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We take your questions about life, Earth and the universe to researchers hunting for answers at the frontiers of knowledge.
October 15, 2021
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 neurological injuries and neurodegenerative disorders. Some labs have actually started 3D printing stem cells into sections of brain tissue in order to study specific interactions in the brain. Human brain organoids offer another way to study brain development and diseases from autism to the Zika virus. So, might stem cell research one day lead to a fully-grown human brain, or is that resolutely in the realm of science fiction? If something resembling our brains is on the horizon, is there any chance that it could actually become conscious? And how would we even know if it was? Host Marnie Chesterton takes a peek inside the human brain and speaks with leading scientists in the field, including a philosopher and ethicist who talks about the benefits – and potential pitfalls – of growing human brain models. Along the way, we'll pull apart the science from what still remains (at least for now) fiction. Presented by Marnie Chesterton Produced by Sam Baker for BBC World Service
October 8, 2021
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 important than others in maintaining the balance of life on earth. Is there anything that could go extinct without having knock-on effects? CrowdScience heads to the Hawaiian mountains, a snail diversity hotspot, to discover the deep value of snails to native ecosystems there. Researchers and conservationists are working together to protect these highly endangered snails, and their natural habitats, from multiple threats. We hear why all snails – even the ones munching Alexandre’s petunias – have their role to play in the natural world, and get to grips with cascading extinctions: how the loss of a single species can trigger unpredictable effects on a whole ecosystem. With contributions from Imogen Cavadino, Dr Norine Yeung, Dr Kenneth Hayes, Dr David Sischo, Jan Kealoha, and Professor Ian Donohue. Presented by Marnie Chesterton Produced by Cathy Edwards for the BBC World Service [Image credit: Getty Images]
October 1, 2021
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 same threats again? Presenter Marnie Chesterton sets out to investigate the inner workings of plants and trees, discovering that plants not only have a sophisticated immune system, but that they can use that immune system to warn their neighbours of an attack. Some researchers are also investigating how we can help plants, especially crops, have better immune systems – whether that’s by vaccination or by editing their genes to make their immune systems more efficient. But some plants, like trees, live for a really long time. How long can they remember any attacks for? Can they pass any of those memories on to their offspring? Crowdscience visits one experimental forest where they are simulating the future CO2 levels of 2050 to understand how trees will react to climate change. Featuring: Professor Jurriaan Ton, University of Sheffield Professor Xinnian Dong, Duke University Dr Estrella Luna-Diez, University of Birmingham Peter Miles, F.A.C.E. Facility Technician, University of Birmingham Presented by Marnie Chesterton and Produced by Hannah Fisher for the BBC World Service. Photo credit: Getty Images
September 24, 2021
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 hears that different species have developed different strategies for doing this based on all sorts of things, from where they’re located to how big they are to what kind of insects are around to pollinate them. The famously stinky Titan Arum, or corpse flower, for example, blooms for a single day once every decade or so before collapsing on itself and becoming dormant again. This gives it the best chance of attracting carrion beetles in the steamy Sumatran jungle. But other plants open their petals much more regularly, which is a process regulated by a clever internal clock that can sense daylight and night. It’s even possible to trick some of them into producing flowers out of season. Cold is also a vital step for some brassicas and trees, and scientists are starting to understand the genes involved. But as climate change makes winters in parts of the world warmer and shorter, there are worrying knock on effects for our food supply. Produced by Marijke Peters for BBC World Service. Featuring: Guy Barter, RHS Professor Judy Jernstedt, UC Davis Professor Dame Caroline Dean, John Innes Centre Professor Ove Nilsson, Umea Plant Science Centre (Photo credit: Getty Images)
September 17, 2021
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! The problem is that eyes weren’t ever designed - they were cobbled together over millions and millions of years, formed gradually by the tweaks and adaptations of evolution. How do you get from the basic detection of light to the wonderful complexity - and diversity – of visual systems we find throughout the animal kingdom? CrowdScience sent Marnie Chesterton on an 800 million year journey to trace how the different elements that make up the human eye gradually came into being; from the emergence of the first light-sensitive proteins to crude eye-cups, from deep sea creatures with simple pinhole eyes to the first light-focusing lenses, all the way to the technicolour detail of the present day. Produced by Ilan Goodman for the BBC World Service. With contributions from: Dr Adam Rutherford, Dr Megan Porter, Professor Dan Nilsson, Dr Samantha Strong (Photo Credit: Getty Images)
September 10, 2021
