Think of a dinosaur and the first colour that comes to mind is probably grey. But some palaeontologists are now working to brighten up the dinosaur's image. Instead of drab greys, greens and browns, they imagine the prehistoric creatures in a riot of bright colours and bold markings, just like present-day mammals and birds.
No one can know for certain what colour dinosaurs were, because no skin has survived. But it is a reasonable guess, for instance, that dinosaurs that lived by hunting would have had comouflage to conceal them from their prey. Like leopards and tigers today, they may have had stripes or spots to make them harder to see in the shadows under trees.
Some dinosaurs may have made use of bright colours in their sexual behaviour. Hadrosaurs, for example, were a group of dinosaurs with strange protruberances - crests, lumps and bumps - on their heads. If these protruberances were used for sexual display, they may have shone in splendid shades of red, blue, orange or green, especially in the mating season.