A new variant of coronavirus which originated in India is spreading rapidly. The team explains how both this new mutation and the UK variant are capable of evading vaccines, causing huge concerns for the global fight against covid-19. They also discuss whether the risks of solar geoengineering outweigh the benefits, as new research in the journal Nature Food looks at the potential impact on agricultural yields. They discuss a revolution taking place in archaeology as the discipline absorbs modern techniques from genetics, speaking to anatomist Alice Roberts about her new book Ancestors: The Pre-History of Britain in Seven Burials. They hear the calls of red-handed tamarin monkeys who change their accents when they move in with a neighbouring species. And they discuss the extraordinary news that a man who was once blind has had his sight partially restored thanks to optogenetics. On the pod are Rowan Hooper, Tiffany O'Callaghan and Michael Le Page. To read about these stories and much more, subscribe at newscientist.com/podcasts. Our GDPR privacy policy was updated on August 8, 2022. Visit acast.com/privacy for more information.