As a group, crocodilians are pretty impressive animals: Their lineage goes back 240 million years, meaning they've outlived the dinosaurs by a good 65 million years. Ideally suited for life in water and on land, members of the order can swim up to 20 mph (32 kph) and run up to 11 mph (17.6 kph). They're most at home in the water and can hold their breath for up to an hour. Eyes situated atop their heads enable them to keep a lookout for prey, while their powerful tails swiftly propel them through the water