Sea Turtles are large, air-breathing reptiles that inhabit tropical and subtropical seas throughout the world. Their shells consist of an upper part and a lower section. Hard scales cover all but the leatherback, and the number and arrangement of these scutes can be used to determine the species.
Sea Turtles don't have teeth, but their jaws have modified breaks suited to their particular diet. They do not have visible ears but have eardrums covered by skin. They hear best at low frequencies, and their sense of smell is excellent. Their vision underwater is good, but they are nearsighted out of water. Their streamlined bodies and large flippers make them remarkably adapted to life at sea. However sea turtles remain close ties to land.
Females must come ashore to lay their eggs in the sand; therefore all sea turtles begin their lives as tiny hatchlings on land. Research on marine turtles has uncovered many facts about these ancient creatures. Now I am going to share some information I found on two particular species of sea turtles. The fist type is the Leatherback sea turtle.
Shaped for speed and built for strength, the Leatherback turtle, Dermochelys coriacea, is a swift turtle. Attaining an average length of eight-and-a-half feet and a weight in excess of 2000 pounds, the Leatherback is by far the largest of the ocean-going turtles and indeed is the largest of all living reptiles. It is the deepest diver, reaching depths of 3000 feet. Only the elephant seal and sperm whale can swim that far down. In order to withstand the intense pressure at these depths, it is likely that the Leatherback's chest collapses, a task made possible by its lack of a rigid breastbone. Additionally, this gentle giant swims the furthest North and South, traveling as much as 3000 miles from its nesting sites and withstanding low temperatures that would stun and kill other reptilian species. It can do that because it has the ability to regulate its body temperature, a skill unique to this marine reptile.