Silk Silk Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm "Bombyx mori" reared in captivity (sericulture). The shimmering appearance of silk is due to the triangular prism-like structure of the silk fibre, which allows silk cloth to refract incoming light at different angles, thus producing different colors. Silk is produced by several insects, like silk worms but generally only
Bombyx mandarina directions in a domesticated environment. Consequently, the two silkmoths have been united as subspecies of a single species; in this case the name "Bombyx mori" which was published first applies for both. However, today it is usually recognized that the domesticated silkmoth is entirely dependent on human care for its survival and thus has a level of reproductive isolation from its wild relatives. Bombyx mandarina Bombyx mandarina, the wild silkmoth, is an insect from the moth family Bombycidae. It is the closest relative of "Bombyx mori" the domesticated silkmoth or "silkworm" (properly, this refers to the caterpillars only). Unlike the