A new study suggests that ants combine sensory information with the parameters of their group to make collective decisions, similar to how cells act in the brain.
The ants decide to evacuate their colony when the temperature reaches dangerous levels, similar to how a neural network works, researchers at the Rockefeller University in New York, USA discovered.
The study’s authors developed a system to test the reaction of an ant colony against changes in temperature. The results revealed that the decision of the insects to leave the anthill or not depends on two factors: the size of the colony and the degrees Celsius.
The experiment carried out by the researchers consisted of increasing the temperature inside a colony. The results revealed that, regardless of the heat, the ants, which feel the heat under their feet, did not change their behavior until the collective decision to run from the anthill was made. “It’s almost as if the ant colony has a larger, collective mind,” says the communiqué from the university.
But the researchers were surprised to discover that the ants’ decision was not only influenced by heat, but also by the number of individuals within the colony. When the group size, initially 36 ants and 18 larvae, increased to 200 individuals, increasing the temperature to 36°C was required to trigger decision making.
To reach such a conclusion, the researchers set up an experimental anthill equipped with a temperature control device and a surveillance camera, while the ants were marked with points of different colors to facilitate their monitoring, details the study published in the magazine Proceedings of the National Academy of Sciences.
How can the decision depend on the size of the colony?
On their own, the ants are unaware of the size of their colony, but they are able to communicate with each other by transmitting pheromones the greater the amount of this substance in the air, the greater the concentration of insects. According to scientists, this phenomenon is explained by the way in which pheromones potentiate their role as “invisible messengers” when more ants are present.
The team of biologists plans to continue your research by testing your findings on other parameters, including manipulation of pheromone levels.