We Didn't Start the Fire

We often associate yawning with being tired or bored - but this week's episode explores whether it could be a clever way to cool down our brains? Hannah and Dara discover humans aren't the only species that yawn. From cats to chimpanzees and even fish, plenty of other vertebrates engage in this ancient behaviour which scientists believe evolved hundreds of millions of years ago. And it doesn't always happen as a spontaneous reflex to feeling tired but can also be triggered by watching other people do it. If you have an everyday mystery for the team to investigate, contact them on [email protected] Contributors: Stephen Jackson - Professor of Cognitive Neuroscience, University of Nottingham

What happens when you give water a really good shake? You might expect splashing, spilling and general aquatic chaos - but under exactly the right conditions, something much stranger can happen... In this episode, Hannah Fry and Dara Ó Briain dive into the world of 'Faraday waves': amazing geometric patterns that, in certain circumstances, will appear on the surface of a vibrating liquid. They discover how the renowned physicist Michael Faraday accidentally discovered this remarkable phenomenon in the 19th Century; debate whether they could ever occur in a swimming pool; and find out what on earth alligators have to do with it. Along the way, the pair encounter eerie ‘square’ seas and learn about new ways satellites are helping us to understand the ocean’s wildest waves! If you have an everyday mystery for the team to investigate, contact them on [email protected]. Contributors: Cédric Beaume - Associate Professor in Applied Mathematics at the University of Leeds Lucy Bricheno - Group Head of Coastal Ocean at Liverpool’s National Oceanography Centre Glynn Holt - Former Professor of Mechanical Engineering at Boston University Producer: Lucy Taylor Executive Producer: Sasha Feachem A BBC Studios Production

Ever wondered how close nature can get to making a human clone? And what happens if identical twin brothers marry identical twin sisters and have babies - how similar are they? Our listener Chris has been pondering this very issue, and his question takes Hannah and Dara down another scientific rabbit hole. Our intrepid duo consider how one fertilised egg can somehow become two babies, why those babies aren’t quite genetic photocopies, and why even identical twins gradually become more different as they grow up. They also find out how studying twins is helping scientists learn lessons about how all of us age - and explore the classic, movie-perpetuated mystery of “twin telepathy”… could there maybe, possibly, be something to it?! There’s also just time to address the tricky issue of cloning. From Dolly the sheep to regenerative medicine, cloning science has paved the way for some serious breakthroughs; but could we ever clone a human? And more to the point, should we? Expect sheep, sci-fi, identical cousins, and a dash of disproven twin mythology, as Curious Cases makes its return! If you have an everyday mystery for the team to investigate, contact them on [email protected]. Contributors: Xand van Tulleken - Doctor, broadcaster and Honorary Associate Professor of Infection and Population Health at University College London Kevin Sinclair - Professor of Developmental Biology and Head of Animal Sciences at the University of Nottingham Claire Steves - Principal Investigator at TwinsUK and Professor of Ageing and Health at King’s College London Chris van Tulleken - Doctor, broadcaster and Professor of Infection and Global Health at University College London Producer: Lucy Taylor Executive Producer: Sasha Feachem A BBC Studios Production

Hannah Fry and Dara Ó Briain return for a new series, and a whole lot of new problems to solve!

One winter morning, listener Jane opened her curtains to find her car roof covered in breathtaking, fern-like frost so intricate it looked like a William Morris print. But how does something as ordinary as ice create patterns so beautifully complex? Hannah and Dara explore this crunchy, slippery, delicately patterned branch of chemistry to uncover the rules and mysteries that govern the extra-ordinary world of ice. Why does ice come in so many shapes and sizes? And does all ice form at 0 degrees Celsius? Is every snowflake truly unique? We have questions a plenty for our eager chemists, who, as all good chemists do, have a few demonstrations up their sleeves to help explain. And we explore nature’s hidden geometry to find why these frost ferns follow the same rules as lightning bolts, river deltas and even human lungs. You can send your everyday mysteries for the team to investigate to: [email protected] Contributors Sarah Hart – Professor Emerita of Mathematics, Birkbeck University of London Christoph Salzmann – Professor of Physical and Materials Chemistry, UCL Dr Thomas Whale – Lecturer, Institute for Climate and Atmospheric Science, University of Leeds Producer: Emily Bird Executive Producer: Sasha Feachem A BBC Studios Production