Age no barrier to ant career advancement

Ants have flexible work arrangements. Keystone / Harish Tyagi

The division of labour in ant colonies has little to do with age but is apparently determined by random factors, scientists believe.

Female ants either take care of the queen and larvae inside the nest or venture out in search of food. Researchers at the University of Lausanne wanted to know if foraging duties were carried out only by older, more experienced ants.

By studying tens of millions of social interactions among 500 ants for 100 days, researchers found that age played no role in how an ant climbs up the corporate ladder.

Every female worker had exactly the same chance (around 3%) of promotion from the nursery to performing a foraging role.

“We are the first to show that role changes in an animal society are regulated by stochastic [random] processes. This discovery has important consequences for our understanding of the regulation of work in social insects,” said Laurent Keller, a professor at the university’s Department of Ecology and Evolution.

Randomness appears to be the most efficient way of ensuring the right balance between nursery and forager workers. Researchers also found that foragers would return to the nest to work in the nursery if conditions demanded this switch.

The results of the study have been published in the scientific journal Current Biology.