A Tyrannosaurus rex is not quite as scary when you picture it with lips — but new research out of the University of Toronto suggests we ought to be doing just that. According to the new study, "beast-footed" terrestrial carnivores had lips and gums that covered their teeth, contrary to how we depict them now:

(A dentally incorrect T-Rex, courtesy iStock)

"In popular culture, we imagine dinosaurs as more ferocious-looking, but that is not the case," vertebrate paleontologist Robert Reisz said in his findings.

The support for the argument comes from looking at tooth enamel, which dries out when it isn't kept hydrated by lips. While modern day reptiles like crocodiles have the kind of exposed teeth we tend to imagine on dinosaurs, crocodiles spend most of their day in the water, which helps keep the enamel hydrated. Dinosaurs, however, were mostly terrestrial.

The study concluded that the teeth "were not exposed permanently, but covered by reptilian lips," like those on some lizards. Jeva Lange