Raptorex: Tiny Tyrannosaur

T. rex and Raptorex Illustration: Todd Marshall

At about 40 feet long, 20 feet tall and weighing around 7 tons, the Tyrannosaurus rex was one of the largest meat-eating dinosaurs. Now researchers have announced the discovery of the fossil remains of a small tyrannosaur in China. Raptorex was a smaller version of its descendant T. rex and had all of the same characteristics.

Raptorex had a large head compared to its torso, tiny arms, lanky feet and enlarged olfactory bulbs, which greatly enhanced its sense of smell. The researchers estimate that Raptorex was about 9 feet long and about 1/100th the size of T. rex. These findings show that the specialized features in tyrannosaurs remained constant and did not evolve as the animals grew larger.

Learn more about this discovery:

• T. Rex Body Plan Debuted in Raptorex, But 100th the Size Science Daily