Tyrannosaurus is a genus of theropod dinosaurs belonging to the Coelurosauric clad. The Tyrannosaurus rex species (often nicknamed T. rex or T-Rex; “rex” means “king” in Latin) is one of the large theropods that is best known to a wide audience. Tyrannosaurs lived on a continent known as Laramidia, which has now been transformed into western North America. Tyrannosaurus is much more spread out than other Tyrannosauridae animals. Tyrannosaurus fossils have been found in various geological formations from the Late Cretaceous around 68 to 66 million years ago. Tyrannosaurus was one of the last non-dinosaur dinosaurs before the Cretaceous-Paleogene extinction event.
Like other Tyrannosauridae animals, Tyrannosaurus is a bipedal carnivore with a large skull that is balanced by its long, heavy tail. Tyrannosaurs have large, large hind limbs, while the front limbs are short and only have two fingers. The most complete specimen of Tyrannosaurus is 12.3 m long, 3.66 m high at the pelvis (the highest point of Tyrannosaurus because it cannot stand upright), and according to most modern estimates it has a mass of between 8.4 to 14 tons.
Although other large-body theropods can rival or even exceed Tyrannosaurus rex, Tyrannosaurus is still one of the largest land predators ever found and is thought to have the strongest bite among all animals that live on land. In their environment, Tyrannosaurus rex is the largest carnivore, so they are most likely the top predators that prey on Hadrosauridae, herbivores such as Ceratopsia and Ankylosauria, and possibly also Sauropoda. Some experts believe that a pure tyrannosaurus is a scavenger. The debate about the identity of Tyrannosaurus as a top predator or carcass is one of the longest debates in paleontology. Most paleontologists today hold to the conclusion that Tyrannosaurus is a predator who also eats carcasses.
So far more than 50 specimens of Tyrannosaurus rex have been found, and some of them are almost complete. Soft tissue and protein have been found in at least one specimen. Thanks to the abundant number of fossils, researchers can investigate various biological aspects, including life history and biomechanics. Eating behavior, physiology, and the potential speed of Tyrannosaurus rex are some of the subjects that are still being debated. The taxonomy is also controversial, because some scientists consider the Tararosaurus Bataar from Asia to be the second species of Tyrannosaurus, while others consider Tarbosaurus as a separate genus. Several other Tyrannosauridae genera from North America have also been synonymous with Tyrannosaurs.