As the planet faces unprecedented human-caused global heating, heads of government are meeting in Turkey for the next fortnight for the latest round of climate talks. Madeleine Finlay tells co-host Ian Sample why these negotiations are so critical and what the chances are of meaningful change.

Social media is awash with claims iron deficiency can be identified in the mirror by dark circles, breaking hair and dry skin. But is ‘ferritin face’ real? Madeleine Finlay tells Ian Sample why so many of us struggle to keep our iron levels up, how we can actually diagnose low iron and the best way to correct a deficiency, with help from Hal Drakesmith, a professor of iron biology at Oxford University, and advice from Dr Sue Pavord, a consultant haematologist at Oxford university hospitals and associate senior lecturer in clinical medicine at St Edmund Hall.

US defence secretary Pete Hegseth’s plan to livestream the execution of Nidal Malik Hasan has incurred condemnation from human rights groups and politicians on all sides. But according to Coltan Scrivner, an author and psychologist at Arizona State University and expert on morbid curiosity, people are still likely to watch in large numbers. He explains why we are drawn to dark and disturbing content, and Madeleine Finlay tells Ian Sample how consuming this kind of material can harm observers’ mental health

Quarantine measures have been in place in several hospitals in eastern Russia since a 28-year-old laboratory worker, Darya Shipilova, died after falling ill at work following a reported accident at a plague research centre in Siberia. Russia’s health watchdog has said she died of ‘pneumonia of unknown aetiology’, but there is speculation about a possible plague infection. Lucy Hough speaks to Science Weekly co-host Madeleine Finlay

Each year the Guardian runs a competition to find the invertebrate of the year. To find out more about the 2026 nominees, science editor Ian Sample hears from climate reporter Petra Stock, environment reporter Oliver Milman and Science Weekly co-host Madeleine Finlay. They each nominate an incredible invertebrate that you might never have heard of, and argue why their choice should come top. Vote for your favourite now and the winner will be unveiled on 17 August

Alongside the oil and gas stranded in the strait of Hormuz is another commodity vital to today’s economy: helium. It is a critical element in all kinds of areas from MRI machines to the Large Hadron Collider, and even deep-sea diving. It is also integral to the AI boom. And this isn’t the first time its fragile global supply chain has been threatened. So why is helium so useful, and what will happen if the shortage continues? Ian Sample hears from co-host Madeleine Finlay, and from Sophia Hayes, professor of chemistry at Washington University in St. Louis

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