Leatherback Sea Turtle (Dermochelys coriacea)
by National Geo staff
Leatherbacks are the largest turtles on Earth, growing up to 7 ft (2 m) long and exceeding 2,000 lbs (900 kg). These reptilian relics are the only remaining representatives of a family of turtles that traces its evolutionary roots back more than 100 million years. Once prevalent in every ocean except the Arctic and Antarctic, the leatherback population is rapidly declining in many parts of the world.
While all other sea turtles have hard, bony shells, the inky-blue carapace of the leatherback is somewhat flexible and almost rubbery to the touch. Ridges along the carapace help give it a more hydrodynamic structure. Leatherbacks can dive to depths of 4,200 ft (1,280 m)—deeper than any other turtle—and can stay down for up to 85 minutes.
Leatherbacks have the widest global distribution of all reptile species, and possibly of any vertebrate. They can be found in the tropic and temperate waters of the Atlantic, Pacific, and Indian Oceans, as well as the Mediterranean Sea. Adult leatherbacks also traverse as far north as Canada and Norway and as far south as New Zealand and South America.
Unlike their reptilian relatives, leatherbacks are able to maintain warm body temperatures in cold water by using a unique set of adaptations that allows them to both generate and retain body heat. These adaptations include large body size, changes in swimming activity and blood flow, and a thick layer of fat (click here)…
(read more: National Geo) (photo: Brian Skerry)