![Photograph of Leatherback Sea Turtle: Scientific name: Dermochelys coriacea Common name Spanish: Tinglar Photo by Claudia Lombard, USFWS Location, Sandy Point National Wildlife Refuge, US Virgin Islands More information: [1]](/_next/image?url=https%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Ff%2Ffc%2FLeatherback_sea_turtle_Tinglar%252C_USVI_%25285839996547%2529.jpg%3Futm_source%3Den.wikipedia.org%26utm_campaign%3Dimageinfo%26utm_content%3Dthumbnail_unscaled&w=3840&q=75)
Hard-shelled turtles fuse their ribs and vertebrae into a carapace covered by keratin scutes. The leatherback abandoned that arrangement. Its back is leathery skin studded with thousands of tiny bones, drawn into seven long ridges that run from the neck to the tail.
The rebuild suits an animal that dives deep and eats gelatinous prey. Recorded dives pass a thousand metres, and the deepest confirmed descent is close to 1,280 metres. Adults commonly exceed 300 kilograms. A compressible shell, oil-rich tissue and a large body that loses heat slowly allow foraging in water far colder than other sea turtles tolerate.
The familiar description of leatherbacks as warm-blooded overstates the case. They generate heat through sustained swimming and retain it through bulk, insulation and counter-current blood flow in the flippers, but they do not hold a stable internal temperature the way a bird or a mammal does.