CrowdScience

Some people fall asleep almost as soon as their head touches the pillow, while for others it can take hours of tossing and turning. CrowdScience listener Assia needs at least 45 minutes to get to sleep: it's always taken her a long time to drift off no matter how tired she is, and nothing seems to make a difference. She asked us to investigate. Presenter Caroline Steel turns to experts to find out what happens in our bodies when we fall asleep, and why it’s more difficult for some than others. Eus van Someren explains how our bodies know when it’s time to get some rest and what can influence the difficulty of getting to sleep from our earliest years. Morten Kringelbach reveals that there may be more stages of sleep than we thought, and Ada Eban-Rothschild tells us why we have something to learn from the birds and the bees about getting a good night’s rest. Caroline has trouble getting to sleep herself, and volunteers to have her sleep monitored in Cardiff University’s sleep lab. And we share some expert tips on falling asleep more easily. Presenter: Caroline Steel Producer: Jo Glanville Editor: Cathy Edwards Studio Manager: Jackie Margerum Production co-ordinators: Jana Holesworth and Josie Hardy With thanks to Professor Milton Mermikides for permission to include his composition ‘Transitions’. (Photo: Caroline Steel takes a nap in Cardiff University’s sleep lab)

According to the United Nations Food and Agriculture Organisation, 800 million people are going to bed hungry every night, but 2 billion people in the world are malnourished. Farmers across the globe produce enough food to feed 10 billion people, yet there are only 7.6 billion of us. We know there is enough food to go around, but filling tummies is only the start – we also need a varied diet. CrowdScience visits Nairobi during GGIAR Science Week, a hub for agricultural scientists. They are meeting to discuss the changes needed to get the right crops into the soil and the right food on the plates of those who need it. Presenters Anand Jagatia and Alex Lathbridge are joined by a live audience and a panel of experts Lindiwe Sibanda, Sieglinde Snapp and Alex Awiti. Together they explore questions from our listeners in Kenya and around the world: whether we can restore natural habitats whilst promoting food security; why human waste isn’t used more commonly as a fertiliser; and what impact empowering women in agriculture will have on our ability to feed the world. Recorded at CGIAR Science Week at the UN headquarters in Nairobi. Image: Drone view of tractor ploughing a field Image Credit: Justin Paget via Getty Images Presenters: Anand Jagatia & Alex Lathbridge Producer: Harrison Lewis Editors: Martin Smith & Cathy Edwards Production Co-ordinators: Ishmael Soriano & Josie Hardy Studio Managers: Gayl Gordon, Andrew Garratt & Sarah Hockley

CrowdScience listener Sid is running late, and he’s turning to science to find an excuse. He and his partner Steffi in Singapore have very different attitudes to timekeeping. They wonder if this is down to their different cultural upbringings, or if they just had very different brains to start with. Presenter Chhavi Sachdev puts her own time perception skills to the test to try to understand how subjective our sense of time can be. And we discover how the language we grow up speaking can influence the way we think about punctuality. Presenter: Chhavi Sachdev Producer: Emily Bird Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Jackie Margerum

What would you discover inside the stomach of a sea lion? CrowdScience listener Robyn found out first-hand when she volunteered at her local museum in Adelaide, Australia. The team dissecting the specimen removed around 30 rocks from the animal’s stomach, and Robyn wants the Crowdscience team to find out how and why they got there. Presenter Anand Jagatia uncovers a whole world of rock-munching creatures, from ostriches to ichthyosaurs. In search of answers we investigate Canadian sea lion research, and rummage through the vaults at the Natural History Museum in Bamberg, Germany. Presented by Anand Jagatia Produced by Emily Bird Image: Australian Sea Lion (Neophoca cinerea), Hopkins Island, South Australia Credit: Stephen Frink via Getty Images

