As humans, we might believe that we are the smartest and perhaps the only creatures in the world capable of having feelings and subjective experience, but is this really the case? A new study finds that bumblebees (大黄蜂) like to play. They like to roll around small wooden balls with no apparent motivation — it likely makes them feel good.
Previous evidence suggests that bees have positive and negative emotion-like states usually when they are given food rewards to test their abilities. However, in an experiment of the new study, some researchers had trained bumblebees to roll balls into a target in exchange for a sweet treat. They noticed that sometimes bumblebees would roll the balls outside of the experiment area for no reward.
This observation gave rise to new questions: What are they doing? Why? Is this random or intentional?
To answer these questions, the researchers set up more experiments. In the latest experiment, they watched 45 bumblebees in an enclosed area where they could walk through a clear path to reach a feeding area, or they could go off the path into areas with wooden balls. They found the bumblebees went out of their way to sit on the balls or push them. Each rolled the balls between one and 117 times during the experiment.
The researchers say that because they did it repeatedly with no food payoff, it suggests that the ball rolling was rewarding.
"The behavior was voluntary," says study first-author Samadi Galpayage. "Bees have a reputation for being hard workers, but the prospect of bees engaging in something like play is really novel and exciting because it shows that bees may experience pleasure and don't only carry out duties that are strictly essential for immediate survival."
Galpayage adds, "Personally, I find this behavior fascinating because it tells us that bumblebees, like many other animals, are more than little robotic beings, but have a richer behavior and life than we would have previously thought."
