Most modern species of turtles are semi-aquatic, living in such habitats as ponds, swamps, and marshes. Several species are marine. In fact, turtles have diversified into species that are specialized in various ways. The sea turtles, for example, are ocean-dwelling animals that fly through the water using their paddle-like forelimbs, emerging on land only to lay their eggs. Others turtles, such as the soft shells, are river- and lake-dwellers, and are flattened like a pancake to hide on sandy or muddy bottom habitat. Still others, such as the tortoises, are strictly land-dwellers, with a high domed shell, elephant-like feet, and ranging into grasslands and semi-desert habitats.
Many turtles are omnivores, eating both plants and animals, but others are more specialized in their food habits. The giant tortoises and some of the sea turtles are vegetarian as adults, although their young may eat invertebrates or small vertebrates. Some river turtles, such as the map turtles (Graptemys spp.), are specialists that feed only on snails and clams. Softshell turtles (Trionyx spp.) are mainly fish-eaters, while snapping turtles (Chelydra serpentina) will eat any animal they can subdue.
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