As we saw last week in the diary Hermit Crab Basics, hermit crabs have abandoned a crustacean's typical total exoskeleton body coverage in exchange for the security of living inside an old univalve shell. The advantage of this strategy is that it can shed the portion of the exoskeleton covering the front part of its body without having to endure that dangerous "soft-shell" stage other crabs have to deal with. As I mentioned, one disadvantage is the crab must periodically find new, larger shells as it grows. As we shall see here, there are other obstacles this animals must contend with as well.