Episodes

  • Thanks to a ban on several hazardous pesticides Sri Lanka has seen a massive reduction in deaths from pesticide poisoning, and the World Health Organisation is recommending other countries should follow this example.

    As Health Correspondent Matthew Hill discovers, hospitals which used to deal with many pesticide related deaths are now seeing fewer cases, and more survivors. However, a lack of mental health services means, for many in rural communities, taking pesticides is still a way of drawing attention to a variety of personal issues - sometimes with tragic consequences.

    Image: Rural pesticide shop, Sri Lanka (Credit: BBC)

  • “Nature red in tooth and claw”. “Dog eat dog”. “Fighting for survival". You may well think that the natural world is one dangerous, violent, lawless place, with every creature out for itself. And it can be, but it can also be peaceful, democratic and compassionate.

    Lucy Cooke seeks out the animal communities that adopt a more peaceful and democratic way of life and asks why it works for them. Despite being fierce predators, African wild dogs are cooperative and compassionate within their packs, and they actually hold democratic votes on hunting decisions – one sneeze for yes, two sneezes for no! They are among the most effective predators in the world. They use extraordinary cooperation and teamwork to pursue, overhaul and bring down their prey. As a result 80% of their hunts end successfully, compared to lions' at 10%. This is nearly all a result of their pack coordination. They are also surprisingly non-aggressive; they don’t fight over food but instead beg to indicate their wish to eat. Adults will allow younger pack members to eat before them. And the African wild dogs are not alone: such societies are also common in insects, other mammals, and birds, but exist even in simple species like amoebas.

    But what is the evolutionary advantage of this group cohesion? Why when nature selects for not just the individual but for the selfish gene, does it pay to be part of a complex social group? Lucy discovers that when the benefits of group-living outweigh the costs, it’s very much advantageous – when 10 pairs of eyes are better at spotting predators and pack strategies mean far more successful kills in a hunt, or when grooming not only strengthens bonds, but it also gets rid of your ticks and fleas. She also explores the different strategies of the highly complex social animals – the Great Apes – and asks whether Bonobos are truly the lovers and Chimpanzees the fighters?

    This all touches on the complex social interactions we have as humans. We can be peaceful and we can be violent and war-like, and like every species, individual variation and circumstances can tip the balance of our behaviour. But anthropologist Agustin Fuentes questions the belief that humans are at their core violent, aggressive, and oversexed. Are these behaviours part of our genetic heritage? What can biology, evolution, and behaviour tell us about peace and aggression in everyday life?

    Picture: African Hunting Dogs by Paul F Donald

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  • Bigger is better, right? An ancient lore in biology, Cope's rule, states that animals have a tendency to get bigger as they evolve. Evolution has cranked out some absolutely huge animals. But most of these giants are long gone. And those that remain are amongst the most threatened with extinction. Scientists now believe that while evolution favours larger creatures, extinction seems to favour the small.
    If you look at mammals, at the time of the dinosaurs, they were confined to rodent-sized scavengers living on the periphery. But 66 million years ago, the dinosaurs went and allowed the mammals to evolve into some really big creatures - 30 metre long blue whales, the ten tonne steppe mammoth and a giant ground sloth that looked a bit like a hamster but was the size of an elephant with enormous hooks for hands. Now, only the blue whale remains and these have been shown to have shrunk to half the size of their Pleistocene ancestors. So is it better to be small? Smaller animals need fewer resources and smaller territories. With the planet in such peril - are more animals going to start shrinking? Well, perhaps...new research shows that in 200 years' time, the largest mammal might be the domestic cow. And of course the most successful organisms, in terms of biomass, on the planet are the smallest. Zoologist, Lucy Cooke examines the science of being small, and why size matters.

    Producer: Fiona Roberts

    (Photo: Honeybee sitting on a flower. Credit: Dr Paul F Donald)

  • Lucy Cooke sets out to discover why honesty is almost certainly not the best policy, be you chicken, chimp or human being. It turns out that underhand behaviour is rife throughout the animal kingdom, and can be a winning evolutionary strategy. From sneaky squid, to cheating cuckoos, some species will resort to truly incredible levels of deception and deviousness to win that mate, or get more food. And when it comes to social animals like we humans, it turns out that lying, or at least those little white lies, may be the social glue that binds us all together.

    Lucy heads to the RSPB cliffs at Bempton, with Professor Tim Birkhead to discover why so many bird species appear to be such proficient deceivers, as well as visiting the very crafty ravens at The Tower of London. She speaks to psychologist Richard Wiseman about how to spot when someone is lying, and finds out whether she is any good at it. In fact, can we trust any of what she says in this documentary at all?

    Presenter Lucy Cooke
    Producer Alexandra Feachem

    Main image: Raven Credit: Dr Paul F Donald

  • Professor Deborah Bowman reveals how a diagnosis of cancer has transformed her view of medical ethics and what it means to be a patient.

    As Professor of Ethics and Law at St George's, University of London, Deborah has spent the past two decades teaching and writing about medical ethics, the moral principles that apply to medicine.

    It's taken her down countless hospital corridors, to the clinics and the wards where medical ethics plays out in practice, behind closed doors, supporting healthcare practitioners and their patients to negotiate uncertainty and conflict.

