As of 2009, there are 270 species of turtles, and more are being discovered. Turtles have been on the Earth for 230 million years and predate dinosaurs. Turtles have developed multiple habitats and live anywhere except the Arctic and Antarctic.
The desert tortoise lives in hot, dry environments. The Malayan box turtle lives in hot, humid and aquatic environments. The Vietnamese wood turtle lives in wooded, cool limestone mountains. The diamondback terrapin lives in brackish water throughout the eastern and southern United States.
There are seven species of sea turtles, including the green, leatherback, loggerhead, hawksbill, Kemp's ridley, olive ridley and flatback sea turtles. All turtles have shells that they cannot remove. Shells are used as protection from weather and predators. The largest turtle is the leatherback sea turtle at 95 inches long, and the smallest turtle is the speckled cape padloper tortoise measuring 3 inches. Female sea turtles lay 50 to 200 eggs in nests on the beach and return to the sea. The eggs hatch under the sand, and the hatchlings crawl toward the sea. Only about 1 in 1,000 hatchlings will survive into adulthood. Other turtles create nests in similar ways and do not attend to their nests.