A cocoon is a silk wrapping made from glands inside a caterpillar’s mouth. Sometimes, caterpillars will fasten leaves together, drawing them around their bodies and blending them with silk to make a cocoon. Other caterpillars, such as silk moths, forgo leaves, creating their entire cocoon from silk. Once the cocoon is created, the caterpillar pupates inside and emerges a moth.
Cocoons come in all different colors. The color is typically dependent on the environment. In order to protect themselves from predators, a caterpillar’s cocoon will blend with the plant life he’s surrounded by. For example, a luna moth’s cocoon is dark grey. The cocoon almost looks like a dried leaf. The luna moth caterpillar makes his cocoon inside tree leaves, wrapping himself in the leaf and then spinning his cocoon. By looking like a dried out leaf, the moth is protecting himself from predators.