Tyrannosaurus Rex
Researchers find evidence of one Tyrannosaurus rex eaten by anotherWiki Commons

New archaeological findings suggest that Tyrannosaur rexes didn't just have lesser dinosaurs in their crosshairs when targeting prey, but also their own kind, as recently discovered bones point to cannibalistic tendencies. A T-Rex bone found in Wyoming was broken in half and had gnawing marks down it.

Palaeontologist Matthew McLain of Loma Linda University in California said: "Someone found a Tyrannosaur bone that was broken at both ends. It was covered in grooves. They were very deep grooves."

The research, which will be presented at the annual meeting of the Geological Society of America in Baltimore on 1 November, states that the grooves are a result of an animal pulling flesh from the bone. However, a groove located at the larger end of the bone is what has got the palaeontologists interested.

Tyrannosaur bone
Peculiar teeth marks strongly suggest the Tyrannosaur bone was gnawed by another TyrannosaurMatthew McLain

It was paralleled by smaller groves that came as the dinosaur's head turned, with the serrated edges of the teeth dragging across the bone. Serrated teeth mean that the teeth marks did not come from crocodilian creatures, but point to a therapod – like the T-Rex or its smaller cousin, the Nanotyrannus lancensis, although many palaeontologists argue that these were just juvenile T-Rexes, which were the only two therapods who roamed the Lance Formation – a division of Late Cretaceous rocks in western USA – and leaves cannibalism as the only possible cause.

"This has to be a Tyrannosaur," said McLain. "There's just nothing else that has such big teeth."

However, what the marks don't reveal is whether the diner was scavenging or was also the killer, although a statement reads: "The direction of the grooves is consistent with getting flesh from bones off an animal that was quite dead at the time."