By Mariam Malik ‘22

Some animals are mentally capable of understanding the concept of numbers, emotion, and even language. However, at RMIT University in Australia, an experiment done on bees shows that they are not only able to understand the concept of numbers, but they also show comprehension of arithmetic operations, such as addition and subtraction, with the use of colored symbols.

To determine if some animals are capable of numerical cognition, PhD researcher Scarlett Howard and his research team, chose to use honeybees because they have previously been shown capable of learning various rules and ideas to solve conflicts, for example, the idea of left/right, larger/smaller, front/behind, etc. When trained with rewards, bees have also shown an ability to count and distinguish between numbers. With this, the researchers’ goal was to train the bees to identify a common color, either yellow or blue, as a symbol of whether to use addition (blue) or subtraction (yellow), and then pick the correct result of the operation. Furthermore, the bees were trained to enter a Y-maze. First, they had to fly through an entrance hole that led them to a chamber where there would be a sample stimulus. Each color had its own maze and trial, since they represented two different operations. In the blue Y-maze for example, the sample stimulus in the chamber would show two blue shapes. Then they would fly through another hole to the decision chamber, with two holes on each side and different stimulus near each hole. With the blue Y-maze, one hole would show one blue shape and the other showed three blue shapes. The hole with the three blue shapes is the correct answer, since blue symbolizes addition and the sample stimulus had two blue shapes. The bees would then fly into the hole that had the correct answer fifteen centimeters away from it.

As reward or punishment for choosing the correct or incorrect answer, the bees were given a few drops of 50% sucrose solution or quinine solution. The results showed Howard and his research team that there was a significant increase in the number of bees that answered correctly, showing that bees were able to add and subtract by one depending on the color of the sample stimulus before the decision chamber.

The study showed that bees were mentally capable, despite their minuscule brains, of information processing, including the representation of numerical attributes and then using those representations in their working memory. From an ecological perspective, the bees’ ability to think arithmetically and remember is advantageous in remembering which characteristics of flowers (color, type, size) provide essential resources and which do not. This new finding brings new areas of research in the brains of insects, and whether this combination of arithmetic and learning ability based on symbolism is applicable to other species. More specifically, to other organisms with small brains, such as other insects.

References

1. S. R. Howard, et. al., Numerical cognition in honeybees enables addition and subtraction. Science Advances 5, (2019). doi: 10.1126/sciadv.aav0961.  
2. Image retrieved from: https://www.pexels.com/photo/animal-bees-bloom-blooming-553251/