Tyrannosaurus (Ty-ran-no-sore-us), Tyrant Lizard lived in the Late Cretaceous of North America. It was the last and among the largest predators.
1. Genera & species
3. History of Discovery
Genera and Species
Classification: Theropoda, Tetanurae, Coelurosauria, Tyrannosauroidea
Species: T. rex
Senior synonyms: T. imperiosus, T. giganteus, T. stanwinstonorum, Dynamosaurus imperiosus, Nanotyrannus lancinator, Manospondylus gigas, Stygivenator
Tyrannosaurus was one of the largest ever theropods. Its feet had 3 clawed toes pointing forwards with a smaller one at the back. Although the arms may appear tiny and puny, Tyrannosaurus were in fact quite strong and very well designed for holding struggling prey, and ended in clawed, 2-fingered hands. The jaw was 1.5 m (4.5 ft) long with 18 cm (0.6 ft), saw-like teeth.
New evidence indicates that Tyrannosaurus may have had a feathered, rather than scaled, appearance.
LENGTH: 10 - 14 m (33 - 46 ft). WEIGHT: 4.5 - 8 tons.
There has been considerable debate as to whether Tyrannosaurus was a relatively slow scavenger or a fast predator. Estimates of speed vary between 17 and 50 kph (10 - 30 mph). Other evidence in favor of the predator thesis includes its size (no large scavengers exist today), relatively large brain, large eyes with stereoscopic vision, and a keen sense of smell. It may have lived and hunted in family groups.
History of Discovery
Discovered by Osborn, in 1905 know from more than 20 skeletons in varying degrees of completeness.
Well watered plains coastal flood plains swamps and marshes. It shared the environment with Triceratops, Ankylosaurus and Edmontosaurus.
1. Paul, G. (2010). The Princeton Field Guide to Dinosaurs (pp. 2782). Princeton, New Jersey: University Press Princeton.
2. Worth, G. (1999). The Dinosaur Encyclopaedia (pp. 2334). Scarborough, Western Australia: HyperWorks Reference Software.