CrowdScience

CrowdScience listeners David and Tatiana have long been captivated by an unusual dinner table discussion: the peculiar change they’ve noticed over the past 16 years in the sunlight streaming through their bedroom window in Ostend, Belgium. They’re convinced that the room has not only become sunnier but that the actual angle of sunlight has shifted.

Intrigued by their observations, we head to Ostend. Our mission: to investigate three of their theories, enlisting expert help along the way.

Theory 1 – A celestial anomaly? René Oudmaijer at the Royal Observatory of Belgium considers whether our shifting position in the solar system might explain the change.

Theory 2 – Movement in the Earth’s crust? Alejandra Tovar from the Geological Survey of Belgium examines tectonic data to see if the Earth’s crust is moving enough to alter the angle of sunlight.

Theory 3 – Subsidence? Structural engineer Kath Hannigan helps us inspect the building for signs that it may be sinking or twisting.

And we explore one final theory of our own, enlisting memory expert Julia Shaw to examine whether it could all be a trick of the mind. Will the team crack the case?

Presenter: Caroline Steel Producer: Harrison Lewis Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Studio Manager: Sarah Hockley

(Photo: CrowdScience listeners David and Tatiana standing in front of a window in their house)

Fungi are a mysterious and understudied life form. And to add to the intrigue, some of them actually glow in the dark. This phenomenon has sparked CrowdScience listener Derek's curiosity, and he's asked us to investigate.

Presenter Caroline Steel gets on the case. This is just one example of the natural wonder that is bioluminescence – living organisms that glow. How do they produce their light, and is there any reason for it? Caroline visits a bioluminescent bay in Puerto Rico, and Dr Brenda Soler-Figueroa explains what makes it sparkle.

But it turns out there are many different explanations for why living things glow. Fungi, which listener Derek is particularly interested in, are neither plants nor animals, but an entirely different kingdom of life that we know much less about. Professor Katie Field takes on the task of trying to grow us some bioluminescent mushrooms, while Prof Cassius Stevani explains how – and importantly, why – they glow.

And finally – could we ever harness the power of bioluminescence to our advantage in the future?

Presenter: Caroline Steel Producer: Hannah Fisher Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Studio Manager: Neva Missirian

(Photo: Omphalotus nidiformis, or ghost fungus, Penrose, NSW, Australia Credit: Louise Docker Sydney Australia via Getty Images)

Can learning new languages make us forget our mother tongue? CrowdScience listener Nakombe in Cameroon is concerned that his first language, Balue, is slipping from his grasp. He has learned multiple languages through his life, but Balue is the language of his family and home. It’s central to his identity and sense of belonging. So why does it seem to be fading from him, and what can he do to get it back?

We search for answers, investigating what happens in our brains when we struggle to recall languages, as well as the social and economic factors that lead to language loss. Presenter Anand Jagatia asks Michael Anderson from the University of Cambridge, an expert on memory and forgetting, whether forgotten languages disappear from our brain, or just become difficult to access. Linguist Monika Schmid from the University of York takes us through the phenomenon of first language attrition, and has words of reassurance and advice for Nakombe and others in his situation.

And we meet Larry Kimura from the University of Hawai’i at Hilo, a pioneer of Hawaiian language revitalization, and Gabriela Pérez Báez, an expert in indigenous languages and language revitalization at the University of Oregon. They explain why languages around the world become threatened, and how to keep them alive.

Presenter: Anand Jagatia Producer: Margaret Sessa Hawkins Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Managers: Sarah Hockley and Omera Ahamed

(Photo: Diccionario, Argentina Credit: PonyWang via Getty Images)

While there is a myriad of deodorants, shower gels and perfumes helping us stay fresh and fragrant today, that hasn’t always been the case. How did humans stay clean in the past, or did they not care so much? And is there an evolutionary reason for human body odour in the first place?

These are questions that CrowdScience listener Sarah has pondered on trips in her camper van, when she wants to keep clean, but washing isn’t always convenient.

In search of answers, presenter Anand Jagatia delves into the sweaty details: where body odour comes from, why some people's armpits don't smell, and whether this heady stink serves any purpose. Could our natural odour really help to attract a partner, or is it just a smelly bacterial by-product?

Anand explores the intriguing mystery of human pheromones, and hears how for hundreds of years, Europeans were terrified of washing.

Contributors: Dr Madalyn Nguyen, Dermatologist Dr Kara Hoover, Biological Anthropologist, University of Alaska Fairbanks Katherine Ashenburg, author, The Dirt on Clean: An Unsanitized History Dr Tristram Wyatt, Department of Biology, University of Oxford

Presenter: Anand Jagatia Producer: Sophie Eastaugh Production co-ordinator: Ishmael Soriano Editor: Cathy Edwards Sound engineer: Emma Harth

(Photo: Girl sweating smelly armpit, Taiwan Credit: PonyWang via Getty Images)

2024 is the biggest election year in history. From Taiwan to India, the USA to Ghana, by the end of the year almost half of the world’s population will have had the chance to choose who governs them. But there are a huge number of possible voting systems – and listener James wants CrowdScience to find out which is the fairest. To do so, we create a fictional country called CrowdLand to try out different electoral systems. Presenter Caroline Steel consults mathematician David McCune and political scientists Eric Linhart and Simon Hix, and we hear from listeners around the world about how they vote in their respective countries. Can we find the perfect voting system for CrowdLand? Contributors: Prof David McCune, William Jewell College, USA Prof Eric Linhart, University of Technology Chemnitz, Germany Prof Simon Hix, European University Institute, Italy Actors: Charlotte Bloomsbury Ross Virgo Presenter: Caroline Steel Producer: Florian Bohr Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Donald MacDonald

(Image: Hand of a person casting a vote into the ballot box during elections, Thailand Credit: boonchai wedmakawand via Getty Images)

With huge heads on top of spindly stalks, how do sunflowers defy gravity to stay standing? That was a question sent to CrowdScience by listener Frank, whose curiosity was piqued by the towering sunflowers on his neighbour’s deck. They stay up not only when the weather is fine, but, even more impressively, during strong winds. Could this feat of strength, flexibility and balance inspire the construction of tall buildings?

It's a question that takes presenter Anand Jagatia to a sunflower festival in England, to see how the sunflower’s long evolutionary lineage has honed its structure. And from tall flowers to tall buildings, we turn to structural engineers, asking how these concepts factor into the design of the world’s tallest skyscrapers. Can ideas drawn from sunflowers or other natural structures help buildings withstand wind, or even storm surges?

Contributors: Stuart Beare, partner and grower at Tulley’s Farm Roland Ennos, Visiting Professor in Biological Studies, University of Hull Sigrid Adriaenssen, Professor of Civil and Environmental Engineering, Princeton University Koichi Takada, founder of Koichi Takada Architects

Presenter: Anand Jagatia Producer: Tom Bonnett Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Bob Nettles

(Image: Tall Sunflower blooming in a field, Melbourne, Victoria, Australia Credit: Naomi Rahim via Getty Images)

The Moon and Earth are drifting gradually further apart. Every year the gap between them increases by a few centimetres. We know that the Moon’s gravity has an important effect on Earth - from controlling the tides to affecting the planet’s rotation - but slowly, imperceptibly, over billions of years, that influence will diminish as the Moon moves away. For CrowdScience listener Tony in the UK that idea poses another question. What if we were to look back in time? What effects did the Moon have when it was closer to Earth? Would it counteract the planet’s gravity more so that, at the time of the dinosaurs, a Brontosaurus would weigh a little less that it would if it existed now? It’s an intriguing question. And, given that it involves both the Moon AND dinosaurs, it’s one that’s got presenter Anand Jagatia really excited!

Anand begins his journey on Brighton beach on the South coast of the UK. He’s there to watch the full Moon rise - and get a few insights on Tony’s question - from astronomer Darren Baskill and astrophotographer (and cellist) Ivana Perenic.

Anand talks to Darren about the influence of the Moon’s gravity on Earth today. As they stand on the beach, with the sea lapping at their feet, they can certainly see its effect on the ocean tides. But did you know that the Moon also causes tides on the land as well? Every time it’s overhead the ground you’re standing on is higher by a few centimetres.

Professor Neil Comins, author of the book What If the Moon Didn’t Exist, explains why the tides are the reason the Moon is moving away from Earth – and it has been ever since it was first formed.

And how was it formed anyhow? We turn back time with Prof. Sara Russell from the Natural History Museum in London to discover one of the most dramatic events in the early history of our solar system... when two worlds collided.

And, of course, it helps to know what a dinosaur weighed in the first place. Anand turns to paleontologist Nicolas Campione, who’s been puzzling over the most accurate way to calculate the bulk of a Brontosaurus.

Contributors: Dr. Darren Baskill, Astronomer, University of Sussex, UK Ivana Perenic, Astrophotographer Dr. Nicolas Campione, Paleontologist, University of New England, Australia Prof. Sara Russell, Cosmic Mineralogist, Natural History Museum, UK Prof. Neil Comins, Astronomer, University of Maine, USA

Presenter: Anand Jagatia Producer: Jeremy Grange Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Jackie Margerum

(Image: Tyrannosaurus Rex and Spinosaurus in front of the moon - stock photo Credit: MR1805via Getty Images)

18 is the age of majority, or maturity, in most countries around the world. Depending where you live, it might be when you can vote, buy alcohol, or get married. But what's so special about 18 that makes it the beginning of adulthood? CrowdScience listener Lynda didn't feel very mature back then. She recalls a difficult decision that made her wonder what science has to say about when we’re truly grown up. How developed are we, physically, mentally and emotionally, by the age of 18? And how much does this differ between people, or from culture to culture? Presenter Caroline Steel digs around for answers with the aid of neuroscientist Sarah-Jayne Blakemore, biological anthropologist Barry Bogin, and cultural anthropologist Bonnie Hewlett. And even some teenagers. Contributors: Barry Bogin, Emeritus Professor of Biological Anthropology, Loughborough University Sarah-Jayne Blakemore - Professor of Psychology and Cognitive Neuroscience at the University of Cambridge Professor Bonnie Hewlett - Associate Professor, Cultural Anthropology, WSU Vancouver

Presenter: Caroline Steel Producer: Richard Walker Editor: Cathy Edwards Production Co-Ordinator: Ishmael Soriano Studio Manager: Neva Missirian

An apex predator is a killer. Usually large and terrifying, they enjoy the privilege of life at the top of a food chain. Nothing will eat them, leaving them free to wreak carnage on more vulnerable creatures.

In biology, it’s a term normally reserved for animals like polar bears, tigers and wolves. But CrowdScience listener Eoin wonders whether there’s a non-animal candidate for apex predator: the car. After all, worldwide, more than 1.5 million humans die on the roads each year, while pollution from traffic kills millions more. And that’s just the impact on us. What are cars doing to all the other species on this planet?

Host Anand Jagatia hits the road to investigate. En route, we’ll be picking up some scientists to help answer the question. It turns out to be so much more than a question of roadkill: cars, and the infrastructure built to support them, are destroying animals in ways science is only now revealing.

How did the wildlife cross the road? We go verge-side to test four different approaches. And we hear how cars manage to kill, not just on the roadside, but, in the case of some salmon species, from many miles away. Gathering as much evidence as possible, we pass judgement on whether the car truly is an apex predator.

Contributors: Samantha Helle - Conservation Biologist and PhD student, University of Wisconsin–Madison Paul Donald – Senior Scientist, BirdLife International and Honorary Research Fellow, University of Cambridge Zhenyu Tian – Environmental Chemist and Assistant Professor, Northeastern University

Presenter: Anand Jagatia Producer: Marnie Chesterton Reporter: Camilla Mota Editor: Cathy Edwards Studio manager: Donald MacDonald and Giles Aspen Production co-ordinator: Ishmael Soriano

(Image: Illustration of a deer in front of a car - stock illustration Credit: JSCIEPRO/SCIENCE PHOTO LIBRARY via Getty Images)

Many of us experience an inner voice: we silently talk to ourselves as we go about our daily lives. CrowdScience listener Fredrick has been wondering about the science behind this interior dialogue. We hear from psychologists researching our inner voice and discover that it’s something that begins in early childhood. Presenter Caroline Steel meets Russell Hurlburt, a pioneering scientist who devised a method of researching this - and volunteers to monitor her own inner speech to figure out what’s going on in her mind. She discovers that speech is just part of what’s going on in our heads, much of our inner world in fact doesn’t involve language at all but includes images, sensations and feelings. Caroline talks to psychologist Charles Fernyhough, who explains one theory for how we develop an interior dialogue as young children: first speaking out loud to ourselves and then learning to keep that conversation going silently. No one really knows how this evolved, but keeping our thoughts quiet may have been a way of staying safe from predators and enemies. Using MRI scanning, Charles and Russell have peered inside people’s brains to understand this interior voice and found something surprising: inner dialogue appears to have more in common with listening than with speaking.

