Honeybees make fast, accurate decisions

A new study published in the journal eLife elucidates the honeybees behavioral strategy to associate sensory cues with rewards of different values. Based on solid experimental evidence, the study demonstrates how sensory evidence and reward likelihood quantitatively affect the decision-making process and the bees’ response time. The behavioral paradigm and the proposed model could provide interesting insights for scientists studying decision-making in higher animal species.

In the natural world, decision-making processes are often intricate and challenging.

Animals frequently encounter situations where they have limited information on which to rely to guide them, yet even simple choices can have far-reaching impact on survival.

Each time a honeybee sets out to collect nectar, for example, it must use tiny variations in color or odor to decide which flower it should land on and explore.

Each ‘mistake’ is costly, wasting energy and exposing the insect to potential dangers.

To learn how to refine their choices through trial-and-error, bees only have at their disposal a brain the size of a sesame seed, which contains fewer than a million neurons. And yet, they excel at this task, being both quick and accurate.

The underlying mechanisms which drive these remarkable decision-making capabilities remain unclear.

“Decision-making is at the core of cognition,” said Macquarie University’s Professor Andrew Barron.

“It’s the result of an evaluation of possible outcomes, and animal lives are full of decisions.”

“A honeybee has a brain smaller than a sesame seed. And yet she can make decisions faster and more accurately than we can.”

“A robot programmed to do a bee’s job would need the back up of a supercomputer.”

“Today’s autonomous robots largely work with the support of remote computing,” he added.

“Drones are relatively brainless, they have to be in wireless communication with a data center.”

“This technology path will never allow a drone to truly explore Mars solo — NASA’s amazing rovers on Mars have traveled about 75 km in years of exploration.”

In their study, Professor Barron and his colleagues aimed to explore which strategies honeybees adopt to forage so effectively, and the neural systems that may underlie them.

“We trained 20 bees to recognize five different colored flower disks,” said University of Sheffield’s Dr. HaDi MaBouDi.

“Blue flowers always had sugar syrup. Green flowers always had quinine (tonic water) with a bitter taste for bees. Other colors sometimes had glucose.”

“Then we introduced each bee to a ‘garden’ where the ‘flowers’ just had distilled water.”

“We filmed each bee then watched more than 40 hours of video, tracking the path of the bees and timing how long it took them to make a decision.”

“If the bees were confident that a flower would have food, then they quickly decided to land on it taking an average of 0.6 seconds).”

“If they were confident that a flower would not have food, they made a decision just as quickly.”

If they were unsure, then they took much more time — on average 1.4 seconds — and the time reflected the probability that a flower had food.

The authors then built a computer model from first principles aiming to replicate the bees’ decision-making process.

They found the structure of their computer model looked very similar to the physical layout of a bee brain.

“Our study has demonstrated complex autonomous decision-making with minimal neural circuitry,” said University of Sheffield’s Professor James Marshall.

“Now we know how bees make such smart decisions, we are studying how they are so fast at gathering and sampling information.”

“We think bees are using their flight movements to enhance their visual system to make them better at detecting the best flowers.”