Bumblebees rolling wooden balls may be first evidence of insect play

Corryn Wetzel is a writer.

The bumblebees may play for the fun. There was no reward for the insects to roll wooden balls. There may be evidence of insects playing.

Samadi Galpayage and her team at Queen Mary University of London were inspired to investigate if bees play after they found that the insects could be trained to balls into soccer goals for a food reward.

The team placed 45 bumblebees of different genders and ages in an arena with a single entrance. There was a clear aisle from the entrance to the chamber, but the insects had to go between two rooms to get there. There were balls in one room and balls in the other.

The bees were more likely to enter the zone with free- moving balls than with stationary balls. There was no incentive for the bees to roll balls between one and 118 times.

If you watched the videos of the bees on the balls, you would have no problem calling it play, according to Gordon Burghardt, who was not involved in the project.

Some bees had a better sense of humor than others. Younger bees roll more balls than older bees, and males roll more balls than females of the same age. As kittens and puppies pounce and wrestle to build hunting skills, the mental and physical exercise of play may be especially beneficial for bumblebees.

Galpayage says that ball-rolling appears voluntary and doesn't have immediate or long-term benefits for the insects. Humans can be asked if they are having fun. It's hard to assess that with animals.

The animal behavior journal has a reference.