We can’t reverse the slow march of time, but thanks to the wonders of technology and modern medicine, we have a lot more of it in our lives. But as people live longer, and the birth rate declines, how are we going to manage a world with an ageing population?That one of the questions Sarah Harper, Professor of Gerontology at the University of Oxford, has been trying to find an answer for.She talks to BBC Science Focus editorial assistant Helen Glenny about how we cope with dramatic shifts in population, what effect it has on natural resources and climate change, and a quirk in our retirement age that suggests we should start drawing our pension aged 103.How Population Change Will Transform Our World by Sarah Harper is available now (£9.99, OUP)Listen to more episodes of the Science Focus Podcast which we think you will find interesting:Can we slow down the ageing process? – Sue ArmstrongHow can we save our planet? – Sir David AttenboroughIs religion compatible with science? – John LennoxWhat does it mean to be happy? – Helen RussellThere is no Plan B for planet Earth – Lord Martin ReesHow emotions are made – Lisa Feldman BarrettFollow Science Focus on Twitter, Facebook, Instagram and Flipboard Hosted on Acast. See acast.com/privacy for more information.