Crowdscience

CrowdScience listeners come in all shapes, sizes and ages. This episode is dedicated to our younger listeners who, as we’ve learned before, are experts at asking those superficially obvious questions that for parents, are anything but easy to answer. To start off with, Sylvia, asks why elephants are so big? As we hear from our expert – mammals were at one time, much larger – so perhaps the question should be, why aren’t they bigger? We investigate what drives body size in the animal kingdom.Presenter Marnie Chesterton, together with our ‘cub’ reporter Arlo, goes in search of the most brilliant scientific minds to respond to a slew of other queries. Shambhavi, from Singapore wonders why humans have five digits on each hand? And Benni from California asks why dogs don’t get sick when they drink from muddy puddles? Do dogs have some amazing ability to fight off viruses and bugs?Beyond the confines of our planet, we’ve also got a question from Olivia, from Sydney, Australia, who regularly contemplates the univers

We’ve probably all got a friend who sings along wildly out of tune - or maybe you are that person. But why are some of us apparently tone deaf, while others can hold a melody? Can you train yourself to sing in tune, or is it mostly down to raw talent?These musical questions, from CrowdScience listeners Jenny and Anastasia, certainly struck a chord with us. Anastasia loves to sing but her friends tell her she’s off-key - or that “a bear trod on her ear,” as they say in her native Russia. Is it possible for her to improve her singing voice, and what are the best ways of going about it?Both musicians and scientists help us tackle these questions, and explain what’s going on in our ears, brains and throats when we try to sing the right notes. We learn about congenital amusia, a condition which makes it almost impossible to tell if you’re in tune or not, and attempt to tease out the relative influence of our genes and our environment when it comes to musical ability.Presented by Marijke Peters and produced by Cath

All living things are related to each other, from elephants to algae, e-coli to humans like us. Within our cells we hold genetic information in the form of DNA or RNA. But despite viruses sharing these molecules, many scientists don't consider them to be 'life'. Viruses cannot reproduce on their own, but some can insert their DNA into a host to pass genes sideways through the branching tree of life. As a result, viruses’ relationship with life is.... complex. Two of our listeners had viruses on the mind, so they sent in the same question to CrowdScience. Senan from Singapore and Melvin from South Africa want to know how viruses began to see if this can tell us whether they shared a common ancestor with humans. To dig into this complexity Marnie Chesterton speaks with an expert on Koala genetics – Dr Rachael Tarlinton. Koalas are in the middle of tackling a retroviruses, a type of virus that plants DNA into our cells as a reproduction strategy. Her research could reveal why humans life has so much viral DNA w

Curious CrowdScience listeners have suddenly been struck by the oddity of their behaviours. Elise ponders why she blushes. Thankfully, listener David is a vascular surgeon and knows a thing or two about blushing, as he performs operations on people debilitated by constant red-dening. He has some answers for us, but asks why did blushing evolve?In the past, red cheeks have been linked to necrophilia, repressed cannibalism, and even a de-sire for men to experience menstruation! Thankfully, research has come a long way since then, as blushing experts Peter de Jong and Corine Dijk explain. Scientists believe that it evolved as a nonverbal signal to show someone you’re sorry or that you care about what they think. This would have important for our survival in the group, en-suring we didn’t get into a fight or get kicked out the group. Anand Jagatia gets to grips with blushing and other bodily behaviours – including a question from Thai listener Nitcha who wonders why we yawn as well as a question from Mohamed in G

Crowdscience solves a range of listeners’ cosmic mysteries, from the reason we only ever see one side of the moon, to why planets spin, and discover the answer can be found in the formation of the solar system. We talk to astronomer Dr Carolin Crawford to understand how stars are made, and investigate the art of astronomy with journalist Jo Marchant, hearing how the ancient Greeks came up with a zodiac long before the invention of a telescope, revealing an intimate relationship between humans and the night sky.Presenter: Marnie Chesterton Producer: Marijke Peters [Image: The Solar System. Credit: Getty Images]

Why am I embarrassed to be naked? Chumbuzzo in Zambia wonders. And what would happen if we ditched our clothes and embraced nudity? Presenter Anand Jagatia and Producer Caroline Steel spend the day naked with other naturists to see if they can shift their embarrassment. Maybe there are good evolutionary reasons to cover up or perhaps we are contributing to inequality and negative body image by hiding our real selves? Marnie Chesterton explores different cultural attitudes to nudity and finds out about the science behind embarrassment. Clothes optional. Presented by Marnie Chesterton. Produced by Caroline Steel for the BBC World Service

Many of us willingly subject ourselves to pain and irritation by eating chilli. CrowdScience listener Tina wonders what’s driving this apparent masochism: why does ‘feeling the burn’ make so many of us feel so good?It’s just one of several tasty questions we tuck into in this episode. Also on the menu is stew: why does it taste better the next day? Listener Helen’s local delicacy is Welsh cawl, a meat and vegetable concoction. Tradition dictates it should be eaten the day after it’s made, but is there any science behind this?And we finish the meal with cheese. Listener Leander asks what makes some cheeses blue, some hard and crumbly, and some run all over your fridge. How is milk transformed into such radically different end products?Presented by Marnie Chesterton and Alex Lathbridge Produced by Cathy Edwards, Marnie Chesterton and Alex Lathbridge for the BBC World Service.[Photo:Woman eating red Chilli Pepper. Credit: Getty Images]

