Turtles have adapted to their environment by evolving differently shaped feet, shells and mouths. Turtles that live in the water often have flattened shells, while those living on land often have rounded shells. The feet of turtles reflect their habitat choice, as feet are generally webbed in aquatic species and elephant-like in terrestrial species. Turtles have mouths that suit their diet.
Some of the best swimming turtles, such as soft shelled turtles and Fly River turtles, have very flat shells and webbed feet. Sea turtles take aquatic adaptation even further and have limbs that are reduced to paddles. Many aquatic turtles, such as mud and musk turtles, can swim enough to survive, but they are better suited for walking along the bottom of ponds, rivers and swamps. Land-living tortoises that have to travel long distances have pillar-like feet, well adapted for carrying their heavy bodies.
Turtles that eat large prey typically have very large, powerful mouths. Snapping turtles have large, razor-edged beaks that enable them to engulf fish and other turtles. By contrast, the strange South American freshwater turtle called the mata mata hunts by sucking fish into its mouth. Accordingly its mouth has evolved to generate powerful suction forces.