Think of a shark and you'll probably conjure up images of Jaws, but it turns out their skin is also covered in tiny teeth. Hannah and Dara investigate the incredible properties of these so-called dermal denticles, to find out whether they could be replicated at a nanoscale to increase vehicle speeds. They learn that while sharks might look like they have beautifully sleek surfaces, up close their skin is covered in something extremely rough and textured, a property that helps them swim up to 12 percent faster. And it's already inspiring airlines to design ultra-thin films that can reduce drag and increase efficiency. Contributors Dr Jess Wade Professor Manish Tiwari Producer: Marijke Peters Executive Producer: Sasha Feachem A BBC Studios Audio Production

Why do we giggle, snort, and bust a gut laughing? Is it just humans being weird, does it serve some higher function or do other animals crack up too? And, okay, Dara is a comedian, but has he ever really made anyone laugh, like properly? With help from Professor Greg Bryant and Professor Sophie Scott, they dive into the science of LOLs, exploring how laughter bonds us, eases stress, and even spices up flirting. They uncover the difference between genuine belly laughs and those polite chuckles that pepper everyday interactions. Contributors: Sophie Scott - Professor of Cognitive Neuroscience at UCL Greg Bryant - Professor of Communication at UCLA Betty La - Professor or Communication, Northern Illinois University Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

Ever wondered why some people are mosquito magnets and other people barely get bitten? Hannah and Dara grapple with the question of whether these insects are evil or genius, discovering how they’re experts at finding blood when they’re hungry, even using a specially designed syringe to suck it out. But when Professor Leslie Vosshall tells them some people are more than 100 times likely to be attacked than others, the pair start wondering which one of them is more attractive? So they put the science to the test, and reluctantly agree to send their stinky socks to Professor Sarah Reece. She reveals that one of them smells extra special to these annoying little animals, possibly because of their cheesy feet. But can you guess who? Contributors: Professor Sarah Reece Professor Leslie Vosshall Professor John Pickett Producer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production

The team test the theory that you can use the weather to predict pain, separating science fact from fiction. It's an area with a huge amount of conflicting research, but one man who has investigated this is Professor Will Dixon, who explains that low pressure could be causing people's ts to ache more. Dara and Hannah are intrigued to hear our genes may also be responding to changes in temperature and hear how we might be pre-programmed to produce more inflammation during wintertime to fight off bugs - which has the unfortunate side effect of making other some conditions worse. But don't despair! The pair find out 21 degrees is the optimum temperature for health and wellbeing - a perfect English summer day. Contributors: Dr Chris Wallace Professor Will Dixon Professor Trevor Professor Trevor Harley Producer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production

From mouldy bread to athlete’s foot, fungi don’t exactly scream “home improvement.” But what if this misunderstood kingdom is the secret to the sustainable materials of the future? Listener Alexis - definitely not a gnome - wants to know how much of our homes we could build with fungi. Professor Katie Field describes how the mushroom is the just tip of the iceberg - it’s the network of thread-like filaments called mycelium where fungi really do their best work. Architect Phil Ayers explains how fungi, like yeast in bread, can bind waste products into firm, MDF-like blocks. And while we’re not constructing skyscrapers with mushrooms just yet, it turns out fungi-based materials are already making waves in interior design. Think sound-absorbing wall s or insulation that’s both eco-friendly and chic. And here’s a cool one: mushroom leather! Using discarded stalks from mushroom farms, one company is crafting strong, flexible material for trainers, handbags, and even car dashboards. Move over, cows - mushrooms are pushing their way up. Oh, and NASA? They’re dreaming big with fungi too - to grow habitats in space. From mould...to the moon! Contributors: Katie Field - Professor of Plant-Soil Processes at the University of Sheffield Phil Ayres - Professor of Biohybrid Architecture at the Royal Danish Academy Patrick Baptista Pinto - co-founder of Really Clever Maurizio Montalti - Co-founder and Chief Mycelium Officer of SQIM / MOGU Lynn Rothschild - Senior Research Scientist at NASA Ames research centre Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

