Bumblebees learn to solve puzzles by watching other bees

A new study shows that bees pick up new “trends” in their behavior by watching and learning from other bees, and that one form of behavior can spread rapidly through a colony even when a different version is detected.

The research, led by Queen Mary University of London and published today (March 7) in Biology PLUSprovides strong evidence that social learning leads to widespread bumblebee behavior – in this particular case how They feed on food.

A variety of experiments have been done to prove this. The researchers designed a two-choice puzzle box that could be opened by either pushing a red tab clockwise or a blue tab counterclockwise to reveal a reward of 50% of the sucrose solution.

Bees feed from an open puzzle box by pressing the blue tab. Credit: Alice Bridges (CC-BY 4.0)

The ‘display’ bees were trained to use the red or blue tabs, with the ‘observer’ bees watching. When it was the observers’ turn to solve the puzzle, they overwhelmingly and repeatedly chose to use the same method they saw, even after discovering the alternative. This preference for the taught option was maintained by whole colonies of bees, with an average of 98.6% of box openings made using the taught method.

The importance of social learning for acquiring puzzle square solutions was also demonstrated by the control group, which lacked a demonstrator. In this group, some bees managed to open puzzle boxes, but they did so far fewer times than those who benefited from seeing another bee do so first. The average number of boxes opened per day by the control bees with a demonstrator was 28 boxes per day, while it was only one box for the control colony.

In an additional experiment, the researchers placed “blue” and “red” demonstrators into the same groups of bees. In the first population, 97.3% of the 263 cases of box opening by observers by day 12 used the red method. In the second group, the observers preferred the blue method over the red color on all but one of the days. Either way, this showed how a behavioral trend can emerge in a population in the first place—mostly, due to experienced bees retiring from foraging and the emergence of new learners, rather than any bees changing their preferred behaviour.

A bee opens a puzzle box by pressing the red tab to rotate the box lid clockwise. Credit: Bridges AD et al. 2023, PLOS Biology

Similar results from similar experiments were used in[{” attribute=””>species such as primates and birds to suggest that they, like humans, are capable of culture. If bumblebees are capable of this, too, this could potentially explain the evolutionary origin of many of the complex behaviors seen among social insects. It might be possible that what now appears instinctive could have been socially learned, at least originally.

Dr. Alice Bridges, the lead author from Queen Mary University of London, said: “Bumblebees – and, indeed, invertebrates in general – aren’t known to show culture-like phenomena in the wild. However, in our experiments, we saw the spread and maintenance of a behavioral “trend” in groups of bumblebees – similar to what has been seen in primates and birds. The behavioral repertoires of social insects like these bumblebees are some of the most intricate on the planet, yet most of this is still thought to be instinctive. Our research suggests that social learning may have had a greater influence on the evolution of this behavior than previously imagined.”

Professor Lars Chittka, Professor of Sensory and Behavioural Ecology at Queen Mary University of London and author of the book ‘The Mind of a Bee’, said: “The fact that bees can watch and learn, and then make a habit of that behavior, adds to the ever-growing body of evidence that they are far smarter creatures than a lot of people give them credit for.

“We tend to overlook the “alien civilizations” formed by bees, ants, and wasps on our planet – because they are small-bodied and their societies and architectural constructions seem governed by instinct at first glance. Our research shows, however, that new innovations can spread like social media memes through insect colonies, indicating that they can respond to wholly new environmental challenges much faster than by evolutionary changes, which would take many generations to manifest.”

Reference: “Bumblebees acquire alternative puzzle-box solutions via social learning” by Alice D. Bridges, HaDi MaBouDi, Olga Procenko, Charlotte Lockwood, Yaseen Mohammed, Amelia Kowalewska, José Eric Romero González, Joseph L. Woodgate and Lars Chittka, 7 March 2023, PLOS Biology.
DOI: 10.1371/journal.pbio.3002019