While insects are often viewed as simple creatures, the sophisticated behaviors of honeybees challenge this perception. With brains smaller than a sesame seed, the idea that a bee could perform complex mental tasks seems unlikely. This raises questions about their cognitive abilities and whether they include skills once thought exclusive to more complex animals.
Testing a Bee’s Numerical Ability
To determine if bees possess numerical skills, scientists trained them using a sugar solution as a reward. Bees were presented with platforms marked with a different number of symbols and were rewarded only for landing on a platform with a specific quantity. To ensure the bees were responding to the number of items and not other visual cues, researchers varied the symbols’ appearance.
The bees consistently chose the platform with the correct number of items, demonstrating an ability to count to small numbers like four. Further experiments explored whether bees could understand relative values, such as “more than” or “less than.” In these tests, bees were trained to choose the platform with either the greater or fewer number of items to receive a reward.
Bees successfully learned and applied these concepts across various tests, even with unfamiliar numbers of symbols. This ability to generalize rules suggests that their numerical sense is a flexible cognitive skill, not just rote memorization.
Understanding the Concept of Zero
Comprehending “zero” as a numerical value represents a more abstract level of thought. Scientists investigated this by first training bees to identify the smaller of two quantities. After learning the “less than” rule, bees were given a choice between a platform with one shape and a completely blank platform.
The bees showed a preference for the blank platform, correctly identifying it as having a lower value than one. They chose the empty set up to 70% of the time, a rate significantly higher than random chance. This demonstrated that bees could place zero at the correct end of a numerical sequence.
A control experiment confirmed the bees were treating zero as a quantity. A separate group trained on the “greater than” rule correctly avoided the blank platform when given a choice, showing it was not simply a preference for a novel target.
The bees’ accuracy also mirrored a pattern seen in humans, known as Weber’s law. They were more accurate when the difference between numbers was larger, distinguishing between zero and five more easily than between zero and one.
Implications for Insect Intelligence
The discovery of numerical abilities in bees has implications for how we view insect cognition. These skills likely provide an evolutionary advantage, aiding in foraging and navigation. For instance, a bee might count landmarks to remember the path to a patch of flowers or to communicate a food source’s location.
This research reveals that complex cognitive functions can emerge from small and efficient neural structures. The honeybee brain contains fewer than a million neurons, yet it can handle abstract concepts like zero. This suggests that brain architecture, not just its size, is a determinant of its computational power.
These findings encourage a broader re-evaluation of intelligence across the animal kingdom. The numerical abilities of bees open new avenues of research into the cognitive capacities of other insects and invertebrates.