Short Interesting Video of a Hermit Crab

[ProfMagoo(ret)]

So when the crab upgrades to a larger shell, it manages to move the anemones from the smaller, discarded shell over to the new, larger one. the anemones provide protection for the crab, whilst the crab's feeding indirectly feeds the anemones.

 

[DrScaryGuy]

that is a super complex set of behaviors, which suggests a much higher level of intelligence than we ever gave any of them credit for.