Science Weekly

Science correspondent Nicola Davis investigates the strange story of Tam O’Braan and his attempts to grow tea in Scotland. In episode one of this mini-series first broadcast in October 2025, Nicola looks back on her first meeting with O’Braan while working on a feature about tea plantations in the UK. He was selling his award-winning Scottish-grown tea to some of the UK’s finest hotels, but something didn’t quite add up. And Nicola wasn’t the only person taking an interest in his story. Help support our independent journalism at theguardian.com/sciencepod

The first person has been treated with a highly anticipated new gene therapy that aims to turn back the clock on ageing cells. The trial is aimed at retinal cells, with the hope that encouraging them to behave as if they were young again could improve sight in the affected patients. If it proves to be safe, it could open the door to a whole raft of therapies based on the emerging field of cellular rejuvenation. To understand more about this cutting edge research, Madeleine Finlay hears from science editor Ian Sample and from Paul Knoepfler, professor of cell biology and human anatomy at the university of California, Davis.. Help support our independent journalism at theguardian.com/sciencepod

Scientists often talk about the importance of flora and fauna to the health of our planet, but Dr Toby Kiers, an evolutionary biologist and founder of the Society for the Protection of Underground Networks, wants us to consider another force: fungi. Her work charting the planet’s vital underground systems has earned her numerous awards, including a MacArthur fellowship and a Tyler Prize for Environmental Achievement (sometimes called the ‘green’ Nobel). She tells Ian Sample about her work mapping fungal networks on the remote Palmyra Atoll in the Pacific Ocean, and what the research reveals about fungi’s often invisible role. Help support our independent journalism at theguardian.com/sciencepod

Men’s average testosterone levels have halved over the past 50 years, according to scientists who say society is facing a male fertility crisis. Rising levels of obesity and diabetes are expected to play a part, but the team behind the work suggest that environmental factors such as endocrine-disrupting chemicals – which can be found in various household items – and global heating could also be factors in the apparent striking decline. Ian Sample speaks to science correspondent Hannah Devlin to find out how the work has been received and what the researchers want to see happen in response to their finding. Help support our independent journalism at theguardian.com/sciencepod

In the last 50 years, Britain has lost an astonishing 73 million wild birds from its landscape, according to the British Trust for Ornithology. Habitat loss, pesticides, disease, cats and the climate crisis mean there are fewer birds than ever before. For children and young people it can be difficult to appreciate the scale of the loss due to a psychological phenomenon called ‘shifting baseline syndrome’, where each generation inherits a degraded version of the environment, and therefore doesn’t notice the overall decline. But Gen Z are bucking the trend. Thanks to social media and the Merlin Bird ID app, birding has become cool. To find out what we’re missing from the dawn chorus, and why young people are embracing birdwatching, Madeleine Finlay hears from the writer Robert Macfarlane and from Jess Painter, a member of the RSPB’s youth council. Help support our independent journalism at theguardian.com/sciencepod

Researchers claim they are closer to creating life from nothing after building tiny, quivering blobs that use lab-made DNA to feed, grow and multiply in a dish. To find out how significant this step is, and where scientists hope it will lead, Madeleine Finlay hears from co-host Ian Sample and from Kate Adamala, professor of genetics at the University of Minnesota. Help support our independent journalism at theguardian.com/sciencepod

The Lincoln Memorial reflecting pool in Washington DC has hardly been out of the news since April when President Trump vowed to have it renovated, and painted ‘American flag blue’ by 4 July. Despite the pool being stripped, cleaned, coated and refilled, within days the algae that has plagued it for decades was back. To find out why these blooms happen, what makes them so difficult to tackle and what Trump could try next, Ian Sample hears from co-host Madeleine Finlay, and from Dr Linda May, a freshwater ecologist at the UK Centre for Ecology & Hydrology.. Help support our independent journalism at theguardian.com/sciencepod

How much do our genes determine about our lives, and could they influence traits like risk-taking, antisocial behaviour or even violence? Ian Sample talks to Kathryn Paige Harden, a behavioural geneticist and professor of psychology at the University of Texas at Austin who studies how genetic factors shape human behaviour. In her book Original Sin she explores how nature and nurture combine to influence our likelihood of committing crimes, and asks whether the ‘cause’ of our actions matters for how we think about culpability. Help support our independent journalism at theguardian.com/sciencepod

Met Office forecasters have issued a rare red weather warning for England, with temperatures potentially reaching 40C (104F) in some places. Europe is also dealing with a debilitating heatwave, with schools closed, trains cancelled and France even restricting the consumption of alcohol outdoors to take pressure off the emergency services. The high temperatures coincide with the coming El Niño, which some scientists have nicknamed Godzilla for its predicted strength. To find out whether the two are linked, Ian Sample hears from our Europe climate correspondent, Ajit Niranjan. He explains why it’s so hot, why we could be in for even worse and how we can keep as cool as possible. Help support our independent journalism at theguardian.com/sciencepod

Sea ice is melting fast and worsening the climate crisis. But what if there were a way to thicken it again? Madeleine Finlay is joined by environment editor Damian Carrington to discuss a bold attempt to refreeze the Arctic which is showing early signs of success. He visited the project to find out how it will work, how much it will cost and whether it really has potential to improve the fate of the Arctic’s ice. Help support our independent journalism at theguardian.com/sciencepod