Allosaurus was the most common large predatory dinosaur in western North America during the Late Jurassic Period.

The strong jaws of Allosaurus held teeth that were blade-like and serrated like a steak knife, suitable for processing meat. Much like snakes, Allosaurus had loose joints in its lower jaws that allowed it to ingest large chunks of meat.

Like most predators today, Allosaurus was probably both an active hunter and a scavenger of carcasses. Some scientists even think that it may have hunted in packs to bring down large plant-eaters such as Apatosaurus. Most claims concerning the behavior of extinct animals, however, must remain pure speculation.