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 traditional power lines difficult and costly, could wireless electricity help connect those communities who are without mains power? CrowdScience presenter Melanie Brown beams to reporters around the world who visit scientists now using state of the art technology to reimagine Tesla’s dream. Alex Lathbridge is in Ghana and after meeting listener George he gently doorsteps a local electrical engineering lecturer to find out how electricity can ‘jump’ between two coils. Reporter Stacy Knott visits start-up company EMROD in New Zealand who are developing ‘beamable’ electricity. She hears an electric guitar being powered from 36 metres away with no wires and finds out how they are using lasers to make sure they don’t harm any wildlife that might wander into the beam. We then hear how wireless electricity could help fulfil the power demands of a growing electric vehicle market. Reporter John Ryan visits the town of Wenatchee where it has been electrifying its’ bus fleet and putting wireless chargers into the tarmac at bus-stops so that the busses can trickle charge as passengers get on and off. Finally, we ask whether one day, the tangled knot of wires spilling out of our electronic devices will be but a thing of the past. Presented and Produced by Melanie Brown with additional reporting from; Alex Lathbridge, John Ryan and Stacey Knott With contributions from; Prof. Bernard Carlson, Dr Samuel Afoakwa, Ray Simkin, Greg Kushnier, Andy Daga and Richard DeRock (Photo credit: Getty Images)
September 3, 2021
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 Lake City in the USA, who wonders if there’s anything we can do about light pollution. Of course, we could simply turn out all the lights, but that’s unrealistic. So what are smarter ways of lighting our communities to preserve our view of the cosmos? Increasingly worried by the effect of artificial lighting on the ability to observe stars, astronomer Dr Jason Pun set up a series of monitoring stations to continuously measure ‘sky glow’. By comparing sky glow across the world, he wants to figure out which approaches work best. One community taking an active approach is the South Downs National Park in South East England, one of a number of Dark Sky Reserves around the word. We visit the park and speak to the Dark Skies Officer there, to find out how people are coming together to turn down their lights and keep the night dark. And it’s not just stargazing that’s threatened by light pollution. Artificial light at night disrupts the circadian rhythms of wildlife. We visit a project in rural Germany looking into the benefits of dark-sky-friendly lighting on insect populations there. With contributions from Dr Jason Pun, Paulina Villalobos, Dan Oakley, Doug Jones, Dr Sibylle Schroer and Sophia Dehn. Presented by Anand Jagatia with additional reporting by Felix Franz Produced by Cathy Edwards [Image credit: Getty Images]
August 27, 2021
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 back into our pre-history, to our ancient human ancestors? No interruption for them from an unwanted work email, however perhaps a ravenous lion gave them more reason for those night time worries. CrowdScience listener Tom asks our sleep deprived presenter Datshiane Navanayagam to investigate how our sleep has changed over history and pre-history. She talks to Professor Russell Foster, Head of the Sleep and Circadian Neuroscience Institute at the University of Oxford and Neanderthal expert Dr Rebecca Wragg Sykes about slumber habits in days of yore, and in doing so, she uncovers some top tips from our ancestors that may give us all a better nights rest. Presented by Datshiane Navanayagam and Produced by Alexandra Feachem (Woman sitting in bed and yawning. Credit: JGI/Jamie Grill/Getty Images)
August 21, 2021
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. Is this really the pinnacle of evolution? Marnie Chesterton makes the case for the largest, fastest-growing organ, hiding in plain site on our body. Tissue Engineer Professor Sheila MacNeil from Sheffield University explains how skin manages to be breathable yet waterproof; flexible yet stronger than steel; sensitive to touch but protective against pollution and damaging UV. Skin biologist Dr Christina Philippeos from King’s College London explains how our bodies make a scar. Professor Muzlifah Haniffa has developed an atlas of the human skin – a tool to help researchers unravel the mysteries of how different skin cells interact. This atlas should help treat skin diseases in the future. Over in Tanzania’s Regional Dermatology Training Centre in Moshi, Dr Daudi Mavura talks us through a rare but devastating skin disorder called Xeroderma Pigmentosum, or XP. For children with XP, sunlight is dangerous because a mutation in the skin’s DNA repair mechanism means that UV rays can cause lesions and tumours. Our epidermis is already multifunctional but over at Ben May Department of Cancer Research at the University of Chicago, Professor Xaioyang Wu and colleagues are looking at how much more skin could do. Personalised skin grafts may provide living drug patches to help people manage their disease, addiction or even weight. With thanks to Dr Lynne MacTavish from Mankwe Wildlife Reserve in South Africa for describing a rhino’s skin. Produced and presented by Marnie Chesterton. [Image: Young and Old, dry skin Credit: Eric A. Nelson/Getty Images]
August 13, 2021
