a.shed their skin..
Step-by-step explanation:
Exoskeleton
A true exoskeleton, like that found in arthropods, must be shed (moulted) when it is outgrown. ... The new exoskeleton is still capable of growing to some degree, however. Animals of the order arthropoda, like lizards, amphibians, and many other animals that shed their skin, are indeterminate growers