TyrannosaurusArticle | Updated 10 years ago Tyrannosaurus rex Image Peter Schouten Huge teeth and a bone-crushing bite enabled a fully-grown Tyrannosaurus rex to hunt and kill extremely dangerous prey. T. rex was the largest species in the tyrannosaur group and one of the last to evolve, near the end of the Cretaceous. While even larger meat-eaters belonging to other dinosaur groups have now been found, scientists think T. rex had, by far, the most powerful bite of any dinosaur. Its broad skull was made of very tough bones and had deep jaws with massive banana-shaped teeth to withstand such bone-crushing bite force. These features, as well as a strong neck and forward facing eyes, indicate T. rex was an active hunter of dangerous prey. Its highly-developed sense of smell suggests this dinosaur scavenged as well. North America (66 million years ago) Female fossils Scientists have been able to identify a T. rex fossil as female based on a feature of its living relatives. Female ostriches and emus develop a certain type of bone tissue, called medullary bone, inside their leg bones every time they produced a batch of eggs. A T. rex has been found with evidence of medullary bone tissue inside its leg bones. So the specimen can be identified as a female that died while she was producing eggs. Massive meat-eaters T. rex had a similar body size and shape to another super-predator, Carcharodontosaurus from the mid-Cretaceous, but they are not closely related. Distantly related animals that have a similar position in the food chain tend to evolve a similar body shape over time. Before carcharodontosaurs became extinct around 90 million years ago, tyrannosaurs lived as lesser predators and were relatively small. T. rex skull The skull and banana-shaped teeth of the T. rex designed for crushing the bones of its prey. IMAGE: DMITRY IDANOV Tyrannosaurus rex NAMED BY OSBORN, 1905. Diet Animals Height 4.6m Length 12.0m Width 1.8m ‹ Stomach Stones From Dinosaur to Fossil ›