For most people, the words ‘hermit crab’ likely bring to mind shy, near-motionless crustaceans sitting in a cage in the corner of someone’s bedroom. In their natural habitats, however, hermit crabs are clever, highly social creatures capable of living more than 20 years. This excerpt from the award-winning BBC One nature documentary series Life follows a group of hermit crabs on a small Caribbean island off the coast of Belize. Faced with either finding new shells or baking to death under the intense heat of the sun, the group takes part in a mutually beneficial, oceanside housing swap that truly needs to be seen to be believed.