On the banks of the St Lawrence River in Quebec stands a 100-year-old lighthouse. While initially built to help boats navigate one of Canada’s most difficult waterways, the Point-de-Père site now also holds a different responsibility: it is a key reference for measuring sea levels around the entire North America continent. But this is all set to change. With the development of new satellite technology, the tricky task of measuring sea levels is being updated - which could mean mountains around North America get brand new official heights. In this episode we revisit a question from CrowdScience listener Beth, who wondered about the elevation signs she saw scattered along a mountainous road, indicating how high above sea level she was. As sea levels rise, will all the elevation signs need repainting? And how do you measure sea level, anyway? The height of an enormous pile of rock like Ben Nevis, or Mount Everest feels unchangeable. But we measure them relative to the nearest patch of sea, which is where our story becomes complicated. Unlike water in a bath, sea level is not equal around the world. In fact, nothing on earth - not the sea, the shore or the mountains - is stable or constant, so the question of what you measure from and to becomes incredibly tricky. But that hasn’t stopped scientists risking life and fingers to use an ever-evolving array of technologies to find answers. Join host Marnie Chesterton as she dives into the mechanics of the latest sea level technology, and how it could make a big difference to understanding our unpredictable world. Presenter: Marnie Chesterton Producer: Julia Ravey and Marnie Chesterton Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano and Jana Holesworth Studio Manager: Emma Harth (Image: Elevation Sign Post, Rocky Mountain National Park. Credit: Stephanie Beverungen via Getty Images.)

Host Anand Jagatia tackles gravity - a fundamental force of the universe yet also an everyday mystery that has baffled several listeners. Can you outrun it? Or at least use it to get fitter? If it varies, does that mean that you weigh less, depending on where on earth you stand? And if it’s the force of attraction between any objects with mass, are you technically more attractive after eating a massive cake? Professor Claudia de Rham from Imperial College London explains the basics of gravity, while we discover the best place on earth to weight ourselves, with Professor Paddy Regan from Surrey University and NPL Fellow in Nuclear and Radiation Science and Metrology. Anand takes a very fast spin on a special chair to experience extra gravity, thanks to Professor Floris Wuyts from the University of Antwerp, Kings College London and Minister of Science of Asgardia. And finally, we talk to an expert lined up at the other end of a hypothetical hole through the earth: Professor Richard Easther from the University of Auckland, New Zealand. What would happen if we fell straight through the earth? CrowdScience finds gravity a force to be reckoned with. Presenter: Anand Jagatia Producer: Marnie Chesterton Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano and Jana Bennett-Holesworth Studio Manager: Jackie Margerum and Duncan Hannant Photo: Anand Jagatia experiencing extra g-force

Are food allergies higher in the West than the East? UK-based listener Jude wants to know the answer. Her daughter-in-law Min didn’t know anyone with food allergies when she was growing up in South Korea and thinks that they’re not so common there. Host Alex Lathbridge investigates. Along the way, he finds out what makes us sensitive to food allergies and how much that depends on our environment. He volunteers to have an allergy test, learns what triggers food allergies and tries to discover what lies behind their increase around the world. Alex talks to some of the leading experts on food allergies in search for an answer to our listener’s question: Paul Turner breaks down what happens in our bodies when we have an allergic reaction; Jennifer Koplin explains why Australia tops the league table for food allergies and Michael Levin reveals what he found out in his ground-breaking research in South Africa comparing urban and rural populations. We also hear from Hana Ayoob, who grew up in Singapore and the UK, who describes what it’s like to suffer from multiple food allergies and describes the difference in cultural attitudes. Finally, we turn to Sooyoung Lee in South Korea to see if our listeners are right about the difference in rates for food allergies between East and West. Presenter: Alex Lathbridge Producer: Jo Glanville Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Duncan Hannant (Image: Young Asian father with cute little daughter grocery shopping for dairy products in supermarket Credit: d3sign via Getty Images)

