Tyrannosaurus rex tih-RAN-uh-SOR-us REX
"Tyrant lizard king"
You 1.8 m (5.9 ft) tall
Tyrannosaurus 12 m (39 ft) long
7 people holding hands
- Length
- 12 m (39 ft) — Up to 12.3 m and ~8 tonnes for the largest known individual (Scotty).
- Period
- Late Cretaceous (68–66 Mya)
- Place
- North America · Western United States · Alberta, Canada
- Food
- Carnivore — Large prey — hadrosaurs, ceratopsians, juvenile sauropods. Also a serious scavenger.
Tyrannosaurus rex was one of the last and largest meat-eating dinosaurs, living in western North America right up until the asteroid strike that ended the Cretaceous. Adults stood about 4 m tall at the hip and walked on two powerful legs, carrying a head nearly 1.5 m long lined with banana-sized serrated teeth.
For a long time T. rex was drawn in a tail-dragging, upright “Godzilla” pose. That pose is wrong. The skeleton balances horizontally over the hips, tail held off the ground as a counterweight to the head — a posture that lets a 7-tonne animal turn quickly and bite with extraordinary force.
What we know
- Over 50 known skeletons, more than any other large theropod.
- Bite force ~35,000 N — strongest of any land animal ever measured.
- Forward-facing eyes gave it strong binocular vision.
- Tiny two-fingered arms, but heavily muscled.
What we guess
- Probably had patches of feathers, especially when young. Adult body covering is debated — large body + warm climate suggests mostly scaly skin.
- How fast it ran is contested. Modern estimates: a brisk walk (~20 km/h), not a Jeep-chasing sprint.
- Whether it hunted alone or in groups — some bonebeds hint at packs, but the evidence is thin.