The Crocodile Museum Our air-conditioned museum is one of the highlights of Crocodylus Park. You can spend as long as you want here, as there's no shortage of fascinating crocodile facts. Learn about the origin of crocodiles, how many different species there are, what makes them tick, what makes them so feared - and revered. It's all here, and it's illustrated with everything from photos to live crocodiles. Take a look below for a brief glimpse at what the museum has to offer. The origin of crocodiles Crocodilians are one of the most successful groups of vertebrates on Earth - their ancestors first appeared in the fossil record over 230 million years ago, which is twice as long as the first mammals. Humans have only been around for one quarter of one million years. We often describe crocodiles as the "last of the dinosaurs", but this is not accurate. Crocodiles share a common ancestor with dinosaurs and birds (they are all archosaurs), but crocodiles are not descendants of dinosaurs. In fact, the earliest ancestors of crocodiles appeared before the dinosaurs! Did you know...? The largest crocodilians which ever lived were as long as Tyrannosaurus rex, between 35 and 40 feet (11 to 12 metres) in length, and were real dinosaur killers! Several species grew to such massive sizes, including Sarcosuchus ("king crocodile") and Deinosuchus ("terror crocodile"). Actually, Deinosuchus was probably more closely related to alligators. Crocodiles were once much more diverse than those alive today. There were terrestrial crocodiles which ran and galloped with ease, marine crocodiles which looked like dolphins, and even a fossil crocodilian with teeth suited to chewing vegetable matter. Vegetarian crocs, indeed! Believe it or not, birds are the closest living relatives of modern crocodiles. We now know that birds evolved from dinosaurs, and hence birds are literally crocodile cousins.