CrowdScience listener Alina is in a relationship with a polyamorous partner and is very happy with this arrangement, which got her thinking – why is monogamy so often the norm in human societies? Presenter Caroline Steel goes on an anthropological odyssey to figure out where this drive to find a single partner - and stick with them - comes from. What can science tell us about how human relationships developed, and whether having one or many partners is more 'natural'? Evolutionary biologist Kit Opie of the University of Bristol joins us at London Zoo to help us understand the mating systems of our closest primate relatives. To find out how polygamy developed in some parts of the world we speak to anthropologist Katie Starkweather of the University of Illinois Chicago. And we learn about the chemistry of bonding from Sarah Blumenthal at Emory University, who explains how the brains of prairie voles may give us clue about the neurochemicals which shape human relationships. Presenter: Caroline Steel Producers: Priya Sippy, Ben Motley and Imaan Moin Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Steve Greenwood (Image: Dancing wedding cake figurines Credit: Peter Dazeley via Getty Images)

The wetness of water seems blindingly obvious - but dive into the science and things aren’t so clear. CrowdScience listeners Rachel and Callum were washing their hands one day and it got them thinking about wetness. Why does water feel the way it does? And what makes a liquid wet? To find out, presenter Anand Jagatia takes a closer look at the behaviour of liquids with materials scientist Mark Miodownik, and finds out why they might not be as wet as we think. We learn what’s really behind the sensation of feeling something wet on your skin, with the help of physiologist Davide Filingeri and PhD student Jade Ward. And we turn to a philosopher, Vanessa Seifert, and a chemist, Tim Neudecker, to puzzle out exactly how many water molecules you need before the property of wetness emerges. Presenter: Anand Jagatia Producer: Anand Jagatia Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Bob Nettles and Andrew Garratt (Image: A photo of a droplet falling into a body of water Credit: Flaviu Cernea / 500pxvia Getty Images)

It’s citrus season in the northern hemisphere, and fruit trees are bursting with oranges and lemons. But CrowdScience listener Jonathan wants to know what happened to the tangerines he ate as a child in the 1960s? He remembers a fruit that was juicy, sweet and full of pips, found each Christmas at the bottom of his stocking. Tangerines today, he thinks, just don't compare. Crowdscience tries to track down this elusive fruit. Presenter Anand Jagatia traces the tangerine's origins back to Ancient China, as botanist David Mabberley explains that the name ‘tangerine’ comes from a fruit that made its way from Asia, to Africa and the Moroccan port of Tangier, before arriving in the US in the early 1800s. Professor Tracy Kahn from UC Riverside tells us about the hybridisation process that goes into breeding modern tangerines, but says that while the season for these fruits has been dramatically extended, there’s a cost in terms of diversity and flavour. Who better to help us track down this missing mandarin than a fruit detective? Well, that’s one of pomologist David Karp’s other job titles, and he reveals exactly which cultivar we might be looking for: the Dancy. So where can we find one? Over on Friend’s Ranches in Ojai, California, Emily Ayala shows us two trees planted by her late grandfather, and explains that nothing grown since really matches its unique flavour. So what will listener Jonathan think when we send him a box? Presenter: Anand Jagatia Producer: Marijke Peters Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Jackie Margerum (Image: Citrus oranges grow on tree, Hong Kong Credit: CHUNYIP WONG via Getty Images)

Vermillion red, vibrant orange, golden yellows, even violet – we're enchanted by the colours that make up a stunning sunset or sunrise. CrowdScience listener Paulina, a lighting designer from Chile, often uses the sunsets she sees from her balcony as inspiration for her designs. And during the day and night, the sky can be all sorts of shades of blue. But Paulina wonders why, in the colour palette of the sky, she never sees any green. CrowdScience gazes skywards to investigate. Presenter Caroline Steel travels to the Arctic Circle to meet atmospheric physicist Katie Herlingshaw. Katie explains why we usually see the sky as blue, and what makes it transform into fiery reds and oranges at sunrise and sunset. We also peer into the science of perception, as neuroscientist Bevil Conway tells us what’s going on in our eyes (and brains) to make the colours we see in the sky. But there are some rare occasions when the sky can appear to be green, such as in a rainbow or a green flash at sunset. And then there is the spellbinding green glow of the aurora - the Northern and Southern Lights. We visit the northernmost aurora observatory in the world to try to understand this phenomenon. Are green skies more common than we think? Presenter: Caroline Steel Producer: Hannah Fisher Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Sarah Hockley (Photo: View of sunset in Santiago, Chile. Photo montage courtesy of Paulina Villalobos)

