Bees like to roll little wooden balls as a form of play, study finds

We rarely have time to write about all the cool science stories that come our way. , conducts a special 12 Days of Christmas series of posts. Just for fun in the video, providing additional evidence that bees can experience positive “feelings”.

Many animals are known to engage in play. Usually large-brained mammals (such as humans) and birds. According to his October paper published in the journal Animal Behavior, scientists now believe they have observed genuine play behavior in bees.

“This study strongly suggests that insect minds are much more sophisticated than we imagine. bee heart“There are many animals that play just for fun, but most examples are young mammals and birds.”

According to the authors, play behaviors are usually divided into three broad categories. Social play involves playful interactions between animals. For example, there is anecdotal evidence for social play between ants and young wasps from previous studies (study dating back to 1820). Athletic play includes running, jumping, or similar strenuous sustained movements not associated with a specific purpose. Object play also includes manipulating objects as toys.

Chittka’s group conducted previous research in 2017, showing that bees can be trained to roll a small wooden ball to receive a reward. However, they also noticed instances where the bees chose to roll the ball even when there was no apparent reward or benefit. rice field. A few bees walked over the ball or stopped on their way back from food to roll it.Chitka othersI wondered if this was genuine play behavior and decided to investigate further.

Designing experiments to conclusively demonstrate that bees (or other insects or animals) specifically engage in play behaviors is not easy. It’s not okay to ask bees if they are having fun. Must meet five basic criteria.

First, no action should be taken to obtain food, attract a mate, or find shelter. It should be spontaneous, self-directed, and rewarding in itself.” Third, the motor behaviors of play behaviors should be different from those executed when foraging for food or trying to mate. To do so, play behaviors are repetitive but unconventional. Finally, play should be initiated when the subject is relaxed to distinguish it from stress-related behaviors such as pacing and walking that are common in caged zoo animals.

For these new experiments, Chitka othersI followed a similar setup. They placed his 45 bees in an arena and gave them the choice of walking along a straight line to a foraging area with food or roaming the path through an area with colored wooden balls. Even after finishing feeding, most bees (37) rolled balls for at least one extra day after feeding, and 29 balls for an additional two days. An individual bee rolled the ball from 1 to 117 times during the experiment.

In a second experiment to determine whether this was play-worthy, another 42 bees were provided access to two color-coded rooms. The ball was then removed, allowing the bees to choose which room to spend their time in. Bees had a strong preference for the colored chambers previously associated with wooden balls. In a third experiment, young bees rolled the ball more frequently than older bees, and male bees rolled the ball longer than female bees.

Overall, the authors argue that the bees’ behavior in their experiments met five basic criteria for play. “It’s certainly surprising, and sometimes funny, to see bumblebees show some sort of play,” said co-author Samadhi Galpage, a graduate student in Titka’s lab. Despite their diminutive size and small brains, they once again demonstrate that they are much more than tiny robotic beings. Even rudimentary, it is possible to experience certain positive emotional states. “

DOI: Animal Behavior, 2022. 10.1016/j.anbehav.2022.08.013 (About DOI).