The most complete Stegosaurus skeleton in the world, this specimen was unveiled at the Natural History Museum in 2014. Although we have known about Stegosaurus for more than 130 years, not much is known about its biology. Scientists are now working on this skeleton, redescribing the species in detail and uncovering the secrets behind its evolution and behaviour. This Stegosaurus was not a fully grown animal, but at three metres tall and almost six metres long, it weighed 1,600 kilogrammes, similar to the size of a small rhino. This skeleton was discovered in Wyoming, USA, in 2003 and lived about 150 million years ago, during the Late Jurassic Period in North America. It fed on plants, including cycads and ferns, sharing the land with giant sauropods like Diplodocus, smaller herbivores and predators. We know Stegosaurus didn’t live in herds - it was probably solitary or lived in small groups. It is uncertain why the dinosaur had armoured plates. One theory is that they were used to regulate temperature by dissipating heat.