Butterflies DO NOT form cocoons, no matter what The Very Hungry Caterpillar says! However, not all moths form cocoons, either! Some moth species pupate underground instead. These caterpillars burrow into the soil or leaf litter, molt to form their pupa, and remain underground until the moth emerges. read more
The answer is the same for ALL juvenile arthropods including caterpillars. Their bodies grow. Their exoskeleton doesn’t grow. Hence, they have to shed their exoskeletons so they don’t get squeezed to death. read more
After the molt, while the new exoskeleton is still soft, the caterpillar swallows a lot of air, which expands its body. Then, when the exoskeleton hardens, it lets the air out and has room for growth. read more
Caterpillars molt so they can achieve a bigger size. Molting helps the caterpillar shed excess skin when they are getting bigger. Caterpillars molt so they can achieve a bigger size. Molting helps the caterpillar shed excess skin when they are getting bigger. read more
Caterpillars Molting. A caterpillar is the larval stage of a moth or butterfly. It is the only stage that has chewing mouthparts, and therefore a caterpillar spends most of its waking hours eating. This consumption of food results in massive growth, making its skin/exoskeleton very tight. read more