In this Christmas episode of The Infinite Monkey Cage, Brian Cox and Robin Ince head to the North Pole to explore the dazzling science behind the northern lights, the extreme adaptations that help animals - and even Santa Claus - survive the Arctic cold, and how the Earth’s magnetic field might just guide him home. Joining the monkeys are comedian Russell Kane, Arctic explorer Felicity Aston and Polar biologist Lloyd Peck, as they brave the chill to uncover the wonders of one of Earth’s most remote and magical frontiers.

Series Producer: Mel Brown

In perhaps the monkiest Infinite Monkey Cage episode there’s ever been, Brian Cox and Robin Ince attempt to uncover the secrets of love, lust and friendship in primates. Swinging by to offer a hand (or tail) are evolutionary psychologist Robin Dunbar, anthropologist Jo Setchell, and comedian Dave Gorman.

Together the panel explores Dunbar’s number in monkeys – the idea that the number of friendships an individual can maintain correlates with brain size – with the very creator of the theory! They ask whether monkeys feel love the way we do, why some species remain strictly monogamous but others don’t, and what we could learn about ourselves through studying them. Robin goes bananas for bonobo fashion, while Dave couldn’t give a monkey’s about finding an aftershave to complement his natural smell.

Series Producer: Mel Brown

Robin Ince and Brian Cox look up to the heavens as they try to ‘de-mistify’ the foggy science of clouds. They’re joined by Cloud Appreciation Society founder Gavin Pretor-Pinney, climate scientist Amanda Maycock, and former weather presenter and drummer Owain Wyn Evans, for a whirlwind tour of our too often-overlooked aerial realm.

The panel explores how clouds form, why they take such extraordinary shapes, and how satellites and weather balloons help us keep track of them. They discover why low clouds cool the planet but high clouds warm it and why a cloud that weighs as much as a jumbo jet manages to stay up in the sky. From the physics of a crisp packet balancing on a cumulonimbus to the shimmering beauty of noctilucent clouds, tune in for this cirrus-ly fascinating episode.

Series Producer: Mel Brown

Robin Ince and Brian Cox get all fired up, overcome their natural repulsion and come together for this stellar episode on nuclear fusion. They’re joined by plasma physicist Yasmin Andrew, fusion scientist Howard Wilson and comedian Ria Lina to uncover the secrets of star-making here on our planet.

Together the panel discovers how the sun fuses atoms to release energy and why misbehaving, jiggling plasma makes this tricky to recreate on Earth. They explore the competing technological approaches — from giant magnets to the world’s biggest lasers — and find out that the hottest place in the solar system is, in fact, in Oxfordshire. Finally, they ask whether fusion could really provide an unlimited source of clean energy, or whether the technology will forever be “just 20 years away”.

Producer: Melanie Brown

Fishing rods at the ready, Brian Cox and Robin Ince attempt to reel in a creature that has baffled scientists since Aristotle: the eel. Wriggling in to help them uncover the mysteries of one of nature’s slimiest subjects are marine scientists David Righton and Caroline Durif, and comedian Lucy Porter.

How do eels navigate such vast distances so deep under water? Why has no one ever seen them reproduce? And WHY would anyone eat them jellied with pie and mash?! The panel discovers that Spanish eels are always late and that eels from all different countries are thought to meet up somewhere in the Atlantic Ocean for a huge annual orgy.

Producer: Melanie Brown

Robin Ince and Brian Cox wind up at the Royal Observatory in Greenwich – arguably the centre of time – to uncoil the mysteries of what time is and how on Earth (…and on moon) we keep track of it. Taking the time to join them are comedian Marcus Brigstocke, curator of the Royal Observatory Louise Devoy, and Head of the National Timing Centre Leon Lobo.

From ancient Egyptian knuckle counting to sun dials, quartz oscillators and atomic clocks, the panel turns back time to discover how we measured and kept it throughout history. Together, they dial into why Greenwich has become such an important place for time and how time is synchronised and sold across the globe. They explore the flaws and future of accurate astronomical and atomic timekeeping, and Marcus blames the ‘leap second’ for his fry-up failures.

Producer: Olivia Jani

For once, Brian Cox and Robin Ince are on the same wavelength – with thinking caps firmly on, they plug into the science of brain-computer interfaces. Helping them decode the tech are neuroscientist Luke Bashford, biomedical engineer Anne Vanhoestenberghe, and comedian Phil Wang.

Together the panel switches on to the possibilities of using implanted and wearable devices to restore movement, speech, sight… or even to decode thoughts themselves. From the ethics of cognitive enhancement to the future of mind-reading and immersive gaming, strap in for this electrifyingly thought-provoking episode.

Producer: Melanie Brown

What is light? How has it shaped our understanding of the universe, our biology, and even our culture?

Series Producer: Melanie Brown

BBC Studios Audio Production

What really separates a moth from a butterfly? Is it just a matter of day and night, or is there more to this fluttering feud than meets the eye?

Producer: Olivia Jani

BBC Studios Audio Production

Brian Cox and Robin Ince dig deep into the strata of an imagined human history to unearth the curious concept of technofossils. Joined by paleobiologist Sarah Gabbott, material scientist Mark Miodownik and comedian and tech enthusiast Aurie Styla the panel unearth how the everyday objects that we throw away today compare to fossils of the past.

Series Producer: Melanie Brown

BBC Studios Audio Production