Crowdscience

Why do humans have wisdom teeth if so many of them get removed soon after they appear?Wisdom teeth, the third molars in the back of our mouths, are so called because they normally appear in late teenage, early adulthood – the time in life we supposedly have learned some wisdom. But around 25% of people don’t develop all four. Of those that do emerge, it is not uncommon for them to appear at nasty angles, jutting into the tooth next door causing potentially dangerous infections and pain. Because of this, for decades many people have them surgically removed. Listener Khaleel was preparing to have his remaining wisdom teeth removed when he wrote to CrowdScience to ask about them. Given that they can seem to cause more harm than good, why has evolution resulted in these troublesome teeth? But many people have perfectly uneventful relationships with their wisdom teeth, so have we perhaps removed more than we needed to over the years?Anand Jagatia chews it over with the help of surgeons and dentists to try to extra

When the first person set the very first clock, how did they know what time to set it to? This question, from listener Chris in the UK, sends CrowdScience off on a quest into the history of timekeeping. From sundials to water clocks, from uneven hours to precision seconds determined by the vibration of an atom, we examine how we came to measure time. We visit possibly the oldest working mechanical clock in the world to discover how its time was originally set; and hear how the time we go by today is not quite the same as it was in the past. Will all this be enough to solve Chris' question, or has he stumped the team? Featuring:Ian Westworth, Clock Mechanic Dr. Chad Orzel, Associate Professor of Physics and Astronomy at Union College Anna Rolls, Curator of Clocks, Clockmakers’ Museum Peter, Guide, Salisbury Cathedral Dr. Jun Ye, Physicist at NIST (National Institutes of Standards and Technology) and The University of Colorado, Boulder.Presenter: Caroline Steel Producer: Margaret Sessa-Hawkins Editor: Cathy

In 2011, CrowdScience listener Amanda survived the devastating earthquake in Christchurch, New Zealand.It arrived unannounced - as all earthquakes do - leaving her with no time to prepare a response. So Amanda wants to know whether science will ever be able to give us advance warning of quakes.To explore her question CrowdScience heads to New Zealand to meet listener Amanda, as well as the brains behind the country’s earthquake forecasting models. We dig in a field for thousand-year-old tectonic clues that could help us understand when the next earthquake might strike. But even if we could get a head start against a quake, would we respond in the right way?Please note: earthquake response advice varies by location. Please check local guidance and individual building procedures.Featuring:Nicola Litchfield, Principal Scientist in Paleoseismology at GNS, Wellington, New Zealand Matt Gerstenberger, Seismologist and leader of the National Seismic Hazard Model, GNS, Wellington, New Zealand Andy Howell, University o

Have you ever been through a romantic break up, unable to shift the ex from your thoughts? You are, obviously, not alone…Listener Elkin, experienced just that. But rather than wallowing in self-pity, he sought out an explanation. Where better to get it, than from CrowdScience. Now, Alex Lathbridge is putting on his thinking cap to find out why we daydream?Presenter: Alex Lathbridge Producer: Harrison Lewis Editor: Martin Smith Production: Jonathan HarrisFeaturing:Giulia Poerio, Lecturer in Psychology, University of Sussex. Kalina Christoff, Professor of Psychology, University of British Columbia. Eli Sommer, Israeli Professor of Clinical Psychology, University of Haifa. Sophie Forster, Reader in Psychology, University of Sussex(Photo: Man daydreaming surrounded by clouds. Credit: jacquesdurocher / Getty Images)

Presenter Marnie Chesterton and the team pit their wits against a multitude of mind-bending puzzles from an old TV gameshow - all in the name of answering a question from Antonia in Cyprus: how do we work out how clever someone is? Is IQ the best measure of cleverness? Why do we put such weight on academic performance? And where does emotional intelligence fit into it all? In the search for answers Marnie and the team are locked in rooms to battle mental, physical, mystery and skill-based challenges, all against the clock. Unpicking their efforts in the studio are a global team of cleverness researchers: Dr Stuart Ritchie from Kings College London, Prof Sophie von Stumm from York University and Dr Alex Burgoyne from Georgia Institute of Technology in the US. They are challenged to face the toughest questions in their field: Why do men and women tend to perform differently in these tests? Is our smartness in our genes? And what about the Flynn Effect – where IQs appear to have risen, decade after decade, arou

