The Tyrannosaurus Rex, also known as the T-Rex, was one of the greatest predators that ever lived. And while he was certainly very big, at a length of almost 40 feet, he was not the biggest dinosaur. The Giganotosaurus, Spinosaurus & Carcharodontosaurus were bigger.




But he was one of the biggest carnivores, or meat eating dinosaurs. The T-Rex’s had a mouthful of razor sharp teeth that could be up to 12 inches long, and they could move at speeds of about 20 mph. The lived about 30 years

The T-Rex lived somewhere between 65 to 70 million years ago – in the late cretaceous period. Tyrannosaurus Rex means ‘Tyrant Lizard’. And the word dinosaur means ‘frighteningly big lizard’.

Dinosaurs were put into classifications. Some of the basic rules to decide which of these ancient creatures were dinosaurs were:

  1. They lived on land.
  2. They had straight legs tucked underneath their bodies.
  3. They were reptiles.

Of the two main types of dinosaurs, the most important difference was the shape of their hip joints. Dinosaurs with no hip bones, more like birds, are called Ornithiscia (OR-NA-THIS-KEY-A). And dinosaurs with hip bones, more like lizards, are called Saurischia (SORE-ISKIA). T-Rex was in the Saurischia classification.

What’s impressive about the T. Rex is that it had a pretty large brain for a dinosaur, which helped with its vision and smell. Some even believe it may have had telescopic vision, which would have given the T-Rex the power to zoom in its vision almost three times, giving it an almost eagle-eyed vision.

Until recently, it was thought that T. Rex lived only in North America and Asia but scientists recently discovered a hip bone belonging to an ancestor of the T-Rex in Australia. The bone came from a dinosaur that lived earlier in the Cretaceous period, about 40 million years before the T-Rex.

During this time the supercontinent began to separate and drift, becoming more like the continents we have today. So if this dinosaur made it to Australia, then it could have easily gone to the other southern continents too. This lead scientists to believe that the Tyrannosaurs may have lived all over the world – and that more bones might be discovered in South America, India and Africa. When dinosaur bones were first found hundreds of years ago by the Chinese, they thought they were the bones of giant dragons!

To this day, this deadly dinosaur’s two tiny, clawed arms (less than 3 feet in length) remain a mystery. Many scientists think they may have been used to help these skilled hunters to grab their prey.


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