4th May: Silkworms

In the French Revolutionary Calendar, today was the day of the Silkworm. Here are 10 things you probably didn't know about how silk is produced.

1. The silkworm is the larva or caterpillar of the domesticated silkmoth, Bombyx mori.
2. The moths are blind, cannot eat and cannot fly. They depend on humans to find them a mate. Once they have laid their eggs, they die.
3. A silkworm's preferred food is white mulberry leaves. It stuffs its face with them until it has grown to 10,000 times the weight it was when hatched.
4. If the moth is allowed to emerge from its cocoon, the silk is damaged - so silk production requires that the creature inside must die, usually be immersing it in boiling water; although there is research into ways of producing good quality silk while allowing the moth to survive.
5. It takes about about 2,000 to 3,000 cocoons to make a pound (0.4 kg) of silk.
6. Silkworms were first domesticated in China over 5000 years ago. It's said silk was discovered by empress Lei Zu, the wife of the Yellow Emperor and the daughter of XiLing-Shi. She was drinking Tea under a tree when a silk cocoon fell into her tea, and she noticed the cocoon unravelled to produce a fine thread.
7. The Chinese were so secretive about the method of making silk that at one time, giving the secret away, or smuggling silkworms out of the country was punishable by death. There are legends about how the secret got out to the rest of the world, including a Chinese princess given in marriage to a Khotan prince who hid silkworms in her hair and Christian monks smuggling them out in a hollow stick.
8. It's not such a big secret now, but China still leads the world in silk production, responsible for about 58,000 tons each year or about 74% of the world’s supply of raw silk.
9. The practice of breeding silkworms is called Sericulture.
10. The dead silkworms aren't always wasted - they are eaten in some parts, boiled or fried with Salt, herbs, chilli or soy sauce. In the future, they may be taken into space as food for astronauts on long term missions.