Why aren’t hermit crabs born with shells?

Hermit crabs carry their shells with them wherever they go…but they don’t make their own shells! Unlike other species of crab, hermit crabs use shells from other animals for protection. So why aren’t they born with shells of their own? We asked crab researcher Tuck Hines to help us find the answer.

Got a question that’s making you crabby? Send it to us at BrainsOn.org/contact, and we’ll share the answer un-shellfish-ly!