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
Mori Trust Mori Trust Mori Trust was founded in 1970 as Mori Building Development, a subsidiary of the Mori Building group founded by Taikichiro Mori. Following his death in 1993, his two sons Minoru Mori and Akira Mori disagreed as to how to continue the business, with Minoru wishing to continue the company's focus on existing properties and new large-scale urban projects, and Akira wishing to expand the company's portfolio into more small-scale office and leisure properties. This led to a split of the Mori Building group, with Akira Mori taking over the Mori Building Development entity and renaming it "Mori Trust"