Caroline also has an encounter with a robot that has been programmed to dialogue with itself. Which leads us to some deep questions: is our inner voice part of what makes us human, and if so, what are the consequences of robots developing this ability? Scientist Arianna Pipitone describes it as a step towards artificial consciousness.

Featuring: Professor Charles Fernyhough, University of Durham, UK Professor Russell Hurlburt, University of Nevada, Las Vegas, USA Dr Arianna Pipitone, University of Palermo, Italy Presenter: Caroline Steel Producer: Jo Glanville Editor: Cathy Edwards Sound design: Julian Wharton Studio manager: Donald MacDonald Production co-ordinator: Ishmael Soriano

(Image: Mixed Race boy looking up Credit: Jose Luis Pelaez Inc via Getty Images)

It would be quite a superpower to regrow entire body parts. CrowdScience listener Kelly started pondering this after a discussion with her friend on whether human tongues could regrow. Finding out that they couldn't, she asked us to investigate the extent of human regenerative abilities.

Presenter Alex Lathbridge travels to Vienna, a hotbed of research in this area. He meets an animal with much better powers of regeneration than humans - the axolotl. In Elly Tanaka’s lab he finds out how she studies their incredible abilities – and shows off his new axolotl tattoo.

Why can these sweet-looking salamanders regrow entire limbs while we can’t even regrow our tongues? Palaeontologist Nadia Fröbisch has looked into the evolutionary origins of regeneration, and it goes a lot further back than you might think.

And in fact, even humans are constantly regenerating, by renewing the building blocks of our bodies: cells. New cells grow and replace old ones all the time – although, in some parts of the body, we do keep hold of the same cells throughout our lives.

However, cell turnover isn’t the same as regrowing entire organs or limbs. But can we grow new body parts in the lab instead? We meet Sasha Mendjan, who creates heart organoids using our cells’ innate ability to self-organise. How far off are we from implanting organs, grown from a patient’s stem cells, back into the human body?

Contributors: Dr Elly Tanaka, Institute of Molecular Biotechnology (IMBA) Prof Martin Hetzer, Institute of Science and Technology Austria (ISTA) Prof Nadia Fröbisch, Natural History Museum Berlin Dr Sasha Mendjan, Institute of Molecular Biotechnology (IMBA)

Presenter: Alex Lathbridge Producer: Florian Bohr Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Bob Nettles

Why do we have two eyes? Two ears? Two arms and two legs? Why is one side of the human body – externally at least – pretty much a mirror image of the other side?

CrowdScience listener Kevin from Trinidad and Tobago is intrigued. He wants to know why human beings – and indeed most animals - have a line of symmetry in their bodies. Yet, beyond their flowers and fruits, plants don’t seem to have any obvious symmetry. It seems that they can branch in any direction.

Anand Jagatia sets out to find out why the animal kingdom settled on bilateral symmetry as the ideal body plan. And it takes him into the deep oceans of 570 million years ago. Paleobiologist Dr. Frankie Dunn is his guide to a time when animal life was experimenting with all sorts of different body plans and symmetries.

Frankie shows Anand a fossil of the animals which changed everything. When creatures with bilateral symmetry emerged they began to re-engineer their environment, outcompeting everything else and dooming them to extinction.

Well... nearly everything else. One very successful group of animals which have an utterly different symmetry are the echinoderms. That includes animals with pentaradial - or five-fold - symmetry like starfish and sea urchins. And that body shape poses some intriguing questions... like “where’s a starfish’s head?” Dr. Imran Rahman introduces us to the extraordinary, weird world of echinoderms.

To answer the second part of Kevin’s question - why plants don’t seem to have symmetry – Anand turns to botanist Prof. Sophie Nadot. She tells him that there is symmetry in plants... you just have to know where to look! Beyond flowers and fruits, there’s also symmetry in a plants leaves and stem. The overall shape of a plant might start out symmetrical but environmental factors like wind, the direction of the sun and grazing by animals throws it off-kilter.

And, while the human body may be symmetrical on the outside, when you look inside, it’s a very different story. As listener Kevin says, “our internal organs are a bit all over the place!” Prof. Mike Levin studies the mechanisms which control biological asymmetry. He tells Anand why asymmetry is so important... and also why it’s so difficult to achieve consistently.

Contributors: Dr. Frankie Dunn, Oxford University Museum of Natural History, UK Dr. Imran Rahman, Natural History Museum, London, UK Prof. Sophie Nadot, Université Paris-Saclay, France Prof. Mike Levin, Tufts University, Massachusetts, USA

Presenter: Anand Jagatia Producer: Jeremy Grange Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Andrew Garratt

(Image: Orange oakleaf butterfly (Kallima inachus) on tropical flower, Credit: Darrell Gulin/The Image Bank via Getty Images)

It's a simple metal box that moves nearly all of our goods around the world. Designed for uniformity and interchangeability, the shipping container has reshaped global trade and our lives in the nearly 70 years since its creation.

But listener Paul wants to know if these heavy steel containers could be made with lighter materials to cut down on the fuel needed to transport them, especially when they're empty. Could we make shipping containers a more efficient process and reduce the shipping industry’s sizable greenhouse gas emissions?

Host Anand Jagatia travels to Europe's largest port in Rotterdam looking for answers. Speaking to environmental scientists and industry insiders along the way, he takes a look at how the humble container might be modified to once again remake global shipping, from materials, to designs, to how it’s shipped. And thinking outside the box, we explore which innovations might benefit the whole system – from machine learning to new, carbon-free energy sources.

For an industry that’s not always quick to change, we speak with the changemakers trying to disrupt the way 90% of the stuff we buy moves, in hope of a greener future.

Featuring: Maarten van Oosten - Port of Rotterdam Authority Marc Levinson - historian, economist and author Greg Keoleian - School for Environmental Sustainability and Center for Sustainable Systems, University of Michigan Hans Broekhuis - Holland Container Innovations Trine Nielsen, Flexport Tristan Smith - University College London Elianne Wieles – Deep Sea Carriers, Port of Rotterdam

Presenter: Anand Jagatia Producer: Sam Baker Editor: Cathy Edwards Production Coordinator: Ishmael Soriano Studio Manager: Steve Greenwood

(Photo: Port of Rotterdam, Maasvlakte Deep Sea Carrier Area. Credit: Sam Baker, BBC)

When listener Watum heard about the Titan submersible implosion in the news in 2023, a question popped up in his mind: if a machine that we specifically built for this purpose cannot sustain the water pressure of the deep ocean, how do fish survive down there?

In this episode, we travel with marine biologist Alan Jamieson to the second deepest place in our oceans: the Tonga trench. Meanwhile, presenter Caroline Steel speaks to Edie Widder about the creatures that illuminate our oceans, and travels to Copenhagen to take a closer look one of the strangest deep sea creatures and its deep sea adaptations.

But even fish have their limits! Scientist Paul Yancey correctly predicted the deepest point that fish can live, and it all comes down to one particular molecule.

So is there anything living beyond these depths? Well, there is only one way to find out…

Contributors: Prof Alan Jamieson, University of Western Australia Luke Siebermaier, Submersible Team Leader, Inkfish Dr Edie Widder, Ocean Research & Conservation Association Peter Rask Møller, Natural History Museum of Denmark Prof Paul Yancey, Whitman College

Presenter: Caroline Steel Producer: Florian Bohr Editor: Martin Smith & Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Steve Greenwood

(Image: Deep-sea fish - stock photo, Credit: superjoseph via Getty Images)

CrowdScience listener Azeddine from Algeria has had bad handwriting since he was a child. In fact, it was so untidy that, when he later became a chemistry lecturer, his university students complained that they could not read his lecture notes. That was when he decided he had to do something about it. And it got him wondering… why do some of us have very neat handwriting while other people’s is almost unreadable? Why do his sisters all write beautifully when his natural style is quite the opposite? Presenter Alex Lathbridge sets out to answer Azeddine’s question. He explores the different factors which determine how well we write. How much of it is inherited? What part does family and education play? And what is actually going on in our brains when we apply pen to paper? Alex talks to anthropologist Monika Saini of the National Institute of Health and Family Welfare, Delhi, who has analysed writing styles within families and in different regions across India. She tells him about the genetic and cultural factors which seem to influence our handwriting. We also hear from neuroscientist Marieke Longcamp of Aix Marseille Université, France, who uses MRI scanning to find out which parts of our brains are involved when we write by hand. She has looked at what is happening in the brains of people who write in more than one script – for example in French and Arabic, like Azeddine. Another neuroscientist, Karin Harman James, from Indiana University, USA ,has been looking at the link between learning something by writing it down compared to typing it on a tablet or laptop. And Alex meets handwriting tutor Cherrell Avery to find out if it’s possible to improve your writing – even as an adult. Presenter: Alex Lathbridge Producer: Jeremy Grange Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Emma Harth

In many languages across the world, all nouns are classed as either male or female, or sometimes neuter. The English language, however, only signals gender in its pronouns - he, she, it or they. For inanimate objects, gender just crops up in occasional examples like ships or countries, which, for some reason, are deemed female. This lack of gender in English intrigued CrowdScience listener Stuart, since the other languages he knows all highlight whether something is male or female. Did English ever have gender, and if so, where did it go? Presenter Anand Jagatia dives into some Old English texts to uncover the idiosyncrasies of its masculine and feminine nouns, and learns why these gradually fell out of use. But why do other languages assign gender to nouns – male, female, and sometimes many more categories too? And does this affect the way we think?

Contributors: Andrew Dunning, Curator of Medieval Manuscripts, Bodleian Library, Oxford University Rachel Burns, Departmental Lecturer in Old English, Oxford University Suzanne Romaine, Professor of Linguistics, Hawaii Ida Hadjivayanis, Senior Lecturer in Swahili, SOAS University Angeliki Alvanoudi, Sociolinguist, Aristotle University of Thessaloniki Amy Bahulekar, Writer, Mumbai

Presenter: Anand Jagatia Producer: Eloise Stevens Editor: Cathy Edwards Production Coordinator: Ishmael Soriano

Buildings inspire many emotions, like awe, serenity or even dread. CrowdScience listener Siobhan was struck by this as she passed a huge apartment block with tiny windows; it reminded her of a prison. So, she asked us to investigate the feelings that buildings can trigger. Architects have long considered how the effect of buildings on their occupants or passersby: asking whether certain features elicit feelings of wonder or joy... or sadness and fear. And now modern neuroscience has started to interrogate these very questions, too. How much of the way we feel about a building is to do with its intrinsic design, and how much is due to our individual brain chemistry and life experiences? Presenter Caroline Steel talks to designer Thomas Heatherwick about his ideas for improving public spaces; enters a virtual reality simulation in Denmark to learn about the emerging field of ‘neuroarchitecture’; and finds out why people just can’t agree what makes a ‘good’ or ‘bad’ building.

Contributors: Thomas Heatherwick, Heatherwick Studios, London Professor Zakaria Djeberra, University of Aalborg Professor Lars Fich, University of Aalborg Professor Edward Vessel, City College of New York Presenter: Caroline Steel Producer: Richard Walker Editor: Cathy Edwards Production Coordinator: Ishmael Soriano Studio Manager: Duncan Hannant

(Image: Rear view of woman surrounded by old traditional residential buildings and lost in city, Hong Kong, China. Credit: d3sign via Getty Images)

How do you think about the internet? What does the word conjure up? Maybe a cloud? Or the flashing router in the corner of your front room? Or this magic power that connects over 5 billion people on all the continents of this planet? We might not think of it at all, beyond whether we can connect our phones to it.

