Even for small animals, molting can be dangerous. Wriggling out of the old exoskeleton is difficult, and once an animal makes it out, it is “squishy” and vulnerable to attack. In response to these challenges, arthropods have evolved a variety of adaptations that make molting a little less risky:
After a certain point in their life cycle, most insects simply stop growing and, hence, stop molting. For example, after they’ve developed wings, butterflies and moths don’t get any bigger, sidestepping the dangers of molting.
Molt in patches.
Pillbugs, for example, molt the back half of their exoskeleton first, and molt the front half later. This way, only half of the animal is vulnerable at a time.
Arthropods have various behavioral strategies for protection during molting. For example, molting stomatopods (lobster-like crustaceans) hide in crevices and if challenged, may try to bluff their way through a fight by behaving in a menacing and aggressive manner.