All my life I assumed hermit crabs deal with moving house the same way us humans do. When our living space gets a bit too cramped, we find a better-suited one, vacate the old one, and move. It’s a fairly self-centered process and we rarely think about who ends up in our old space.
Well, I was wrong.
Biologists from Tufts University and the New England Aquarium recently published a paper in the journal, Behavioral Ecology, on the use of social networking by hermit crabs looking for new digs. They report that when a solitary hermit crab finds a housing upgrade, the overwhelming majority of the time, (s)he sits there by it and waits. Other ‘waiters’ soon congregate and the whole group begins to line up by size in what the authors call a ‘vacancy chain.’
If the newly discovered vacant home is too big for any of the waiting crabs, they entertain themselves by checking out the prospective homes around them. Crabs are seen grasping and piggy-backing other crab’s shells in what appears to be claim-staking for the ensuing vacancy chain. Once an appropriately sized crab finds the group and decides to upgrade into the empty shell, these piggyback lines turn into the queue and the house swapping begins.
Not only is this an efficient use of space, it also increases the likelihood of finding a well-suited shell. Plus, it doesn’t crowd up all the streets on the first of every month with moving vans and your friends are already right there to help you move your crap.
Here’s the video:
I wonder what would happen is this were the new place for rent.
Check out the full paper here.