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 farm on the island of Orkney to predict periods of high winds, so that excess energy can be turned into hydrogen and stored, then converted back to electricity when there’s greater demand. Digital mirrors are also playing a major role in optimising performance, and scientists say cloud-based “twins” of physical assets like turbines can improve yield by up to 20%, allowing engineers to identify problems via computer without ever having to be on site. Marnie visits an intelligent building in London’s financial district where sensors control everything from air-conditioning to lighting, and machine learning means the building knows which staff will be on which floor at any given time, switching off lifts that are not in use and adjusting ventilation to save on power. Its designer says incorporating this kind of digital technology will help companies achieve net zero more quickly. And in India, more than half the population are involved in agriculture, but the sector is plagued by inefficiency and waste. Tech start-ups have realised there’s potential for growth, and are using drones to monitor crop production and spraying, giving farmers apps which help them decide when and where to fertilise their fields. Produced by Marijke Peters for BBC World Service. Featuring: Professor Srinivasan Keshav, University of Cambridge Matthew Marson, Arcadis Group [Image Credit: Getty Images]
August 6, 2021
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 explore difficult issues like death, grief and loss? Alex Lathbridge and Anand Jagatia look at the evidence and play some games along the way, speaking to psychologists, doctors and game designers about the power of video games to change us - for better or worse. With Adrian Hon, Professor Andrew Przybylski, Professor Pete Etchells, Professor Henrietta Bowden-Jones and Dr Sabine Harrer
July 30, 2021
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 investigate if food containers really need to be cleaned before we put them in recycling bins, or if that just wastes water. Recycling processes differ all over the world, so we hear from reporter Chhavi Sachdev in Mumbai, India, who follows her plastic waste to find out how plastic sorting and recycling is a whole economy of its own. But new technologies have meant that biodegradable and bioderived plastics are starting to appear in our packaging, and one Crowdscience listener wants to know which is better for the environment – traditional plastic that has been recycled, or bioplastic and compostable alternatives? And looking to the future, could we ever recycle our plastic waste at home and use 3D printers to make useful things out of our own waste? Marnie Chesterton delves into these questions with Circular Economy Project Manager Dr Rhiannon Hunt of Manchester Metropolitan University, to discover the details of recycling and unearth how we can make our own recycling as efficient as possible. With Dave Atkins, reporter Chhavi Sachdev and Dr Rhiannon Hunt. Presented by Marnie Chesterton and Produced by Hannah Fisher for the BBC World Service. [Image credit; Getty Images]
July 23, 2021
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 brain when she empathises. Studies suggest around 1 percent of the general population exhibit traits associated with psychopathy and that rises to 3-4 percent in the world of business. But is this really the case? Why is there so much stigma associated with psychopathy and do psychopaths even exist or is it just a convenient term to label those whose emotional range sits outside of the “norm”? Presented by Marnie Chesterton and produced by Caroline Steel for the BBC World Service. Guests: Julia Shaw Jim Fallon Valeria Gazzola Kalliopi Ioumpa [Image credit: Getty Images]
July 16, 2021
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 also fascinated in how string becomes jumbled up and one man has even won an IgNobel award for his work in this field. Doug E Smith discovered that if you put a piece of string in a box then spin it around, its length, thickness and how long you shake the box for, all determine whether it will tie itself up. Not only that, the more the string becomes twisted, the more likely it is to cross over itself and become impossible to untangle. While tangles might be annoying in hair or cables, they’re also a fundamental part of human life. Our DNA is constantly folding itself to fit inside tiny spaces – there are two metres of the stuff inside every cell, where it’s packed down tightly, before it must untangle and duplicate for those cells to divide. It does this with the help of specific enzymes, and when the process goes wrong it leads to cell death. But scientists are also studying molecular tangles that might benefit us humans, and creating nano-sized knots that can be turned into nets or meshes with incredible properties. Producer: Ilan Goodman Presenter: Marnie Chesterton
July 9, 2021
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 our whole system – body and brain – works better when we’re walking, compared to standing still. We’re probably set up this way because of our evolutionary history: hunting and gathering needed us to be ‘cognitively engaged endurance athletes’. We stop for a break.. but is it true that we shouldn’t sit down to rest during a walk? Our listener Sarah is a keen hillwalker but likes to take the weight off her feet every now and again. Her hillwalking friends disapprove, saying she should rest on her feet. Is this a myth CrowdScience can bust? And finally a question from listener Matteo: is walking or running better for your health? Numerous studies show significant benefits to both forms of exercise, but in the end, the best kind of exercise is the one you’re motivated to do. With Caroline Williams, Dr François-Xavier Li, Professor Dick Greene and Professor Duck-Chul Lee.