Another chance to hear one of our favourite episodes, inspired by a question from CrowdScience listener Simon: how much does the internet weigh?

First of all, this means deciding what counts as the internet. If it is purely the electrons that form those TikTok videos and cat memes, then you might be surprised to hear that you could easily lift the internet with your little finger. But presenters Caroline Steel and Marnie Chesterton argue that there might be more, which sends them on a journey.

They meet Andrew Blum, the author of the book Tubes – Behind the Scenes at the Internet, about his journey to trace the physical internet. And enlist vital help from cable-loving analyst Lane Burdette at TeleGeography, who maps the internet.

To find those cables under the oceans, they travel to Porthcurno, once an uninhabited valley in rural Cornwall, now home to the Museum of Global Communications thanks to its status as a hub in the modern map of worldwide communications. With the museum’s Susan Heritage-Tilley, they compare original telegraph cables and modern fibre optics.

The team also head to a remote Canadian post office, so correspondent Meral Jamal can intercept folk picking up their satellite internet receivers, and ask to weigh them. A seemingly innocuous question becomes the quest for everything that connects us... and its weight!

Producer: Marnie Chesterton Presenters: Marnie Chesterton & Caroline Steel Editors: Richard Collings & Cathy Edwards Production Coordinators: Jonathan Harris & Ishmael Soriano Studio Manager: Donald MacDonald

(Image: Blue scales with computer coding terms. Credit: Alengo via Getty Images)

Snakes are often seen as slithery, slimy and scary. But these intriguing non-legged creatures have made CrowdScience listener Okello from Uganda wonder how they move – more specifically, he wants to know how they climb trees so easily, and so fast.

Presenter Caroline Steel meets snake expert Mark O’Shea to investigate the ingenious methods different snakes use to scale a tree trunk, and gets a demonstration from a very agreeable corn snake at a zoo.

Snake movement isn’t just your typical S-shaped slithering: these reptiles move in a remarkably diverse range of ways. Melissa Miller from the University of Florida explains all the range of motion snakes can employ to effectively travel along the ground as well as at height.

Caroline witnesses this in action as we pay a steamy visit to the Everglades National Park in Florida, USA, tracking pythons across the vast swamps there. We find out why understanding these pythons’ movement is vitally important for conserving the local ecosystem.

Contributors: Dr Melissa Miller, Research Assistant Scientist, University of Florida Brandon Welty, Wildlife Biologist, University of Florida Prof Mark O’Shea MBE, Professor of Herpetology, University of Wolverhampton

Presenter: Caroline Steel Producer: Hannah Fisher Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Neva Missirian

The CrowdScience team like a challenge. And listeners Jenny and Kai in the UK have come to us with a big one. They want to know how many flies have ever existed.

Flies first appeared around 270 million years ago, so presenter Caroline Steel prepares herself to calculate a very, very large number indeed. She enlists the help of Dr Erica McAlister, Curator of Flies at the Natural History Museum in London. As Erica introduces her to specimens from the Museum’s collection of over 30 million insects, they start with the basics. Like... how do you define a fly in the first place?

Caroline also explores the incredible diversity of flies… from fast-moving predators like robber flies which catch other insects on the wing to midges which are a vital part of chocolate-production; and from blood-sucking mosquitoes which transmit fatal diseases to the housefly buzzing lazily around a room.

And that leads to another fly-related question. Listener Brendan in Colombia wonders why they always fly in circles around a particular area of his apartment. For an explanation we turn to Prof. Jochen Zeil from the Australian National University who reveals that this apparently aimless behaviour is, in fact, a battle for sex.

And Collin in Barbados has e-mailed to ask how flies and mosquitoes benefit us. He’s had first-hand experience of their negative effects through contracting the disease chikungunya from a mosquito bite so he’s wondering if these insects are anything other than a nuisance. However, passionate fly advocate Erica McAlister is ready with plenty of reasons that we should be extremely grateful for them!

Contributors: Dr Erica McAlister, Natural History Museum, London Dr David Yeates, Director, Australian National Insect Collection Prof. Jochen Zeil, Australian National University Prof. Jo Lines, London School of Hygiene and Tropical Medicine

Presenter: Caroline Steel Producer: Jeremy Grange Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Sarah Hockley

(Image: Close-up of insect on leaf, Kageshwori Manohara, Bagmati Province, Nepal. Credit: Aashish Shrestha via Getty Images)

It’s hard to imagine something as mind-bogglingly small as an atom.

But CrowdScience listener Alan has been attempting to do just that. All things in nature appear to be different and unique; like trees and snowflakes, could it be that no two atoms are ever the same?

Alan isn’t the first person to wonder this. Philosopher and scientist Gottfried Leibnitz had a similar idea in the 17th century; in this episode, philosopher of physics Eleanor Knox helps us unpick the very idea of uniqueness.

And with the help of physicist Andrew Pontzen, presenter Anand Jagatia zooms into the nucleus of an atom in search of answers. Listener Alan has a hunch that the constant movement of electrons means no atom is exactly the same at any given moment in time. Is that hunch right? We discover that the world of tiny subatomic particles is even stranger than it might seem once you get into quantum realms.

Can we pinpoint where uniqueness begins? And if the universe is infinite, is uniqueness even possible?

In the podcast edition of this show, we peer into that expansive universe, as we discover that the quantum world of hydrogen - the tiniest and most abundant of all atoms - allows us to observe galaxies far, far away. Featuring: Dr Eleanor Knox – King’s College London Prof Andrew Pontzen – University College London Dr Sarah Blyth – University of Cape Town Dr Lucia Marchetti – University of Cape Town

Presented by Anand Jagatia Produced by Florian Bohr Editor: Cathy Edwards Production Coordinators: Ishmael Soriano and Liz Tuohy Studio Manager: Emma Harth

(Photo: Twelve snow crystals photographed under a microscope, circa 1935. Credit: Herbert/Archive Photos/Getty Images)

Listener Julie lives close to the coast in New Zealand and wants to know why the water that washes up on the beach isn't fresh. How exactly does all that salt get into the world's oceans?

In India, a country where salt became symbolic of much more than well-seasoned food, host Chhavi Sachdev visits coastal salt farms and a research institute dedicated to studying all things saline, to better understand our relationship with salty seas.

The team also ventures to a very briny lake on the other side of the globe in Salt Lake City, Utah, to learn how salt makes its way into water bodies.

Speaking to an expert in deep sea exploration, we learn how hydrothermal vents may play a role in regulating ocean saltiness, and how much the field still has to explore.

Meanwhile, listener Will wants to know how much melting ice sheets are affecting ocean salinity. But ice melt isn’t the only thing affecting salt levels when it comes to the impacts of climate change.

And... how many teaspoons of salt are in a kilogram of sea water anyway? We do the rigorous science to answer all these salient saline questions.

Featuring: Deepika - small scale salt farmer Mark Radwin - PhD candidate in geology and geophysics at the University of Utah Brenda Bowen - Geology & Geophysics, Atmospheric Sciences, University of Utah Chris German - Geology & Geophysics, Woods Hole Oceanographic Institution Prasan Khemka - Chandan Salt Works Paul Durack - Lawrence Livermore National Laboratory Bhoomi Andharia - Central Salt & Marine Chemicals Research Institute

Presenter: Chhavi Sachdev Producer: Sam Baker Editor: Cathy Edwards Production Coordinator: Liz Tuohy Studio Manager: Sarah Hockley

(Photo: Shiv Salt Works, Bhavnagar, Gujarat in India. Credit: Chhavi Sachdev, BBC)

CrowdScience listener Eleanor was lying in bed one rainy evening, listening to the radio. She lives in New Zealand, but happened to hear a weather forecast that told her it was raining in the UK too.

She started wondering: could it be the same rain falling there and outside her window in New Zealand? Can a raindrop really travel all the way around the world?

There are a number of routes the droplet could take, including traveling as moisture in the air. Presenter Caroline Steel meets meteorologist Kei Yoshimura, who puts his powerful weather simulation to work plotting the raindrop’s journey through the sky.

What if the raindrop falls along the way and gets trapped? Where might it end up? Hydrologist Marc Bierkens talks Caroline through the detours it could take, ranging from short stop-offs in plant stems to extremely long delays in deep groundwater.

Finally, could the drop of water make it to New Zealand by circulating through the world’s ocean currents? Oceanographer Kathy Gunn maps the droplet’s path through the ocean – and explains how climate change might affect its journey.

Featuring: Prof. Kei Yoshimura, Professor of Isotope Meteorology, University of Tokyo Prof. Marc Bierkens, Professor of Earth Surface Hydrology at Utrecht University Dr. Kathy Gunn, Lecturer in Climate Sciences at the University of Southampton

Presenter: Caroline Steel Producer: Phil Sansom Editor: Cathy Edwards Production Co-ordinator: Liz Tuohy Studio Manager: Tim Heffer Additional recording: Knut Heinatz

(Photo: Textures of rain on the surface of the ocean. Credit: Philip Thurston/Getty Images)

It’s often said that fine wine gets better with time, and this week’s oenophile listener Jeremy has a cellar full of dust-covered bottles. He is curious whether chemistry can account for the range of flavours that develop as wine matures, but also wonders why some of it tastes like vinegar if you leave it too long? We head off to the Bordeaux region of France, where vines were planted almost 2,000 years ago. Here, winemakers are joining forces with scientists to better understand wine ageing, a process so subtle and intricate that even the scientists refer to it as magic. In the world-famous vineyards of Chateau Margaux, presenter Marnie Chesterton learns that the key ingredient for good grapes is a sandy soil type; and that in this part of France, the warming climate is actually having a positive effect on the vines, which need very little water to thrive. Over in the lab, we meet the chemist mapping the molecules responsible for aromas associated with a well-aged Bordeaux. Featuring: Philippe Bascaules, Chateau Margaux Prof Cornelis van Leeuwen, Bordeaux Sciences Agro Dr Stephanie Marchand-Marion, ISVV Alexandre Pons, ISVV Presented by Marnie Chesterton Producer – Marijke Peters Editor – Cathy Edwards Production Co-ordinator – Liz Tuohy Studio Manager – Sarah Hockley

(Photo: Aged bottles on wine racks in a cellar. Credit: Morsa Images/Getty Images)

The Blue Ridge Parkway is 469 miles of beautiful vistas, a mountainous road that winds from Virginia to North Carolina in the USA. The route is peppered with elevation signs, telling you how many metres above sea level you are. Which has CrowdScience listener Beth wondering: as we are told that sea level is rising, will all the elevation signs need repainting?

It’s a task she’s passed over to the CrowdScience team, who like a difficult challenge. The height of an enormous pile of rock like Ben Nevis, or Mount Everest feels unchangeable. But we measure them relative to the nearest patch of sea, which is where our story becomes complicated. Unlike water in a bath, sea level is not equal around the world. The east coast of America has a different sea level to its west coast. And as host Marnie Chesterton discovers in Finland, in some parts of the world the land is being pushed up, so sea level is actually falling.

In fact, when nothing on earth - not the sea, the shore or the mountains - seems to be stable or constant, the question of what you measure from and to becomes incredibly tricky. But that hasn’t stopped oceanography and geography scientists risking life and fingers to use an ever-evolving array of technologies to find answers. In this show we find out why they care so much, and why we should too.

Featuring: Dr Paul Bell – National Oceanography Centre, Liverpool, UK Dr Severine Fournier – NASA Jet Propulsion Laboratory / California Institute of Technology Dr Jani Särkkä – Finnish Meteorological Institute Khimlal Gautam – Mountaineer and Chief Survey Officer, Government of Nepal Dr Derek van Westrum – National Oceanic and Atmospheric Administration, USA

Presented and produced by Marnie Chesterton Editor – Cathy Edwards Production Co-ordinator – Liz Tuohy Studio Manager – Steve Greenwood

(Photo: Sea Level Elevation Sign in Death Valley, California. Credit: Mitch Diamond/Getty Images)

Prayer and meditation are key features of religious and spiritual practices around the world, suggesting they’re intimately linked to the human condition. But what is going on in the brain during prayer? And is praying beneficial for our mental health?

CrowdScience listener Hilary is keen to find answers to such questions. She’s a counsellor with a strong Christian faith, and is curious to know whether science can illuminate religious and spiritual practices.

