Hawksbill sea turtle are taken by humans, though it is illegal to hunt them in many countries. In some parts of the world, hawksbill sea turtles are eaten as a delicacy. As far back as the fifth century BC, sea turtles, including the hawksbill, were eaten as delicacies in China. Many cultures also use turtles' shells for decoration. These turtles have been harvested for their beautiful shell since Egyptian times, and the material known as tortoiseshell is normally from the hawksbill. In China, where it was known as "tai mei", the hawksbill is called the "tortoise-shell turtle", named primarily for its shell, which
Turtle shell the turtle shell. Embryological analyses show that the carapacial ridge initiates the formation of the turtle shell. It causes axial arrest which causes the ribs to be dorsalized, the shoulder girdle to be rearranged and encapsulated in the rib cage, and the carapace to develop. "O. semitestacea" presents evidence of axial arrest that is observed in embryos but lacks fan-shaped ribs and a carapace. This suggests that the primitive carapacial ridge functioned differently and must have gained the function of mediating the ribs and carapace development later. The plastron is the nearly flat part of the shell structure of a