July 2, 2021
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 activity for many people stuck in their homes, one listener wants us to find out if eating food whilst watching the TV affects our perception of taste. We then journey to the skies and ask if it is true that food tastes blander on aeroplanes, what does that mean for astronauts’ mealtimes? Back on earth, Marnie explores whether humans are the only animals that season their food. Tuck in your napkins and prepare to feast on a smorgasbord of scientific snacks. Presented by Marnie Chesterton and Produced by Melanie Brown and Hannah Fisher for the BBC World Service. Guests: Professor Charles Spence Dr Kristine Beaulieu Mr. Takashi Funahashi Ruben Meerman Chef Jozef Youseff
June 25, 2021
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 Annabel, who wonders why things other people love to sniff, she finds disgusting. Anand Jagatia investigates the science of smell, gets up close to the world’s smelliest plant and finds out if smell training can help those with long-term issues after Covid. Contributors Ellie Byondin, supervisor of the Princess of Wales Conservatory at London’s Kew Gardens Thomas Hummel, University of Dresden Carl Philpott, from the UK’s Norwich Medical School Sissel Tolaas, artist and smell historian based in Berlin Noam Sobel, Weizmann institute of science Presented by Anand Jagatia and Produced by Marijke Peters for the BBC World Service
June 18, 2021
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 the answer have any implications for the future of Earth? Could the atmosphere eventually run out? Contributors: Anuradha TK, former project director at ISRO Matt Genge, geologist at Imperial College London Jon Larsen, researcher at the University of Oslo Anjali Tripathi, astrophysicist Ethan Seigel, journalist and astrophysicist Presented by Marnie Chesterton. Produced by Caroline Steel for the BBC World Service. [Image: Earth on scales. Credit: Getty Images]
June 11, 2021
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 because it can contribute to diabetes, heart disease and obesity. But that’s tricky when you consider it’s now in everything from salad dressings, to savoury sauces. Manufacturers have been promoting sugar alternatives for decades but recreating the unique taste and feel of it in the mouth are a challenge. Marnie Chesterton gets to try a brand new innovation – a so-called ‘rare’ sugar that has 70 percent of the sweetness but almost none of the calories. In nature, allulose is found in figs, but one producer has discovered a way to make it in the lab. Does it taste as good as it claims? Whilst switching to alternative sugars and sweeteners may reduce the calories, some researchers claim that tasting sweetness, wherever it comes from, can disrupt the body’s mechanism for regulating blood-sugar levels, increasing the risk for conditions like diabetes. Presented by Marnie Chesterton and produced by Marijke Peters for the BBC World Service
June 4, 2021
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 reserves? What can the little Egyptian spiny mouse teach us about PMS symptoms? We hear why periods may reduce the number of faulty embryos that implant and how more menstrual cycles may even increase our chances of developing certain types of cancer. Finally, as the number of periods a woman has over the course of her life has more than quadrupled since the pre-industrial era, Marnie asks: Do we really still need to have them? Contributors: Dr Nadia Bellofiore, Hudson Institute of Medical Research at Monash University Dr Deena Emera, Buck Institute Lameck Kiula, Jambo for Development Sally King, Menstrual Matters & King's College London Dr Diana Mansour, New Croft Centre & Newcastle University Presented by Marnie Chesterton Produced by Sam Baker and Melanie Brown for the BBC World Service
© (C) BBC 2021