The exoskeleton of crayfish is an adaptive advantage to crayfish because it gives it support and protection. A crayfish exoskeleton is the tough external material, made from chitin and calcium carbonate that envelops crayfish body. Also, the color of exoskeleton matches to the environment where the crayfish lives, this it is more difficult to find the crawfish (protection from predators and camouflages for finding the prey).
Crayfish shed their exoskeletons a few times per year in a process called molting.