What happens in your brain when Cupid’s arrow strikes? As a teenager, Alison developed an intense crush on George Harrison from the Beatles. But, she wants to know, why do we develop these feelings for pop stars we’ve never actually met? And what potent swirl of neurochemistry drives those fierce emotions? With neuroscientist Dr. Dean Burnett and evolutionary anthropologist Dr. Anna Machin as their guides, Hannah and Dara investigate everything from the brain’s chemical fireworks during a crush to the evolutionary perks of love and bonding. Along the way, they dissect teenage infatuations, lifelong love affairs with football teams, and why love can feel as addictive as heroin. There’s even a guest appearance from two cute rodents: the monogamous prairie voles and their more, shall we say, commitment-phobic cousins, the montane voles, who gave us early clues about the role of the ‘cuddle’ hormone oxytocin. Whether you're a hopeless romantic or a hard-nosed skeptic, prepare to fall head over heels for the science of love. Contributors: Dr Anna Machin - evolutionary anthropologist and author of Why We Love Dr Dean Burnett - honorary research fellow at Cardiff Psychology School, author of The Idiot Brain and The Happy Brain. Carmine Pariante - Professor of Biological Psychiatry at King’s College London Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

Hannah and Dara tackle a disarmingly simple question: is anything in the universe truly invisible? After ruling out mysterious Nordic spirits and ‘Dara’s ire’, our curious duo start to track down the invisible waves all around them. Including, it turns out, some which are emanating from their VERY OWN FACES! An infrared camera reveals Hannah’s nose as a particular hotspot. Turning their gaze to bigger things, they wonder: what does our own galaxy look like when viewed in this invisible spectrum? Infrared reveals vast loops and whorls of dust and gas - gigantic structures otherwise totally hidden. But there are even cooler surprises. Ever wondered what an X-ray of the universe looks like? Turns out it’s a sparkly map of white-hot black holes! Back on earth, the discussion turns to ways of making objects disappear by bending light in tricksy ways. But why is the fancy science of ‘metamaterials’ still struggling to make a proper invisibility cloak? Sorry, Harry Potter fans. In the end, our physicists reveal a universe bursting with even more elusive, even more mysterious stuff: dark matter and dark energy. Prepare to see the unseen in a whole new light! Contributors: Matthew Bothwell - the Public Astronomer at the University of Cambridge and author of The Invisible Universe Andrew Pontzen - Professor of Physics at Durham University Mitch Kenney - Assistant Professor in metamaterials at the University of Nottingham Producer: Ilan Goodman Executive Producer: Sasha Feachem A BBC Studios Audio Production

For any of you who have ever told a porkie pie, don't worry, this week we hear why we all do it... and discover that deception is actually good for social bonding. From the red squirrels who cry wolf to scare off the competition, to kids who look you in the eye as they tell bare faced lies, this is a behaviour that occurs across all species. And one man who's particularly good at it is Traitors contestant Paul Gorton who reveals he felt absolutely no guilt about his tv trickery. But it seems that while we're masters at telling tall stories, we're terrible at detecting them, because we've all been focusing on completely the wrong cues. Contributors: Paul Gorton Professor Richard Wiseman Professor Sophie van der Zee Producer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production

“Diamonds are nonsense!” Hannah boldly proclaimed in a previous episode. But listener Guy is a diamond enthusiast, and he and his diamond-loving pals were NOT OKAY WITH THIS. He demanded we re-open the case, and here we are... SO in this glittering showdown, Dara is on a quest to flip Hannah’s perspective from “meh” to “marvelous.” And for Hannah, some uncomfortable facts soon emerge. It turns out that diamonds are much more than just overpriced bling. They're the secret ingredient in all sorts of high-tech gadgets with a whole arsenal of little-known superpowers. Enter electrochemist Julie Maherson, who blows Hannah’s mind by showing how diamonds can slice through ice like butter, thanks to their unmatched ability to conduct heat. Not impressed yet? Physicist Mark Newton makes a diamond glow in the dark, using nothing but his phone flashlight. And that’s just to start! These ultra-robust gems can scrub nasty chemicals from water, serve as supercharged electrodes, and even reveal deep-earth secrets locked away for billions of years. By the end of this episode, will Hannah finally it diamonds are forever cool? Contributors: Charlie Bexfield - Gemmologist and diamond specialist Julie Maherson - Professor of Chemistry at the University of Warwick Mark Newton - Professor of Physics at the University of Warwick Grahame Pearson - Professor of Earth Sciences from the University of Alberta Producer: Ilan Goodman Executive Producer: Sasha Feachem A BBC Studios Audio Production

Hannah Fry and Dara Ó Briain return to tackle listener's questions with the power of science!

