Big John: Famous triceratops fossil seems to have been stabbed in the head

A famous triceratops skeleton that was auctioned recently for $7.7 million has an injury to its head shield that probably came from another triceratops

By Michael Marshall

Triceratops dinosaurs probably did fight each other using their horns, according to a new study of fossilised bones with evidence of injuries sustained during life. Palaeontologists have long suspected that the horns were used for combat, but the new analysis strengthens the case.

Triceratops was among the last non-bird dinosaurs to live on Earth, just before they were all wiped out 66 million years ago. It was a four-footed plant-eater with a bony neck frill and three horns on its face: one on the snout and one over each eye.

Over the years several studies have suggested that triceratops fought using its horns, perhaps by locking them together and wrestling. This was based on triceratops fossils that showed large-scale damage, as if from impacts.

Ruggero D’Anastasio of the D’Annunzio University of Chieti-Pescara in Italy and his colleagues have examined a Triceratops horridus specimen nicknamed Big John, which was discovered in 2014 and was sold last year to a private collector.

There is a large hole in the right side of Big John’s neck frill. D’Anastasio’s team found evidence of newly formed bone around the edges of the hole, as well as signs of inflammation. This suggests Big John experienced the injury while still alive, and that the wound partially healed before the animal’s death.

What caused the injury? “The shape and size of the lesion coincides perfectly with those of a triceratops horn similar in size to Big John,” says D’Anastasio. This implies that Big John fought another triceratops, and during the battle it punctured Big John’s neck frill with its horn.

It isn’t clear whether both males and females fought, or why they fought. Males and females probably both had horns, unlike animals such as moose where only the males grow large antlers for fighting in order to compete for mates. “There are still relatively few cases to understand the behaviour of triceratops,” says D’Anastasio.

It is also unclear which other dinosaur species fought amongst themselves, due to a lack of evidence. “To the best of my knowledge,” says D’Anastasio, “there are no other cases of intraspecific fighting in other dinosaurs.”

Journal reference: Scientific Reports, DOI: 10.1038/s41598-022-08033-2

Sign up to Wild Wild Life, a free monthly newsletter celebrating the diversity and science of animals, plants and Earth’s other weird and wonderful inhabitants