Dilophosaurus appeared during the early Jurassic period, about 201 to 189 million years ago. It was a speedy, slender, bipedal theropod dinosaur. This means it walked on two legs and was a carnivore, a meat-eating dinosaur. It was a medium-sized predator, about 20 feet long and about five feet tall at the hip. Dilophosaurus weighed about 900 pounds as an adult. For its size, it was not a heavy dinosaur. The name Dilophosaurus means “crested lizard”. It got its name from the two paper-thin crests along the top of its snout. They were thin, bony and almost half-circles. No one knows what they were used for. Some paleontologists believe that they were used to tell males and females apart. They might have been colorful and useful to impress a mate.
Dilophosaurus had hollow bones and a curved, S-shaped neck. It had short arms with three-fingered hands. Even though ithad long, sharp teeth, its jaws were somewhat weak. They were probably not strong enough to kill its prey. But it had sharp claws on both its front and back feet. Paleontologists believe that it used its claws – rather than its jaws - to attack. It might have also been a scavenger, meaning that it ate leftovers of other dinosaurs’ food. When this dinosaur hunted for food, it usually ate smaller dinosaurs, lizards, or fish.
Dilophosaurus walked on two strong legs and was a pretty fast runner. It left small, bird-like trackmarks - or footprints - on land. Some of its fossilized tracks are only of the tips of its claws. That means that Dilophosaurus might have been walking in water at the time. Dilophosaurus may have moved about and hunted in packs or groups, since three skeletons were found together. The first fossilized skeleton was found in Arizona, North America. Skeletons have also been found in China.