Do bees play? A groundbreaking study says yes.

Many animals like to play, often for no other apparent reason than enjoyment. Pet owners know this is true for cats, dogs, even rodents--and scientists have observed the same in some fish, frogs, lizards, and birds. Are their minds and lives rich enough to make room for play? New research published in the journal Animal Behaviour suggests that bumblebees seem to enjoy rolling around wooden balls, without being trained or receiving rewards--presumably just because it's fun. "It shows that bees are not little robots that just respond to stimuli… and they do carry out activities that might be pleasurable," says lead author Samadi Galpayage, a researcher at the Queen Mary University of London.