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
Dauer larva as "L1", "L2", "L3" and "L4". After L4, animals moult to the reproductive adult stage. However, when the environment is unfavorable, L1 and L2 animals have the option to divert their development from reproduction to dauer formation. Signals such as temperature, food supply, and levels of a dauer-inducing pheromone, a population density cue, influence this dauer decision. Dauer larvae are thus considered an alternative L3 stage larva, and this stage is sometimes preceded by L2d. L2d animals are considered pre-dauer and are characterised by delayed development and dark intestines produced by storage of fat. L2d larvae can either continue normal