What does science say about controlling urination, and other bodily functions? We tackle three queries about peeing triggers, pooing positions and missing sweat. This episode CrowdScience presenter Marnie Chesterton poses some of the best listener follow-up questions that have landed in our inbox to a panel of experts.Listener Samuel in Ghana is wondering why watery sounds seem to induce urination. Producer Melanie Brown heads out to survey whether this is the case for individuals in an actual crowd at a public fountain in London. And urologist and trustee of the International Continence Society Marcus Drake talks Marnie through how he uses the sound of running water during his work as a hospital doctor helping patients with common but distressing peeing issues, and the limitations of research into this question.And he’s not the only listener who wants us to dig deeper into topics we’ve explored on the show before. Anna in Tokyo also got in touch after hearing our show about toilets, to ask if there is a toil

If you’re one of the millions of people who used lockdown to try something new like baking sourdough bread, you may well be wondering what’s happening chemically inside your loaf, especially if the end result keeps changing. Well, you’re not alone. Listeners Soheil and Sean are both keen bakers but want to know more about the thing that makes bread rise: yeast. What is yeast? Where does it come from and can you catch it? And how hard is it to ‘make’ yourself? Soon after lockdown took effect, commercial supplies of the stuff disappeared from supermarket shelves across the globe. The shortage also affected brewers the world over. A big fan of yeast in most of its forms, Marnie Chesterton took on the challenge of creating her own. She talks to the brewers who hunt rare strains to create the perfect beer, and hears from the biologist who says these amazing microbes, used for thousands of years, could be used to make food production more sustainable. And she discovers how this simple ingredient could be instrument

Squelching into the science of slime, Chhavi Sachdev seeks to find out why it took so long for listener Helen Tyson to remove slime from her fingers, after she picked up a tiny slug while gardening. This unfortunate and hugely repulsive experience set Helen to wonder what it is about the structure of slug slime that makes it gloopy, so she sent Chhavi to meet with slug slime expert Professor Andrew Smith who reveals how the complex molecular structure of this pervasive fluid makes it so difficult to scrub off.Slime is used by all sorts of creatures including the Giant African Land snail, which invaded India by hitching a ride on imported timber. But invasive species biologist Dr TV Sajeev reveals that these snails are themselves giving a lift to another meningitis-causing parasite that can infect people. Chhavi looks for these massive molluscs in her own garden in Mumbai. Marine biologist Helen Scales describes how animals can use slime for catching food, mating, defence, or even transportation, and Chhavi sp

Anyone else had their flight cancelled? The COVID 19 pandemic has had a huge impact on air travel – air traffic in 2020 is expected to be down 50 per cent on last year. But beyond the obvious disruption to business and people’s lives, how might the quieter skies affect our weather and climate? One curious listener, Jeroen Wijnands, who lives next to Schiphol airport in the Netherlands, noticed how there were fewer clouds and barely any rainfall since the flights dropped off. Could airplanes affect our local weather? Also, did we learn anything from another occasion when airplanes were grounded, during the post-9/11 shutdown? How will the current period impact our future climate? Marnie Chesterton investigates this question and discovers some of the surprising effects that grounded aircraft are having: on cloud formation, forecasting and climate change. Presenter: Marnie Chesterton, Producer: Dom Byrne[Photo:Commercial airplane parking at the airport. Credit: Getty Images]

Listener Avalon from Australia wants to know why people use conspiracy theories to explain shocking events. Are we more likely to believe conspiracy theories in times of adversity? What purpose do conspiracy theories serve in society? Marnie Chesterton speaks to the scientists to explain their popularity, even in the face of seemingly irrefutable evidence. Presented by Marnie Chesterton. Produced by Caroline Steel for the BBC World Service.Image: All-seeing eye of God inside triangle pyramid. Credit: paseven, Getty Images

These days we’re more acquainted with soap than ever before, as we lather up to help stop the spread of coronavirus. And for CrowdScience listener Sharon, this set off a steady stream of soapy questions: how does soap actually work? How was it discovered in the first place, long before anyone knew anything about germs? Are different things used for washing around the world, and are some soaps better than others? We set up a CrowdScience home laboratory to explore the soap making process with advice from science-based beauty blogger Dr Michelle Wong, and find out what it is about soap’s chemistry that gives it its germ-fighting superpowers. Soap has been around for at least 4000 years; we compare ancient soap making to modern methods, and hear about some of the soap alternatives used around the world, like the soap berries of India.And as for the question of whether some soaps are better than others? We discover why antibacterial soaps aren’t necessarily a good idea, and why putting a toy inside a bar of soa

