After 200 years of palaeontology, dinosaurs have been studied more thoroughly than almost any other group of extinct animals. Yet new discoveries keep overturning assumptions. Here are ten facts that may surprise even committed dinosaur enthusiasts.
A 2023 study concluded that T. Rex — and likely most theropods — had lizard-like lips covering their teeth when the mouth was closed, rather than the permanently exposed teeth shown in virtually every film and artwork. Evidence comes from tooth wear patterns and comparisons with modern crocodilians versus lizards.
Computer modelling suggests that the thin, whip-like tip of Diplodocus's tail could be accelerated to supersonic speeds — generating a crack analogous to a bullwhip. This may have been used for communication, defence, or species recognition.
Richard Owen coined 'Dinosauria' — from the Greek for 'terrible lizard' — in 1842, to describe the three genera then known: Megalosaurus, Iguanodon, and Hylaeosaurus. Before that, their bones were variously identified as giants, dragons, or large unknown reptiles.
A 2018 study comparing hyoid bone (tongue support) anatomy found that T. Rex and other large theropods had tongues that were attached flat to the floor of the mouth, like a modern crocodilian — they couldn't protrude them. Another Hollywood convention overturned.
Despite being the largest land animals ever, titanosaur eggs were typically the size of a football — about 20–25 cm in diameter. A newly hatched Argentinosaurus would have weighed just 5 kg and needed to grow to 80 tonnes over its lifetime.
The northernmost dinosaur fossils come from within the Arctic Circle — places that would have experienced months of polar night. Pachyrhinosaurus and Edmontosaurus from Alaska clearly survived seasonal darkness, requiring behavioural or physiological adaptations we don't yet fully understand.
The cluster of tail spikes on Stegosaurus has an official scientific common name — thagomizer — coined in a 1982 Gary Larson Far Side cartoon, where a caveman refers to them as 'the thagomizer, named after the late Thag Simmons.' Palaeontologists found it so useful they adopted it officially.
Cryolophosaurus, a crested theropod, was found in Antarctica's Transantarctic Mountains. During the Jurassic, Antarctica was connected to other landmasses and had a warmer climate — but dinosaurs living near the South Pole still faced seasonal extremes.
Skull analysis suggests T. Rex had forward-facing eyes with overlapping visual fields — giving it stereoscopic depth perception significantly better than a modern hawk. Its visual acuity was estimated to be 13 times greater than that of a human.
Non-avian dinosaurs appeared approximately 231 million years ago and survived until 66 million years ago — a reign of 165 million years. Homo sapiens has existed for roughly 300,000 years. In geological terms, we are a very recent experiment. The dinosaurs were the most successful large land vertebrates in Earth's history.