Late Jurassic (145 million years ago)
Africa, Europe, and North America
28 - 39 ft long, 16 ft tall
Allosaurus was the largest of the meat eaters in the Jurassic period. Since it lived among huge plant eaters it may have hunted in groups to take down a stegosaurus or one of the giant sauropods such as Aparosaurus or Brachiosaurus.