Height :5 m (17ft)
Length: 40 m (12 ft)
Weight : 5.4 tonnes (6 tons)
Tyrannosaurus rex was a tyrannosaur, a carnivore that lived around 85 to 65 million years ago during the late Cretaceous period. Like the other tyrannosaurs Tyrannosaurus walked on two powerful hind legs armed with clawed, four-toed feet (the first toe was short and didn't contact the ground). Its large head was typically full of around 34 sharp serrated teeth; each tooth having another tooth growing up from under it to replace it when it came out. The head was balanced by a long stiff tail and the front arms were short to compensate for the excessive weight of the large head and torso. Powerful hind legs suggest that the tyrannosaurs could run fairly fast in pursuit of prey but some scientists argue that T-Rex would have been fatally injured if it fell at speed. A large part of Tyrannosaurus rex's brain was for processing odours, which suggests that it scavenged for food, locating rotting carcasses by smell.
The first Tyrannosaurus fossils were found by Barnum Brown in 1902. More have been found since in Canada, the western USA and in Asia. Tyrannosaurus rex was named in 1905 by Henry Fairfield Osborn. Its name means "tyrant lizard king".