May 31, 2007  Army Ants Repair Roads Personally

Every commuter knows that hitting a pothole or slowing down to avoid others can make a driver cry uncle.  But ants have a remarkable solution to their own pothole problems, according to researchers at the University of Bristol in England.  And you can forget shovels or asphalt.  As vast columns of army ants head back to the nest after raids, some workers who mark the trail plug tiny potholes with their own bodies.  The ants straddle the potholes, creating a living bridge.  If it’s a particularly big hole, groups of ants link together to form a highway over the rough spot.    

Bigger ants carrying prey use the smoother surface to reach maximum speed, thus getting back to the nest as soon as possible to feed hungry youngsters.  After the valuable cargo has passed, the other ants climb out of the potholes and head home too.  And since army ant raids can contain up to 200,000 individuals, the speedy repair service by ants who are willing to get stepped on benefits the colony as a whole.  Now if the researchers can only figure out why cab drivers also seem to seek out potholes, but only so they can hit them as hard as possible.