Lazy Ants

Scientist at Work - Anna Dornhaus - Researcher Studies Ants and Bees, One by One - NYTimes.com

Dr. Dornhaus found that fast ants took one to five minutes to perform a task — collecting a piece of food, fetching a sand-grain stone to build a wall, transporting a brood item — while slow ants took more than an hour, and sometimes two. And she discovered that about 50 percent of the other ants do not do any work at all. In fact, small colonies may sometimes rely on a single hyperactive overachiever.

Why do some worker ants lean on their shovels and let the rest of the workers do all the work? “It’s like students living together — you’ll always find one will have a lower threshold for doing the washing up and will end up always doing it all,” she said.

Perhaps the division of labor — which the economist Adam Smith linked to human achievement — may not be the key to ant success. Possibly, Dr. Dornhaus said, “the lazing ants are resting, or are waiting in reserve in case something goes wrong.” Or the laggards may be cooking up some biochemical nest protection. (All ant species manufacture a fungicide to stave off mold in their nests.) Or, she said, “It’s possible they aren’t doing anything at all.”