s why scientists at the University of Missouri are arguing that the T. rex`s skull was stiff much like the skulls of hyenas and crocodiles, and not flexible like snakes and birds as paleontologists previously thought.