Animals shield their families from a harsh world

Animals living in volatile habitats can gain major evolutionary benefits by shielding their families from the changing environment, suggests research from UCL, the University of Bristol and University of Exeter. In a study , biologists investigated an overlooked reason for widespread cooperation amongst animals and found that when their environment is prone to fluctuate unexpectedly, staying at home to help raise relatives can be much better than going solo. By taking into account the turbulent nature of environments, the team showed that helping behaviour is much easier to evolve than previously thought: helpers don't need to be very closely related to those they help if the environment is really unpredictable. "We realised that help might actually only be of use to animals if the year turns out to be difficult because of bad weather or not enough food," explained co-author Dr Seirian Sumner (UCL Genetics, Evolution & Environment). "Helping relatives in bad years can have a huge effect on the number of grandchildren if it means your family does much better than others when times are hard. So it's worth siblings hedging their bets and staying at home." The study came about after biologists recently noticed that high levels of animal cooperation are often found in very harsh and unpredictable places - from birds on African savannahs to wasps in the sunny Spain. Patrick Kennedy from the University of Bristol's School of Biological Sciences, who led the study, said: "We wanted to find out whether evolution might work differently in these changeable habitats.