Ants in tropical forests of Central and South America link their bodies together to create living bridges for the other ants to march across whenever they encounter a gap in their path, according to researchers.
In the new study – published Monday in the journal Proceedings of the National Academy of Science – the researchers found that besides cooperating with each other, the ants also appeared to weigh the benefits and costs of making a longer bridge.
When two many ants were required to build a short-distance bridge, the army ants decided that it was not worth it, the researchers found.
Army ants are known to build bridges that begin at the intersection of material that insects typically walk on, like vines or sticks. To build and extend the bridge across a gap, they continuously add more bodies. However, when army ants sense that their overall progress is in fact slowing down after using so many bodies, they stop building the bridge.
Dr. Christopher Reid, co-author of the study and a postdoctoral researcher at the University of Sydney’s Insect Behaviour and Ecology Lab said that the stopping came as a surprise to him and fellow researchers. In most cases, the ants could have continued to build the bridge to create a better shortcut, Dr. Reid added.
To look at the army ants in action, the researchers created angular gaps in the ants’ path using boards, which they placed on the rainforest floor. As expected, the ants used their bodies one-by-one to build the living bridge.
The army ants were positioned on the side of the bridge that was furthest from the crook in the gap; but they stopped building the bridge at one point.
Dr. David Hu, an associate professor of Mechanical Engineering and Biology, and adjunct associate professor of Physics at Georgia Institute of Technology, said that he expected the ants to choose the shortest path possible.
According to Dr. Hu, the bridge building skill of army ants could help develop better technological systems, such as autonomous robotic swarms. Such swarms could perform tasks like building supports to stabilise a falling structure, bridges over a complex terrain, or plugs to fix breaches, he explained.
Image Source: teambuildingmanila