Researchers trained Bombus terrestris bumblebees to distinguish long and short light flashes — a simplified Morse-like code — to find sugar. Bees learned to discriminate durations (e.g., 5s vs 1s; 2.5s vs 0.5s) and reached a criterion of 15 correct choices out of 20. When rewards were removed, bees still favoured the timing linked to sugar, showing they encoded temporal information rather than relying on scent. The study, published in Biology Letters, suggests surprising temporal-processing ability in very small brains.
Bumblebees Learn a Morse-like Light Code — Revealing Surprising Time Perception in Tiny Brains
Researchers trained Bombus terrestris bumblebees to distinguish long and short light flashes — a simplified Morse-like code — to find sugar. Bees learned to discriminate durations (e.g., 5s vs 1s; 2.5s vs 0.5s) and reached a criterion of 15 correct choices out of 20. When rewards were removed, bees still favoured the timing linked to sugar, showing they encoded temporal information rather than relying on scent. The study, published in Biology Letters, suggests surprising temporal-processing ability in very small brains.
01:24 PM, 11/12/2025Science
Bumblebees learn a Morse-like light code
In a clever set of experiments, researchers trained the buff-tailed bumblebee (Bombus terrestris) to distinguish between long and short flashes of light — a simplified, visual analogue of Morse code — in order to locate a sugary reward. The study, published in Biology Letters, provides the first clear evidence that these bumblebees can base foraging decisions solely on the duration of a visual cue.
How the experiment worked
Bees were placed in a small foraging arena where a screen showed two flashing lights: one with a longer duration and one with a shorter duration. In some trials the team compared 5-second pulses with 1-second flashes; in others they used 2.5-second versus 0.5-second blinks. One duration signalled a sugary reward, while the other was paired with quinine, a bitter compound bees avoid. Different bee groups experienced opposite pairings so the association was not fixed.
Learning and testing
During training, bees learned to navigate the arena until they reached a criterion of 15 correct choices out of 20 attempts. To ensure the insects were responding to timing rather than scent or other cues, the researchers then removed the rewards. Even without sugar present, bees chose the timing pattern previously linked to the reward significantly more often than chance, indicating they had encoded duration information rather than merely following odour cues.
“We wanted to find out if bumblebees could learn the difference between these different durations, and it was so exciting to see them do it,” says behavioral scientist Alex Davidson of Queen Mary University of London.
Why it matters
Recognizing the length of a signal — temporal processing — can help animals with foraging, mating decisions and avoiding predators. That bumblebees can discriminate durations suggests temporal information processing is more widespread across animal taxa than previously appreciated. The authors propose two nonexclusive possibilities: either bees repurpose neural timing mechanisms evolved for other tasks (for example, tracking motion), or time processing is an intrinsic property of nervous systems even in very small brains.
This result also reinforces a growing body of evidence that complex cognitive abilities can occur in extremely small brains — sometimes no larger than a poppy seed — and that capacities once thought uniquely human are often distributed more broadly across the animal kingdom.
Next steps
Future work will need to determine the neural mechanisms underlying timing in insects and whether bees use duration cues in natural contexts. For now, the findings open exciting new questions about how tiny brains represent time.
Study: Davidson et al., published in Biology Letters.