Dara O Briain and Isy Suttie meet special guest experts to help them unravel some seriously surprising tales.

The buzz of a fly hovering just above your head has got to be one of the most irritating sounds around, but this week we try to work out just how fast they could be flying. Could a claim horseflies reach speeds of up to 90 mph possibly be true, and Dara wants to know if this is what makes them so difficult to swat? Entomologist Erica McAlister is better known as the ‘fly lady’ and speaks up in defence of these tiny creatures, explaining there are 7,000 known species in the UK alone. Which makes it all the more shocking there are several that don’t have wings. For Professor Graham Taylor the question of speed comes down to a simple calculation, and the team try to work out whether a horsefly beats its wings fast enough relative to its size to travel so rapidly. He explains horseflies aren't clever, but scientists are interested in their simple brains and are studying them to use as models for drones and mini robots. Contributors: Dr Erica McAlister, Natural History Museum Professor Graham Taylor, Oxford University Producer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production

Anyone who has ever done a long car journey with kids will be familiar with the idea of being bored to death – but can this feeling really be fatal? Hannah and Dara hear about a club where count roundabouts and collect milk bottle tops, but boredom expert Wijnand van Tilburg explains these dull-sounding hobbies might actually have mental health benefits. He explains that science and comedy are stereotypically both seen as exciting subjects but warns them their chat about Venn diagrams might tip the balance the other way. Mind-wandering specialist Mike Esterman reveals why we're rubbish at staying on task when there are more rewarding things to do, and sets the pair a challenge to play a computer game that distracts them with pictures of cute babies and fluffy animals. Contributors: Dr Wijnand van Tilburg: University of Essex Dr Mike Esterman: Boston Attention and Learning Lab Producer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production

When you die, would you want to be frozen so that one day you might be brought back to life? Listener Elspeth wants to know if that’s even possible. So Hannah and Dara embark on a quest to explore the chiling science of ‘cryobiology’: preserving living things at really low temperatures. It turns out there are already thousands of people alive who were once suspended in antifreeze and stored in liquid nitrogen - when they were just a small clump of cells! There’s even a frog which can turn into a ‘frogsicle’ for months on end. But re-animating full size humans is a challenge no one has solved…yet. Will some miraculous nanotechnology of a distant future solve the problem? Contributors: Professor João Pedro de Magalhães: University of Birmingham Hayley Campbell: Author and broadcaster Professor Joyce Harper: UCL Dr Hanane Hadj-Moussa: The Babraham Institute, Cambridge Garrett Smyth: Cryonics UK Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

Wake up! It’s time for a dreamy new episode of Curious Cases all about the science of sleepwalking. Listener Abigail has done some strange things in her sleep, from taking all the pictures off the wall, to searching for Turkish language courses. And she wants to know: WHY IS THIS HAPPENING? It turns out Abigail is not alone. Hannah and Dara hear weird and wonderful stories of extreme sleepwalkers - from the lady who went on midnight motorbike excursions, to the artist who does all his best work while asleep. They delve into the neuroscience to find out how you can remain in deep sleep while walking, talking or even peeing in your mum's shopping basket. They learn about some cutting edge research where the participants were sleep deprived and then half-woken with scary sounds, and they zero in on the key triggers, from a boozy night out to a squeaky bed. Contributors Professor Russell Foster: University of Oxford. Professor Guy Leschziner: King’s College London and Guys’ and St Thomas’ hospital Lee Hadwin: the sleep artist Professor sca Siclari: The Netherlands Institute for Neuroscience Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

