Small crabs in the oceans around Hawaii have developed an incredibly close relationship with sea anemones.   Known as “Boxer” or “Pom-Pom” crabs, the crustaceans carry sea anemones around in their pincers until the anemones permanently attach themselves to the crab’s claws. 

The Boxer Crab uses the anemones as a defense mechanism, waving its claws in the air wildly if a predator approaches so that the sting from the anemone will drive the other creature away. The anemones, in addition to being carried around, help themselves to leftovers of any food the crab eats.   If there are no anemones around to bond with, the crabs will improvise and use sponges and corals instead.