Presenter Caroline Steel talks to neuroscientists researching how our brains respond to prayer and meditation; and practices mindfulness herself to explore its similarities to prayer. She discovers that having a relationship with God may depend on more than religious practice. And is there a ‘spiritual part’ to our brains? Or is prayer just one activity among many - like going for a walk or playing music - that can have similar effects on our state of mind?

Featuring: Professor Andrew Newberg, Director of Research Marcus Institute of Integrative Health, Thomas Jefferson University and Hospital, USA Tessa Watt, mindfulness teacher Ven. Hin Hung Sik, Centre of Buddhist Studies, University of Hong Kong Dr Junling Gao, Centre of Buddhist Studies, University of Hong Kong Dr Blake Victor Kent, Westmont College, USA

Presenter: Caroline Steel Producer: Jo Glanville Editor: Cathy Edwards Studio Manager: Tim Heffer Production Co-ordinator: Liz Tuohy

(Photo: A crowd of people praying. Credit: Digital Vision/Getty Images)

Mosquitoes are responsible for more human deaths than any other animal. These tiny creatures transmit many diseases, but the most devastating is malaria. It kills over half a million people every year, most of them children.

So why are people still dying of malaria in such large numbers, when so much time and money has been invested in trying to eradicate it? What do we know about mosquitoes and malaria, and what do we still need to learn? CrowdScience visits Malawi, one of the African countries leading the way against malaria, with the rollout of the world’s first malaria vaccine programme.

Presenter Caroline Steel is joined by a live audience and a panel of experts: Wongani Nygulu, Eggrey Aisha Kambewa and Steve Gowelo. Together they explore questions from our listeners in Malawi and around the world, like why female mosquitoes feed on blood while males drink nectar; why some people are more likely to be bitten by mosquitoes than others; and how we might modify the insects’ DNA to stop them spreading diseases.

About half a million children across Malawi have been vaccinated since 2019. We visit a clinic in nearby Chikwawa to meet the staff involved in the vaccination programme there, and the mothers embracing the opportunity to protect their babies against this deadly disease.

Recorded at Malawi Liverpool Wellcome Trust (MLW), Blantyre, Malawi.

Contributors: Dr. Wongani Nygulu, Epidemiologist, Malaria Alert Centre Eggrey Aisha Kambewa, MLW entomologist, MLW Dr. Steve Gowelo, University of California San Francisco Malaria Elimination Initiative

Presenter: Caroline Steel Producer: Jeremy Grange Researcher: Imaan Moin Additional Recording: Margaret Sessa Hawkins & Sophie Ormiston Editor: Cathy Edwards Production Co-ordinator: Liz Tuohy

(Photo: A mosquito, that is silhouetted against the moon, bites a human arm. Credit: LWA/Getty Images)

When CrowdScience listener Israel from Papua New Guinea received a bad grade on a maths test in third grade, he looked around the class and realised that almost all the other students had received a better result. Since then, he has always wondered: why are some people better at maths than others? And Israel isn’t the only one to think about this: our listeners from all over the world describe their relationships with numbers, which run the full gamut from love to hate. So are we all in control of our own mathematical fate, or are some people just naturally bad at it? Presenter Anand Jagatia hears about studies of identical and non-identical twins showing how genetics and environment interact to shape our mathematical abilities. Our numerical abilities are not set in stone. It’s always possible to improve, and getting rid of negative feelings and anxiety around maths could be the key, says psychologist Iro Xenidou-Dervou. Some countries seem to support children’s maths skills better than others. China and Finland both rank highly in international league tables; education experts in both countries discuss whether there are any keys to a successful mathematics education. And there is something underlying our ability to do maths in the first place: our number sense. We hear what happens when this number sense does not work as intended – and what can be done about it. Contributors: Professor Yulia Kovas – Goldsmiths University of London, UK Professor Pekka Räsänen – University of Turku, Finland Assistant Professor Zhenzhen Miao – Jiangxi Normal University, China Dr Iro Xenidou-Dervou – Loughborough University, UK Professor Brian Butterworth – University College London, UK Presented by Anand Jagatia Produced by Florian Bohr Editor: Cathy Edwards Production Co-ordinator: Liz Tuohy Studio Manager: Jackie Margerum

(Photo: Boy scratching head in front of blackboard. Credit: Jose Luis Pelaez Inc/Getty Images)

Coastlines around the world are changing, causing serious problems for the many communities living near the sea, as well as vital and fragile coastal ecosystems.

In the second of a two-part special on coastal erosion, CrowdScience explores the best ways to tackle this problem. Presenter Caroline Steel visits the Caribbean island of Puerto Rico to see the various methods they use to protect their coasts.

First up: ‘riprap’ – rocks strategically placed to keep the encroaching sea at bay. The problem is, while it protects the area immediately behind the rocks, riprap can exacerbate erosion nearby.

But there are other, more nature-friendly solutions, including sand dune restoration. Caroline picks up her shovel and helps to re-plant dunes, destroyed in the past by erosion as well as sand extraction for the construction trade. The roots of these plants stabilise the dunes, while building boardwalks prevents further damage from humans.

Nature also offers the perfect offshore protection against coastal erosion: coral reefs. These are the first line of defence in absorbing the power of the ocean’s waves. Down on the beach, we see for ourselves just how effective they are. The reefs face threats, but restoration plans are afoot. We visit a nursery that grows corals to plant out on the reefs – and find out about corals’ surprising cannibalistic tendencies in the process.

Featuring: Professor Robert Mayer - Director of Vida Marina, Center for Conservation and Ecological Restoration, University of Puerto Rico Nada Nigaglioni - Biology student, University of Puerto Rico Ernesto Diaz - Caribbean Regional Manager at TetraTech Dr Stacey Williams - Executive Director, ISER Caribe

Presenter: Caroline Steel Producer: Hannah Fisher Editor: Cathy Edwards Production Co-ordinator: Liz Tuohy Studio Manager: Emma Harth

(Photo: Coast restoration measures at Ultimo Trolley Beach, Puerto Rico. Credit: BBC)

Around the world, coastlines are constantly changing due to the power of waves, currents and tides. Coastal areas are also some of the most heavily populated and developed land areas in the world. So it’s not hard to see how the natural process of coastal erosion can cause serious problems for us.

It’s an issue that’s been bothering CrowdScience listener Anne in Miami Beach, Florida. She can see the beach from her window and wonders why after every storm, several trucks arrive to dump more sand on it.

In this first of two programmes, CrowdScience visits Anne’s home in south Florida and finds out how erosion threatens Florida’s famous beaches. Caroline Steel speaks to geoscientist Dr Tiffany Roberts Briggs and hears why it’s such a problem for this tourist-reliant state. Tiffany explains the delicate balance between natural processes and human infrastructure.

Meanwhile, the Caribbean island of Puerto Rico declared a state of emergency in April 2023 due to coastal erosion. Caroline witnesses the impacts of erosion first-hand, as Ruperto Chaparro shows her abandoned houses crumbling into the sea.

But how can we quantify the rate of erosion? Dr Kevian Perez in the Graduate School of Planning at University of Puerto Rico explains the methods they use to monitor Puerto Rico’s coastlines, and how they are evaluating the effectiveness of different mitigation methods.

However, some of the methods used to protect coastal communities from the encroaching sea have done more harm than good. So what are the best ways to tackle this problem? That’s what we’ll be exploring in next week’s programme.

Presenter: Caroline Steel Producer: Hannah Fisher Editor: Cathy Edwards Production Co-ordinator: Liz Tuohy Studio Manager: Steve Greenwood and Bob Nettles

Featuring: Dr Tiffany Roberts Briggs, Associate Professor at Florida Atlantic University Ruperto Chaparro, Director of Sea Grant Programme, University of Puerto Rico Anabela Fuentes Garcia, Villa Cristiana community leader Dr Kevian Perez, researcher at the Coastal Research and Planning Institute of Puerto Rico at the Graduate School of Planning

(Photo: Puerto Rico after Hurricane Maria. Credit: Orlando Sentinel/Getty Images)

How do we know where a sound is coming from?

Another chance to hear this ear-opening episode, exploring a question from CrowdScience listener Chiletso. One day, he heard his son bounce a ball and instantly knew the direction it was travelling. How?

Anand Jagatia sets out to discover what makes left, right, up and down sound so different.

First, he gets blindfolded, so Alan Archer-Boyd, former auditory scientist and lead engineer at BBC R&D, can put his sound localisation skills to the test. It turns out that having two ears and pinnae, those flappy bits of cartilage on the side of your head, help a lot.

Professor Eric Knudsen shares how the barn owl’s asymmetrical ears allow it to hunt mice, even in complete darkness.

And Anand uncovers how far he can push his own spatial hearing. Blind activist and researcher Thomas Tajo teaches him how to echolocate like a bat, and Dr Lore Thaler explains what is going on in the brain of experienced echolocators.

This programme was originally broadcast in March 2023.

Presented by Anand Jagatia Produced by Florian Bohr for the BBC World Service

Image: Boy with hands at his ears Credit: Silke Woweries/Getty Images

For some it's a way to get closer to God, for others a tried and tested way to lose weight - but listener Amine wants to know if fasting has any other, unexpected health benefits? So presenter Marnie Chesterton cuts down on cookies and investigates the science behind low-calorie or time-restricted eating. She hears how some cells regenerate when we're deprived of food, which one researcher says could reduce breast cancer rates. And she finds out what happens in our brains when our bodies rely on our own fat reserves for fuel. Presenter: Marnie Chesterton Producer: Marijke Peters

(Image: Clock on an empty plate. Credit: Getty Images)

Why is it that computers are so much faster than brains at some tasks?

Or could human brains one day be used to better effect? Listener Praveen from India was wondering how it can be that supercomputers are so very powerful compared to the human minds that created them. So CrowdScience, with the help of a small voice-activated guest presenter, is off to discover how the first computers remembered what they were told, how a million processors are being connected together to mimic a small percentage of a human brain, and how the mind-boggling speeds of modern computing is enabling the current leaps in artificial intelligence.

Producer: Alex Mansfield Presenter: Marnie Chesterton

Speakers: Sarah Baines, David Lewis - Museum of Science and Industry, Manchester James Sumner, Steve Furber - University of Manchester Aldo Faisal - Imperial College, London.

(Photo: 3D transparent human head and brain image. Credit: Getty images)

Kenyan listener Docktor can’t help himself. When music is playing he must move to the beat and he wants to know why. What role does dance play in human evolution? And what does dance mean to us? To help answer the many twists and turns in Docktor’s questions, the CrowdScience team heads to one of the most vibrant and diverse dance scenes in the World, Havana in Cuba. For Cubans dancing is at the heart of their cultural identity. They tell stories, bond with others, practice religion and celebrate their African ancestry through dance ¬– which came to Cuba with the slave trade.

For all humans, dancing is intimately connected to our love of music and is likely to be one of our oldest cultural practices. But why would our ancestors have wasted energy on what superficially seems to serve no survival benefits? Evolutionary anthropologist Bronwyn Tarr tells us that one clue lies in the brain. When we dance with others our brains reward us with a cocktail of feel-good hormones and this likely leads to profound social effects.

Presenter Anand Jagatia gets challenged on the dance floor, discovers how deeply rooted dance is in Cuban society and why we should dance more.

Presenter: Anand Jagatia Producer: Louisa Field

(Image: Dancers in Cuba)

Humans have the potential to eat pretty much anything – but the reality is we don’t. Wherever we live in the world, we eat just a small fraction of the foodstuffs available and show strong preferences for certain foods over others. Those preferences can change dramatically from person to person, or as the saying goes – one man’s meat is another man’s poison. Then at the extreme end of the spectrum you get so-called ‘fussy eaters’ who reject so many foods that they are confined to beige diets of crisps, crackers and cereal.

So why do we show such different preferences for food? And why are some people fussier than others? That’s what CrowdScience listeners Orante Andrijauskaite in Germany and Anna Nicolaou in Belgium would like to know, and what Datshiane Navanayagam is off to find out.

She discovers how both biology and culture shape whether a food is disgusting or delicious and learns why we should stop giving children a hard time about finishing their dinner. She also learns how global cuisines evolved and what that can teach us about helping fussy eaters to overcome their food fears.