Fruit-powered batteries are the ultimate school science experiment, but they’re normally used to power a pocket calculator. This week’s listener wants to know if they could do more, and sends the team on a quest to discover whether they could used to send a rocket into space? Professor Saiful Islam is the Guinness World Record holder for the highest voltage from a fruit-based battery, but disappoints the team when he reveals they produce very little power. He used 3,000 of them and only managed a measly 2 Watts. Given that spaceships are famously difficult to get off the ground, it seems a lemon battery might just fail the acid test. Author Randall Munroe is undeterred and suggests alternative ways to get energy from citrus, including burying them to make oil. Then the team discuss the pros and cons of switching to a lemon-based diet. For battery expert Paul Shearing, all this raises a serious question, about how we will power the planes of the future. He suggests solar power could play a part in short-haul flights and discusses some of the exciting battery materials being tested today. Contributors: Randall Munroe, author Professor Paul Shearing, Oxford University Professor Saiful Islam, Oxford University Producer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production

Are you more of a rhino or a kitten? More like a tortoise or a hare? Listener Ivy wants to know what makes a good athlete and so Hannah and Dara tackle the science of sport. Our curious duo get to grips with the rigours of training tailored for endurance events vs those based on more explosive bursts of activity. They consider the contribution of genetics, fast vs slow twitch muscle fibres, the unique advantage of Michael Phelps's body proportions and whether butterfly really is the most ridiculous stroke in swimming. And after a rigorous scientific analysis, Dara turns out to be ideally suited for…netball. Much to his surprise. Contributors Dr Polly McGuigan: University of Bath Dr Mitch Lomax: University of Portsmouth Professor Alun Williams: Manchester Metropolitan University Dr Josephine Perry: Sports psychologist Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

Listener Vivienne has heard that tardigrades - aka moss piglets - have special powers of survival. Radiation? Drought? Extreme cold? NO PROBLEM. Does that mean they could survive an apocalypse? And could they even help us master space travel!? Hannah and Dara learn how to find these little moss piggies in roof gutters and garden corners. And they're amazed by their capacity to dry out and hunker down for decades before springing back to life. But calamity strikes when it turns out that fine glass tubing - in the form of pipettes - is their natural predator. And worse is to come: our curious duo learn that there may be some tardigrades stuck on the moon, and one researcher has even fired them out of a gun. All in the name of science. But they have survived at least 5 mass extinctions so far. So their chances of surviving the next one are pretty good. As long as pipettes aren't involved. Contributors Dr James Frederick Fleming: Natural History Museum of Norway and the University of Oslo Dr Nadja Møbjerg: University of Copenhagen Dr Thomas Boothby: University of Wyoming Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

If there’s one type of discharge you really want to avoid, it’s lightning, but what happens when it hits you? We hear from lightning survivor Kerry Evans, and discover that the best place to shelter – if you ever find yourself in a similarly charged storm – is in a car, or low to the ground. And why this is never a good time to take a selfie. Dr Dan Mitchard from Cardiff University’s excitingly-named Lightning Lab explains why there's no lightning at the poles, and the presenters lament that polar bears and penguins are missing out. We all know about the gods of lightning, but the mysticism doesn't stop there. Above cloud level there are many other types of unusually-named phenomena, reaching to the edge of space, including sprites, trolls and even pixies. And Professor Karen Aplin reveals that lightning has even been discovered on other planets, in a science story that could affect our plans to colonise Mars. Contributors: Dr Daniel Mitchard, Lightning Laboratory, Cardiff University Professor Karen Aplin, University of Bristol Producer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production

11 year old Esther visualises days of the week in a kind of 3D structure. It’s something called ‘synaesthesia’ and she wants to know why it happens - and why other people don’t experience things the way she does. Hannah Fry and Dara Ó Briain explore the vibrant and varied ways different people experience the world, from the man who tastes individual words - including all the stops of the tube - to the composer who sees music in shapes and colours. And along the way, they figure out why Mozart is white wine while Beethoven is red. Contributors: Professor Julia Simner: Professor of Psychology,University of Sussex Professor Jamie Ward: Professor of Cognitive Neuroscience, University of Sussex James Wannerton, President of UK Synaesthesia Association CoriAnder: electronic music producer Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production