Dinosaurs / Cretaceous / Tyrannosaurus
Tyrannosaurus
Cretaceous tie-RAN-oh-SAWR-us, “tyrant lizard king”
Tyrannosaurus was one of the largest apex predators in Earth's history, roaming western North America at the climax of the Cretaceous period. Though it bore reduced, two-clawed arms, its massive hind legs supported an active hunter capable of subduing duck-billed hadrosaurs and armoured ceratopsians.
Its arms were small and two-clawed, while its hind legs were massive.
Where and when
Tyrannosaurus lived in the Late Cretaceous, from 68 to 66 million years ago (Maastrichtian age). Its remains come from United States and Canada, in the Hell Creek Formation.
The numbers
Length 12 m (estimates run from 12 to 13 m). Mass about 8.2 t. Hip height about 3.8 m. That is 7.3 human-lengths, or 1.11 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, hip height.