In a recent study published in the US Proceedings of the National Academy of Science page, researchers found that ants can enhance their water repellency by linking their bodies together.

The study showed the reason why a single fire ant can struggle in the water. Though having a water repellent outer covering, a group of them can float effortlessly for days. Scientists found that ants link their bodies together to build waterproof rafts, by using their mandibles, claws, and the adhesive pads on the ends of their legs to grab onto each other.

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By freezing the ants, the Georgia Tech team observed that fire ants construct rafts when placed in water by gripping each other with mandibles, claw and adhesive pads at a force 400 times their body weight. The result is a viscous and elastic material that is almost like a fluid composed of ant “molecules,” researchers said. Credits: Georgia Tech

“While it sounds like something out of a horror movie, the technique by fire ants has been used for eons to escape flooding and migrate long distances, according to Tim Davis, an entomologist and Clemson University senior extension agent”, USA Today reports.

However, they are still in danger while in water, since they face constant danger from predators, particularly fish, who pick them off one by one.

Ants survive a flooding

Ants have used their ability to float in water for days during the South Carolina flooding by building “ant islands”. These insects have gathered their eggs, and weave rafts when the water started to rise.

“Although the raft is porous and its base is below the water level,” explained Lizzie Buchen from Nature, the international weekly journal of Science, “none of the ants are submerged, or even get wet. Instead, the ants at the base of the raft push against the water’s surface and shape it around them into a bowl without breaking the surface tension.”

However, people have not had the same luck after the South Carolina flooding. So far, at least 17 people have died in weather-related incidents: 15 in South Carolina and 2 in North Carolina.

Moreover, more than 400,000 state residents were under a “boil water advisory” affecting about 16 water systems, according to Jim Beasley, a spokesman for the S.C. Emergency Response Team, quoted by CNN. The state is now facing “billions of dollars” in damage.

Source: PNAS