A 75-million-year-old tyrannosaur skull shows evidence of injuries that the dinosaur acquired during its lifetime and after its death, a new study finds. The researchers suggest that another tyrannosaur of the same genus (Daspletosaurus) may be to blame for its pre- and postmortem injuries, but other experts say it's difficult to say exactly what caused the dinosaur's wounds. [Read the story on the battered tyrannosaur skull]
An artist's interpretation of two Daspletosaurus fighting each other. A Daspletosaurus is a type of tyrannosaur, a meat-eating dinosaur that walked on two legs, had tiny hands, and sported large and sharp teeth. (Image credit: copyright: Luis Rey)
It's possible that a scavenger further damaged the Daspletosaurus' skull after the dinosaur died about 75 million years ago. The researchers found that four parallel marks on the right jaw, which is also broken closer to the face, were inflicted after the dinosaur had died.
It's possible that the four parallel marks are from widely spaced teeth belonging to another tyrannosaur, possibly of the same species, which would suggest cannibalism, the researchers said. In this image, an illustrator depicts one Daspletosaurus feeding on another.
However, other experts say more evidence is needed to pin the postmortem marks on any one dinosaur genus.
(Image credit: copyright: Tuomas Koivurinne)
The study's co-authors, Dave Hone (left) and Darren Tanke (right) sit with the Daspletosaurus skull and right jawbone (the paleontologists never found the left jawbone) at the Royal Tyrrell Museum in Alberta. (Image credit: Patty Ralrick)
The right side view of the Daspletosaurus skull. The largest of its teeth measure almost 2 inches (5 centimeters). The scale bar is 4 inches (10 cm). (Image credit: David Hone)
The right lower jaw of the daspletosaurus. Notice the bitten break point, which was possibly caused by another large tyrannosaur, the researchers said. (Image credit: David Hone)
The black arrow points to a lesion that was likely acquired during the Daspletosaurus' lifetime, the researchers said. The lesion is near the promaxillary fenestra, an opening near the front of the skull. (Image credit: David Hone | Hone and Tanke (2015) PeerJ 3:e885; DOI 10.7717/peerj.885 | Creative Commons Attribution License)