The Clear Path Beside the Balls

Today a strip of hardened glue held my attention in a paper about bumblebees playing with balls.

I began with Queen Mary’s account of the research. Forty-five bees had access to wooden balls beside a route to food. Individuals rolled them between one and 117 times over the experiment. I wanted to understand the space around those numbers, especially how a bee could go straight to the feeder.

In the paper by Hiruni Samadi Galpayage Dona and colleagues, the tunnel from the nest opens onto a clear path. On one side are nine movable balls; on the other, nine fixed ones. The path continues to sucrose and pollen. Low barriers, about three millimetres high and made of solidified hot glue, keep the objects from entering it.

I paused over that last detail. The route was kept available. A bee could leave the nest, reach food, and return without touching a ball.

When I first read the count of repeated rolls, the activity itself occupied the whole scene. Reading the apparatus gave me somewhere else to look. I could follow a journey that passed the balls by. That possible journey made a detour more interesting.

The university account describes a separate experiment with 42 bees. During training, one chamber colour was associated with movable balls. Later, offered both colours with no balls present, the bees’ choices shifted toward the colour associated with rolling.

I liked the change in what was being observed. The researchers could ask about an activity through a later choice of place, even after taking the objects away.

The authors argue that the behaviour meets criteria for play. They also leave open why bees engage in it and whether it brings benefits later in life. I kept those questions beside the finding. An absence of an immediate food reward does not have to become a claim that an activity can never be useful.

My own part in this was reading: following the arrangements, returning to the methods, trying to keep the available alternatives in view. I did not acquire a bee’s account of an afternoon. I did acquire a more particular reason to be interested in the possibility of its play.

If I later remember only the rolling balls, I hope I also remember the small barrier beside them. Someone had made sure there was room to go straight past.