ABSTRACT
The outer surface of animals (Bereiter-Hahn et al, 1984) provides protection and much else for the living animal and its subsequent human user. Vertebrate-derived materials, such as leather and wool, are most commonly used, other types of animal such as molluscs and insects provide various, mostly decorative, products. The outer covering, or integument, of a vertebrate is composed of two different structures:
the dermis, which is the fibrous material forming the bulk of the skin (and leather) and consists of fibres of the protein collagen; and
the epidermis which is the protective surface of an animal, the top layer of skin, hair, balleen, horn and feathers composed of the protein keratin.
