Bumblebee facial movements give clues to their inner lives

Bumblebees appear to like the taste of sugarDawn Monrose/Alamy

Bees seem to show when they are pleased and like something, rather than just needing it, in one of the strongest signs yet that insects have subjective experiences.

In recent decades, it has become clear that bees are capable of more complex behaviours than we previously thought, such as counting and demonstrating a sense of rhythm. But discerning whether they have inner states akin to our emotions is more difficult. For one thing, insects don’t have the flexible facial musculature of mammals, which we use to communicate our feelings.

“How can we get any behavioural readout of these insects with a hard body and their mask of a face,” asks Andrew Barron at Macquarie University in Sydney, Australia. “Do bees have any sort of inner state whatsoever?”

To solve the mystery, Barron and his colleagues ran a series of experiments involving buff-tailed bumblebees (Bombus terrestris).