Army ants act like algorithms to make deliveries more efficient

The marauding ants know just where to place living bridges to create short-cuts without sacrificing their food-gathering prowess.

To optimize its delivery drones, maybe Amazon could take inspiration from the actual Amazon.

Army ants in Central and South America aggressively seek out the shortest path over the forest floor to bring home enough food and ensure the future of their colony. This focus on efficiency led the insects to develop a clever trick: They link their bodies together to fill potholes and build living bridges.

As more ants join in, the bridges shift locations to span larger and larger gaps, shortening the path ants have to take when carrying food back to the nest. But because each brick in the bridge is also a lost forager, the ants reach a point where a slightly better short-cut just isn’t worth the cost, according to new analysis of this insect construction work.

“Overall, that cost-benefit trade-off is reached, but without any ants really knowing,” says study leader Chris Reid of the University of Sydney.

Source/read more Smithsonian Mag

Citation Chris R. Reid, Matthew J. Lutz, Scott Powell, Albert B. Kao, Iain D. Couzin, and Simon Garnier. Army ants dynamically adjust living bridges in response to a cost–benefit trade-off, PNAS, Published online before print November 23, 2015, doi: 10.1073/pnas.1512241112