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CrowdScience

BBC World Servicewww.bbc.co.uk

We take your questions about life, Earth and the universe to researchers hunting for answers at the frontiers of knowledge.

Episodes

Can we grow a conscious brain?

Philosophers have long pondered the concept of a brain in a jar, hooked up to a simulated world. Though this has largely remained a thought experiment, CrowdScience listener JP wants to know if it might become reality in the not-too-distant future, with advances in stem cell research. In the two decades since stem cell research began, scientists have learned how to use these cells to create the myriad of cell types in our bodies, including those in our brains, offering researchers ways to study ...

Oct 15, 202136 min

Does the planet need snails?

Snails are a major enemy of gardeners around the world, invading vegetable patches and gobbling prize plants. CrowdScience listener Alexandre reckons he’s removed thousands of them from his garden, which got him wondering: apart from eating his garden to the core, what’s their wider role in nature? Would anyone or anything miss them if they suddenly disappeared? And for that matter, what about other creatures? We all know how complex biodiversity is, but it seems that some animals are more impor...

Oct 08, 202135 min

Do plants have immune systems?

In the past 18 months we have heard lots about the human immune system, as we all learn about how our bodies fight off Covid-19 and how the vaccine helps protect us. But this got listener John, in Alberta, Canada, thinking about how trees and plants respond to diseases and threats. Do they have immune systems and if so, how do they work? Do they have memories that mean they can remember diseases or stressful events 5 months, or 5 years down the line, to be better prepared if they encounter the s...

Oct 01, 202132 min

How do flowers know when to bloom?

This year has been a weird one for UK gardeners – unpredictable spring temperatures meant flowers failed to bloom and throughout the rainy summer, slugs have been savaging salad crops. But why and when plants blossom is about more than just early cold spells and wet weather, and a listener in California has asked Crowdscience to investigate. Flowering is vital to both plants and us. Without it, they wouldn’t be able to evolve and survive (and we wouldn’t have anything to eat). Anand Jagatia hear...

Sep 24, 202133 min

How did eyes evolve?

Look into my eyes. What do you see? Pupil, lens, retina… an intricate set of special tissues and mechanisms all working seamlessly together, so that I can see the world around me. Charles Darwin called the eye an ‘organ of extreme perfection’ and he’s not wrong! But if the eye is so complex and intricate, how did it evolve? One listener, Aloyce from Tanzania, got in touch to pose this difficult question. It’s a question that taxed Darwin himself, but CrowdScience is always up for a challenge! Th...

Sep 17, 202135 min

Can we transfer electricity wirelessly?

Pioneering physicist and inventor Nikolas Tesla dreamt of connecting the world up through wireless communication and power. Despite demonstrating he could transfer power short distances his longer distance experiments were considerably less successful. But CrowdScience listener, George from Ghana, wants to know if now - more than one hundred years after Tesla’s demonstrations - his dream of wireless power is closer to becoming a reality. In countries where rugged landscapes make laying tradition...

Sep 10, 202134 min

Can we save our night skies?

Our connection to the night sky spans cultures and millennia: observing the stars and planets helped our ancestors navigate the world, tell stories about the constellations, and understand our place in the universe. But these days, for the vast majority of us, seeing the stars is getting harder. 80% of people live under light polluted skies, and in many cities you’re lucky to see a handful of stars at night. This state of affairs is bothering CrowdScience listener and keen stargazer Mo from Salt...

Sep 03, 202132 min

How did our ancestors sleep?

How we sleep is a topic of endless fascination and for some can, ironically be quite exhausting. Modern life has allowed us to invade the night, and those pesky late night work emails, social media and TV all conspire to limit our sleep or simply prevent us from a truly restful night. But if we travel back in time, did our ancestors master sleep any better? No air-con or electric fan for them on hot humid nights, and only smoky fires to keep them warm on cold, snowy nights. What if we go way bac...

Aug 27, 202127 min

Why is human skin so rubbish?

If you’ve ever fallen over and grazed your skin, maybe you wished it were made of stronger stuff. The tough hide of a rhinoceros or the protective armour of a stag beetle would do a better job. It’s a thought that’s been bothering CrowdScience listener Paul, who points out that our skin also suffers from acne, eczema and hives; it dries out; it bruises. In fact, human hide is so vulnerable that we cover our feet in other animals’ skin and our bodies in clothes just to make life more comfortable....

Aug 21, 202134 min

How can smart tech tackle climate change?

Humans are responsible for emitting over 40 billion tonnes of carbon dioxide into the atmosphere every year – and we all know that we need to reduce that figure to prevent devastating climate change. Listener Saugat wonders whether smart technology and artificial intelligence can help us do this more quickly? Green energy will go a long way to tackling the problem, but integrating wind and solar into our current electricity grid is complicated. CrowdScience hears how AI is being used at a wind f...

