A recent study at RMIT University, Australia, led by Scarlett Howard and Adrian Dyer, has demonstrated the ability of honey bees to distinguish between numbers, suggesting that they are more accomplished at quantity evaluation than previously thought.
The study, which was also conducted by Jair Garcia, Andrew Greentree, and Aurore Avarguès-Weber, took place in France, in April, to ensure enough bees would be present for a representative sample size. It involved a Y-shaped maze and two groups of honey bees. Each end of the maze featured a different card: one with four shapes, and one with a number of shapes ranging from one to ten, with four treated as the “correct” response. In the first group, bees that selected the correct response were rewarded with a sip of sugar water, and given plain water when the other option was chosen. In the second group, the plain water was replaced with a bitter-tasting quinine-water.
Once the bees had been trained to choose four, the researchers made the other option more specific: the subjects had to choose between a four-shape card and an eight-shape card each time, with their success – or lack thereof – recorded. Then, over several stages, the shape numbers on the two cards became closer together. After four and eight, the bees chose between four and seven, and so on.
The results, published in the Journal of Experimental Biology, indicated that using quinine water as a response to the wrong choice, instead of plain water, was a better method of training, as the honey bees in this group were more successful in distinguishing between numbers, including between four and five – the most difficult comparison. By contrast, the other group’s subjects struggled to differentiate between four and eight. The conclusions of the new study shows that honey bees can learn the rules of “less than” and “greater than” and can then apply these rules to evaluate numbers from zero to six. Previous studies had shown that they were capable of distinguishing between three and four, similar to other creatures such as angelfish and guppies. However, this research also suggested that honey bees struggled with quantities between four and five, possibly due to the use of plain water rather than quinine water for incorrect choices. The earlier method simply rewarded the correct decision, whereas the new method also dissuaded the honey bees from selecting the wrong option, further reinforcing the training.
In addition to the mathematical skill demonstrated in this experiment, honey bees have a wide range of abilities. They are known for their methods of communication with one another, through chemicals, odours, and a dance “language”, all of which can direct other bees to a particular location. They defend each other and their hives through the use of stingers, warning pheromones, and even heat – through the muscle vibrations of worker bees – when attacked by hornets or intruding queens.
Recent studies indicate that they can recognise human faces and that they can learn simple tasks by copying the behaviour of other bees. All of this suggests that, despite their relatively tiny brains, honey bees could be surprisingly intelligent.
The extent of the maths skills of honey bees is, as of yet, unclear: further study on their quantity evaluating abilities is being planned at RMIT University. Also unclear is where and how they may use these skills throughout their lifetime: it could range from hive-building to facial identification, or even another area entirely.
Image: C J Sharp via Wikimedia Commons