It is now less than 100 days until Cop15, the UN convention on biological diversity. At these talks, which are taking place in Montreal, Canada in December, governments from around the world will come together to agree targets aimed at halting the destruction of the natural world and protecting biodiversity. With the Earth experiencing the largest loss of life since the extinction of the dinosaurs, what is decided at this meeting could shape the future of the planet and humanity. Madeleine Finlay speaks to biodiversity reporter Phoebe Weston about how negotiations have been going so far, and what’s next on the road to Cop15. Help support our independent journalism at theguardian.com/sciencepod

Holidaymakers heading to British beaches and rivers were faced with a very unpleasant problem this summer – raw sewage. The sewage system usually carries rainwater and dirty wastewater from bathrooms and kitchens to treatment works but during ‘exceptional events’ such as heavy rainfall, when it is likely to be overwhelmed, raw sewage can be diverted and discharged into rivers and seas. Available data shows that in 2021, water companies released untreated sewage into waterways for 2.7m hours – with many discharge pipe monitors not working or left uninstalled. Madeleine Finlay speaks to reporter Helena Horton about why this is happening, and the damage it is doing to the environment, our health, and the UK’s seafood industry. Help support our independent journalism at theguardian.com/sciencepod

Many teenagers will receive their GCSE results today. These exams can have a significant impact on what they do next, so it can be a stressful time for students, their teachers and parents. Over the past decade, reported mental health problems among teenagers have been on the rise. A recent survey by the NHS statistics agency found rates of probable mental disorders in six- to 16-year-olds reached one in six in 2021. Madeleine Finlay speaks to the academic psychologist Dr Lucy Foulkes about what could be behind this crisis, how schools are trying to tackle it, and how we can help teenagers with their mental wellbeing. Help support our independent journalism at theguardian.com/sciencepod

About 325 million years ago, when Britain sat near the equator as part of the supercontinent Pangaea, two populations of a small, scaly, swamp-dwelling creature separated from each other. One of these lineages, over millions and millions of years, evolved into mammals. Our ancestors shared the planet with dinosaurs, survived an asteroid and made it through an ice age. This fascinating history is documented in The Rise and Reign of the Mammals, a new book by the palaeontologist Prof Steve Brusatte. The Guardian science correspondent Nicola Davis talks to Madeleine Finlay about her visit with Brusatte and what she learned about the strange mammals that once walked the Earth. What might their past reveal about their future in a rapidly changing world?. Help support our independent journalism at theguardian.com/sciencepod

‘In this world nothing can be said to be certain, except death and taxes.’ While Benjamin Franklin’s quote remains true for most, the same might not be said for some of the world’s billionaires. And their efforts to extend life are under way too. Most recently, a Silicon Valley startup called Altos Labs signed up a dream team of scientists, including numerous Nobel laureates, with an aim to rejuvenate human cells. In this episode from February 2022, Ian Sample speaks to Prof Janet Lord about the science of ageing, extending our health as well as our lifespans, and how old we could actually go. Help support our independent journalism at theguardian.com/sciencepod

They may be one of the world’s favourite supplements but, according to a study from earlier this year, more than one in 10 fish oil capsules are rancid. Most of the oil comes from Peruvian anchovetas, a type of anchovy that is also used to feed pigs, poultry and farmed fish. And despite catching more than 4m tonnes a year of anchovetas to cater to the global demand, large industry players want to scale this up even further. In this episode from January 2022, Madeleine Finlay speaks to environment journalist Richa Syal about why so many fish oil pills are rancid, and hears from journalist Dan Collyns in Chimbote, Peru, about how the industry is affecting the local environment and its residents. Help support our independent journalism at theguardian.com/sciencepod

Could the food we eat and the air we breathe be damaging our immune systems? The number of people with autoimmune diseases, from rheumatoid arthritis to type 1 diabetes, began to increase around 40 years ago in the west. Now, some are also emerging in countries that had never seen the diseases before. In this episode from January 2022, Ian Sample speaks to the genetic scientist and consultant gastroenterologist James Lee about how this points to what western lifestyles might be doing to our health, and how genetics could reveal exactly how our immune systems are malfunctioning. Help support our independent journalism at theguardian.com/sciencepod

In early April this year, the Intergovernmental Panel on Climate Change released a new report giving the world just 30 months to get greenhouse gas emissions falling. Beyond that, we’ll have missed our chance of limiting global heating to 1.5C. As this summer of heatwaves, droughts, wildfires and floods prove, going much above 1.5C will have truly devastating consequences for us and the planet. With the window of opportunity rapidly closing, some scientists feel like writing reports and publishing papers is no longer enough, and are leaving their desks and labs to take action on the streets. In this episode recorded back in April, Madeleine Finlay meets scientists protesting at Shell HQ in London and speaks to the conservationist Dr Charlie Gardner about civil disobedience – and why he thinks it’s the only option left. Help support our independent journalism at theguardian.com/sciencepod

James Lovelock, the creator of the Gaia hypothesis, died last Tuesday on his 103rd birthday. Known as something of a maverick, the scientist and inventor was one of the most influential thinkers of the past century. Our global environment editor, Jonathan Watts, tells Madeleine Finlay about spending time with Lovelock for his forthcoming biography, the impact of the scientist’s ideas and inventions on the modern world, and how his immense influence will continue to be felt in the critical decades ahead. Help support our independent journalism at theguardian.com/sciencepod

For decades, the absolute priority when rescuing victims after traffic accidents has been to minimise movement of the spine. Emergency services go to great lengths to keep the patient still while they are cut free from the wreckage, because a shift of just a millimetre could potentially lead to the person needing to use a wheelchair. Or at least, that’s what firefighters used to think. Now, thanks to new research using simulated accident rescues, that wisdom is starting to change. Anand Jagatia speaks to the Guardian’s science correspondent, Linda Geddes, and emergency medicine consultant Dr Tim Nutbeam about the findings, and what they mean for survivors of motor vehicle collisions.. Help support our independent journalism at theguardian.com/sciencepod