Bumblebees can teach each other how to open a puzzle box

Bumblebees can teach each other how to solve a puzzle, and they prefer the method their sisters teach them to the one they learn on their own. This proves that these insects are capable of social learning, and they use it to share trends and maintain culture over time.

The researchers conducted a series of experiments in which 10 colonies of yellow-tailed bumblebees (Bombus terrestris) had to solve a puzzle box to access the sweet solution inside. There were two possible solutions – push the red lever clockwise or push the blue lever counterclockwise. Each colony had a designated demonstrator bee, who was privately taught one of two ways to open the box by a trainer. The demonstrators were then reintroduced into their colonies and the whole group had the opportunity for 3 hours every day for six to twelve days to crack the code of sweet goodness.

The bees used the trick taught by their colony mates more than 98% of the time, even when more than half of them figured out that the other lever worked just as well. “Even when they found an easy alternative, they still reverted to the demonstrated behavior,” says Alice Bridges of Queen Mary University of London. “It was really crazy.”

In colonies where humans did not teach the bees how to solve the puzzle, the bees managed to open the box only a few times.

These results indicate that behaviors can be propagated within bumblebee groups through social learning and persist over time, similar to cultural trends. “That’s exactly what we mean when we talk about cultural transmission in animal communities,” says Andrew Wythen of the University of St. Andrews in the UK, who was not involved in the work.

“These results do an exceptional job of unraveling the cultural learning of insects,” says Claudio Tenney of the University of Tübingen in Germany. But this should be seen as a “minimal” culture, he says, because it only deals with two areas of information.

The bees in these experiments transmitted information in the “know what” region – to press the lever – and in the “know where” region – which lever. But they don’t necessarily share more complex “know-how” information, such as a series of actions to be performed with a lever, Tenney says. “They land and, like sheep, they just push through,” he says. “I call these things minimal culture.”

Even a form of minimal social learning can come in handy as a buffer against global warming or other common problems. “Instead of just waiting for the less trained individuals to die through natural selection and the superior ones to survive, if you can learn a new behavior to overcome a problem, it will be really good for you,” says Bridges.