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CrowdScience

CrowdScience

BBC World Service 495 Episodes Sep 18, 2026

CrowdScience takes listener questions about life, Earth, and the universe to researchers at the frontiers of knowledge. Each episode explores a different scientific mystery, from the everyday to the cosmic. The show is produced by BBC World Service and features experts who provide clear, engaging answers.

Episodes

How many dead people are on the internet?
How many dead people are on the internet? Sep 18, 2026 2047 CrowdScience listener Devin in Canada has just had a baby. Worried that all the good email addresses might be taken by the time his child needs one, he has already set up an account. But it got him wondering: how many email addresses belong to people who have died? From websites and blogs to email accounts, social media profiles, gaming avatars and even our conversations with AI, we’re all leaving
Can my veggie sausages save the world?
Can my veggie sausages save the world? Sep 11, 2026 1588 CrowdScience listener Lisa, who is from South Africa but now lives in the UK, has been a vegetarian for many years. Sometimes though, she still finds herself craving meats – like spaghetti bolognese or a burger. To satisfy these cravings, she eats ‘alt-meats’, products meant to look and taste like meat but made from vegetables. This has her wondering though, are these alternative meats better for
Why do I love rollercoasters?
Why do I love rollercoasters? Sep 4, 2026 1749 Your heart pounds, your chest tightens, your stomach drops and your legs feel weak and shaky. Your palms are sweating and a tingling rush spreads through your arms and fingertips as your brain is overwhelmed with feelings of tension and fear. And yet, you’ve asked for this. You wanted to be on this ride, at this theme park, hurtling towards the ground at a frightening speed. But why? An adrenaline
How do electric fish make electricity?
How do electric fish make electricity? Sep 2, 2026 1589 Some fish can deliver electric shocks with four times the voltage of the electricity in your plug sockets at home . Crowdscience listener Mouhammed in Cameroon was stunned by this, so he charged us with finding out how they do it. Presenter Caroline Steel heads to Bayreuth in Germany to meet some eels who have this amazing ability. Dr Stefan Schuster and Susanne Proschke introduce us to their coll
Why am I warm blooded?
Why am I warm blooded? Aug 21, 2026 1588 CrowdScience listener Matt wants to know why he's warm blooded. He started thinking about this when he was watching some ants during the recent heatwave in Europe and wondered why their blood didn't boil. What are the pros and cons of being warm-blooded like us or cold-blooded reptiles like lizards? Caroline Steel meets evolutionary biologist Dr Manuel Leal from the University of Missouri in the U
Why can't I concentrate?
Why can't I concentrate? Aug 14, 2026 1589 Why is it hard to concentrate, and why does it feel like such hard work? The CrowdScience inbox is full of questions like that, so for this show we’re concentrating on concentration and focusing on how we focus. We’ll be answering questions about the extra energy the brain uses when we’re concentrating, whether mental effort can tire you out more than physical effort, why we zone out when faced wi
Why is TB still killing people?
Why is TB still killing people? Aug 7, 2026 1589 Tuberculosis kills more than a million people every year. It’s the world’s leading cause of death from a single infectious agent. This is despite the fact that we've had a cure for TB since the 1940s and a vaccine that’s over 100 years old. So why is TB still causing so many people to die? That’s what CrowdScience listener John in Tanzania wants to know, and presenter Marnie Chesterton is on the
Will I get hit by a meteor?
Will I get hit by a meteor? Jul 31, 2026 2220 Stare up at the night sky, and if you’re lucky, you might see a shooting star. Some people might make a wish, but CrowdScience listener Scott in California in the USA, thinks differently. He’s wondering how dangerous they might be. Shooting stars are actually meteors, ending their incredible journey whizzing through the depths of space by burning through our atmosphere, and crashing down to earth.
Is anything truly random?
Is anything truly random? Jul 24, 2026 1629 We’re delving into the CrowdScience archive to give you another chance to hear an award-winning show from 2025. 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
Are there diseases in space?
Are there diseases in space? Jul 17, 2026 1588 Space missions are searching for evidence of extra-terrestrial life. CrowdScience listener George in Kenya wants to know what could be up there, and if there’s a risk it could harm humanity. With rovers currently analysing samples on Mars, missions searching for the building blocks of life on Jupiter’s icy moons, George’s concern that there could be diseases in space is timely. Presenter Anand Jag
What are these strange rocks?
What are these strange rocks? Jul 10, 2026 1588 CrowdScience listener Liana from Canada got in touch to ask about some very specific rocks she’d seen on an island in Indonesia – jagged, rugged and a very strange shape: hexagonal. They were in long columns, and clicked together like a jigsaw. But what are they, and how did they get there? Across the world in the UK, CrowdScience listener Sarah emailed us to ask about the famous rocks of the Gian
How did plants evolve to attract insects?
How did plants evolve to attract insects? Jul 6, 2026 1588 Many plants need pollen from another plant of the same species in order to reproduce, but they don’t have legs so they can’t simply walk around looking for a mate. As a result, many of them rely on animals to transfer pollen from one plant to another. They’ve developed a hugely diverse range of techniques to attract them, including their appearance, taste and smell. CrowdScience listener Alice in

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