CrowdScience listener Dorit has a problem. She wants the tiles in her new bathroom to be arranged randomly but, no matter what she does, it still looks like they form some kind of pattern. This has got Dorit thinking about randomness – what is it, how do you create it, why do we find it so hard to recognise, and is anything really random at all? And if nothing is truly random, does it mean that everything is theoretically predictable? Tiling your bathroom is a much more existential problem than you might have thought. Never afraid of a question, whether big (is everything pre-determined?) or small (how do I tile my bathroom?), CrowdScience is on the case. Anand Jagatia heads to Switzerland to meet Hugo Duminil-Copin, a mathematician at the University of Geneva who specialises in probability theory. On the top floor of an old bank, Hugo has Anand flipping an imaginary coin in a random order. Hugo explains that randomness is something that cannot be predicted by any means – so why is it so easy for Hugo to guess what Anand’s next move is? Meanwhile, at the National Institutes of Mental Health in Maryland USA, Susan Wardle is a cognitive neuroscientist who researches how the human brain processes visual information. Can neuroscience help Dorit with her tiling problem, and is there a reason why the human brain likes to put random objects into some kind of order? Geneva is also the birthplace of the first Quantum Random Number Generator for smartphones, and CrowdScience has persuaded some of the University of Geneva’s finest quantum physicists to hook a photon detector up to a synthesiser. Thanks to Tiff Brydges and Nicolas Brunner, we can actually hear quantum particles behaving randomly. But is quantum randomness truly random, or just a pattern that we can’t see? And could quantum physics help Dorit tile her bathroom? Presenter: Anand Jagatia Producer: Ben Motley Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Technical producer: Jackie Margerum

Some of our biggest achievements happen in the first years of our lives. Taking our first steps, picking up a complex language from scratch, and forming relationships with some of the most important people we’ll ever meet. But when we try to remember this period of great change, we often draw a blank. After losing his Dad aged four, CrowdScience listener Colin has grappled with this. Why can’t he recall memories of such a monumental figure in his life, yet superficial relationships from his teens remain crystal clear in his mind? Colin takes presenter Marnie Chesterton to visit some of the significant locations of his childhood, places he would have spent many hours with his late father; and he recounts his earliest memories. On this trip down memory lane, Marnie discovers the psychological mechanisms behind our lack of early childhood memories. Sarah Power from the Max Planck Institute for Human Development discusses the evolution of our memory systems, detecting false memories from real ones, and her world-first study exploring how infants form memories in real time. Elaine Reese from the University of Otago digs into the relationship between environment and culture when our earliest experiences solidify into memories. And Tomás Ryan, neuroscientist at Trinity College Dublin, reveals fascinating new insights from animal studies that hint that these memories could still be lurking inside our heads... Presenter: Marnie Chesterton Producer: Julia Ravey Content Editor: Cathy Edwards Production Co-ordinators: Ishmael Soriano & Josie Hardy Technical Producer: Emma Harth (Photo: Marnie Chesterton and CrowdScience listener, Colin, on the swings in Belfast.)

Smartwatches are increasingly popular: around the world many of us use these wearable devices to monitor our performance and improve our fitness. But how reliable is the data they collect, and can they actually make us healthier? CrowdScience listener Caitlin from Malawi is a big fan of her smartwatch. Her husband Fayaz, however, is much more sceptical of its accuracy, and has asked us to investigate. We meet up with them both at the gym, where Caitlin and presenter Caroline Steel put their fitness trackers – and themselves – to the test. We visit public health researchers Dr Cailbhe Doherty and Rory Lambe, who investigate the accuracy of wearable consumer devices, at University College Dublin. Caroline again pushes herself to the limit to see how her smartwatch results measure up to those from gold standard laboratory equipment. But is it crucial for smartwatches to be accurate: if they get us off the couch, is that what makes the difference to our health? Health behaviour expert Dr Ty Ferguson from the University of South Australia has studied this very question. And finally, how does quantifying our every move affect the way we think about ourselves and how we live? Professor Deborah Lupton from UNSW Sydney shares some insights. Presenter: Caroline Steel Producers: Jo Glanville and Sophie Ormiston Editor: Cathy Edwards Technical producer: Sarah Hockley Production co-ordinator: Ishmael Soriano

