Scientists now know that bees can process time, a first in insects

Bumblebees can process the duration of flashes of light and use the information to decide where to look for food, a new study has found.

This is the first evidence of such an ability in insects, according to doctoral student Alex Davidson and his supervisor Elisabetta Versace, a senior lecturer in psychology at Queen Mary University of London. The discovery could help settle a long-standing debate among scientists about whether insects are able to process complex patterns, Versace told CNN.

“In the past, it was thought that they were just very basic reflex machines that don’t have any flexibility,” she said.

To reach its finding, the team set up a maze through which individual bees would travel when they left their nest to forage for food.

Researchers presented the insects with two visual cues: one circle that would light up with a short flash and another with a long flash of light.

Approaching these respective circles, the bees would find a sweet food that they like at one, and a bitter food, which they don’t, at the other.

The circles were in different positions at each room in the maze, but the bees still learned over varying amounts of time to fly toward the short flash of light associated with the sweet food.

Davidson and Versace then tested the bees’ behavior when there was no food present, to rule out the possibility that the bees could see or smell the sugary food.

They found that the bees were able to tell the circles apart based on the duration of the flashes of light, rather than other cues.

“And so in this way, we show that the bee is actually processing the time difference between them to guide its foraging choice,” Davidson said.

“We were happy to see that, in fact, the bees can process stimuli that, during the course of evolution, they have never seen before,” Versace said, referring to the flashes of light.

“They’re able to use novel stimulus they have never seen before to solve tasks in a flexible way,” Versace added. “I think this is really remarkable.”

The researchers say bumblebees are one of only a small number of animals, including humans and other vertebrates such as macaques and pigeons, that have been found to be able to differentiate between short and long flashes, in this case between 0.5 and five seconds.

For example, this ability helps humans to understand Morse code, in which a short flash is used to communicate the letter “E” and long flash the letter “T.”

More than ‘just machines’

It is not clear how bees are able to judge time duration, but the team plans to investigate the neural mechanisms that allow the insects to do so.

The scientists are also planning to conduct similar research with bees that are able to move freely in colonies, rather than individually, and investigate the cognitive differences that allow some bees to learn to assess time duration faster than others.

Davidson hopes that the results will help people to appreciate that bees and other insects are not simple “machines essentially driven by instinct,” but rather “complex animals with inner lives that have unique experiences.”

“In fact, they do have complex cognition, this flexibility in learning and memory and behavior,” he added.

This may help people to perceive bees as more than unthinking pollinators, Versace said.

“They are not just machines for our purposes,” she said.

The findings also raise important ideas about our own understanding of time, according to Davidson.

“It’s such a fundamental part of our lives and the lives of all animals,” but we still don’t really understand what time is and how we deal with it in our minds, he said.

“I think this study is really interesting because it shows that it’s not just a human question,” Davidson said.

The researchers reported their findings Wednesday in the journal Biology Letters.

The study shows “that bees possess a sophisticated sense of time,” according to Cintia Akemi Oi, a postdoctoral research fellow at the Centre for Biodiversity and Environment Research at University College London. Oi was not involved in the new research.

“This finding makes perfect sense, as bees must carefully manage their time while foraging to maximize rewards and minimize the costs of returning to the nest,” she said.

“Such studies not only help to understand insect cognition, but also shed light on the shared and unique features of their neuronal functions, offering valuable insights to the field.”

Jolyon Troscianko, a visual ecologist at the University of Exeter in England, who was not involved in the study, told CNN that the results show that the bees “must be using learning that can measure the length of time.”

The method shows that bees can learn using information from outside their usual ecological context, “which I find fascinating as it demonstrates how this type of general learning can be achieved with brains many orders of magnitude smaller than the birds and rodents that prior work has focused on,” he said.

“Bigger brains are therefore not always necessary to show really impressive cognitive abilities.”

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