Presenter: Datshiane Navanayagam Producer: Anna Lacey

(Photo: Fried Bugs in Bangkok night market. Credit: Getty Images)

Carbon dioxide levels are far higher than at any other point in human history, thanks to our reliance on burning fossil fuels. But having pumped huge amounts of CO2 into the air, are there ways to get it back out again? If so, where would we put it all? And the big question: can that help solve our climate change problem, or is it a distraction from the urgent task of reducing our emissions?

When CrowdScience delved into ancient carbon dioxide levels last year, it sparked a flurry of emails from our listeners asking these questions and more, so this week we investigate our options for restoring equilibrium to our atmosphere. Since the CO2 came from deep underground - in the form of coal, oil and gas - can we put it back there? We travel to Iceland where they’re capturing carbon dioxide directly from the air - and turning it into rock. Presenter: Marnie Chesterton Producer: Cathy Edwards

(Photo: Nesjavellir geothermal power plant in Iceland. Credit: Getty Images)

Short-sightedness is reaching epidemic proportions around the world. The way things are progressing, one-third of the world’s population – 2.5 billion people - could need glasses by the end of the decade. And scientists are beginning to understand why: children spend too much time indoors, bent over screens and books. Marnie Chesterton travels to Singapore, where rates of myopia are one of the highest in the world and to see how the government is curbing the condition with an array of tools, from eye-drops to sunshine remedies.

She does so in the hope of better understanding whether screens are bad for children’s eyes, a question raised by a concerned Mexican father, Fernando, about his two-year old daughter.

Presenter: Marnie Chesterton Producer: Graihagh Jackson

(Photo: A little girl wearing headphones while using a digital tablet at home. Credit: Getty Images)

Will gravity on earth ever change? Why do insects fly towards the light? Is the plasma in a TV the same as plasma in a fusion reactor? Why are mosquito bites so itchy? What does the Higgs boson do for the Universe? In a Q+A special, Marnie Chesterton is joined by scientists Malcolm Fairbairn, Kate Lancaster and Erica McAlister to tackle a selection of questions from the CrowdScience inbox.

Presenter: Marnie Chesterton Producer: Alex Mansfield

(Photo: Alates insects light bulb and night. Credit: Getty Images)

Dementia affects nearly 50 million people worldwide – but doctors are still struggling to find a cure. CrowdScience investigates why this particular group of brain diseases are so hard to treat, from the difficulties around diagnosis to why the drugs just don’t currently work.

In the absence of a medical solution is it time to take a new approach? As geneticists develop tests to predict who might develop brain disease, there are others focusing on better care for those who already have it. Presenter Bobbie Lakhera visits a village in the Netherlands helping sufferers live longer independently, and hears how music projects improve non-verbal communication.

Presenter: Bobbie Lakhera Producer: Marijke Peters

(Photo: Neurology research examining the neurons of a human head to heal memory loss or cells due to dementia. Credit: Getty Images)

Since the end of the 19th century, scientists have been predicting we would be eating a meal in a pill, but is it a serious answer to the world’s food problems? That’s what Australian listener Bridget is wondering and whether it’s possible to produce an artificial food source that can provide all the nutrients for healthy human life.

With increasing urbanisation, diets are changing and estimates suggest food production will have to increase some 60 percent by 2050 to keep up with demand. But can we provide all that extra food with limited natural resources and traditional farming methods?

First, Marnie Chesterton finds out what artificial food is currently available and whether the existing products are healthy. And while a meal in a pill might sustain our bodies, will it sustain our minds? The experience of eating involves so much more than simply taking in the right nutrients, as Marnie discovers at the Gastrophysics Chef’s Table, a restaurant and multi-sensory dining experience. On the menu is jellyfish, a possible alternative source of food for the future. It’s in plentiful supply in our oceans, but like eating insects, the thought of it may be disgusting to some, so Marnie explores how sensory-driven strategies can be used to make these food sources more appealing.

CrowdScience also visits the future of farming: A hydroponic vertical farm called Growing Underground, which is built in World War Two air-raid shelters under London. Using LED lighting instead of sunlight, leafy vegetables grow very quickly and need very little space. With higher crop yields per square metre than traditional farming, vertical farms allow fresh produce to be grown in urban centres with less impact on the environment.

Hydroponic farming is something the European Space Agency is also experimenting with as part of Project Melissa, which is developing a closed loop ecological system - using rats instead of astronauts - aimed at one day helping us grow fruit and vegetables on Mars. Listen to the podcast version of the programme to hear this interview.

Producer: Helena Selby

(Photo: Pills on a plate. Credit: Getty Images)

Listener Nikolai sends CrowdScience hunting through space and time with his deceptively simple question. Can we find perfect stillness? You are probably reading this sentence whilst standing or sitting still. So is it a daft question? We discover that there are no simple answers as we unravel the science of motion, which tells us that we cannot always trust our senses to tell us ‘the truth’ about the natural world.

The ancient Greeks believed it was the sun that rises and sets each day and this idea remained until the 16th century astronomer Nicolaus Copernicus showed us that this an illusion – that we are the ones in motion, orbiting the Sun. Later, through the work of Isaac Newton and then Albert Einstein, scientists came to the conclusion that nothing in the universe can ever be truly still. Except perhaps, the fastest thing in the universe – light.

Confused? Don’t worry, so is Marnie Chesterton who sets out to explore not just the science of stillness but also the physics of stopping. To satisfy listener Nikolai’s curiosity about motion in space, CrowdScience also travels to ESA’s European Space Research and Technology Centre in the Netherlands. Here we find out how you stop a space craft and hear the story of when things got prickly for astronaut Tim Peake and his crew when docking at the International Space Station.

Presenter: Marnie Chesterton Producer: Louisa Field

(Photo: Astronaut wearing pressure suit against a space background. Credit: Getty Images)

Are you the master of your own decisions? Independent-minded? A free spirit? Like it or not, the answer is probably no - as we are profoundly influenced by the people around us. But why do humans follow the crowd? CrowdScience listener Cath Danes wants to know and this week we are going to be giving her answers at the BBC’s Free Thinking Festival in Gateshead.

Marnie Chesterton is joined by a crack team of neuroscientists and psychologists, who reveal the secrets behind our inner sheep. We also run an experiment to find out whether you should trust the wisdom of the crowds with life’s big decisions.

Presenter: Marnie Chesterton Producer: Anna Lacey

(Photo: A flock of sheep being herded in a pasture. Credit: Getty Images)

Unlike nuclear fission power stations, which leave harmful radioactive waste to be stored or disposed of for thousands of years, a nuclear fusion power plant would create precious little burden on future generations. The fuel source would be seawater, and the energy created limitless.

Back in the 1950s, the technology to “tame the hydrogen bomb” seemed just a few decades away from practical deployment, and governments across the divide of the cold war shared the challenges, costs and laboratories.

But to the outsider, it might look like progress has been slow. In 1997 the Joint European Torus at Culham in the UK set the world record for energy released from a controlled fusion reaction, but even that was less than the energy was put in.

Keeping the plasma – the super-hot atoms of exotic types of hydrogen – at temperatures many times the temperature of the sun safely in place inside a magnetic field is not a trivial task.

Last year construction of the International Experimental Thermonuclear Reactor, ITER, reached its halfway point at its huge home in France, and if all goes to plan it should produce its first plasma by 2025. The hope is that operational fusion reactions will take place within a decade after that, paving the way for its successor DEMO - which would actually generate electricity - to be built sometime before 2050.

But in parallel with the big intergovernmental roadmap, in recent years a number of small commercial startups have joined the race to achieve commercial fusion energy. With their various different approaches and more ambitious timelines, will the private sector beat the publicly funded science to the goal?

Presenter: Bobbie Lakhera Producer: Alex Mansfield

(Photo of ITER Organization, with permission)

Humans have used dogs' excellent sniffing talents ever since our ancestors figured out that canine companions could help them track down their next meal.

But what about other animals? Can they take us beyond the limits of our own senses? That's what CrowdScience listener Beth wants to know, so we obligingly try to sniff out some answers.

After immersing ourselves in the world of insect senses at our local zoo, we visit an insect lab in Germany to find out whether sniffer bees could take over from sniffer dogs. And could ants help us fly the drones of the future? We meet the scientists trying to turn ant vision into computer code, to send robots into places GPS can't reach.

Presenter: Nastaran Tavakoli-Far Producer: Cathy Edwards

(Photo: A bee on a human finger. Credit: Getty Images)

A cacophony of singing and screaming creatures’ accents are explored to answer: Can animals of the same species from different places communicate with each other? Presenter Geoff Marsh tries to identify how different these calls really sound for CrowdScience.

From wolves to birds to whales and chimpanzees, most animals use sound to communicate, but if groups in different places vocalise in different ways, they may not be able to communicate with others.

CrowdScience questioner, Kitty, sets us on an exploration of the vast and varied world of animal communication with inspiration from her dog Monty.

Presenter: Geoff Marsh Producer: Rory Galloway

(Photo: Three wolves howling on a cold day. Credit: Getty Images)

From worms who time their mating ritual with an inner lunar calendar, to how full moons could cause cows to give birth early. Listener Andreas sends CrowdScience on a mission to separate fact from fiction.

Presenter: Marnie Chesterton Producer: Marijke Peters

Picture: The moon rises over Kadam mountain in Uganda, on January 31, 2018, during the lunar phenomenon referred to as the 'super blue blood moon'. Credit: Yasuyoshi Chiba / AFP / Getty Images

Scientists have been searching for dark matter for 80 years, so CrowdScience wondered whether they could find it faster. Armed with a boiler suit, hard hat and ear defenders, Marnie Chesterton travels over a kilometre underground into a hot and sweaty mine to see how we could catch dark matter in action. She investigates various theories as to what it might be with popping candy and gazes at galaxies to determine how we know it exists in the first place. But most importantly, she questions whether it really matters. And, as our Singaporean listener Koon-Hou askes, what impact would finding it have on our everyday lives?

Presenter: Marnie Chesterton Producer: Graihagh Jackson

(Photo: Finding dark matter could have galactic implications. Credit: Getty Images)

Carbon is special, but is it necessarily the unique building block of life in the universe? Science fiction has long speculated on non-carbon biochemistries existing in the universe – notably in the work of authors such as Isaac Asimov as well as in the popular American TV series Star Trek, which once featured a rock-munching, silicon-based life form called ‘Horta’.

Marnie Chesterton explores the real science behind this intriguing idea and wonders whether in the current search for Earth-like planets elsewhere in the galaxy, we should be looking at completely different possible sets of rules when it comes to the hunt for life?

Producer Alex Mansfield Presenter Marnie Chesterton

(Photo: Saturn viewed from Titan moon. Credit: Getty Images)

How far can you see? A few kilometres down the road? Or do you struggle to see past the end of your own nose? Well one listener thinks he might be able to see 15 quintillion miles away... but can he really? Marnie Chesterton and Bobbie Lakhera are on the case for this week’s multi-question human body special. As well as delving into the power of vision, they also discover why male mammals have nipples despite not needing to breastfeed, and Marnie puts herself in a giant refrigerator in the name of finding out why some people feel the cold more than others.

Presenter: Marnie Chesterton Producer: Anna Lacey

Meet the entrepreneurs turning bugs into food and get top tips on how to cook them. In this week’s episode we return to the topic of edible insects and the story of Kahitouo Hein’s caterpillar factory in Burkina Faso, West Africa. Kahitouo is trying to turn a traditional food like the shea caterpillar, available for just a few weeks a year, into a year-long sustainable staple for the whole population.

We also put your questions about edible insects directly to the researchers in Burkino Faso. Discover the best way to cook a bug, explore the curious effects of hornet venom and find out whether eating insects is better for the environment then eating red meat.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Louisa Field

(Photo: Worker at Kahit’s factory cooking caterpillars)

Most of us instinctively know when someone’s singing and when they’re talking. But since music and speech are both just sounds, how do our brains tell them apart? This week’s question comes from Eugene, a music teacher in Northern Ireland, who often hears music in people’s speech, and wonders why.

