Tyrannosaurs may have been formidable predators, but even these ferocious animals may have had to watch their backs as it seems some might not have been afraid to indulge in a bit of cannibalism. A few years back, scientists discovered tooth marks on various T. rex fossils. This not only suggested that these beasts gnawed on each other, but it also hinted that cannibalism may have been common in carnivorous dinosaurs.
Now, a new crowdfunded study has gathered further evidence for this behavior in tyrannosaurs with the discovery of numerous injuries on a specimen that appears to have been inflicted by a member of the same species whilst still alive. Furthermore, adding insult to injury, the animal was also eaten after it ultimately met its demise, and the scavenger may once again have been a fellow tyrannosaur.
“This animal clearly had a tough life suffering numerous injuries across the head including some that must have been quite nasty,” lead author Dr. David Hone said in a statement. “The most likely candidate to have done this is another member of the same species, suggesting some serious fights between these animals during their lives.”
As described in PeerJ, the specimen investigated for the study was a large carnivorous tyrannosaurid called Daspletosaurus. Although a cousin of the more famous Tyrannosaurus rex, this species roamed Earth around 10 million years earlier. Like other large tyrannosaurs, it’s thought that Daspletosaurus was both a predator and a scavenger.
The mostly complete individual was discovered back in 1994 in a quarry in the lower part of the Dinosaur Park Formation in Alberta, Canada. Examination of the remains revealed that it was an adolescent when it died, measuring around 6 meters (20 feet) in length and weighing about 500 kilograms (1,100 pounds). Despite some cracking, the skull was largely well preserved and bore some interesting marks that indicated injuries sustained during life, some of which were clearly attributable to scraps with other dinosaurs.
Interestingly, some of the battle scars were a good match to the teeth of tyrannosaurs, and one particularly nasty bite even left a tooth-shaped puncture hole in the bone and broke off part of the skull. But because the bone displayed signs of healing, these injuries likely did not kill the animal, and the precise cause of death remains unknown.
Other marks along the jaw, however, indicate that the animal was also consumed after it began to decay. Furthermore, the researchers also have evidence to suggest that the rotting animal was consumed, at least in part, by another large-bodied tyrannosaur, possibly another Daspletosaurus, although they cannot be certain of the identity of the scavenger.
As mentioned, tyrannosaurs have already been accused of cannibalism, but what makes this case particularly interesting is that the animal may have sustained injuries from a fellow species member both before and after death. But since the area inhabited by Daspletosaurus was also home to other tyrannosaurs, such as Gorgosaurus, the researchers note that they cannot distinguish between scavenging by another tyrannosaurid and cannibalism.