Having a helper to assist with the childcare doesn’t just make life easier for superb fairy-wren mothers, it can give them longer lives and enable them to breed more, according to research published in Science today.

Dr Naomi Langmore, a Postdoctoral Fellow at The Australian National University and member of the team that made the discovery, said that in many animal species, parents caring for their offspring are assisted by ‘helpers’ - adults that forego reproduction to help others raise young.

“In some bird species, helpers deliver lots of extra food to dependent young, but the offspring don’t appear to gain any advantage as a result. We were interested in finding out who really benefits from helping behaviour,” Dr Langmore said.

“Helpers relieve some of the burden of childcare for mothers, providing so much extra food to the chicks that mothers can get away with laying small eggs and conserving their energy for future breeding.”

“In the superb fairy-wren, mothers gain more from helping behaviour than their offspring. Helpers provide chicks with so much additional food that mothers can afford to skimp on nourishing their eggs.

“Females that are assisted by helpers lay smaller eggs with disproportionately small yolks, thereby saving energy during egg laying. As a result, they are able to live longer and breed more often than females that have no helpers.”

The paper "Reduced Egg Investment Can Conceal Helper Effects in Cooperatively Breeding Birds," was published today in Science. The research was carried out by a team from the Universities of Cambridge and Sheffield in the UK, and The Australian National University, University of New South Wales and Wollongong University in Australia. It was funded by The Australian Research Council, the Leverhulme Trust, and The Royal Society.

More information: Jane O’Dwyer, ANU Media Office, 02 6125 5001 or 0416 249 231