Spinosaurus (meaning 'spine lizard') was arguably the largest known meat-eating dinosaur at, according to one estimate, up to 18m in length. Named for the elongated spinal bones that make up the curious sail on its back, spinosaurus was probably a fish-eater. Its head was narrow like that of a crocodile and, like that animal, might have spent its life on land and in water. It lived towards the end of the Cretaceous period, in what is now northern Africa.