Social Science Research Council

"That's my relative's!" [Fukushima, Japan] In a moment of discovery, a teacher finds and shows an entomologist onlooker, left, where his family's name is inscribed in a wood enframed box of cocoon samples produced by various households of Fukushima during the Meiji period. Once known as the Fukushima Sericulture School, the Fukushima Prefectural Vocational School not only has an archive and library that store unique artifacts from its silkworm teaching days, but its first principal was TOYAMA Kametaro, whose experience and research on the "improvement" of silkworms was foundational to the emergence of genetics in Japan.

Storing Silk [Tomioka, Gunma Prefecture, Japan] Silk cocoons were the hottest commodity in Japan at the beginning of the Meiji period. The government built the Tomioka Model Silk Filature, which symbolizes the jump-start of Japan's industrial production of raw silk. Machines, tended initially by daughters of the samurai class, were used to quickly draw silk thread from cocoons. Massive quantities of cocoons were necessary to compete in the export market, and cocoons were stored in enormous brick and wood structures that were longer than a football field. The mass production of machine-reeled silk necessitated the production of cocoons with uniform qualities--a holy grail for silkworm scientists and breeders.

Parenting the silkworm [Ibaraki Prefecture, Japan] With the fervor of silk export came unregulated production of new silkworm varieties. Many people had high hopes of making more silk, which meant bigger silkworms, bigger cocoons, and more thread. Based on genetic research conducted on silkworms since the turn of the twentieth century, it became possible to regulate silkworm varieties, and many of the underlying principles of heredity also made the work of breeders and human caretakers of silkworms easier. Since silkworms reproduce sexually, it is important to know how to separate females and males within a sibling group so they don't inbreed. Above, a scientist shows the result of a careful breeding program based on chromosomal research that results in unstriped male and striped female silkworms.

Sorting Silkworms [Ibaraki Prefecture, Japan] At the Institute of Sericulture, a scientist sorts through a cohort of silkworms and divides them into three groups based on larval markings and silkworm sex. Some silkworms are raised until they metamorphose inside their cocoons to emerge as moths, in order to be be mated with a different variety and lay hybrid eggs. Because of the very tightly regulated silkworm-rearing industry only accredited egg producers could sell eggs to special farmers who have the knowledge to raise silkworms until they are half-way grown. Only then are regular farmers entrusted with silkworms--about two weeks before they turn into cocoons.

Chopsticks handling silkworms [Hachioji, Tokyo] Originally a small-scale egg producer, this farmer uses chopsticks to quickly yet carefully make sure that "baby" silkworms, which are just a few millimeters when they hatch, are evenly distributed across a carpet of shredded mulberry leaves. The farmer uses a different pair of chopsticks for silkworms that lay yellow or white cocoons so that each cohort remains uncontaminated. There are about 25,000 silkworms on the bamboo-supported tray, shown above.