Silk moth, or silk worm
The silk moth, scientifically known as Bombyx mori, is a moth species native to China that is renowned for its ability to produce silk through its larvae, commonly referred to as silk worms. This species has been domesticated for approximately 5,000 years, primarily for the valuable silk that is harvested from its cocoons. Silk moths are now predominantly bred in regions such as Asia, Australia, and parts of Europe, including Spain.
The lifecycle of the silk moth begins when the female attracts a male through pheromones. After mating, she lays several hundred eggs, which hatch into larvae that feed on mulberry leaves. These larvae grow rapidly, shedding their skins multiple times before spinning cocoons made of a single, continuous silk thread. Once they pupate within the cocoons, they eventually transform into adult moths, which are unable to fly and have lost many survival traits due to domestication.
Adult silk moths do not feed during their short lifespan of three to five days, which is solely dedicated to mating. The silk production process is sensitive; to preserve the silk, breeders typically collect the cocoons before the moths can emerge. The silk harvested is then processed and crafted into various fabrics, making silk a significant industry worldwide.
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Silk moth, or silk worm
The silk moth is a species of moth originally native to China. It is notable for its production of silk by its larvae. Because of the value of silk, this species was domesticated thousands of years ago and no longer exists in the wild. Silk moths are now primarily bred in Asia, Australia, and Spain.
Kingdom: Animalia
Phylum: Uniramia
Class: Insecta
Order: Lepidoptera
Family: Bombycidae
Genus: Bombyx
Species: Mori
The source of the smooth, soft, and expensive material people call silk is the silk moth. The first silk came from silk moths in the wild. Nearly 5,000 years ago, the Chinese began breeding silk moths and raising the young for their silken cocoons. From the thread of the cocoons, the Chinese people wove silk. Today, the manufacturing of silk is a large industry, and people all around the world wear clothing made from silk.
The silk moth is native to Asia. Japan and China are the largest breeders of silk moths. Silk moths are also bred in India, Pakistan, Turkey, France, Italy, and Russia. The moth is also raised in the Western Hemisphere, in Brazil.
The lives of silk moths begin shortly after an adult female attracts an adult male to mate with her. She attracts him with special chemicals called pheromones which the male detects with sensory hairs on his large antennae. After mating, the female then lays 300 to 500 eggs on leaves. The adults die shortly after mating. The eggs hatch into worm-like larvae. They are commonly called caterpillars or silk worms. Silk worms are born black and hairy, but they molt, or shed, their skins several times and become smooth and white. Each worm has two dark spots on the top of its back and two dark spots along the sides of each of its body's segments.
In the six weeks after they hatch, the silk worms feed constantly on mulberry leaves and grow to be three inches (7 1/2 centimeters) long. They attach themselves to the plants and spin large cases of silk, called cocoons, around their bodies. Each worm may spend about two days spinning its cocoon. The silk comes from an organ near its mouth called a spinneret. The worm produces a single, continuous thread of silk up to one mile (1 1/2 kilometers) long to make its cocoon.
The silk worms pupate inside the cocoons and transform into their adult forms. This process takes two to three weeks. The adult silk moths then emerge from their cocoons, spread their wings, and fly. Adult silk moths are one to two inches (2 1/2 to 5 centimeters) long and have wings four inches (10 centimeters) across. They have two pairs of white, hairy wings and a slender, white, hairy body with two hairy, black antennae. Adult silk moths do not feed since they have only three to five days to mate before they die.
Adult silk moths have evolved and have lost their ability to fly. They now only crawl on their six legs. They no longer have color patterns on their bodies that other species use for camouflage. Because of these adaptations, they can no longer survive in the wild.
If a silk worm is allowed to pupate into an adult moth and break free from its cocoon, the silk is ruined and may no longer be woven into material. For this reason, silk worm breeders collect most cocoons before the moths hatch. Only the largest and best cocoons are left so the moths may hatch. Breeders then breed these moths to produce more silk worms. The breeders soak the collected cocoons in very hot water. This kills the pupae inside and dissolves the glue, called sericin, holding the cocoons together. The cocoon thread is then rolled onto reels. The sericin is used to attach the ends of threads together to form longer strands of silk thread. Silk manufacturers then dye and weave this silk thread into clothing.
Similar species:
- Wild silk moth (Bombyx mandarina)
Bibliography
“Bombyx Mori.” Animalia, 2024, animalia.bio/bombyx-moriAccessed 22 Apr. 2024.
Clay, Katie. “Bombyx Mori.” Animal Diversity Web, 2001, animaldiversity.org/accounts/Bombyx‗mori. Accessed 22 Apr. 2024.
Yirka, Bob. “Genetic Study of Silkworm Helps Unravel Its Long History of Domestication.” Phys.org, 3 July 2018, phys.org/news/2018-07-genetic-silkworm-unravel-history-domestication.html. Accessed 22 Apr. 2024.