When the number of ants increases on a path, their flow increases in turn to achieve a certain constancy, unlike humans who themselves, beyond a certain threshold of density, slow down to cause a plug. Explanations.
In human societies, traffic congestion perfectly illustrates the problem associated with too much concentration of people traveling in the same space.
In ants, however, the movements of many of them do not seem to create traffic problems, even when the traffic is extremely dense. A reality that allows them to not interfere with their food harvest.
Observe to understand
American researchers (University of Arizona), French (University Toulouse III – Paul Sabatier) and Australians (University of Adelaide) wanted to understand how large ant colonies manage to move without losing efficiency.
To do this, biologist Laure-Anne Poissonnier and her colleagues conducted 170 filmed experiments in order to observe the ant traffic between their nest and a food source.
They sometimes changed the width of the road and the number of ants (from 400 to 25 600) to get there.
Did you know?
There are more than 20,000 ant species worldwide.
Surprise on the way
Ants accelerate to reach the maximum capacity of individuals that the road can withstand. When the density becomes too great and the collisions between ants are too numerous, ants change their strategy: they prefer to avoid collisions, synonymous with delays, rather than continue to accelerate.
Humans themselves, beyond a certain threshold of density, slow down to have a zero flow, which causes a traffic jam.
However, the authors of this work published in the eLife review also found that when the density becomes too high, the ants stop committing to the road, preferring to wait for the right moment for the make.
It should be noted that while ant traffic has many similarities with pedestrian and vehicular movements, it is also based on fundamental differences.
These insects are protected by their exoskeleton and do not fear shocks. This reality allows them to accelerate, while humans must slow down to avoid accidents and injuries.
Another important detail must be considered: the colonies share a common goal during their travels, namely the harvest of food. For this reason, they have an interest in not losing efficiency, whatever their density.
They are constantly adapting their rules of movement according to the local density, while the motoring of humans, it must submit to rules imposed as red lights, which inevitably have an effect on the traffic.