How humans adapted to digest lactose — after thousands of years of milk drinking
00:45 Working out how the ability to digest milk spreadHumans have been drinking milk for thousands of years, but it seems that they were doing so long before the ability to digest it became prevalent. Then around 2000 years ago, this ability became common in Europe, presenting a mystery to researchers – why then? Now by analyzing health data, ancient DNA, and fats residues from thousands of ancient pots, scientists have worked out what caused this trait to suddenly spread throughout Europe.Research Article: Evershed et al.News and Views: The mystery of early milk consumption in Europe08:56 Research HighlightsHow genes stolen from outside the animal kingdom have altered insects’ abilities, and a dormant black hole beyond the Milky Way gives insights into these objects' origins.Research Highlight: Genes purloined from across the tree of life give insects a boostResearch Highlight: A quiet black hole whispers its origin story11:21 Assessing the addiction potential for therapeutic ketamineKetamine has shown great promise as a fast-acting antidepressant, but there have been concerns about the risks of addiction relating to this therapeutic use. Now, a team have looked in mice to see whether ketamine causes the behavioural and neuronal changes characteristic of addictive substances. They find that ketamine likely has a low addiction risk, which could inform future prescribing decisions in humans.Research article: Simmler et al.News and Views: A short burst of reward curbs the addictiveness of ketamine17:51 Briefing ChatWe discuss some highlights from the Nature Briefing. This time, a report shows a significant decline in Australia’s environment and ecosystems, and how adding a gene greatly increases rice yield.The Conversation: This is Australia’s most important report on the environment’s deteriorating health. We present its grim findingsNature News: Supercharged biotech rice yields 40% more grainSubscribe to Nature Briefing, an unmissable daily round-up of science news, opinion and analysis free in your inbox every weekday.