Wild Bumblebees Capable of Logical Reasoning, Study Finds

A new study by a psychologist at University of Stirling in Scotland has found that, like humans, wild bumblebees are capable of logical reasoning.

In the study, the bees were tasked with spontaneously locating strips of sugar-coated paper in various colors and positions. In both circumstances, the analysis showed they looked in the correct location well above chance, a press release from University of Stirling said.

“My studies examine the ability to make a decision by excluding alternatives, known as inferential reasoning, which is usually considered uniquely human and language dependent,” said Dr. Gema Martin-Ordas, the study’s lead researcher and a University of Stirling senior lecturer in the faculty of natural sciences, in the press release.

It was the first demonstration of insects being capable of inferential reasoning — a hallmark of human cognition.

“The ability to make a decision by excluding alternatives (i.e. inferential reasoning) is a type of logical reasoning that allows organisms to solve problems with incomplete information. Several species of vertebrates have been shown to find hidden food using inferential reasoning abilities. Yet little is known about invertebrates’ logical reasoning capabilities,” Martin-Ordas wrote in the study.

“For example, if I am presented with two cups and I am told that one of them hides a nice reward, when lifting one of them and seeing that it’s empty, I will be able to infer that it is the cup that was not lifted that hides the reward,” Martin-Ordas said in the press release. “This is the first time that this ability is shown in invertebrates, specifically in insects, and questions whether language or big brains are required for this ability. The results are very robust because bees’ performance was consistent across the experiments.”

In May 2023, 33 bumblebees were caught in Stirlingshire, United Kingdom. A transparent plastic tube was used for the two-hour experiments, after which the bees were released back into the wild unharmed.

In the United Kingdom, bumblebees are declining and two species have already become extinct. Of the remaining 24, eight species are currently prioritized for conservation because of widespread declines, the Bumblebee Conservation Trust said.

“Bee decline has become a very public symbol of [environmental] deterioration, which has galvanised conservation efforts through public appreciation,” Martin-Ordas said. “This conservation effort has been further propelled by many of the fascinating discoveries about bees’ cognition. I hope the results of my study will also contribute to these conservation efforts.”

The study, “Inferential reasoning abilities in wild-caught bumblebees,” was published in the journal Biology Letters.