Dilophosaurus: The Jurassic meat-eater with two crests

Dilophosaurus lived during the Early Jurassic and was one of the earliest large meat-eating dinosaurs. It is unforgettable for the two thin crests standing side by side on top of its head, like a "double-crested crown". One thing to remember: the real Dilophosaurus was a good size, about 6 to 7 metres long, and a true meat-eater.

Its body

On the top of its head stood two slender crests supported by bone. Because they were thin, they were not suited to head-butting; they more likely served for display, for recognising members of the same species, or for courtship. The colour and exact function of the crests are still being studied, so the cautious statement is: we are not yet sure.

The front of its mouth carried slightly curved fangs for grasping prey. Its shoulders and arms were strong, while its long, powerful hind legs made it a fast runner. It was a theropod that walked on two legs.

Where it lived and what it ate

Dilophosaurus was a carnivore, probably feeding on small-to-medium dinosaurs and other animals. It lived in a riverbank environment in Early Jurassic North America, where the climate was warm and vegetation was rich. As an early large predator, it played an important role in that ecosystem.

Where its fossils were found

Most Dilophosaurus fossils come from the Kayenta Formation of Arizona, United States. Researchers have carried out very complete anatomical and evolutionary analyses, so today we understand its body structure quite well.

What the fossils tell us — and what they do not

The skeleton reveals its size, the shape of the two crests and the teeth, but the colour of the crests, whether it made noise and exactly how it hunted are largely inferred. The version of Dilophosaurus that spits poison in films is pure fiction — there is no fossil evidence for it.

A note for grown-ups

You could talk with a child about "movies versus facts": many film dinosaurs are changed for entertainment and differ from the scientific evidence. Helping a child tell the difference between "a story" and "what the fossils tell us" is a good start at media literacy.