Stegosaurus stenops

It owes its name – "roof-lizard" – to the bone plates embedded in its back, across its spinal column. The bony spikes in the Stegosaurus' tail acted as a good defensive weapon, whereas the dorsal plates were more of a deterrent. Covered with a network of blood vessels (traces of which can still be seen in the fossils), they probably had only a thin layer of skin. Whenever there was an influx of blood they would turn red and this sudden change of colour must have frightened any predators…as well as intimidating rivals, attracting females and helping to recognize its peers!
The Stegosaurus used to eat plants, such as ferns and young shoots. The front of its beak was toothless and it had only small simple teeth at the back, which it could use for cutting but not grinding vegetables. Consequently, an army of bacteria was needed in the stomach to break the food down. Some palaeontologists claim the excess heat produced had to be eliminated via the blood. The air cooled it down as it flowed through the dorsal plates.