Bombyx mori 300 to about 900 m (1,000 to 3,000 ft) long. The fibers are very fine and lustrous, about 10 μm (0.0004 in) in diameter. About 2,000 to 3,000 cocoons are required to make a pound of silk (0.4 kg). At least 70 million pounds of raw silk are produced each year, requiring nearly 10 billion cocoons. Due to its small size and ease of culture, the silkworm has become a model organism in the study of lepidopteran and arthropod biology. Fundamental findings on pheromones, hormones, brain structures, and physiology have been made with the silkworm. One example of this was
Bombyx mandarina 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 domesticated relative which is unable to fly or indeed persist outside human care, the wild silkmoth is a fairly ordinary lepidopteran. Its main difference from the domesticated taxon is the more slender body with well-developed wings in males, and the dull greyish-brown colour. "Bombyx mandarina" and the domesticated "Bombyx mori" constitute two of the currently identified eight species of the genus "Bombyx", the