Researchers Teach Bumblebees to Understand Morse Code

Intelligence is measured neither by the weight of a brain nor by the size of a body. Certain insects, even though they lack a cortex, manage to accomplish tasks that were thought to be reserved for vertebrates. Their environment, apparently limited, hides much broader cognitive capacities than imagined. Temporal cognition in bumblebees offers a striking demonstration of this, revealing a sense of time where one would only expect reflexes.

Flashes of light to test the memory of time

In a London laboratory, researchers designed an experiment worthy of a test of human intelligence. Bumblebees
Bombus terrestris were placed in a small maze connected to their hive by transparent tunnels. At each stage, they had to choose between two flashing yellow circles, one emitting a brief light, the other longer. One hid a sweet reward, the other a bitter quinine solution. After several trials, the insects began to recognize the duration of the flash associated with the sugar, regardless of its position.

This success proves that they did not only react to an odor or light intensity, but also to the notion of duration. When the rewards disappeared, the majority of bumblebees continued to move toward the light cue they had learned to associate with food, as if they were remembering the rhythm rather than the substance. According to the study published in Biology Letters, this statistically significant performance demonstrates active discrimination between short and long signals.

“It’s a fascinating discovery,” summarizes Alex Davidson, researcher at Queen Mary University of London. “Bumblebees never encounter flashing lights in nature, yet they understand this temporal logic.» Such a capacity, previously observed only in animals with much larger brains, suggests the existence of a sense of time shared between very distant species.

Temporal cognition in bumblebees, an underestimated talent

Until recently, time perception seemed the preserve of vertebrates. Macaques, pigeons and even rats are capable of evaluating the duration of a stimulus. But the discovery of this temporal cognition in bumblebees opens a gap. Their brain, the size of a poppy seed, contains barely a million neurons, compared to nearly eighty-six billion in humans. Despite this dizzying difference, they succeed in processing the abstract information that is the length of a signal.

The researchers wanted to make sure that the bumblebees weren't simply relying on the amount of light they received. In a second test, they equalized the total lighting duration of the two signals, changing only their rhythm. The insects have done it again. This time, only the perception of the passage of time could serve as a clue.

This ability is not anecdotal. It completes an already rich range of astonishing behaviors. We observe among them collective learning, problem solving, and even shape recognition. It even happens that they imitate each other. As Sciencealert explains, these discoveries are gradually moving the boundary between instinct and true learning.

Towards a new definition of insect intelligence

If a bumblebee can learn to “read” a time code, it is because its brain operates according to universal principles of neuronal economy. The team led by Elisabetta Versace suggests that the measurement of time could be a fundamental property of the nervous system, present in the simplest circuits. Neurons would not need specialized tools to process duration. Their intrinsic activity would be enough to encode the passage of time.

This type of experience now inspires researchers in robotics and artificial intelligence. Understanding how an insect encodes the duration of a signal with so few resources could help design leaner and more efficient artificial neural networks. As Eurekalert points out, bumblebee cognition demonstrates that great complexity is not necessary to accomplish an abstract task.

In a world where the boundaries between nature and technology are disappearing, bumblebees are a reminder that intelligence does not need a large brain to manifest itself. Sometimes a simple flicker of light is enough to reveal the depth of a miniature mind.