The Leatherback

Photo by Carl Safina. Leatherback turtle in the Caribbean.
“Though the shell is turtles’ signature design feature–and all sea turtles except the Leatherback live within rigid shells–Leatherbacks have, in a sense, no shell. Their ribs do not meet or fuse but remain an open lattice-work. Rather than a hard-bone carapace shingled with scaly scutes, the back forms over a jigsaw mosaic of thousands of small, thin–only a few millimeters–bones, overlaid by a thick matrix of oily fat and fibrous tissue. The belly consists only of a fragile, narrow oval of bone that’s filled in with an expanse of heavy, fibrous tissue several centimeters (more than an inch) thick. Rather than a domed back meeting a flat belly, the whole animal is rounder, more barrel-shaped. In different languages, the Leatherback’s names refer to its shape. In the Caribbean, for instance, it’s sometimes called Trunk or Trunk-back.”
–Carl Safina, Voyage of the Turtle: In Pursuit of the Earth’s Last Dinosaur

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