Seven species of sea turtles call the world’s oceans home. These include the green, leatherback, olive ridley, Kemp’s ridley, hawksbill, loggerhead, and flatback. Like tortoises and freshwater turtles, sea turtles belong to the reptilian order testudines. And also like other turtles, they are perfectly adapted for the habitat in which they live - saltwater. While they do spend their lives at sea, they aren’t able to breathe underwater and they surface in order to inhale oxygen. Sea turtles have streamlined bodies and flipper-like feet for swimming through the water. The different species eat a variety of foods from seaweeds and sea grasses to crustaceans and coral; their toothless mouths have beaks adapted to their diets. They can see well as they swim in the water, and their sense of smell is thought to be well-developed.