Hermit crabs have a soft, fleshy abdomen
that can hook onto the inside of the shells
they inhabit to stay securely inside the shell.
their growing, however, they need to replace
their shells often. While they have been
observed to fight over shells, they've also
forming lines when a new possible shell is
found, so when a large hermit crab comes to
take the large shell, the smaller hermit crabs
take the next shell in line. Interestingly, when
ahermit crab dies, they release a pheromone
that indicates to others hermit crabs that a
new shell is available. - new shell is available.