Allosaurus is a genus of carnivorous theropod dinosaur that lived 155 to 150 million years ago during the late Jurassic period. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles. Indeed, it has been a top feature in several films and documentaries about prehistoric life. Allosaurus was a large bipedal predator. Its skull was large and equipped with dozens of sharp, serrated teeth. It averaged 8.5 m (28 ft) in length, though fr