Bumblebees can solve complex puzzles like chimpanzees and elephants, study finds

Scientist Juha-Heikki Kantola always knew bees were smart. But when he watched them solve a variation of a puzzle originally designed for chimpanzees, he was blown away.

Kantola is one of the authors of a new study in which bumblebees figured out how to manoeuvre a ball to access a sugary reward, with no previous training.

“There’s a certain kind of decisiveness about their actions,” Kantola, a physicist at Finland’s University of Oulu, told As It Happens host Nil Köksal. “It just leaves you with the feeling that there’s something going on in the brains of these creatures.”

The study’s authors say the findings, published last week in the journal Scienceprove that insects can solve problems spontaneously, a cognitive ability usually associated with large-brained vertebrates.

Variation of the ‘box-and-banana problem’

The researchers put the bumblebees through a series of experiments based on late psychologist Wolfgang Köhler’s “box-and-banana problem.”

Köhler famously demonstrated that chimpanzees could spontaneously solve problems by combining objects in new ways, including stacking boxes to snag an out-of-reach banana.

Since then, several other animals — including monkeys, elephants, pigeons and crows —  have passed variations of this test.

For the bumblebees, the researchers swapped a banana for sugar, and the boxes for a ball.

The experiments were conducted in small enclosures that are too shallow for the bees to take flight.

First, they taught the bees to associate a blue painted circle on the floor, representing a flower, with a sugary treat. Then, they moved the flower to the ceiling, just out of reach, and introduced a small ball.

The majority of bees (73 per cent) pushed the ball underneath the circle and climbed it to retrieve their sweet reward.

It’s not the first time bumblebees have solved puzzles for treats in a lab setting. But the researchers say their study stands out because the bees were “fully naïve.”

“In many previous studies of insight-like problem-solving, the animals have had extensive experience with objects, test environments or other problem-solving tasks,” behavioural ecologist Olli Loukola, one of the study’s authors, said in a press release.

“Here, the bees had never been trained to use the ball to reach the flower, and they had no previous experience with this kind of solution.”

Bumblebees solve puzzles in real life, too

But in a 2022 study, bees moved wooden balls around seemingly just for funeven when there was no reward. So how do we know these bees weren’t doing the same thing, and just happened upon the flower randomly?

To rule this out, the researchers added another layer to experiment.

The bees were allowed to explore a space with a left and right chamber, only one of which had the blue circle, before scientists introduced the ball. The researchers then used a red light to make the circle invisible, and dropped the ball in.

Most of the bees — 23 out of 30 — successfully remembered where the circle was and maneuvered the ball accordingly.

Conservation biologist Amanda Liczner, who was not involved in the research, says it makes sense that bumblebees can solve complex problems in the lab.

After all, she says, they do it in nature all the time.

When they leave the nest to forage, they must learn how to get nectar out of flowers. Each flower is different, she says, and some “can be quite tricky.”

Then they need to find their way back to the nest, often flying in larger and larger circles, likely to get a lay of the land and plot their route back.

“Bumble bees have incredible capacity for learning and memory,” Liczner, a post-doctoral researcher at Western University in London, Ont., said in an email. “You can see how these behaviours might then lend themselves to solving problems such as the one presented in the study.”

She says she hopes this research will give people a new appreciation for native bee populations, and the motivation to protect them. One way to do so, she says, is by avoiding pesticides, which can negatively impact their memory and, therefore, ability to perform the tasks necessary for survival.

“The more you learn about them the more you realize how incredible they are,” she said.

Kantola says it’s hard to define things like consciousness or intelligence. But he says the study shows that some of the cognitive abilities people think of as “special to mankind” aren’t so special after all.

“That’s somehow, you know, heartwarming for me in this day and age,” he said.