 They were preyed upon by large theropods, such as "Ceratosaurus", "Megalosaurus", "Torvosaurus" and "Allosaurus", all these belong to the 'lizard hipped' or saurischian branch of the dinosaurs.During the Late Jurassic, the first avialans, like "Archaeopteryx", evolved from small coelurosaurian dinosaurs.In the air, pterosaurs were common; they ruled the skies, filling many ecological roles now taken by birds, and may have already produced some of the largest flying animals of all time.