Carlos Solis
This is the first documented case of an insect showing a clear reaction to food it “likes” or “dislikes.”
In the experiment, researchers offered water with different additives: solutions with varying sugar concentrations, a saline solution, or water with quinine, a bitter-tasting compound. After sipping the sweet solution, the bumblebees repeatedly extended their glossa, a tongue-like structure they use to draw up liquid.
- The sweeter the solution, the more often bumblebees displayed the behavior.
- With salty or bitter solutions, they shook their heads and seemed to wipe their faces — behaviors researchers took as signs of disgust.
- When kept without access to water, the bumblebees also extended their glossa toward plain or salty water, which suggests thirst influenced the reaction.
What Pharmacological Tests Found
To probe the mechanisms, researchers used pharmacological tools. They found that glossa extension wasn’t linked to dopamine-dependent food-motivation systems. Instead, the behavior was enhanced by an endocannabinoid neural system — the same system that, in mammals, contributes to the emotional evaluation of stimuli.
The authors emphasize that although a bumblebee’s brain is tiny and weighs less than a milligram, the insects display complex abilities: they solve puzzles, sometimes use simple tools, recognize human faces, count up to four, and even have a sense of zero. Previous explanations for those skills often framed bumblebees as little biological calculators.
Researchers now think watching facial movements during feeding could be a first step toward a fuller, multidimensional understanding of bumblebee psychology. “We do not yet know what bumblebees experience inside, but we can observe behavior that resembles emotion,” says co-author Professor Andrew Barron of Macquarie University. He says this gives scientists a practical tool for experimentally studying the insects’ internal state.
The team plans to study the link between brain activity and what might be called “subjective experience.” That work could explain how neural processes produce an inner life and help bridge the gap between physiology and mind. If their ideas hold up, the findings could change how we treat insects in nature and in agricultural practice.
Based on reporting by the Daily Mail
