Tarbosaurus was the third biggest Tyrannosaur (up to 10m (32.8ft) in length, 3.2m (10.49ft) in height, and it weighed 4 tons) that lived in inner Asia (Mongolia and the neighbouring lands) and belonged to the tyrannosaurid branch of the theropod family: i.e., it was an Asian cousin of Tyrannosaurus. In fact, in some books it is called the asian Tyrannosaurusand for a while many scientists considered the two dinosaurs to be close relatives. However, the two carnivores have skeletal differences (especially in their skulls) that imply that they had slightly different hunting strategies, and also Tarbosaurus was a chronologically older species than the Tyrannosaurus, making it a more basic or primitive animal. It had died out as the rest of the dinosaurs, 65 MYA during the K/T mass extinction. The two larger tyrannosaurs are Zhuchengtyrannus and Tyrannosaurus, with Tyrannosaurus being slightly larger than Zhuchengtyrannus.