Tortoiseshell Tortoiseshell Tortoiseshell or tortoise shell is a material produced from the shells of the larger species of tortoise and turtle, mainly the hawksbill sea turtle, which is an endangered species largely because of its exploitation for the material. The large size, fine colour and unusual form of the hawksbill's scutes make it especially suitable. The distinctive patterning is referred to in names such as the tortoiseshell cat, several breeds of guinea pig, and the common names of several species of the butterfly genera "Nymphalis" and "Aglais", and some other uses. Tortoiseshell was widely used from ancient times in the West
Turtle shell the study of the evolution of the turtle's shell. The first piece of fossil record discovered, essential for building the evolution and development model, was Germany and Thailand’s 214-million-year-old Late Triassic reptile "Proganochelys", which marked as the first point of full shell development and carapace ossification in Testudines. The following phenomenal discovery of China’s 220-million-year-old stem turtle, predating the "Proganonchelys" by 6 million years, the "Odontochelys semitestacea" fossil in China shed light on the intermediate stages of turtle carapace evolution by exhibiting a partially formed dorsal carapace. One major discovery was that "O. semitestacea" provided documentation that the plastron evolved