Why are ants so crowded, but their whole nest never gets in traffic?

If you've ever observed a colony of ants moving, you'll find they never get stuck in traffic. Ants are the masters of man in organizing collective traffic flows.

A new study in eLife shows that ants can keep a stable traffic flow on a bridge, even if it has reached 80% of its capacity. In comparison, a human bridge hitting the 40% capacity threshold has slowed traffic flow.

What is the secret of ants?They simply put the interests of the whole team first. Ants often sacrifice part of their personal interests in traffic, but that makes the whole system more efficient.

On the contrary, people always have an inherent conflict between personal interests and collective interests. That is the main reason causing traffic congestion and increasing the total travel time of the whole society, even if we have implemented many solutions, seemingly as effective as expanding roads.

Ants are a prime example of collective behavior.

Traffic in the ant species world

Ants are a prime example of collective behavior . If you observe a few ants apart, they will behave as individual ants individually. But if they were brought close enough, to a certain number, the ants would work in groups, becoming a single unit, both disciplined and flexible enough.

There have been several studies over the last decade that address the collective behavior of this interesting insect.

For example, in 2008, German scientists built ants a small system of motorways in the lab. It also contains intersections, junctions, and intersections that separate ants from their food source. Then they watched how the ants found the shortest way to get there.

If you were a human, would you think traffic congestion would definitely occur at intersections? But with ants, this phenomenon absolutely does not occur. Instead, whenever a route starts to get clogged, the ants returning to the nest block the ants in the opposite direction, forcing them to find an alternate route.

Last year, the physicist Daniel Goldman's lab at the Georgia Institute of Technology also studied how fire ants optimize tunneling. These tunnels are narrow, only enough space for two ants to pass, but congestion rarely occurs.

That's because the ants face a tunnel, in which the other ants are working, it immediately withdraws to find another tunnel.

Ants often sacrifice personal interests to put the interests of the whole team first.

In a new study in eLife, scientists at the Center for Animal Awareness at the University of Toulouse and the University of Arizona designed an experiment with Argentine ants (Linepithema humile).

They raise ant colonies of different sizes, with the smallest being 400 and the largest being 25,600. To observe the traffic behavior of these ants, scientists have created a unique path from their nest to the food source.

It is a bridge that can vary in width from 5 mm, 10 mm to 20 mm. The size of the ant population and the width of the bridge will allow scientists to control the density of traffic passing through it.

A total of 170 experiments were conducted to observe traffic flow (the number of ants per unit area per unit of time), the velocity of ant movement and the number of times they collided with each other.

As a result, the scientists found that the traffic volume still reached a good and stable threshold, even when the bridges reached 80% capacity. For comparison, for pedestrians or drivers, traffic volume begins to slow down when the capacity exceeds 40%.

So what is the secret of the ant? Right at the time the traffic density became crowded, they adjusted themselves, adapting the " rules " when necessary.

The ants can keep the traffic on a bridge stable, even if it has reached the threshold of 80% capacity.

The authors write:

"As the road density increases, ants seem to be able to assess the local crowds around them and adjust their speed accordingly, avoiding any disruption to the flow of traffic.

Moreover, the ants have prevented themselves from going into a crowded road, ensuring never to exceed the capacity of the bridge [the maximum flow allowed by the width of the bridge] ".

Conflict of personal and collective interests

It must also be said that ants never encountered the same annoying trouble in traffic, such as a red light turned on while the other two sides of the intersection did not have any vehicles.

But that is not the main reason why the ant transport system works much more smoothly than humans. The authors argue: " Traffic jams are ubiquitous in human society, where each individual is only pursuing their own goals . "

There is an inherent conflict of interest between what benefits us individually and what benefits the whole society.

"In contrast, ants have a common goal: the existence of a whole nest , so common sense they will work together to optimize the amount of food brought back," the scientists wrote. The more effective the traffic is on the entire route, the more ants can bring back to the nest.

The two charts compare the flow of traffic, the speed of movement and the number of collisions of ants (green) and people (red) as the traffic density increases.

In 2008, a study found that the conflict of interest of individuals with the whole society has increased our average travel time by 30%. That is one reason why the expansion of the highway also does not reduce traffic congestion for human society.

If we want to learn about ants, an effective way is to block some of the streets as needed, to prevent traffic from continuing to flow into an overloaded road. As with ants, this will ensure no path exceeds capacity. When some roads are blocked, the driver will have to find the other way for himself, similar to what ants are doing.

In fact, ants have a lot of things that make us admire and learn. An ant colony is a system of very effective interacting individuals, where researchers can find similarities in molecular biology theory, statistical physics, telecommunications, and many other fields. .

About the secret of creating an efficient transport network for ants, scientists say we can learn their principles of cooperation , the knowledge that will one day allow us to build a The public transport system and self-driving cars provide a common effect for the whole society.

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