Aug 13, 202138 min

Can video games help me or harm me?

Today, up to 3 billion people around the world play video games, from candy based mobile puzzles to virtual battlegrounds filled with weapons. Many people have turned to gaming during the pandemic as a way of staying connected – but what does science really say about the impact of gaming? Does playing violent video games lead to violence in the real world? Do brain training apps really work? How much gaming is too much – can videogames really be addictive? And how can videogames help us to explo...

Aug 06, 202134 min

Do I really have to clean my recycling?

Reduce, Reuse, Recycle. It’s a well-known phrase that we all try and follow in our day to day lives. But are our current recycling habits the best they can be? It’s a hot topic at Crowdscience - multiple listeners have contacted Crowdscience with questions about the ins and outs of recycling. We follow one listener’s food waste to a processing plant to investigate whether or not it could be processed in our own homes. But aside from the food waste, what about the containers it comes in? We inves...

Jul 30, 202132 min

Am I a psychopath?

One CrowdScience listener finds herself unconcerned about much of the world’s problems, it leaves her wondering: am I a psychopath? Inspired by a previous episode on empathy, this listener asked is it true that psychopaths don’t empathise and what are the character traits of psychopathy? Marnie Chesterton talks with a diagnosed pro-social psychopath to find out. She also pays a visit to the Netherlands Institute for Neuroscience and gets into an MRI scanner to discover what is happening in her b...

Jul 23, 202136 min

Why do my cables keep getting tangled?

Anyone who has ever taken the Christmas lights out of the cupboard, only to discover they’re hopelessly tangled, will sympathise with this week’s listener Eric. He has a 45m garden hose that always seems to snarl up and snag when he waters his garden, and he wonders what he’s doing wrong? Marnie starts by discovering the important difference between tangles and knots, as she scales a cliff with an experienced climber who explains the way you tie rope is a matter of life and death. Physicists are...

Jul 16, 202132 min

Why is standing more tiring than walking?

Standing takes less energy than walking, so why does it feel more tiring? At least, it does for CrowdScience listener Nina. She can march for hours without getting tired, but her legs and feet get achy after just a short time standing still. It’s one of three walking-themed questions CrowdScience is tackling this week. Taking inspiration from our active listeners, Marnie Chesterton walks up a hill with Caroline Williams, author of a new book about why humans are designed to move. We find out how...

Jul 09, 202130 min

Why do I feel hungry?

Food. For all of us it is a basic necessity and for those lucky enough, it is something we spend a lot of time planning and enjoying. CrowdScience listeners certainly have a lot of food related questions; in this buffet of an episode Marnie Chesterton opens the fridge door to pick the tastiest. Starting with the seemingly simple question of what makes us feel hungry, and ending in outer-space, Marnie investigates flavour, nutrition and digestion. After a year when watching TV has become a core a...

Jul 02, 202136 min

What happened to my sense of smell?

It took a while before it was officially recognised as a major symptom of Covid-19, but loss of smell has affected up to 60 percent of people who have had the virus. And for a significant portion, smell continues to be an issue for weeks or months after their recovery. So what’s going on and how can you get your sense of smell back? We tend to think of our sense of smell as something universal – if it smells bad to me, it probably does to you but that is not the case for CrowdScience listener An...

Jun 25, 202127 min

Does my equator look big in this?

Scales don’t come planet-sized, so answering a question from David in Ghana may require some ingenuity, after all, calculating the weight of the Earth is a huge task. Using a set of weighing scales and a 400 year-old equation, Marnie Chesterton attempts to find out just how much the Earth weighs and is it getting heavier or lighter over time? But how would a planet gain or lose mass? Which tips the scales: meteorites falling from space or gases constantly escaping from our atmosphere? And does t...

Jun 18, 202137 min

Why do I have such a sweet tooth?

They say life is sweet. Well that’s certainly the case for CrowdScience listener Trevor in Poland who wonders why he can’t stop reaching for the cookie jar. He grew up drinking fruit juice with added sugar but wonders whether his genes could be as important as his environment when it comes to his sweet tooth, especially since his wife seem to be satisfied with mainly savoury snacks. The World Health Organisation says added sugar should constitute a maximum of 5% of our daily energy intake becaus...

Jun 11, 202138 min

What is the point of menstruation?

It's a topic that's taboo in many cultures, yet it's also something nearly every woman experiences – on average upwards of 400 times throughout her life: menstruation. Responding to a flood of questions from our CrowdScience listeners, Marnie Chesterton seeks to unpack how periods affect women physically, mentally and societally. Why did humans evolve to have periods when fewer than two percent of mammals share our experience of menstrual cycles? Is it really a good use of our limited energy res...

Jun 04, 202140 min

Is my neighbour’s noise harming my health?

