How old are we really? What a test can tell us about our biological age

For a long time the appendix was considered disposable. After all, millions of people have theirs removed each year and go on to live healthy lives. But as Heather F Smith, a professor of anatomy at Midwestern University tells Ian Sample, researchers are increasingly understanding what this small worm-shaped organ may be bringing to the table in terms of our health. Smith explains how the appendix is linked to both our immune system development and gut health, and why she thinks an increasing interest in the microbiome may bring it to greater prominence. Help support our independent journalism at theguardian.com/sciencepod

Science correspondent Hannah Devlin joins Ian Sample to discuss three intriguing science stories from the week, from a global study that puts the UK third from bottom when it comes to flourishing, to a man who intentionally suffered more than 200 snake bites in the quest to find a universal antivenom and a breakthrough in the quest to understand the contents of the charred Herculaneum scrolls buried when Mount Vesuvius erupted. Help support our independent journalism at theguardian.com/sciencepod

Direct to consumer tests that claim to tell us our biological – as opposed to chronological – age are getting a lot of attention, but what can they really tell us about our health? Science editor Ian Sample talks to Dr Brian H Chen, an epidemiologist at the California Pacific Medical Center Research Institute, who has conducted research into a variety of these tests called epigenetic clocks. He explains what exactly they are measuring and whether, once we have the results, there are any evidence-based strategies we can adopt to lower our biological age. Help support our independent journalism at theguardian.com/sciencepod

Authorities are still trying to understand what triggered the massive power outage that left the majority of the Iberian Peninsula without electricity on Monday. To understand what might have been at play, and whether there’s any truth to claims that renewable energy sources were to blame, Ian Sample hears from Guardian energy correspondent Jillian Ambrose. And Guardian European community affairs correspondent Ashifa Kassam explains what it was like to experience the blackout and how people reacted. Help support our independent journalism at theguardian.com/sciencepod

Just Stop Oil, the climate activism group behind motorway blockades, petrol station disruption and tomato soup attacks on major artworks, has disbanded after staging a final action in London this weekend. To find out why the group has decided to hang up the famous orange high-vis, Madeleine Finlay hears from our environment correspondent Damien Gayle who has been covering Just Stop Oil since its inception. He explains how policy wins and policing crackdowns combined to bring the movement to a close, and what the future of climate activism could look like in its wake. Help support our independent journalism at theguardian.com/sciencepod

Madeleine Finlay and Ian Sample discuss three intriguing science stories from the week. From a hint at alien life on a distant planet to a clue in the search for answers over why colon cancer rates are rising in the under 50s, and news from scientists who claim to have found a colour no one has seen before. Help support our independent journalism at theguardian.com/sciencepod

The American biotech company Colossal Biosciences recently made headlines around the world with claims it had resurrected the dire wolf, an animal that went extinct at the end of the last ice age. But does what the company has done amount to ‘de-extinction’ or should we instead think of these pups as genetically modified versions of the grey wolves that exist today? Science correspondent Nicola Davis tells Madeleine Finlay about the process that created these wolves, how other companies are joining the effort to use genetic modification in conservation, and why some experts have serious ethical questions about bringing back species whose habitats no longer exist. Help support our independent journalism at theguardian.com/sciencepod

As a measles outbreak expands across the US, comments by health secretary Robert F Kennedy Jr have come under scrutiny. Kennedy has said that the best way to prevent measles is to get vaccinated – but he has also caused alarm among paediatricians, vaccine experts and lawmakers by promoting vitamin A and nutrition as treatments for measles and questioning the safety testing of the MMR vaccine. He also recently announced a US-led scientific effort to establish the cause of what he terms the ‘autism epidemic’, with some experts concerned that this study will support the widely discredited association between autism and vaccines. US health reporter Jessica Glenza tells Ian Sample, the Guardian’s science editor, how these mixed messages are already impacting scientific research.. Help support our independent journalism at theguardian.com/sciencepod

Robin McKie reflects on his 40 years as science editor for the Observer and tells Madeleine Finlay about the game-changing discoveries and scientific controversies that he’s reported on during that time. He describes how the discovery of the structure of DNA revolutionised science, what he learned about misinformation from the HIV/AIDS pandemic and why cold fusion and the millennium bug failed to live up to their hype.. Help support our independent journalism at theguardian.com/sciencepod

Switzerland is leading the world in purifying its water of micropollutants, a concoction of chemicals often found in bodies of water that look crystal clear. They include common medicines like antidepressants and antihistamines, but have unknown and potentially damaging consequences for human and ecosystem health. In the second of a two-part series, Phoebe Weston travels to Geneva to find out how the country has transformed its rivers from sewage-filled health hazards to pristine swimming spots. She tells Madeleine Finlay how a public health disaster in the 1960s spurred the government to act, and what the UK could learn from the Swiss about taking care of a precious national asset.. Help support our independent journalism at theguardian.com/sciencepod