Allosaurus

MEET THE ANIMAL

Meet Allosaurus

Allosaurus was a large meat-eating dinosaur of the Late Jurassic. Fossils of Allosaurus fragilis occur in North America's Morrison Formation, where it is a familiar predator. Its skull and teeth are valuable clues to feeding. The formation also preserves many other dinosaurs, allowing researchers to compare animals that shared this ancient setting. [D2]

An American Museum of Natural History display illustrates how fossils can inspire a life scene. Its Allosaurus cast stands beside a carcass whose bones carry grooves, possibly made by teeth or claws. Allosaurus teeth found nearby helped inspire that arrangement. The display is an interpretation of associated evidence; it does not preserve a photograph of the dinosaur feeding or show how the animal died. [S1]

Evidence inside a bone can also have competing explanations. Tissue in one specimen was interpreted as related to reproduction, but a later review argued that disease could explain it instead. That disagreement prevents the fossil from securely establishing reproductive age or nesting habits. A striking fossil may support several ideas until further evidence helps distinguish them. [D3] [D4]