Listen to the latest science news, with Benjamin Thompson and Nick Petrić Howe.

In this episode:

00:45 Working out how the ability to digest milk spread

Humans 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 2,000 years ago, this ability became common in Europe, presenting a mystery to researchers — why then? Now, by analysing 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 Europe

08:56 Research Highlights

How 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 boost

Research Highlight: A quiet black hole whispers its origin story

11:21 Assessing the addiction potential for therapeutic ketamine

Ketamine 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 has looked in mice to see whether ketamine causes the behavioural and neuronal changes characteristic of addictive substances. It finds that ketamine probably 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 ketamine

17:51 Briefing Chat

We 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 findings

Science: Supercharged biotech rice yields 40% more grain

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