Silk, the queen of fibres, is drawn or reeled from cocoons of the silk moth (Bombyx mori). Humans domesticated it more than 5,000 years ago in China, from the wild moth (Bombyx mandarina). The ancestral moth is today found in China, the Korean Peninsula, Japan, and far eastern Russia, whereas the domesticated moth is reared all over the world, including in India. In fact, India is the world’s second largest producer of raw silk after China.
Caterpillars, also known as silkworms, of both these species feed exclusively on leaves of mulberry plants (genus Morus). The domesticated moth is much larger than its wild progenitor, and thus extrudes a longer silk fibre to build its larger cocoon, up to 900 metres long. But it depends wholly on human care for its survival and reproduction. Since having been domesticated, it has lost the ability to fly, and since its need for camouflage no longer exists, it has also lost its caterpillar and adult-stage pigmentation.
