Allosaurus was a large carnivorous dinosaur that lived around 155 to 145 million years ago during the Late Jurassic period. It measured up to 9 meters (30 feet) in length and weighed around 2.5 tons. It had a strong skull with dozens of sharp, serrated teeth, ideal for tearing flesh. Its long legs and relatively light body made it a fast and agile predator. Allosaurus also had large claws on its hands, which it likely used to grip and slash at prey. Fossils have been found mainly in North Americ

70 million years ago, a giant dinosaur would often attack its own. http://bbc.in/1LNi4Yq | BBC Earth