Giant cannibalistic dinosaurs engaged in ritualistic fighting

A species of dinosaur engaged in cannibalism, fought one another and may have even hunted members of their own species for food.

Analysis of a daspletosaurus fossil showed signs of intense and brutal combat during its life and that, following its death, its jaw was chewed on and eaten by another one of its species.

Scientists have suspected that the member of the tyrannosaurid family was a cannibal for years but analysis of the fossil, first discovered in 1994 in Dinosaur Provincial Park in Alberta, Canada, is the first to show signs of both combat and cannibalism.

Daspletosaurus were fierce predators that inhabited western North America between 77 and 74 million years ago, 10 Million years before its relative the T. Rex, but little is known about how they lived.

The fossil studied was a juvenile when it died. It would have been around six metres long and weighed around 500 kilograms. In comparison, fully grown adults would have weighed around four tonnes and could reach lengths of nine metres.

The study of the fossil was published in scientific journal PeerJ and lead author David Hone, from Queen Mary, University of London, told IBTimes UK that the rare discovery gave great insight into how the dinosaur lived:

“It’s one of those things that is entirely mundane but entirely incredible. Mundane in the sense that cannibalism is not unusual, it’s rare but it’s not unusual.

“But this case is very rare because these are big carnivores, so there’s going to be one every few dozen kilometres, and they’re not going to encounter each other on a daily basis.”

The study said that the skull, along with other daspletosaur fossils that show similar but lesser injuries to the head, suggest that the creatures took part in a form of ritualistic combat, either standing face to face or side by side.

The theories surrounding how the juvenile died range from being attacked by an alpha male, if the species was a social creature, fighting over food resources or simply picking a fight with the wrong dinosaur.

Hone said that young carnivores generally tend to be relatively naïve: “There’s no shortage of six-month-old lions trying to hunt a rhino and just getting nowhere with it until the rhino gets bored and hammers one of them, something no adult would do unless it was absolutely desperate.”

There is no evidence, despite the wounds inflicted, that the daspletosaurus was killed by another tyrannosaurid, but another member of its family certainly ate it after its death.

According to Hone, the possibility of the species going as far as to hunt each other is "not an unreasonable assertion" but, if it did take place he "wouldn't think it was common."

Research in 2010 by scientists at Yale University suggested that the Tyrannosaurus Rex could have had cannibalistic tendencies after a 65-million-year old fossil showed unusually large bite marks.

Given the age and location of the bones, also discovered in western North America, paleontologists believe that they could have only been caused by another T. Rex.