Think of the oceans and an empty and peaceful expanse relatively untouched by humankind might come to mind. But is this peace an illusion? CrowdScience listener Dani wants to know if the noise of shipping and other human activity on the oceans is impacting on sea life.To find out, Marnie Chesterton takes a deep dive to learn how marine animals have evolved to use sound; from navigating their environments to finding a mate or hiding from prey. She then speaks to a scientist who is using acoustic observatories to track the many ways human activity - like sonar and shipping - can interfere.Marnie virtually visits a German lab which tests the ears of beached whales, dolphins and seals from around the world to try and ascertain whether they suffered hearing damage, and what might have caused it. What other smaller creatures are negatively impacted by underwater noise? Marnie learns that acoustic trauma is more widespread than first thought.As human life continues to expand along ocean waters, what is being done to

Worms are not the cutest of creatures. They’re slimy, often associated with death and tend to bring on feelings of disgust in many of us. But listener Dinesh thinks they’re underrated and wants to know whether earthworms could be the key to our planet’s future agricultural success? He’s an organic farmer in India’s Tamil Nadu province who grows these annelids to add to the soil, and he wants Crowdscience to find out exactly what they’re doing. Anand Jagatia dons his gardening gloves and digs the dirt on these remarkable creatures, discovering how they can help improve soil quality, prevent fields from becoming waterlogged, and improve microbial numbers, all of which has the potential to increase crop yield.But he also investigates the so-called ‘earthworm dilemma’ and the idea that in some parts of the world, boreal forest worms are releasing carbon back into the atmosphere, which could have dangerous consequences for climate change.(Photo:

Shoes are a surprisingly recent human invention. But running isn’t. That means for most of our time on the planet, we’ve run barefoot. Today, in most countries it’s rare to see people out in public without shoes, let alone running. But might our aversion to the free foot be causing us pain?CrowdScience mega-fan Hnin is an experienced runner, she enjoys ultra-marathons back home in Australia. But about six months ago she developed extreme foot pain, the condition ‘Plantar Fasciitis’, and this has meant she had to stop doing what she loves. She reached out to CrowdScience presenter Chhavi Sachdev, to find out if barefoot running could reduce her pain and improve her performance. Simply put, is barefoot running better? In an attempt to find Hnin some answers, Chhavi hits the ground… running. Literally throwing off her own shoes on the streets of her home city of Mumbai, India, to see how feeling the ground can change her whole gait. And with Prof. Dan Lieberman, Chhavi learns what sets the human runner apart fr

If you put one person’s blood into another person , sometimes it’s fine and sometimes it’s a death sentence. French physician Jean-Baptiste Denis discovered this when he performed the first blood transfusion back in 1667. He put the blood of a lamb into a 15-year boy. The teenager survived but Denis’s third attempt killed the patient and led to a murder charge.In 1900, Austrian doctor Karl Landsteiner discovered the reason for this lottery – blood types. The red blood cells in our bodies are decorated with different marker molecules called antigens. These define us as A, B, AB or O blood type. And this is just one of 38 different systems for classifying our blood. CrowdScience listeners have discovered that we aren’t the only animal with blood types and want to know more. Dogs have 12 different blood groups, so how do they cope when they need a transfusion? CrowdScience meets some very good dogs who donate a pint to the pet blood bank in return for a toy and a treat. Each pint saving up to 4 other dogs’ live

What exactly it means to be conscious has long been a question of profound debate amongst philosophers, and more recently, scientists. There are no easy answers, and it gets even trickier when you start asking whether animals are conscious: how can you find out about their subjective experience when they can’t tell you about it?Never afraid to tackle the impossible, CrowdScience is looking for answers after listener Natalie got in touch. She has lived with her cat for years and has a strong sense that he has thoughts and feelings: he has his own personality, acts in complex ways, and even has ‘grumpy days’. But is this consciousness? Is there any way of scientifically testing for it? How different from our own inner world is that of a cat, an octopus, or a bumblebee? And if we can find any answers to these puzzling questions, how does that affect the way we treat animals - not just our pets, but all the animals we share our planet with?We meet Natalie and her cat, and discover how scientists have explored the

We were bowled over by a question from one CrowdScience listener in Australia wants to know how likely it is that the atoms in his body have been used in someone else’s body? We all like to think we are unique; no one is quite like us. But is that really true?Presenter Marnie Chesterton tackles Moshe’s question with help from every area of science. From geologists helping us work out how many atoms are on the Earth’s surface to biologists helping us work out how many atoms each body uses. Perhaps we are much less special than we think.Presented by Marnie Chesterton. Produced by Caroline Steel for the BBC World Service. (Photo:

Have you ever broken up a fight? Or pushed someone out the way of an oncoming vehicle, only to be hit by it yourself? Most of us probably haven’t taken as many risks as listener Alix, who has put herself in peril to save strangers on several occasions, and she wants Crowdscience to investigate why. At a time when medical professionals have to weigh up the personal dangers of working on the frontline of the Coronavirus crisis, it’s a particularly timely question. Marnie Chesterton finds out why it’s a good thing that children push the boundaries of what’s safe during playtime, because it makes them less anxious adults. And she questions the existence of the so-called bystander effect, discovering how evolution has ensured we’re a much braver species than we sometimes give ourselves credit for. But she hears from some social scientists who say there’s no such thing as a ‘hero’, however likely they are to intervene to help others.The virtual reality experience in this programme was created by the Human-Computer