What evidence is there for a semi-aquatic period in human evolutionary history? That’s the question that’s been bothering listener Dave in Thailand. He thinks our lack of hair and love of water might indicate that, at some point, we were more water-based than we are now. But what does science have to say on the matter? The theory that our ape ancestors returned to the water for a phase in our evolutionary history is a controversial idea that most scientists disagree with. Anand Jagatia chats to Dr Melissa Ilardo, assistant professor at the University of Utah, about our dive reflex - a physiological response we display when submerged underwater, which helps direct oxygen towards vital organs. But this is not a response that is unique to humans - it is found in all mammals. Experts say it developed long before all apes split off in the evolutionary tree. To find out more about the theory itself Anand hears from John Langdon, emeritus professor at the University of Indianapolis. He explains why the aquatic ap

Our question this week comes from a father and his two young boys. They want to know whether it’s possible to plant enough trees to soak up all the extra carbon we are putting into the atmosphere? The quest to find answers takes us to a remote reforestation project in the Carpathian Mountains in Romania which could be a model for other projects looking to tackle the climate crisis through reforestation. We speak to experts to find out how much tree planting and reforestation can do in helping combat the climate crisis. Presenter: Caroline Steel Producer: Margaret Sessa-Hawkins Editor: Richard Collings

Noise pollution from vehicles in the public space has a huge impact on human health. But as the world switches to quieter electric-powered means of transport there’s a debate about whether we will actually see any noticeable improvement to our quality of life. Discovering more than just engineering solutions to the problem, CrowdScience visits one of the world’s loudest cities, Mumbai in India. It is a place where noise has become a way of life. But is that all about to change? Presenter: Alex Lathbridge Producer: Richard Walker Editor: Richard Collings

Welcome to Part 2 of our year-end extravaganza and the final episode of 2023! We’ve had a brilliant year hunting down the answers to your science questions - on everything from food and phobias to friction and flying - and in this episode presenter Anand Jagatia is revisiting some of the best stories we covered. We’re bringing you some extra juicy bonus content that we couldn’t fit in to those shows first time round. Hannah Fisher joins Anand to revisit an episode she produced about the microbiome, the community of tiny organisms living both on and inside us. During that show Hannah took presenter Caroline Steel to a microbiome museum in the Netherlands called Micropia. And one thing from Micropia that never got aired was the kiss-o-meter, a device that measures how many microbes you exchange when you kiss! Micropia curator Jasper Buikx explains the science behind the kiss-o-meter, and then Caroline Steel tries it for herself! Microbes aren’t just living on and in humans and animals - they’re pretty much eve

Welcome to Part 1 of CrowdScience’s year-end extravaganza! It’s an extra-festive episode this week. For those who celebrate it, Christmas is the perfect time to pause and look back at the year just gone. Here on CrowdScience we’ve had a great 2023: we answered dozens of listener questions, ranging from climbing plants and ostriches to panic attacks and the weight of the internet. This week presenter Anand Jagatia magically appears with a Santa’s sack full of special features. We’re catching up with some of our favourite guests from the past year and answering some of the extra questions that we never got the chance to cover. First up we hear from presenter Tim Clare who we first heard in the episode “Why do some people have panic attacks?” He takes Anand through his new book – it's about board games: why we play them, how they’ve existed throughout history and what he’s learned about himself in the process of writing it. Then it’s time for a bonus question. The CrowdScience team often get questions about noi

