In this episode: 00:46 Mapping ‘ghost roads’ in tropical forestsAcross the world, huge numbers of illegal roads have been cut into forests. However, due to their illicit nature, the exact numbers of these roads and their impacts on ecosystems is poorly understood. To address this, researchers have undertaken a huge mapping exercise across the tropical Asia-Pacific region. Their findings reveal over a million kilometers of roads that don’t appear on official maps, and that their construction is a key driver for deforestation. Research Article: Engert et al. 10:44 Research HighlightsHow climate change fuelled a record-breaking hailstorm in Spain, and an unusual technique helps researchers detect a tiny starquake. Research Highlight: Baseball-sized hail in Spain began with a heatwave at sea Research Highlight: Smallest known starquakes are detected with a subtle shift of colour 13:02 Briefing ChatA clinical trial to test whether ‘mini livers’ can grow in a person’s lymph node, and the proteins that may determine left-handedness. Nature News: ‘Mini liver’ will grow in person’s own lymph node in bold new trial Nature News: Right- or left-handed? Protein in embryo cells might help decide Nature video: How would a starfish wear trousers? Science has an answer Vote for us in the Webbys: https://go.nature.com/3TVYHmP Subscribe to Nature Briefing, an unmissable daily round-up of science news, opinion and analysis free in your inbox every weekday. Hosted on Acast. See acast.com/privacy for more information.