Dinosaurs Facts for Kids
Roar-some facts about dinosaurs
Abelisaurid dinosaurs like Carnotaurus had arms even more reduced than T. rex's, with tiny, nearly functionless stubs. Scientists have no clear explanation for why they evolved such useless arms over tens of millions of years.
Herrerasaurus, from Argentina, is one of the oldest known predatory dinosaurs, living about 230 million years ago. It was already a capable hunter with serrated teeth, showing that carnivorous dinosaurs evolved very early on.
Oviraptorid dinosaurs often shared communal nesting sites where multiple females laid eggs in the same large nest. The male would then sit on top to incubate and guard all the eggs — a behaviour very similar to modern ostriches.
Muttaburrasaurus, an Australian dinosaur, had an enlarged, dome-shaped nasal structure that scientists think amplified its calls, making them louder and more resonant. It might have used these calls to communicate across long distances.
Fossilised skin impressions of Carnotaurus show it had a bumpy, scale-covered skin with large oval scutes scattered among smaller scales — like a crocodile. It is one of the most completely known skin patterns of any large theropod.
Patagotitan mayorum, discovered in Argentina in 2014, is the most complete giant titanosaur ever found and may be the largest land animal ever. Its femur (thigh bone) alone was 2.4 metres tall — taller than most adults.
Fossilised dinosaurs have occasionally been found in poses very similar to sleeping birds — head tucked under a wing-like arm, body curled up. This suggests non-avian dinosaurs slept in the same way their bird relatives still do today.
Hypsilophodon was a small, fast, gazelle-like dinosaur that ran on two legs to escape predators in Cretaceous Europe. For over a century scientists wrongly believed it lived in trees, but its feet were actually perfect for sprinting on the ground.
Scientists calculated that roughly 20,000 T. rexes were alive at any one time in North America, and about 2.5 billion individual T. rexes lived and died over the entire species' existence of about 2 million years.
For many years, Pachycephalosaurus was known only from its thick skull dome — the rest of its skeleton was a mystery. Because the dome was so hard and dense, it fossilised easily while the rest of the bones crumbled away.