While watching a feisty cockatoo chase after a hawk, CrowdScience listener Alison saw the hawk catch a thermal and rise effortlessly into the sky. The cockatoo gave chase, but the hawk climbed higher and higher until it became just a tiny speck, barely visible to the naked eye. And that got Alison thinking: just how high can birds go? Are there altitude limits for our feathered friends? Could a cockatoo, a sparrow, or even a duck reach such dizzying heights if they really put their wings to it? Presenter Alex Lathbridge sets out to investigate. Biologist Catherine Ivy reveals that life above the clouds isn’t easy. At high altitudes, the air is thinner, oxygen is scarce, and wings don’t generate as much lift. But some bird species have evolved incredible adaptations to overcome these challenges. Among them: bar-headed geese, renowned for their daring flights over the world’s tallest mountains. Physiologist Lucy Hawkes delves into how these geese defy the odds with their remarkable physiology, revealing the surprising discoveries she made while putting some of them on a treadmill. From super-powered hearts to clever lungs, we uncover the secrets behind nature’s impressive aviators. Presenter: Alex Lathbridge Producers: Ilan Goodman and Jeremy Grange Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Technical producer: Sarah Hockley

Carbon footprints are a measure of how much we each contribute to the greenhouse gases that warm the Earth’s atmosphere. The global average of carbon dioxide emissions is nearly 5 tonnes per person per year, although it can be triple that in certain countries. But one CrowdScience listener in Ghana is wondering about the bigger picture. After all, humans aren’t the only species on this planet. So which other animal has the biggest carbon footprint? CrowdScience presenters Caroline Steel and Marnie Chesterton are on the case, examining and arguing over the animal that deserves the top spot for this title. Caroline, a vegan, points to the cow as the top contender, since the livestock sector produces 14.5% of total greenhouse gas emissions, and cows, whether as meat or dairy animals, are responsible for the majority of that. The team look at initiatives around the world to be more efficient with each animal out there. But maybe it’s time to put another sector in the spotlight? Pets. We love our dogs and cats but do their meat-based diets win them a place on the podium? From most loved to most detested, we look at the role that key pests play in upsetting the carbon budget. Could a small beetle with a large appetite for greenery be an unusual winner, thanks to the trees these pests destroy over their lifetimes? Is the biggest offender a carbon footprint, hoofprint, pawprint, or clawprint? Presenters: Caroline Steel and Marnie Chesterton Producer: Marnie Chesterton Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Technical producers: Sarah Hockley and Donald MacDonald

In the past stout beer has been touted for its supposed health benefits. Is there any truth to those claims - and what happens if you take the alcohol out? CrowdScience listener Aengus pondered these questions down at the pub, after noticing most of his friends were drinking non-alcoholic beers. He wondered how the non-alcoholic stuff is made – what’s taken out and what’s added in – and whether the final product is better for you than the alcoholic version. It’s a question that takes us to Belgium, home to the experimental brewery of a global drinks company which takes the growing market for alcohol-free beer very seriously. David De Schutter, head of research and development, shows host Marnie Chesterton how to take alcohol out of beer without spoiling the flavour. We also find our way to a yeast lab in Leuven, Belgium where Kevin Verstrepen and his team have found another way to make alcohol-free beer with the help of industrious microbes: yeast varieties that brew beer without producing any alcohol in the first place. And how do they compare to the alcoholic versions? We discuss the importance of aromas in our perception of beer’s taste. So should listener Aengus stick to non-alcoholic stout? We speak to scientist Tim Stockwell about the health drawbacks of alcohol, even in moderation. And gut microbiome researcher Cláudia Marques fills us in on her delicious pilot study, which looked at the effects of both non-alcoholic and alcoholic beers on our digestive tract. Along the way, Marnie taste-tests what's on the market, and asks the experts why this particular grocery shelf has become so much bigger and more flavourful in recent years. Presenter: Marnie Chesterton Producer: Sam Baker Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Technical producers: Giles Aspen, Andrew Garratt and Donald MacDonald (Image: Close-up of waitress holding craft beer at bar, Brazil Credit: FG Trade via Getty Images)

