Living Bridges of Army Ants are Dynamic, but Dependent on Cost-Benefits

November 27, 2015 / No Comments

We do know the prowess of army ants in building live bridges threaded by merging their bodies. But we thought they were static bridges, like the normal human constructions which hold the structure strong.

Ants bridge e1448627690702 Living Bridges of Army Ants are Dynamic, but Dependent on Cost Benefits

But a recently published study proves that it needn’t be the case. Dr. Christopher Reid, lead co-author of the study, explains that these bridges can evolve to form new shapes and sizes depending on the requirements, meaning that it could expand further with the merging of more ants.

The case of a wedge shaped gap explains this well. The initial pathway for the living bridge is located closed to the angled intersection. But that won’t remain static; ants come on fusing with the bridge to broaden the pathway for its commodores, further narrowing the distance they have to cross.

This, according to the researchers, is not an ever expanding process. What we expect normally is that the process would come to a halt when it offers the best possible shortcut for the rest to pass through. But the expansion of these living bridges was found to be terminated even before that, raising the question of what the stoppage factor could be.

Researchers are currently looking to solve this puzzle. A brief speculation by them is that it could be due to the thoughts of cost and benefits. The parameter is visible not just in expansion, but also in the construction of a shorter bridge, in which the plan is dropped when they find that more ants have to be involved with the bridge to cover a short distance.

Similarly, the expansion might also be grinding to a halt when they find that the bridge have to expanded at the cost of the army count. This leads to the formation of a living bridge and doesn’t seem the shortest way, but yet holds the best shortcut they could construct considering the cost-benefit parameters.

Besides dealing deep with the bridging technology, the authors also bring to light the technology that could be handy in robotic technology, where it can be used to provide assistance when in scenarios of calamities and disasters.

The entire study can be read from the Journal Proceedings of the National Academy of Sciences.