Meet T-Rex

Tyrannosaurus Rex (tie-RAN-oh-SORE-us)

T-Rex Illustration-01.jpg

Tyrannosaurus Rex (T-Rex) has, without doubt, captured the imaginations of people all around the globe since its discovery in 1902. It is one of the most well-represented of the large theropods (a dinosaur suborder that is characterised by hollow bones and three-toed limbs) and is one of the very few dinosaurs where people can name the species!

Kingdom: Animalia

Phylum: Chordata

Clade: Dinosauria

Order: Saurischia

Suborder: Theropoda

Family: Tyrannosauridae

Genus: Tyrannosaurus

Species: Tyrannosaurus rex

Tyrannosaurus was a bipedal (walked on two legs) carnivore (meat-eater) with a massive skull balanced by a long, heavy tail. T. rex could grow to lengths of over 12.3 m. T-Rex was most likely an apex predator (top of the food chain) and would feast on many other of the dinosaurs of that time, some T-Rex fossils have been found with Tyrannosaur bite marks in them!

Their 1.5m jaw was lined with 80 serrated, banana sized pearly whites! It is estimated that T-Rex had a bite force of about 56,937 Newtons (N) making T. rex the hardest-biting terrestrial (lives on land) animal ever known! This meant he could chomp down on his prey with bone-crunching force.

Tyrannosaurus rex ruled the Earth for about 1 million years, during the Cretaceous period. Take a look at the below at the Geological Time Scale.

Scientists who study the structure and history of Earth are called geologists. Geologists study rocks and fossils or remains of living things that have been preserved in the ground. The rocks and fossils tell the story of Earth from when its crust formed 4.5 billion years ago to the present. Geologists have mapped out a time scale that is a “calendar” of Earth’s geologic history. This calendar is called the Geological Time Scale.

Can you find the Cretaceous period using the GTS below?


During this time it is likely that T-Rex was the top of the food chain, we call this an apex predator, he/she was the king of life on earth, but then disappeared in the blink of an eye.

Can you take a guess why?

You’ll notice a little dinosaur skull at the end of the Cretaceous period. This symbolises a mass extinction. That we know of there have been five mass extinction events that have seen life on earth disappear.

The mass extinction event at the end of the Cretaceous period is known as the K-T extinction global extinction event. It was responsible for eliminating approximately 80% of all species of animals.

For many years Palaeontologists have been thinking of theories as to what wiped out the Dinosaurs. When we look at rocks from the Cretaceous period we find high levels of Iridium. Iridium is not commonly found on Earth put it plentiful on Meteorites.

A massive Meteorite impact crater was discovered in the Arizonian desert in the United States confirming this theory. The Meteor that hit earth was almost 10 km across and was travelling at 128,747 kph. The impact would probably have been felt around the world. The impact could have caused a massive tsunami as well as sent molten glass beads raining down on Earth from above. The temperature around the Globe would have soared!

In the blink of an eye the dinosaurs went extinct, this terrible day for dinosaurs meant that mammals inherited the Earth.

ScienceHollie Newman