When listener Diana fell on a run on her birthday, her first instinct was not to check her bruised hand, but instead to get up as quickly as possible and act as if nothing had happened. She felt embarrassed. Meanwhile, her son Marley loves to watch fail videos that, mostly, show people falling over. So why does falling – something that can cause serious injury – elicit both embarrassment and laughter? In the name of CrowdScience, presenter Caroline Steel trips, stumbles and falls. She spends a morning with clown Sean Kempton who teaches her slapstick skills, including how to do it safely. Psychologist Rowland Miller explains why falling can be embarrassing and shares his theory of why humans have developed this emotion in the first place. Then it’s time for Caroline to try out Diana’s predicament herself. If a BBC presenter falls in a park, will she feel embarrassed? From embarrassment to laughter, psychologist Janet Gibson lists the ingredients of a funny fall, and humour expert Caleb Warren explains how they can get funnier with distance. Then Caroline tries, semi-successfully, to make members of the public laugh. Will clown Sean do a better job? Presenter: Caroline Steel Producer: Florian Bohr Editor: Cathy Edwards Production coordinators: Ishmael Soriano Sound engineers: Bob Nettles, Tim Heffer and Giles Aspen

Did you know that flies fly in rectangles, fish hide by lighting themselves up and the moon is lifting the ground underneath your feet? Anand Jagatia quizzes members of the CrowdScience team on the moments from the past year that had them scratching their heads in amazement. We hear Dr Erica McAlister’s attempts to calculate how many flies have ever existed, and about flies’ mating choreography, courtesy of Prof Jochen Zeil. We learn how to tell a mosquito’s sex thanks to Eggrey Aisha Kambewa and Dr Steve Gowelo. Astronomer Dr Darren Baskill describes tides not of water but of land; Dr Edie Widder paints a vivid picture of a camouflaged creature of the deep; and we explore starfishes’ five-fold symmetry with Dr Imran Rahman. Khimlal Gautam, Mountaineer and Chief Survey Officer for the Government of Nepal, tells us of the near-death experience he had when checking the height of Mount Everest. And finally, axolotl expert Dr Elly Tanaka is astonished at the dedication of CrowdScience presenter Alex Lathbridge to the subject of her research. Presenter: Anand Jagatia Producer: Ben Motley Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Managers: Donald MacDonald and Giles Aspen (Photo: Lost in formulas Credit: Cimmerian via Getty Images)

The Moon has always sparked human curiosity. It governs the tides and biological rhythms. It’s inspired myths and stories. It’s inspired us to reach out and explore it. And it's certainly inspired CrowdScience listeners, who have sent us a host of questions about it. And in a special lunar-themed episode we’ve brought together a panel of astronomers and planetary scientists to help answer them. What would life be like if there was no Moon? Would there even be life? Or what if we had two moons? Are the Moon and Earth equally battered by meteors? What would happen if an asteroid collided with the Moon? And could the Moon ever escape Earth’s gravity? Anand Jagatia is joined by Prof Sara Russell, Head of the Planetary Materials Group at the Natural History Museum in London; Prof Neil Comins from the University of Maine, author of the book What if the Moon didn’t Exist?; and Prof Katarina Miljkovic from Curtin University in Perth, Australia. Presenter: Anand Jagatia Producer: Jeremy Grange Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Andrew Garratt (Photo: Landscape with the rising of the full moon during the golden hour Credit: Jose A. Bernat Bacete via Getty Images)