Step forward, the ‘speech-to-song illusion’. This curious phenomenon means that when certain spoken phrases are repeated, they turn into music as if by magic. We talk to the Diana Deutsch, the scientist who discovered this illusion, and find out what it reveals about how the brain is adapted to understand both music and speech.

But are some languages more musical than others? Many people around the world speak tone languages, where the pitch of a word affects its meaning. One such language is Dinka, spoken in South Sudan; we meet a Dinka speaker and hear how respecting the melody of the language is essential when writing songs.

Presenter: Datshiane Navanayagam Producer: Cathy Edwards

Dinka recordings courtesy of Elizabeth Achol and Anyang Malual

(Photo:Young woman listening to music on yellow headphones. Credit Getty Images)

Dogs have been living and working with humans for thousands of years. But they’re much more than just pets. As any dog owner will tell you, the bond we have with our canine friends is often so strong that they feel more like family.

So how is it that dogs have come to fit so seamlessly into human life?

That’s what CrowdScience listener Peter Jagger in the UK wants to know, and Marnie Chesterton is off to sniff out some answers. She starts by revisiting a previous episode of CrowdScience based in Sweden, where she saw the dog-human bond come alive during a moose hunt. She then heads to the Dog Cognition Centre in Portsmouth to discover how a unique and often unconscious communication system helps our dogs to understand us. Finally, Marnie finds out about the fate of dogs that are no longer wanted by their humans. After thousands of years of domestication, can they ever live without us?

Presenter: Marnie Chesterton Producer: Anna Lacey

(Photo: Image of young girl with her dog, alaskan malamute. Credit: Getty Images)

Crowdscience revisits the evidence on the best forms of biometric identification. Earlier in the year we explored digital fingerprints, gait (walking style) recognition and iris scanners. Today presenter Anand Jagatia looks at systems which use your face and your voice to identify you. One airline is currently testing facial recognition in airports as a means of replacing your passport. Meanwhile, Anand tries to fool a speech recognition system that measures over a thousand characteristics of your voice in order to protect your identity. But will it be able to cope if you have a cold?

Presented by Anand Jagatia Produced by Marijke Peters.

Picture: Facial Recognition Credit: Getty Images

Reindeer castration, plants get chatty and more quirky science revealed in this Christmas special of CrowdScience where we will also be hearing from the people that make this series possible. That’s you – our listeners.

CrowdScience has been on air for just over a year which means we’ve had over 60 adventures. Every time we put a show together there’s a heart-breaking process where amazing facts we wanted to share end up on the cutting-room floor. To celebrate the holidays we’ve gone scavenging for the best untold stories, edgy science facts and incidents from behind the scene. Presenter: Marnie Chesterton Producer: Louisa Field

Picture: Reindeer in Snow Credit: Getty Images

It lurks behind sofas and collects in corners, apparently appearing from nowhere. But what is household dust? And should we bother sweeping it away? That’s what Australian listener Moshe wants to know and what Marnie Chesterton is off to find out for this week’s CrowdScience. She embarks on a mission to discover not only what dust is made of, but whether it poses any health risks. Although most people sweep it away without a thought, dust contains all sorts of secrets about our habits and everyday lives. Marnie finds out how dust can reveal the pets you keep, the chemicals in your surroundings, the location of your house and how fecal bacteria can uncover whether more men or women live in your home.

Presenter: Marnie Chesterton Producer: Anna Lacey

(Image: Woman Vacuuming Up Dust. Credit: Getty Images)

Trees are old – they transcend human generations – but are they the oldest living things on Earth? This story began in June 2017 when we explored a question sent in from CrowdScience listener William. Many of you got in touch after the programme with questions of your own. So we’re revisiting our trees programme but also exploring another question from listener James, who wants to know what, pound for pound or gram for gram, is the strongest animal alive on Earth today? Marnie Chesterton wrestles with one of them and – spoiler alert – it’s not a gorilla.

Presenter: Marnie Chesterton Producers: Jen Whyntie

(Photo: Kumbuka, a 15-year-old western lowland gorilla. Credit: Oli Scarff/Getty Images)

Dodos are dead, but are they gone forever? Reviving extinct species is a trope of science fiction, but real-life scientists are working on every stage of the problem today. Meeting scientists focused on uncovering ancient animal genomes, or reviving individual cells to conserve species still around, Marnie Chesterton seeks out whether new technologies might, just possibly, bring back the iconic dodo. But what would it take to bring back that most iconic of extinct species? Following listener Rachel’s question, CrowdScience gets to grips with the dodo’s past, and finds out what’s left of this iconic bird, meeting the scientists inadvertently piecing it back together.

Presenter: Marnie Chesterton Producer: Rory Galloway

Picture: An accurate reconstruction of nesting Dodos Photo Credit: Dr Julian Hume

How does technology affect how we fall in love? Crowdscience travels to India to answer listener Erin’s questions about the impact of the internet on our search for soulmates. We meet the traditional matchmaker who says her service provides security in an era of digital fraud. And ask whether computer algorithms are the best way to help people make permanent romantic connections?

Presenter: Chhavi Sachdev Producer: Marijke Peters

(Photo: A couple kiss while taking a selfie. Credit: Getty Images)

Some of us want to be up with the larks, while others are more like night owls. But is our preference down to our genes, or more to do with habits and surroundings? We set out to find the answers, inspired by a question from Kira, a night owl CrowdScience listener in Philadelphia, USA.

Our daily, or circadian, body clocks are a hot topic of discussion at the moment - this year’s Nobel Prize for Medicine went to three scientists who discovered the gene that makes these clocks tick. To answer our listener’s question, we need to know why different clocks tick at different rates, so we visit a specialist sleep centre to see how having a slow-ticking clock makes it hard for you to leap out of bed in the morning.

And the morning sun helps all of us regulate our daily rhythm, so what happens when it doesn’t rise at all? We travel to Tromsø, in the far north of Norway, to see how morning and evening types fare during the long polar nights - and meet the reindeer who seem to be able to switch off their daily clocks altogether. Meanwhile down near the equator, we hear about the hunter-gatherer community in Tanzania where there’s nearly always someone awake.

Sami song, the joik of Ráikku-Ánte, is performed by Ken Even Berg

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Cathy Edwards

(Image: L - Women smiling on a run R - Women DJ. Credit: Getty Images)

Sometimes our memory fails us and we wish facts would just stick better. Listener Mothibi is a student and has spent three years trying to remember as much as possible for his exams. He wants to know how he can train his brain to better to remember things – and does the brain have a limit on how much stuff we can cram into it?

To find the answers presenter Marnie Chesterton seeks help from memory magician, Simon, at the European Memory Championship. Using the loci technique she accomplishes a memory feat she didn’t think possible. Thought to have been developed by the Greeks, the loci method is a technique that enables the brain to remember extraordinary amounts of information. It turns out, we all have the right wiring to remember more and better, but we need to train our brains.

Also, CrowdScience heads to Cambridge University where Marnie Chesterton lands herself in a study. The scientists scan her brain while she exercises her memory muscles and we discover why sometimes memories get muddled up.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Louisa Field

(Image: Woman scratching head, thinking brain melting into lines. Credit: Getty Images)

People often talk about being descended from apes. But go back a bit further and we have a more unlikely ancestor – fish. Improbable as it may sound, the creature that gave rise to every bird, reptile and mammal on Earth today lived a fully aquatic life.

So how did it switch to life on land? And how hard was it to swap swimming for walking and breathing fresh air? That’s what CrowdScience listener Pierre in France wants to know, and what Marnie Chesterton is in Scotland to find out. She goes fossil hunting with members of the TW:eed Project team, as they try to uncover remains of creatures that are crucial in helping solve the puzzle of terrestrial life. She also discovers the landscape these early ancestors walked into – an alien and relatively empty world completely different to what we see today - where grass and flowers were yet to evolve.

But not everything in this story is preserved in rock. Marnie goes to see a living relic of this period of evolution, and finds out what it can tell us about possibly the most important event in the history of our species.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Anna Lacey

(Image: Artists impression of underwater environment of Carboniferous swamp depicting a rhizodont; a large predatory fish. Credit: Mark Witton)

Unpleasant man-made noise is something that disturbs many of us and even damages our health. But as millions more people move into crowded cities around the world, it's a cacophony that we almost unavoidably create ourselves. CrowdScience listener Diana from New York City in the USA got in touch to ask how we can temper the din and live a more peaceful life. Presenter Anand Jagatia heads to an acoustics lab at the University of Salford in Manchester, UK, to meet the researchers and engineers investigating the best ways to make cities more pleasant for our ears whilst still maintaining the ‘buzz’ of city life. And reporter Chhavi Sachdev takes us to Mumbai in India, where we discover how sound mapping is being deployed on the city’s streets as the first step to improve the life and health of its citizens.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Jen Whyntie

(Image: Children cover their ears as the truck convoy front passes. Credit: Getty Images)

Is there any scientific proof of an afterlife? Six months ago, CrowdScience tackled a question from a listener who wanted to know whether there was life after death. But following more listener emails, presenter Marnie Chesterton returns to the subject to investigate the world of ghosts, souls and parapsychology. She meets Professor Susan Blackmore, who studies out-of-body experiences and has spent decades hunting for scientific proof of life after death. And she visits the woman who, despite dying in the 1950s, is alive and thriving on a cellular level and helping scientists find cures for cancer, Parkinson’s and other diseases, in laboratories across the world…

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Produced and Presented by Marnie Chesterton

We test the science behind parasitic therapy to answer listener Michael’s question about whether intestinal worms can help us stay healthy, and visit a deworming programme in a rural Ugandan village.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Marijke Peters

(Picture: Tapeworm in human intestine, Credit: selvanegra/Getty Images)

Carbon dioxide levels in our atmosphere today are higher than at any point in human existence. But going back further into Earth’s history, when do we find concentrations as high as they are now - and what was the planet like back then?

CrowdScience sets out to answer our listener Thomas’s question, travelling back through time with the help of Antarctic ice cores, ancient plant fossils, and microscopic popcorn-shaped organisms called foraminifera, all of which hold clues to past climates.

Enlisting the help of chemists, botanists and palaeontologists, we find out about the huge swings in atmospheric carbon dioxide from prehistoric times to the present day, and ask the all-important question: can this help us understand what's happening to our climate now?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Cathy Edwards

(Image: Polar bear on an ice floe. Credit: Getty Images)

Human Organs are in short supply. But what if you could grow new ones in the lab? And if you donate your body parts to help others, where might they end up? That's what Sarah Gray wanted to know after making the difficult decision to donate the body of her son, Thomas, to medical science after he died from an incurable disease shortly after being born. Sarah then contacted the scientists whose research has been made possible by Thomas’ donation and discovered just how he is contributing to research which, may one day mean that organ donation is no longer necessary.

Presenter Bobbie Lakhera talks to Sarah about her decision and meets some of the scientists working to create biological artificial lab-grown organs, tissues and even bones.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Bobbie Lakhera Producer: Louisa Field

(Image: A doctor taking or delivering a bag containing a human organ for transplant. Credit: Getty Images)

Is it fair to kill invasive species which humans have introduced? When people move around the world, many of their favourite – and not so favourite - animals tag along for the ride. From cane toads through to rats, cats and crayfish, so-called ‘invasive species’ can destroy ecosystems and kill off native wildlife. CrowdScience listener Jude Kirkham wants to know if eradicating these invaders is justified.

One country determined to do something about invasive species is New Zealand, where rats, stoats and possums are causing irreparable damage to the country’s unique bird life. If nothing is done, the iconic Kiwi could be extinct within 50 years. The government and volunteer groups across the country have responded with a plan to eradicate predatory mammals from New Zealand by 2050. But is all the time, energy and money needed to do this really justified? And is it morally right to kill off an animal species that humans introduced in the first place?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Anna Lacey

(Image: Headshot of a Possum Credit: Getty Images)

Just one per cent of vehicles are powered by electricity, but CrowdScience listener Randall from Lac du Bonnet in Canada wants to know how quickly that might change, and whether one day all cars could be electric. Marnie Chesterton begins her journey in an electric car, stuck in traffic on a Los Angeles freeway.

