How ant colonies make decisions as a neural network

Suppose the temperature in an ant nest increases. It is very hot under the feet of the ants. But they continue. And then suddenly: evacuation of the entire colony. How do they decide that?

Research shows that the response of ants to a similar stimulus can be compared to the functioning of a neural network, like our brain. The input of sensory information, in combination with the structure of the group, ensures that there is an output. In this case: evacuation.

To find out, the scientists studied a colony while controlling the temperature of the nest and monitoring all the ants individually. They saw that a small colony had enough at 34 degrees, but if the colony was bigger, they stayed longer. For example, a colony of 200 ants survived 36 degrees.

This shows that temperature is not the only trigger. The size of the group – and therefore also the difficulty of the evacuation – also plays an important role. But how does an ant know how many it is in a colony?

It must have something to do with the substances the ants use to communicate, the researchers speculate. In follow-up research, they want to influence these substances in addition to temperature to see what effect this has on a colony’s decisions.

Read more: Ant colonies behave like neural networks when making decisions.