Tyrannosaurus rex has long been a favorite dinosaur for many people. And since the species was named in 1905, what we know, or thought we knew, about Tyrannosaurus rex has changed a lot. From the tail dragging, pudgy monsters of old stop-motion animation to the sleek creatures of Jurassic Park, the fearsome T-rex one of the most recognizable dinosaur species out there.
A Tyrannosaurus rex fossil recently unearthed in Wyoming provides support for a long- standing but not widely known hunch about the creatures: they weren’t above eating their own kind. The fossil in question is a Tyrannosaur bone which has been broken at both ends, and has a number of grooves in it. Those grooves are what happens to a bone when a creature pulls meat off of it perpendicular to the bone itself, like when you eat a chicken wing.
That in itself just means that the animal this bone belongs to was eaten. But along the grooves on one end, whomever was gnawing on that bone scraped their teeth against it, and we can tell those teeth were serrated. Serrated teeth are common among theropods, a branch of dinosaurs that includes Tyrannosaurus rex. But the only large theropod that we know for sure lived in this area is Tyrannosaurus rex, so it looks like the T-rex may be guilty of eating other members of its species.
There is still work to be done on the fossil in question, but the evidence available so far pretty obviously points to a culprit. Further analysis will help paleontologists determine for sure if the teeth marks belong to another Tyrannosaurus, and also how big that animal was. We’ve learned from studying Komodo dragons that you can determine the size of an animal from the size of the groove left by its teeth.