Thaindian News

London, April 27 (IANS) Ants, with their pint-sized brains, avoid mass drownings by clinging to one another forming live rafts.

The remarkable survival strategy belongs to South American fire ants, whose rain forest homes are subject to regular flooding.

As soon as water starts trickling into their nest, the ants spring into action, evacuating their home and drifting along en masse, looking for higher ground, reports the journal Proceedings of the National Academy of Sciences.

Now, American scientists have shown just how they do it.

After collecting fire ant colonies from roadsides in Atlanta, they conducted a series of experiments into water repellency, buoyancy and building skills and speed, according to the Daily Mail.

Some simply involved dropping hundreds, or thousands, of the reddish-brown bugs, on top of water and then using time-lapse photography to track what they did next. In some cases, it took them less than two minutes to clump into floating “rafts”.

The “rafts” were roughly the shape of a pancake loaded with topping, with approximately half the colony forming a single submerged layer that buoyed the rest.

The creatures used their jaws and claws to cling together in a formation similar to the weaving of a waterproof fabric.

Researchers, from the Georgia Institute of Technology, said this suggests that the submerged ants are able to somehow sense how many “passengers” are riding along above.

Around 100 ants are needed to begin to form a raft - and in the wild, the structures can float along for weeks or even months.

Researcher Nathan Mlot, doctoral student, said: “It doesn’t matter if you have part of a colony, or the entire colony, all of the rafts are watertight.”

The queen, and her young are also carried on board and kept safe and dry during the voyage.

However, the adhesion process falls apart in soapy water, with lack of water pockets making raft construction impossible.