Albertosaurus sarcophagus was a large tyrannosaur from the Late Cretaceous of western North America. This fierce, meat-eating dinosaur was shorter and lighter than Tyrannosaurus rex and belongs in a different subfamily, Albertosaurinae, along with Gorgosaurus.
Albertosaurus lived in a lush, heavily vegetated semi-tropical environment 70-74 million years ago during the Late Cretaceous Period in Canada. Most fossil remains come from a region that was once a floodplain supporting a large variety of animal life, including other dinosaurs such as hadrosaurs, ceratopsians and ornithomimids.