What it looked like
Allosaurus was a powerful predator that walked on two strong legs, had a strong, S-shaped neck, and had vertebrae that were different from those of other dinosaurs. It had a massive tail, a bulky body, and heavy bones. It could weigh up to five tons! Its arms were short and had three-fingered hands with sharp claws that were up to 15 cm long.

Allosaurus had a skull with two short brow-horns and bony knobs and ridges above its eyes and on the top of the head. It had large, powerful jaws with long, sharp, serrated teeth 5 to 10 cm long.

Allosaurus was a very common, and lots of them were around in the late Jurassic period.

What it ate
Allosaurus was a carnivore, a meat eater equipped with sharp, pointed teeth in large, powerful jaws. This dinosaur also had long, sharp clawed hands.

Allosaurus was a large, fierce predator that could kill medium-sized sauropods (or sick or injured large sauropods like Apatosaurus) and many others. An Apatosaurus vertebra was found with Allosaurus tooth marks on it. Allosaurus may also have been a scavenger, and eaten the dead bodies of other dinosaurs that it found lying around.

How it moved around
Allosaurus walked on two legs. The length of its stride, or distance between footprints was more than two and a half metres.

Some scientists think they could not run very fast because if they fell, their short arms would not break their fall and they would be badly injured. This meant that they were slow, lumbering animals.

Other scientists have found bones with injuries, and think that sometimes an Allosaurus could have a bellyflop while running. It seems that the Allosaurus could break and crack bones falling over, but still recover.

How it probably behaved
Allosaurus may have hunted in groups. In groups, Allosaurus could ambush even the very large dinosaurs. It probably also preyed upon stegosaurs and iguanodonts. Allosaurus was the most abundant predator in late Jurassic North America. It had quite a large brain, so it was one of the most intelligent dinosaurs at that time.

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