Why do silkworms spin silk?

China is a country of silk, and its silk is famous overseas. China's silk comes from silkworms. However, do you know how silkworms come from, their living habits and why they spit out beautiful and luxurious silk? Now, let me solve this mystery for you. There are many mulberry trees, trees and shrubs growing on the vast Yuan Ye in China. There are several kinds of insects living in mulberry trees. They eat mulberry leaves or tree trunks. Among these insects, one species of Lepidoptera can spin silk and form cocoons, which attracted the attention of our ancestors. This is a silkworm. Silkworms feed on mulberry leaves, spin cocoons, and then drill cocoons and feathers into moths. It has been found that this kind of cocoon shell can be soaked, and long silver thread can be drawn, twisted into thread or woven into silk. This is much better than flax and pueraria raw materials at that time. With the settlement of ancestors' life, in order to get more cocoons, people began to raise them artificially and moved indoors for domestication. It is said that the discovery of silkworms originated from an interesting legend. According to legend, there were two fathers and daughters in ancient times. Father went out to work, leaving only his daughter and a horse at home. Daughter raises horses by herself. Because of poverty and loneliness, she missed her father who worked outside the home, so she joked to Ma, "If you can take my father back, I will marry you." Hearing this, the horse broke free from the reins and went straight to his father's work. Father was very surprised when he saw the horse, so he took it away and rode it. The horse looked at the direction and groaned. When my dad saw it, he guessed that something had happened at home and rode home. Animals are very caring, so their fathers feed them more carefully. But the horse refused to eat, and every time he saw his daughter coming in and out, he would beat his hoof with anger. The father felt strange and asked his daughter quietly. Daughter has to tell the truth. Father thought it was an insult to his family, so he shot the horse with an arrow, skinned it and dried it in the yard. Father is out again. The daughter and the girlfriend next door came to Mapi and laughed at Mapi and said, "Why do you want to marry a woman as a beast?" Why recruit such a fatal disaster! "The words sound just fell and Ma Pi suddenly fly up, a daughter swept away. The girlfriend next door was too scared to save her, so she had to tell her father. When my father came back, he couldn't find it anywhere. A few days later, they were found on a big branch. My daughter and horse skin become silkworms at the same time, living in trees with thick cocoons. Neighbors take it to raise it. Because the tree is a mulberry, and because the mulberry is homophonic with mourning, it is named silkworm, which is widely raised by ordinary people and is today's silkworm. Silkworms are born as small and dark as ants. But after the silkworm baby "changed" its clothes four times, it will change from black to yellow and then to white. At this time, the silkworm's body also became fat. Then the silkworm reaches its infancy and maturity. It will start spinning and cocooning. Its cocoon is the silk we use. Maybe everyone knows that silkworms can spin silk and form cocoons. However, how silk is made may not be completely clear to everyone. Now, let me solve this problem for you. It turns out that there is a silk-making system called silk gland in silkworm larvae. Its lower part is connected to a rotating bubble called an extruder. When silkworms spin silk, the muscles on their heads will stretch back and forth to squeeze out the silk liquid in their stomachs. Silk liquid will solidify into silk when it contacts air. Just like the sweet potato we usually eat, as long as we pick it up, the sugar on the sweet potato will turn into shredded sugar when it meets the air. How's it going? Isn't that weird? Although silkworms only eat mulberry leaves all their lives, they spit out soft, smooth and white silk when they are old, so there is a poem "Spring silkworms must weave until they die" to praise those who have dedication. Although his life is short, he devoted his whole life to us.