As millions more of us move to live in densely populated cities, we almost inevitably face living in closer proximity to our neighbours. Neighbour noise can certainly be a source of annoyance – but could it even be damaging to our health? Increasing evidence suggests that unwanted noise can cause sleep deprivation, distraction and annoyance, as presenter Anand Jagatia finds out. He discovers that noise annoyance has a small but significant impact on our wider health – including our cardiovascula...

May 28, 202128 min

How old are the elements?

You are a star. Literally. You are a carbon-based life form and those atoms of carbon in the molecules that make up your cells were formed by a nuclear fusion reaction at the heart of long dead stars. That goes for the oxygen in your lungs too. And the red blood cells that carry that oxygen to your tissues? They contain haemoglobin, and nestled at the heart of each molecule is an element (iron) formed by a supernova - the fiery explosion at the death of a star. Your body is a walking, thinking m...

May 21, 202137 min

Could we turn poisonous plants into edible crops?

There are over 400,000 species of plant on earth, they’re on every continent including Antarctica. But humans only regularly eat about 200 species globally, with the vast majority of our nutrition coming from just three species. Many of the fruits, leaves and tubers that other plants grow are packed full of toxins that are poisonous to us, and would make us very ill if we ate them. But could we take out the poisons and create new, edible crops? That’s what CrowdScience listener Marija wants to k...

May 14, 202128 min

Why is learning stuff harder as you get older?

Have you taken classes to learn a new sport or musical instrument or a language? It’s hard work! Why is it that as children we effortlessly absorb new skills and we don’t as adults? That’s what 50-something listener Gary Grief wondered about playing guitar. Do you need to play more frequently as an adult to attain the same level of expertise? Does the 10,000-hours theory still apply? Presenter and budding tabla-player Anand Jagatia embarks on a musical journey to discover what neuroscience can t...

May 07, 202136 min

Why are seeds such different sizes?

When eating a blackberry one day, CrowdScience listener Charles got a tiny seed stuck in his teeth. That got him wondering: why are seeds the size they are? Why does a blackberry have dozens of tiny pips, while a peach has one huge stone right in the middle? Plant seeds have been around for hundreds of millions of years, so they’ve had plenty of time to shapeshift into wildly different forms: from dust-like orchid seeds to giant coconuts. This evolution has been a long and intricate dance with w...

Apr 30, 202134 min

What can we learn from wastewater?

Most of us don’t like to dwell on our toilet habits, but this week Crowdscience has gone down the drain to discover what wastewater can tell us about our health. It’s been more than a year since scientists across the globe started to track the spread of Covid-19, with help from home test results and hospital data. Marnie Chesterton investigates the latest tool in their arsenal: sewage. Listener Kevin has heard how human waste can be monitored to check for virus levels, and wants to know if it ca...

Apr 23, 202138 min

Why does grief leave me feeling this way?

Grief is universal. It is something almost all of us will go through at some point. And it is something that the people we love will experience when we die. Grief can be all consuming, it can make everyday tasks like getting out of bed, feel impossible. Which makes listener Oliver from Australia wonder - what is the point? It doesn’t bring what we lost, back. Why have we evolved to be so affected by loss? Be it the death of a loved one, the end of a relationship or the loss of a job. Does it ser...

Apr 16, 202137 min

Why do we gossip?

Gossip often has negative connotations, but does it get a bad rap? Might it serve a useful function and should we think of gossiping as an advanced social skill rather than a personality defect? CrowdScience listener Jayogi thinks it might be useful, and has asked CrowdScience to dig into the reasons why we find it so hard to resist salacious stories. Presenter Datshiane Navanayagam meets a scientist who views gossip as a key evolutionary adaption - as humans started to live in bigger cooperativ...

Apr 09, 202137 min

If a tree falls in a forest does it make a sound?

If a tree falls in a forest, and no-one is there to hear it, does it make a sound? This is an age-old debate that listener Richard and his family have been arguing about for years. Can CrowdScience settle it once and for all? Caroline Steel speaks to experts in hearing, biology, philosophy, physics and sound design, which takes her to some unexpected places. Professor Stefan Bleek is an expert in psychoacoustics who says that sounds only exist in our heads. Dr Eleanor Knox and Dr Bryan Roberts a...

Apr 02, 202140 min

Do animals use medicine?

Animals experience all the colds, stomach pains, headaches, parasites, and general illnesses that humans do. But unlike us, animals can’t just grab a painkiller off the shelf at the supermarket to cure it. They don’t have a pharmacy to browse… or at least, not the sort that we’d recognise. Listener Andrew Chen got in touch to ask whether animals use any kind of medicine themselves. After all, our own drugs largely come from the plants and minerals found in wild habitats. So perhaps animals thems...

Mar 26, 202130 min