Butterfly & Moth Cocoons

Features

• At the most basic level, a cocoon is a casing that will keep the butterfly or moth safe while it is undergoing metamorphosis. The cocoon is made of silk or another fibrous material, and, depending on the species of the butterfly or moth, can be opaque, transparent, glossy, matte, hard or fuzzy.

Function

• The cocoon protects the insect from harsh conditions while it is undergoing its change from pupa to adult. Not only will a cocoon keep it from being eaten by a bird or another insect, it also protects against cold. Many butterflies and moths know to spin their cocoons when the temperatures start to drop. While they are in the cocoon, they do not need to eat or drink.

Process

• The material that most butterflies and moths use to spin their cocoons is silk. The silk is created in two glands that are filled with a thick, glue-like substance, and each gland will produce two threads of silk. A butterfly or moth will work in a figure-eight pattern, wrapping itself in silk. The silk is initially sticky when it emerges from the insect's body, but it becomes firm when it comes into contact with fresh air.

Misconceptions

• Contrary to popular belief, not all butterflies and moths spin cocoons. Many butterflies form a chrysalis instead, which is a hard protective shield, while some moths go into tunnels underground.

Benefits

• The silkworm moth produces cocoons that are highly valued for their silk. The cocoons are soaked in hot water and the silk is unraveled to be woven into cloth or spun into thread. The Chinese were the first to cultivate silkworm cocoons for silk, and sericulture, the cultivation of silk, began more than 4,000 years ago.