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A pair of Tyrannosaurus rex in a misty landscape

Tyrannosaurs

The family of tyrannosaurs includes the famous Tyrannosaurus rex as well as other large carnivores such as Albertosaurus and Tarbosaurus. They evolved in the late Cretaceous and their large size made them the top predators of the time. Like human beings, tyrannosaurs went through an adolescent growth spurt, increasing greatly in height and weight until they approached sexual maturity. Thereafter they grew much more slowly until they reached their final size. Tyrannosaur fossils are found in Asia and North America, through their ancestors also lived in Europe.

Scientific name: Tyrannosauridae

Rank: Family

Common names:

tyrant lizards

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Behaviours

Discover what these behaviours are and how different plants and animals use them.

Additional data source: Animal Diversity Web

When they lived

Discover the other animals and plants that lived during the following geological time periods.

Cretaceous period Cretaceous period
The Cretaceous ended with the most famous mass extinction in history - the one that killed the dinosaurs. Prior to that, it was a warm period with no ice caps at the poles.

What killed them

Cretaceous-Tertiary mass extinction Cretaceous-Tertiary mass extinction
The Cretaceous-Tertiary mass extinction - also known as the K/T extinction - is famed for the death of the dinosaurs. However, many other organisms perished at the end of the Cretaceous including the ammonites, many flowering plants and the last of the pterosaurs.

About

Eumetazoa

Tyrannosauridae (or tyrannosaurids, meaning "tyrant lizards") is a family of coelurosaurian theropod dinosaurs which comprises two subfamilies containing up to six genera, including the eponymous Tyrannosaurus. The exact number of genera is controversial, with some experts recognizing as few as three. All of these animals lived near the end of the Cretaceous Period and their fossils have been found only in North America and Asia.

Although descended from smaller ancestors, tyrannosaurids were almost always the largest predators in their respective ecosystems, putting them at the apex of the food chain. The largest species was Tyrannosaurus rex, one of the largest known land predators, which measured up to 13 metres (43 ft) in length and up to 6.8 tonnes (7.5 short tons) in weight. Tyrannosaurids were bipedal carnivores with massive skulls filled with large teeth. Despite their large size, their legs were long and proportioned for fast movement. In contrast, their arms were very small, bearing only two functional digits.

Unlike most other groups of dinosaurs, very complete remains have been discovered for most known tyrannosaurids. This has allowed a variety of research into their biology. Scientific studies have focused on their ontogeny, biomechanics and ecology, among other subjects. Soft tissue, both fossilized and intact, has been reported from one specimen of Tyrannosaurus rex.

Read more at Wikipedia

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BBC News about Tyrannosaurs

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