From earliest times the seashore, with its rich and diverse marine fauna, has been a uniquely attractive environment for humans, providing them with accessible, palatable, and protein-rich sustenance (Sauer 1962). Among other foods – at least in warmer seas of tropical latitudes – were giant marine turtles. These could be harvested with relative ease, either on the beaches while nesting or netted or harpooned offshore. Their soft-shell and Ping-Pong-Ball-like eggs, deposited in clutches of 100 or more in the warm sand of favored beaches, provided further nutritious fare.

Among the six or seven species of giant marine reptiles that are recognized, it is the green turtle, the Chelonia mydas of turtle-soup fame, that has contributed most to the human diet. Unlike other sea turtles, the greens are exclusively herbivores, thus accounting for the savory quality of their veal-like flesh. Their name derives not from the color of their shell or skin but from the soft, greenish gelatinous material known as calipee, found beneath the plastron (lower shell) and scraped from slaughtered turtles to prepare the thick green soup renowned among gastronomes.

The flesh of other sea turtles, although eaten by some coastal peoples, is generally reputed to have a somewhat uninviting fishy taste. If the animal has ingested toxic algae or crustaceans, it may even be poisonous. The hawksbill (Eretmochelys imbricata), prized from antiquity as the source of the beautifully mottled tortoiseshell of commerce, is valued for jewelry and ornamentation, whereas the olive ridley (Lepidochelys olivacea) has recently been much sought after for its skin, used to make leather goods.