It was in California where the modern electric car revival began in the late 1990s with the EV1 – popular with Hollywood celebrities like Mel Gibson and Danny DeVito. More than two decades on, several countries have pledged to go all-electric in future. The latest is China, who currently lead the world in the number of electric vehicles on the road. But is the planet’s power infrastructure even capable of supporting this global electric dream?

Marnie talks to experts about the practicalities of power supply and charging, takes a ride in an electric prototype with enough acceleration to impress even the most cynical petrol head and discovers an extraordinary vision for the future of personalised urban transport.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Jennifer Whyntie

(Image: Electric power cord plugged in and recharging the electric vehicle Credit: Getty Images)

Nuclear weapons and mega asteroids: what would the aftermath look like? CrowdScience explores past extinction events and future dystopias.

In a past episode, CrowdScience headed to Denmark to find out whether humans could go the way of the dinosaurs – mass extinction triggered by a large asteroid impact 66 million years ago. Although no killer rocks are on route to Earth any time soon, we do not have to look far for other dystopias.

“Do we have enough nuclear weapons to destroy the world?”, listener Ronald from Uganda asks CrowdScience. It turns out there is a web app which can help answer this question. Together with its maker nuclear historian Alex Wellerstein, presenter Anand Jagatia tests hypothetical nuclear disaster scenarios and uncovers the nature of nuclear destruction in interviewees with climate scientist Alan Robock.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Louisa Field

(Image: Explosion of a nuclear bomb Credit: Getty Images)

CrowdScience is uncovering the super-powers of spiders, flies and the most irritating mosquitos.

Anand Jagatia meets spider specialist Jamie Mitchells at London Zoo to find out how spiders create such vast webs and speaks to researchers in Sweden about how they are trying and succeeding in recreating spider’s silk.

Rory Galloway heads to Cambridge University’s Fly Lab to find out how their tiny brains process the world up to four times faster than humans.

And Bobbie Lakhera is at the London School of Hygiene and Tropical Medicine to find out how attractive she is to mosquitos and how they use their super-senses to home-in on our blood.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Laura Hyde

(Image: Close-up of a Jumping Spider. Credit: Getty Images

CrowdScience dives back into a debate about trees and their ability to tackle air pollution. Growing trees take in carbon dioxide and emit oxygen, but their leaves also attract tiny particles, which can get into our lungs and brains. So how good are they at cleaning our clogged up skies? Following on from our original programme, CrowdScience was contacted by a team of researchers in the UK who claim tress may be as much as 50 times better than previously thought at mopping up particles, and learn that hedges may help us stay healthy on roads. Also in the programme, we discover what pollutants are doing to our brains and reveal research which shows that keeping house plants can significantly reduce pollution inside the home.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Marijke Peters

CrowdScience heads to the Sydney Science Festival in Australia where, from a special event at The Powerhouse Museum, we reveal answers to questions listeners have been sending in such as: What living thing has the most toxic venom? What is déjà vu? And why do our fingers wrinkle in the bath? To tackle our listeners’ questions about life, Earth and the universe, presenter Marnie Chesterton is joined by four special guests who will bring the good, weird and bemusing from the world of science to the stage.

Prof Shari Forbes, Professor in Forensic Science at the University of Technology Sydney,aims to help police and forensic teams establish a more precise time of death in missing person and homicide cases.

Dr Katie Mack is an astrophysicist at the University of Melbourne. Her work focuses on finding new ways to learn about the early universe and fundamental physics using astronomical observations.

Dr Jonathan Webb runs the science unit at ABC RN. He is also a former neuroscientist and a former science reporter for BBC News in London.

Dr Alice Williamson is a chemistry lecturer and researcher at The University of Sydney. She hosts a weekly science segment, Up and Atom on FBi Radio in Sydney, co-hosts RN’s Dear Science, and is a regular guest on Dr Karl's Shirtloads of Science podcast.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Marijke Peter and Jen Whyntie

(Image: Koala in tree Credit: Getty Images)

Is it possible to get power from lightning? This was the first CrowdScience question posed by listener John Emochu in Kampala, Uganda, in November 2016. We revisit John’s story as presenter Marnie Chesterton goes hunting for answers at a lightning lab in Cardiff, Wales, where she discovers just what lightning lab is, and how to make a tiny – but very loud – lightning bolt. And we tackle the best of the many questions that came into our inbox about thunderstorms after the original broadcast – from how many types of lightning exist to whether antennae in the clouds could gather electricity. Finally, we head to Kampala to meet listener John to hear just what he thought of the programme and what life is really like in one of the lightning capitals of the world.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Jen Whyntie

(Image: Artist impression of lightning inside a conical flask. Credit: Getty Images)

** Contains some upsetting scenes **

As a species, we humans can be uniquely horrible to our own kind. But are we the only animal to commit murder? Listener Michelle’s question sends CrowdScience trekking – and getting lost - in the Budongo rainforest in Uganda in search of one of Man’s closest relatives, the chimpanzee.

We hear from the scientists, who only days before the team’s arrival at the camp, witnessed a gang of chimps brutally killing another adult. But does chimpanzee lethal aggression pass muster as murder? We head to the capital Kampala for some legal advice and take a look at the grim history of putting animals on trial.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Geoff Marsh Producer: Louisa Field

(Image: Closeup of angry chimpanzee Credit: Getty Images)

How do we end up speaking the way we do? What's happening in our brains and mouths to make us sound so different from each other - even when we’re speaking the same language? This week on CrowdScience we return to our listener Amanda’s question of why there are so many accents, and discover more about what our accents say about us.

We visit Glasgow in Scotland, home to one of the most distinctive dialects of English, to see how social status and age affect the way we speak; and investigate another of our listeners’ questions: is there really such a thing as a ‘political accent’?

But how do babies pick up accents in the first place – and is it impossible to learn new sounds later in life? Presenter Nastaran Tavakoli-Far discovers something unexpected about her own accent, visits a voice coach to try and sound Texan, and uses ultrasound to try and get her tongue round new sounds.

And you can find out how much of an accent expert you are, by taking part in our online quiz.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk Presenter: Nastaran Tavakoli-Far Producer: Cathy Edwards

(Image: Woman holds hand near ear and listens carefully alphabet letters flying in. Credit: Getty Images)

People said they’d never catch on. Mobile phones, the internet and even robot assembly lines all once seemed like niche technologies. But today they are at the heart of the modern world.

But just how far can technology go? Could machines start to compete with humans in making complex and life-changing decisions, like those made by lawyers and judges? That’s what CrowdScience listener Zackery Snaidman from Orlando in the US wants to know and presenter Marnie Chesterton has set out to find answers.

She starts at a hackathon in London, where she witnesses the birth and design of the UK’s new online court. And in Uganda, she hears how technology and social media is filling a crucial gap left by a shortage of human lawyers. Marnie is also surprised to discover a simple algorithm that regularly out-performs human judges in making bail decisions.

But could technology bring as many problems as it solves? Could seemingly ‘unbiased’ computers hide the prejudices of their makers? And more fundamentally: With our future liberty at stake, is the world ready to leave their fate in the hands of machines?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Anna Lacey

(Image: Digitized Lady Justice. Credit: Getty Images)

A billion people across the world smoke cigarettes, and many would agree it’s the hardest habit to quit. One such smoker, listener Sharif, emailed CrowdScience from Uzbekistan to ask if we could find out why giving up is so difficult. Marnie Chesterton travels to San Francisco to meet addiction experts and discovers how nicotine tricks smokers into thinking tobacco’s good for them. And we meet ex-smokers at a weekly therapy session aimed at retraining the brain.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Marijke Peters

(Image: Lit cigarette. Credit: Getty Images)

Earlier this year Crowdscience explored the question of time. Back then we were on a mission to uncover what the real time is and how we're able to measure time to ever greater degrees of accuracy. But as ever, the programme uncovered more questions than answers so presenter Anand Jagatia is back to try and find out where time comes from, why it runs forwards and not backwards, what happens to time in a black hole and does time even exist beyond our experience of it? We speak to Claudia Hammond, author of a book that reveals the mysteries of time perception and the man who defined time for the online Encyclopaedia Britannica, tells us if time really exists or not.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Rami Tzabar

(Image: Abstract clock image. Credit: Getty Images)

We're always up for a challenge on CrowdScience but this week’s question, which comes from an artist, tests our limits as we investigate the nature of thought itself – something that has puzzled scientists and philosophers since ancient times. Undeterred, presenter Nastaran Tavakoli-Far heads off to the Spanish island of Ibiza to visit listener Romanie in her painting studio and attempt to peer into the workings of her mind. As we explore the relationship between thought and language, why not join in with our experiments to discover if you’re thinking visually or verbally? We find out how language can affect thinking in surprising ways – why German speakers might see a bridge differently from Spanish speakers, how being bilingual can make you a better driver and even why some languages give their speakers a remarkable sense of direction.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk Presenter: Nastaran Tavakoli-Far Producer: Cathy Edwards

(Image: The Thinker a bronze sculpture by Auguste Rodin. Credit: Getty Images)

David in Bogota might have raised a few eyebrows in the CrowdScience office with his questions – can plants talk? And can they hear us talking to them? But actually scientists now know that plants do have the ability to communicate with the world around them to a much greater extent than previously thought. Some scientists even talk about plants being able to “hear” a hungry caterpillar or the sound of running water, while others argue that we should not anthropomorphise plants.

One underground communication network, affectionately dubbed the Wood Wide Web by scientists, is made of fungi that grow off the roots of plants. The network lets plants forge alliances, friendships and business partners.

But as we learn nothing is free in nature. In return for their haulage services, the fungi which make up the network siphons off some of the sugar produced during photosynthesis by the plants. Presenter Anand Jagatia goes foraging for answers in the woods together with fungal ecologists.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Louisa Field

(Image: Misty path running through woodland. Credit: Getty Images)

Back when Charles Darwin presented his theory of evolution by natural selection, French biologist Jean-Baptiste Lamarck suggested something different - that the changes you are exposed to during your lifetime can be passed on to future generations. By this theory, giraffes have long necks because, over generations, they have stretched them, reaching for leaves.

This theory became laughable when genes were discovered as the means of heredity. Lifestyle choices cannot be passed down in your DNA, or so we thought….But recently this idea has returned and a new field of biology has emerged called epigenetics – which looks at how the genes we inherit from our parents are controlled and modified by their life experience and the choices they made.

Marnie Chesterton meets the survivors of the Dutch Famine of World War Two, whose grandchildren show health effects from that event despite being born three generations after the starvation of 1944.

As the new field of epigenetics develops, does this mean Lamarck was right all along? Can your lifestyle be passed on to future generations and does this mean we need to rethink our traditional view of evolution?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presented and Produced by Marnie Chesterton

(Image: Grandmother, Mother and Daughter in a kitchen. Credit: Getty Images)

Listener Ros Allen wondered why it always seems to rain on her village but not the one a mile away. It’s all down to microclimates. CrowdScience explores the impact of microclimates on our lives, discovers how more rain can help an English tea plantation and reveals the deadly effect of the urban heat island. Marnie Chesterton also talks to a local project in New York City, the Cool Roofs Program, that aims to reduce the urban heat effect, helping to mitigate the impacts of climate change. But just how much of a difference can measures like this really make?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Marijke Peters

(Image: Women standing on the edge of a forest with an umbrella. Credit: Getty Images)

Trees transcend human generations – but are they the oldest living things on Earth? CrowdScience listener William from London, UK, got in touch to ask what the oldest tree or other organism on our planet is. Presenter Marnie Chesterton heads out to meet one of our older arboreal cousins to see how we can work out its age - without cutting it down to count the rings. But whilst certain individual trees can live for thousands of years, some that live in colonies can survive for much longer – perhaps up to 80,000 years old. Along the way, Marnie asks what other organisms contend for this title, what the word ‘oldest’ really means, and even ponders whether some creatures could actually be immortal.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Jen Whyntie

(Image: Ancient Bristlecone Pine Forest. Credit: Getty Images)

You don’t have to be a “super-recogniser” to know that human facial features are extremely varied. Just look around you. Yet look at a most other animals and you’d find it hard to tell individuals apart. So why are human faces so diverse?