Seeds are crucial to human existence – we eat them, we grow them and then we eat what they become. But what is a seed and how come it can sit there doing nothing for ages and then suddenly, when the conditions are right, burst into a plant?That’s what CrowdScience listener Anke has been wondering. She runs an aquaponic salad farm near Stockholm in Sweden and she germinates thousands of seeds every week. With a bit of moisture and light, seeds that have been dormant for months can become leafy greens in just a few weeks. So are seeds alive, are they on some kind of life support, or is something else going on?Presenter Caroline Steel sets off to Sweden to meet Anke, before heading for the Nordgen seed bank near Malmö. There she discovers how seeds being stored for future generations are tested for viability, and wonders what’s going on inside a seed that allows it to remain asleep before suddenly coming to life. How does a seed decide that the time is right?We hear about one of the world’s longest running scien

If, like this week’s Crowdscience listener Lili, you enjoy working out in the gym, you may have wondered where your fat disappears to when you exercise? The short answer is that we convert it to energy that powers a whole range of physical processes - from breathing to walking as well as lying down and doing nothing. But the science behind energy expenditure is a little more complicated than that. Presenter Anand Jagatia jumps on an exercise bike to have his metabolism measured and learns that he may be relying on an entirely different source of fuel as he works up a sweat. Is all that hard work worth the effort it involves? Recent research suggests there is a limit to the number of calories humans can burn and that engaging in physical activity is not always a sure-fire way to keep trim. So if working out is not the best way to lose weight, how about harnessing our own fat to tackle the complications of obesity? It used to be thought brown fat was exclusive to babies (and bears) but we now know adults ha

*Warning* This episode includes references to suicide. When listener Ben heard about a Kenyan “starvation cult” in the news, he wondered whether the members of this group had been brainwashed. Is it possible to control someone’s mind? In this episode presenter Caroline Steel learns how easily people can be influenced. She hears what it’s like to be part of a cult, and gets to the bottom of a decades-long debate: does brainwashing exist? And, if so, how does it work? Presenter: Caroline Steel Producer: Florian Bohr Editor: Richard Collings Production Co-ordinator: Jonathan Harris Studio Managers: Donald McDonald and Emma Harth Featuring: Anthony Pratkanis, Emeritus Professor of Psychology, University of California, Santa Cruz Alexandra Stein, Honorary Research Fellow, University of Sussex Eileen Barker, Professor Emeritus of Sociology, London School of Economics (Image: Washing a brain. Credit: Cemile Bingol / Getty Images).

CrowdScience listener Michael wants to know whether the brain responds differently if we listen to books instead of reading them. Do we retain information in the same way? And is there a difference between fiction and non-fiction? Anand Jagatia finds out whether curling up with a good book is better than putting on his headphones. She is speaks to Prof Fatma Deniz from the Technical University of Berlin; Prof Naomi Baron from American University, Washington DC; Prof Patrick Nunn from the University of Sunshine Coast, Queensland and The Guesthouse Storytellers.Presenter: Anand Jagatia Producer: Jo Glanville Editor: Richard Collings Production co-ordinator: Jonathan Harrison Sound engineer: Andrew Garratt(Photo: Senior man wearing headphones listening to an audiobook. Credit: pixdeluxe/Getty Images)

Lying is something all humans do. We find it in every culture around the world. It’s in the world of work, in our relationships and online. It’s all pervasive and hard to escape. Our question this week is from listener Anthony from Cambodia. He asked us to find out why we lie, and wants to know how conscious we are of the lies that we tell? CrowdScience’s Caroline Steel is in the hot seat, on a journey where she will attempt to untangle the complex story behind lying. It’s a subject scientists and psychologists have been studying for a long time. It’s also something writers, philosophers and theologists have been interpreting for thousands of years. But we’re only now really starting to get to grips with how it works as a human behaviour. There are lies in our folklore, lies in the media and also lies in everyday conversation. It’s something we’ve all had to learn to navigate at some point in our lives. In this episode the CrowdScience team unravels the mysteries surrounding the behaviour and the art of l

