T-Rex myths busted: What did Jurassic Park get wrong?

Tyrannosaurus rex was a species of Theropoda dinosaur in the Late Cretaceous period. Like other tyrannosaurids – such as Tarbosaurus and Gorgosaurus – the T-rex was a bipedal carnivore and apex predator and scavenger, preying on smaller dinosaurs directly or out-muscling them for their kills. Typical prey included hadrosaurs and ceratopsians.

Tyrannosaurus rex’s name translates as ‘tyrant lizard king’ – something that was historically attributed due to its immense size. Indeed, the Tyrannosaurus rex is one of the largest species ever excavated by palaeontologists, with specimens averaging over 12 metres (40 feet) in length and four metres (13 feet) in height, but it wasn’t the biggest carnivorous dino. It was also incredibly heavy with fully grown adults weighing up to nine tons; this figure was suggested in 2011 after an in-depth study which made digital 3D models of five T-rex skeletons.

Due to their considerable size, the Tyrannosaurus rex had very few, if any, predators – a fact that enabled it to remain unchallenged as the Late Cretaceous era’s apex predator on land and to live for lengthy periods. Estimates taken from excavated specimens – of which there are now more than 30 confirmed around the world – indicate that the T-rex’s life span was roughly 30 years, with the majority of growth taking place in the first 16 years before tailing off rapidly. This suggests that the Tyrannosaurus rex would have reached adulthood at approximately 20 years of age.

As with almost all species of Dinosauria, the Tyrannosaurus was wiped out over 66 million years ago in the Cretaceous-Palaeogene (K-Pg) extinction event. At the time it was one of the last widespread non-avian dinosaurs, as evidenced by the discovery of many specimens throughout North America.

Movie myths about the T-Rex

  • Despite being a prominent star of all the Jurassic Park films, Tyrannosaurus rex did not exist in the Jurassic period (199-145 MYA). In fact, it lived millions of years later during the Late Cretaceous (100-65.5 MYA).
  • T-rex has been depicted as having green scaly skin. However, recent evidence suggests its skin colour was varied and, during the early years of its life, it probably sported insulative feathers.
  • The T-rex has also been commonly lauded as the biggest carnivorous dinosaur of them all. This isn’t strictly true, with palaeontological evidence suggesting the species Spinosaurus outsized it by over three metres (9.9 feet) in length.
  • Another myth perpetuated in Jurassic Park is that the Tyrannosaurus could run at high speed (ie keep up with a car), but it could probably only manage about 40 kilometres (25 miles) per hour due to its relatively small strides.

Top 5 T-Rex Facts

1) Scavenger

Excavated evidence suggests that, as well as being an active predator, the Tyrannosaurus was also an opportunistic scavenger, commandeering kills from smaller carnivores.

2) Cannibal

A study put forward in 2010 posits that Tyrannosaurus was cannibalistic. The theory was determined when researchers found specimens with same-genus tooth marks.

3) Bad posture

Tyrannosaurus rex was historically depicted with its body at 45 degrees or less from the vertical. This is not accurate, with a more horizontal posture likely.

4) Big foot

Two excavated fossilised footprints have been attributed to T-rex. The latest measures 83 centimetres (33 inches) in length and 71 centimetres (28 inches) wide.

5) Feathery young

According to a report in the journal Nature, Tyrannosaurus young may have been feathered for insulation, only losing their plumage in later years.

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Plus, take a look at:

How did the T-Rex hunt its prey?

Interview with T-Rex Autopsy palaeobiologist Dr Tori Herridge

Top 5 Facts about dinosaurs