We’ll also be finding out why salt tastes salty (warning: lots of spitting and gargling ahead) and one listener wants to know what would happen if one of the key ocean current systems, the North Atlantic Conveyer, slowed down or stopped altogether. Presenter Marnie Chesterton heads to the beaches on the West Coast of Scotland in search of answer. Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk Presenters: Marnie Chesterton and Geoff Marsh Producers: Laura Hyde and Jennifer Whyntie

Childbirth is different for everyone. Depending on who you ask, it’s one of life’s greatest and worst experiences - and can be anything from traumatic and excruciating to life-affirming and spiritual. But what pretty much every mother will agree on is that it hurts. But why is such a fundamental aspect of life so painful? And why do some women find it worse than others?

Presenter Gareth Barlow – who doesn’t expect to be giving birth ever – goes on a quest to understand the experience of female labour pain and why evolution hasn’t given women an easier ride. He discovers the latest research into the nature and experience of pain and whether the idea of male/female pain thresholds, is a real thing. We also hear from CrowdScience listeners about their own experiences, and find out if having a supportive birth partner can help bringing new life into the world that little bit easier.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Gareth Barlow Producer: Anna Lacey

(Image: New born baby with mother. Credit: Getty Images)

Even if you spent your entire life on a plane, the chances are you’d never crash – commercial air travel is remarkably safe. But after hearing about a recent air tragedy, two brothers in Kampala wondered if commercial airplanes could ever have ejector seats – like fighter jets do - to give passengers a last option for escape.

We meet 98-year-old John Oliver “Jo” Lancaster, one of the first people ever to eject out of a plane, and discover the seemingly insurmountable barriers to fitting ejector seats into passenger jets. And we find out that an awful lot of work goes into making flying as safe as it is, as we visit an air accident investigation lab, practise an emergency exit from a passenger cabin and deal with a multiple engine failure …in a plane simulator.

But are any safety ideas as radical as ejector seats on the horizon? We assess a controversial design that would parachute the entire passenger cabin down to earth should the worst happen.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Cathy Edwards

(Image: Person blasting out of a plane cockpit on an ejection seat Credit: Martin-Baker Aircraft Company Ltd)

Sex is responsible for the large variety of life on earth. Without the two sexes there is no sexual reproduction which means no shuffling of the genetic make-up – and no survival in a changing environment. But why do we have two sexes in the first place and does nature determine your sex? It’s with these questions and more that listener Du from Singapore persuaded the CrowdScience team to investigate the weird and wonderful world of sex. You might think that Nature would have standardised something as important as ensuring the continuation of the species. Far from it – species do sex in many different ways – some stranger than others.

Presenter Marnie Chesterton unpicks the zoological oddities of sex and along the way learns about her own sex chromosomes. We also meet an unlikely bird keeper, who is the proud owner of a female duck that is morphing into a male. Will her boyfriend, a male mandarin duck, mind the change?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Louisa Field

(Image: Male and female mandarin ducks. Credit: Getty Images)

Biometrics are being used everywhere to recognise us. On this edition of CrowdScience we try out the tech that tells us apart. We find out just how unique our irises are and meet a man who can pick people out from a crowd of thousands just by analysing the way they walk.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Marijke Peters

(Image: Fingerprints being looked at under a magnifying glass. Credit: Getty Images)

Our planet is getting rather cosy. In just over 200 years, the global population has grown from 1 billion to almost 7.5 billion – and the best estimates suggest it’s going to keep on increasing. But just how far can it go? When will we reach ‘peak human’? That’s what CrowdScience listeners Alan Donaldson and Francoise Brindle want to know: what’s the latest estimate for how many people the Earth can support?

It’s a question that’s been bothering some of the world’s greatest thinkers for hundreds of years, and now presenter Marnie Chesterton goes on her own quest for answers. Her journey takes her through the technology and innovation that keeps our growing population alive, and she looks to Dhaka, Bangladesh, to find out what a more densely populated world might feel like. But are there signs that things are already levelling off? And could improving photosynthesis allow populations to grow without destroying the environment?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Anna Lacey

(Image: People on busy street. Credit: Getty Images)

Mining asteroids, moons or even other planets has remained firmly within the realm of science fiction. But as certain elements become increasingly scarce on Earth, private companies and even nation states are looking to make extra-terrestrial mining a reality. Presenter Marnie Chesterton heads to an Earth-based mine in Scotland to see just how tricky space mining could be, and what possibilities it holds. On the way she discovers what laws govern this new far frontier, and hears from a space prospector who already has designs on key sites for exploration. Could our solar system's asteroids really become self-fuelling gas stations for spaceships?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Jen Whyntie

(Image: Double the Rubble Artist Concept. Credit: NASA)

For most people the idea of chewing on a caterpillar or tucking into a tarantula is pretty unpalatable. Yet according to the United Nations, some two billion people around the world consume insects regularly. This prompted World Service listener Saman from Pakistan to ask the BBC CrowdScience team “are insects a serious food source?”

To tackle this question, we head to Burkina Faso in West Africa where shea caterpillars are an important part of the local diet in a place where food security is low and malnutrition is high.

Here we follow scientist Charlotte Payne as she tries to crack the tricky science behind the caterpillar’s life cycle and see how local entrepreneur Kahitouo Hien is trying to change lives and reduce malnutrition with edible caterpillars.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Anand Jagatia Producer: Louisa Field

(Image: Bowl of cooked Caterpillars. Credit: BBC/Anand Jagatia)

Why do we have so many accents - even when we’re speaking the same language? What's happening in our brains and mouths to make us sound so different from each other? This week’s question from listener Amanda takes CrowdScience to Glasgow in Scotland: home to one of the most studied - and distinctive - accents of English.

Along the way we visit a voice coach to try and learn a Texan accent, use ultrasound to see what different sounds look like inside our mouths and find out how a brand new dialect was formed when many accents collided in New Zealand.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Nastaran Tavakoli-Far Producer: Cathy Edwards

New Zealand Mobile Unit recordings courtesy of Ngā Taonga Sound & Vision

(Image: A mouth screaming white letters. Credit: Thinkstock)

Do your joints ache when it's raining? Are you blighted with headaches when the wind picks up? If the answer’s yes then you're definitely not alone. People have been linking their heath to the weather since the time of the Ancient Greeks - but is the effect real?

CrowdScience heads for the hills and gets closer to the clouds to have a go at answering this 2,500 year old question.

People who believe they’re sensitive to the weather aren’t always taken seriously. But presenter Datshiane Navanayagam hears about the latest ground-breaking experiments that show there's a lot more to it than folklore. And if you've ever wondered why you're particularly prone to aches and pains in the winter, the answer could all be in your genes.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Datshiane Navanayagam Producer: Anna Lacey

(Image: Man looking up to grey clouds. Credit: Thinkstock)

Can we really live on Mars? Or exist in a virtual world? And why does movie science sometimes have us shouting at the screen? Our panel of scientists and sci-fi experts reveal all in this special edition of CrowdScience recorded live at the South by Southwest Conference & Festivals in Austin, Texas, USA. To tackle all of our listeners’ questions about science in film, presenter Marnie Chesterton is joined by a team of specialists.

Prof Polina Anikeeva is an MIT materials scientist and engineer whose research focuses on developing devices that work directly with the human nervous system. A sci-fi fan, Prof Anikeeva knows just how realistic brain-computer interface movies such as Avatar and The Matrix are.

Former NASA astronaut Dr Mae Jemison is a medical doctor, engineer, educator and entrepreneur, and the first African-American woman to go into space aboard the shuttle Endeavour in 1992. She is leading the 100 Year Starship Project, which aims to take humans beyond our solar system by 2112.

Prof Clifford Johnson is a theoretical physicist at USC whose work leads him to think about space-time, black holes, and extra dimensions, making him a regular contributor to documentaries about science and sci-fi films.

Rick Loverd is Program Director of The Science & Entertainment Exchange at the National Academy of Sciences, which inspires better science in Hollywood by introducing entertainment professionals to scientists and engineers. The Exchange has consulted on movies including Star Trek: Into Darkness, Iron Man 2 and Thor.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Jen Whyntie

Audio clip from Gravity Warner Bros. Pictures Director: Alfonso Cuarón

Audio clip from Interstellar Warner Bros. Pictures and Paramount Pictures Director: Christopher Nolan

(Image: Matt Damon in The Martian. Credit: Getty Images) (Image: Zoe Saldana in Avatar. Credit: Getty Images) (Image: Matthew McConaughey in Gravity. Getty Images)

The human race is getting fatter. But is it our fault? There are a whole host of factors influencing our weight - how many of them can we control?

CrowdScience discovers how factors like our environment and our genes can tip the scales in the wrong direction.

We visit an apartment complex originally designed for Olympic athletes, to see if people can get fitter just by living there. And from a brand new menu plan for overweight Mumbai police, to hormone injections that stop you getting hungry, CrowdScience asks the experts what we can do if we’ve been dealt a bad hand when it comes to our weight.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Cathy Edwards

(Image: Women and a Man standing next to each other holding hands. Credit: ThinkStock.)

Trees take in carbon dioxide but they also convert some of the toxic gases in our air. How much help can trees give us in fighting air pollution and could where we plant them make an even bigger difference? Crowdscience reports from the side of some busy roads on how canopy coverage may be part of the answer. At a lab in Louisiana one scientist is putting oak leaves through their paces to find out how effective they are at cleaning our air.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Marijke Peters

(Image: Trees in a forest Credit: Julian Stratenschulte/Getty Images)

Our listener Joseph’s question might sound more sci-fi than science show. But as Marnie Chesterton discovers, robots have already entered the realm of medicine and are likely to become more important in the future. A visit to the operating theatre at the University College Hospital in London together with surgeon Caroline Moore reveals that robots take the scalpels out of surgery by letting surgeons treat patients with prostate cancer without having to make a single cut. And chatting to Molly the robot alongside Dr. Praminda Caleb-Sully at Bristol Robotics Laboratory, Marnie discovers that robots could be the helping hand we need to look after a growing elderly population.

Machines win when it comes to data-processing. But what about empathy and intuition? Such characteristics would require machines to reach a level of artificial intelligence (AI) which critics say is decades away. The sceptics insist humans will always play a key role in healthcare. But others suggest that not only will AI change everything – but technology will one day eliminate the need for us to go to the doctor ever again.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

(Image: Three Robots on Display at the Science Museum in London. Credit: Carl Court/Getty Images)

Presenter: Marnie Chesterton Producer: Louisa Field

A few weeks ago, CrowdScience asked if it pays to be nice. We found that the answer is yes – if you’re a human. But if being social is so great, why aren’t all animals doing it?

That’s what our US listener Tony wants to know. After listening to ‘Does it Pay to be Nice?’ he rightly pointed out that cats lead mostly solitary lives - but don’t seem any worse off for it. So why have they taken this path? And are they any less advanced than a social species as a result?

Presenter and naturalist Tim Cockerill heads to the rainforests of Madagascar in search of answers. After lots of trekking through the undergrowth, he finds out why so many animals choose group living and what’s different about cats to make them go it alone.

But does it matter which way of life an animal takes? Tim discovers that for humans at least, being social has given us much more than we imagine.

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Tim Cockerill Producer: Anna Lacey

(Photo: Cat lying on floor. Credit: Getty Images)

Death is one of life’s few certainties – or is it? To answer listener Pratibha’s question from New Delhi, India, presenter Marnie Chesterton asks medical and scientific experts if there is any evidence that humans could somehow come back into existence after their demise. We start at the end, by asking just what death is – and it turns out to be perhaps surprisingly complicated, especially if cold temperatures are involved. As another listener, Camilla, from Washington DC, USA points out, there are some animals that can become totally frozen over winter and return to life in spring. How does this happen, and could it have implications for the idea of deep-freezing humans – known as cryogenic preservation? Alternatively, if entire bodies might prove difficult to save, could we download our brains’ contents for later reboot instead? It sounds like science fiction, but a global network of scientists are pursuing the goal of cybernetic immortality: uploading our minds to an artificial brain in a robot avatar. Marnie heads to a brain-computer interface lab where she gets wired up to control a computer game by thinking, and discovers just how difficult it is to export thought, and how much we still have to learn about our brains. Could the way to cheat death ever be digital?

Do you have a question we can turn into a programme? Email us at crowdscience@bbc.co.uk

Presenter: Marnie Chesterton Producer: Jen Whyntie