Some species cooperate and distribute the work load among all the members of their colony. Only those species with a highly developed social organization can display such behaviours. Bees do.
During the sixties scientists started studying bees. They noticed how not only them, but also other insects and animals tend to organize their colony on a higher level of organization. This concept is now part of ethology and is known as eusociality. However, single eusocial insect behaviour is a relatively new field for the scientific community, so we still do not fully understand how social insects divide tasks.
Ecologists Alexander Walton and Amy L. Toth published a study in 2016 about the way each worker honey bee’s behaviour can vary from one specimen to the other, and whether or not that can be interpreted as a sign of personality. They hypothesized three dimensions of personality for honey bee Apis Mellifera and tested them.
Let’s see in detail what these dimensions are about. Firstly, each bee consistently behaves in a different way. Secondly, in different situations, bees keep their behavioural differences. Lastly, every bee shows a preference for a different set of activities.
There is another aspect they considered before starting the experiment. Bees in different stages of life bear different responsibilities inside the colony. When they are young, they tend to perform indoor tasks such as taking care of larvae, building and keeping the hive clean. As they age, they start going out more, looking for food and keeping the hive safe from possible threats. For this experiment, Toth and Walton picked bees of the same age. This way, they could rule out the age-related variable.
The first two dimensions were put to test in an artificial setting. The authors tracked the behaviours of every single bee – they used coloured paint to mark them. They exposed the bees to a series of tests every other day. They slid different pheromones inside the cage to see how the bees would react. They also put a bee from another colony inside the cage, which was considered as an intruder. The third dimension was tested on a real hive. Even though this setting was slightly harder to manage, the authors tried – and succeeded – in observing how the bees behaved in their natural habitat.
This study provides evidence in favour of all three dimensions of worker bee personality. Their data shows how some bees prefer tasks where they can interact with other workers. For example, they may enjoy food sharing. In other words, some bees are more “sociable”, while others might prefer being own their own.
These findings contribute to creating a more accurate model of the work organisation among worker bees. It also provides proof of the fact that some behavioural differences are not related to age. This means that personal preferences contribute to better divide labour inside the colony.