GEN-ERIC News

Ants not only work hard and are prepared to lay down their lives for their fellow ants, they also take bigger risks for the good of the colony as they get older – and they can even assess how much time they have left in life. Dawid Moron and his colleagues at Jagiellonian University in Poland have carried out a set of laboratory experiments showing that ants have the ability to gauge the end of their lifespan and to use their assessment of imminent mortality to take bigger risks with their ageing lives. It is well established that worker ants tend to take greater risks as they get older. Scientists have shown that this behavioural trait benefits the colony because certain risky activities, such as foraging far from the nest, are best done by ants coming to the end of their useful lives – it doesn’t pay to put young workers in high-risk jobs. As a result, younger ants tend to do housekeeping chores around the nest, which is inherently safer than travelling further afield. One remaining question, however, was whether ants had some internal mechanism that told them how old they were and how much time they had left before dying. Dr Moron believed that it might be possible to manipulate an ant’s lifespan artificially, and to observe changes to its risk-taking behaviour as a result. His study, published in the latest issue of the journal Animal Behaviour.