Ants wise enough to quit when their teeth wear out

LONDON - Ants have a well-deserved reputation for strength, organisation and teamwork. But a key to their success is the ability to identify the importance of age in the work place.

A study of Central American leaf-cutter ants has shown that the younger and more vigorous members of the colony are given the toughest job of cutting through the leaves they harvest, the journal Behaviour Ecology and Sociobiology reports.

Their sharp young teeth do this job efficiently, but as they get older their teeth become relatively worn and blunt, according to the Daily Mail.

Accordingly, the former chompers are assigned to become carriers — transporting the leaves back to the colony where they are harvested for food.

Like humans, these insects recognise that older members of the group can still make a worthwhile contribution to society.

The findings by researchers from the University of Oregon and the Oregon State University supports previous research showing the survival of a leaf-cutter colony depends on the efficiency of its workers.

“Cutting leaves is hard work,” said Robert Schofield, who led the team of US scientists.

“Much of the cutting is done with a V-shaped blade between teeth on their mandibles. This blade starts out as sharp as the sharpest razor blade that humans have developed,” Schofield said.

But over time, the teeth become blunter and the cutting job slows down.

The team estimated that because of this age-related wear, a colony spent twice the energy cutting leaves than it would if all the ants had sharp mandibles.