Our planet is quickly approaching 1.5 degrees Celsius of warming (2.7 degrees Fahrenheit). Scientists say we might cross this milestone in just six years. Listener Julian wants to know what life will look like on the other side of that threshold. With the help of climate scientists, the BBC’s Anand Jagatia dives into the worlds of virtual climate models. From heatwaves to higher humidity indices to extreme precipitation and drought, he gets a picture of what's to come. We also venture to places that are warming both faster and more slowly than the global average. In a remote village in Alaska residents are already dealing with life-changing permafrost thaw and ground that's melting beneath their feet. Permafrost expert Sue Natali tells us what this unexpected thawing ground means for the planet as it releases carbon and methane we weren't necessarily counting on. In Indian cities, temperatures were already high, but they're not rising as quickly as climate scientists had initially predicted. We hear why thi

“You are what you eat” is a well-known saying. But is it really true? That’s what we explore in this week’s CrowdScience thanks to a question from listener Claire from Australia. We each have trillions of tiny microbes and bacteria inside our bodies, living in our mouths, skin, ears and even in our eyes. Each community of microbes and bacteria is known as a microbiome. The most populous of these is in our gut, with hundreds of trillions of organisms and bacteria helping digest the food we eat. Our gut microbiome is affected by lots of things but mainly by our diet. With our gut microbiome forming such a massive part of our insides, people have long suspected that what we eat impacts how we feel. Presenter Caroline Steel investigates. She speaks to a professor of Psychiatry, Jane Foster, to find out how interconnected our microbiome and our brain really are. Professor Foster also explains the different ways in which our microbiome and brain communicate. Do we really know what role diet plays in mental healt

Why are some animals cute, cuddly, adorable – and some are slimy, creepy and downright weird? This edition of Crowdscience, recorded in front of a live audience, comes to you directly from the world-famous Green Man Festival in Bannau Brycheiniog National Park in Cymru (Wales). The programme recording was powered entirely by hydrogen. Our inbox has been bursting at the seams with questions about creepy crawlies, deep sea beasties, cheeky monkeys, endangered species and animals of all shapes and sizes. So, we rounded up a panel of experts to get some answers! Surrounded by 25,000 people trudging merrily through the mud, pelted with torrential rain, underscored by the warm hum of revelry, the BBC’s Marnie Chesterton speaks with Dr David Jones from the Natural History Museum, an expert on creepy crawlies and someone who spends a considerable amount of time thinking about earthworms, ants, and termites. Also joining us is Jess Savage, a researcher from the Institute of Zoology in London who’s an expert on ocean-

Salmon are one of the world’s most popular fish. And - in terms of the size of the industry - they’re also the world’s most valuable. They provide crucial proteins and fatty acids to many people’s diets. But like other species of fish, their production is undergoing a historic change. Plenty of salmon is still caught from the wild, but the majority is now farmed off the coasts of countries like Norway or Chile. With global demand on the rise, listener Jodie from Australia wants to know: which is healthier, farmed salmon or wild? CrowdScience’s Marnie Chesterton is on the case! Her first stop: a remote loch in the west of Scotland, where salmon company Mowi rears thousands of the fish in big, open-water nets. Marnie takes the chance to see for herself what salmon farming actually looks like. She then speaks to aquaculture nutritionist Stefanie Colombo, who researches the nutrient content of different types of salmon. Stefanie breaks down the health positives and negatives of each, as well as what causes some o

CrowdScience listener Kristine from Wisconsin in the USA wants to know why herbs and spices taste so good to so many of us. She’s intrigued to know if there's evidence that herbs and spices can keep us healthy. Anand Jagatia visits the historic naval city of Portsmouth in the UK, where exotic spices from around the world were first brought in from the East Asia more than 600 years ago. He’s on a journey to find out why many of us think spices are delicious. But are there also nutritional benefits to seasoning our food with them? Anand asks what science or studies are there to show that eating herbs and spices can be beneficial for our health? Presenter: Anand Jagatia Producer: Joanna Hall Assistant Producer: Jonathan Harris Editor: Richard Collings Studio Technicians: Bob Nettles & Steve Greenwood Contributors: Prof. Lindell Bromham, evolutionary biologist, Australian National University Dr. Kanchan Koya, Molecular Biologist and founder of the Spice Spice Baby website Dr. Beronda L. Montgomery, p