Why Moths Make Cocoons | Inverts For Dummies | S2 FINALE
Channel: A. B. S. E.
Date: 28/01/2023

Have you wondered why moths make their famous silken cocoons? Cocoons are actually not a part of the moth life cycle, so then why do they weave such things? 
The finale of Season 2 shall explain this...

Egg, larva, pupa, adult. The four stages of complete metamorphosis. The best example used to teach this is with butterflies and moths. Moth lifecycles are unique, in that they make special coverings known as cocoons…

Moths are the lesser-known lepidopterans. They are characterized by having feathery antennae to detect mating pheromones. 

This is how their life goes about. Caterpillars hatch from eggs, and gorge until they molt into a pupa. Now, where does the cocoon come into play? It is just before the pupal stage, when the final larval instar creates this. Cocoons are made of silk. Yes, some non-spider inverts can produce it! These include some ants, flies, caddisflies and some moths, of course. Spinnerets under the caterpillar’s head weave silk into a special latticework and this is the cocoon. 
Why do they do this? Cocoons are protective sacs which help the pupa stay undisturbed. The silk can also provide insulation, so that the adult develops properly. 
Some moths, like bagworms, incorporate other debris into their cocoon to conceal it- such as leaves and hair from their own bodies.

After a few weeks, the pupa encloses and the moth is now an adult. It then breaks out of the cocoon and, after wings harden, flies away.