DINOSAURS AND OTHER REPTILES
Dinosaurs are the best known of all prehistoric creatures. However, dinosaur fossils are rare worldwide because they were land animals and, unlike sea creatures, their remains were rarely preserved. They first appeared during the Triassic Period 230 million years ago and were the dominant land animals during the Jurassic and Cretaceous periods. Dinosaurs became extinct at the end of the Cretaceous together with numerous other kinds of animals such as ammonites.
Included in this category are the great marine reptiles such as ichthyosaurs, plesiosaurs, mosasaurs and crocodiles and the flying reptiles known as pterosaurs. These creatures dominated what is now Britain during the Jurassic and Cretaceous periods, a time when much of it was covered by shallow, tropical seas. Also included in this category are the crocodiles and turtles that survived the Cretaceous extinction, and of course, birds which evolved from a group of bipedal dinosaurs.