    This is the field of clinical ethics and, each time, the 'patient' has been central to her response.

    Yet in the autumn of 2017, everything changed. Deborah was diagnosed with breast cancer and it signalled the beginning of her undoing, not just personally but professionally too, playing havoc with what she thought she knew about clinical ethics.

    Patient autonomy - literally 'self-rule'- is one of its cornerstones - a patient's right to make decisions about their healthcare. So what does autonomy mean if the 'self', she thought she knew, was so changeable and confusing?

    Deborah returns to the Royal Marsden Hospital where she is a patient, to explore this - with both her personal and professional hats on.

    Producer: Beth Eastwood

    Main Image: Deborah Bowman. Copyright: Deborah Bowman

  • Matthew Cobb, Professor of Zoology at the University of Manchester, explores the hidden world of prestige, profits and piracy that lurks behind scientific journals.

    Each year, hundreds of thousands of articles on the findings on research are published, forming the official record of science. This has been going on since the 17th century, but recently a kind of war has broken out over the cost of journals to the universities and research institutions where scientists work, and to anyone else who wants to access the research, such as policy makers, patient support groups and the general public.

    Traditionally journals charge their readers a subscription, but since the start of the 21st century there's been a move to what's called open access, where the authors pay to get their articles published but anyone can read them, without charge. In Europe Plan S has called for all research funded by the public purse to be open access, by 2021. If and when this is implemented it could have downsides on learned societies who depend on income from journal subscriptions to support young researchers and on scientists in the less developed world.

    Some universities, and even countries, have recently refused to pay the subscriptions charged by some of the big science publishers. This has led to some scientists using a service run by a Russian hacker, which has effectively stolen the whole of the scientific literature and gives it away, free, on the internet.

    Matthew Cobb looks back at how the scientific publishing industry got to its current state and asks how it could change. He argues that scientists themselves need to break their addiction to wanting their articles to appear in a few well known journals, and instead concentrate on the quality of their research.

  • Dr Erica McAlister, of London's Natural History Museum, talks to Jim Al-Khalili about the beautiful world of flies and the 2.5 million specimens for which she is jointly responsible.

    According to Erica, a world without flies would be full of faeces and dead bodies. Unlike, for example, butterflies and moths, whose caterpillars spend their time devouring our crops and plants, fly larvae tend to help rid the world of waste materials and then, as adults, perform essential work as pollinators. Yet they are rather unloved by humans who tend to regard them as pests at best and disease vectors at worst.

    2019 is international Year of the Fly, and dipterists and entomologists around the world are working to raise the profile of the many thousands of species so far known to science.

    Erica tells Jim about her work in the museum, cataloguing and identifying new species either sent in from other researchers or discovered by her and her colleagues on swashbuckling trips around the world. Modern gene sequencing techniques are revealing new chapters in the life histories of species, and her collection of 300 year old dead flies continues to expand our knowledge of how the world works.

    Perhaps in the future, she argues, we will all be eating pasta and bread made from fly-larvae protein, or using small tea-bag like packets of maggots in our wounds to clean out gangrenous infection.

  • When Sir Richard Peto began work with the late Richard Doll fifty years ago, the UK had the worst death rates from smoking in the world. Smoking was the cause of more than half of all premature deaths of British men. The fact that this country now boasts the biggest decrease in tobacco-linked mortality is in no doubt partly due to Doll and Peto's thirty year collaboration.

    Professor of Medical Statistics and Epidemiology at the University of Oxford and until last year co-director of the Clinical Trial Service Unit with Professor Sir Rory Collins, Richard Peto pioneered "big data", setting up enormous randomised clinical trials and then, in a novel approach, combining results in what became known as meta-analyses, amassing unequivocal evidence about how early death could be avoided. He showed how asprin could prevent heart attacks and how the oestrogen-blocking drug tamoxifen really did affect survival rates for breast cancer patients.

    Results on paper saves lives in the real world, he says, and he's famous for catchphrases like: "death in old age is inevitable, but death before old age is not" and "you can avoid more deaths by a moderate reduction of a big cause, than by a big reduction in a small cause" as well as "take the big numbers seriously".

    One of the world's leading epidemiologists, Richard Peto's landmark study with Alan Lopez at the World Health Organisation predicted that a billion people would die from diseases associated with tobacco this century, compared to a hundred million killed by tobacco in the 20th century. The chilling message galvanised governments around the world to adopt anti-smoking policies. And Professor Peto's studies about smoking cessation ("smoking kills, stopping works") provided the public health evidence needed to encourage smokers that, however long they had smoked for, it was always worth quitting.

  • James Lovelock is one of the most influential thinkers on the environment of the last half century. His grand theory of planet earth, Gaia, the idea that from the bottom of the earth's crust to the upper reaches of the atmosphere, planet earth is one giant inter-connected and self-regulating system, has had an impact way beyond the world of science.

    As James Lovelock, celebrates his hundredth birthday (he was born on 26th July 1919) he talks to science writer Gaia Vince about the freedom and frustrations of fifty years spent working outside the scientific establishment. While working at the National Institute for Medical Research he invented the Electron Capture Detector - an exquisitely sensitive device for detecting the presence of the tiniest quantities of gases in the atmosphere and led to a global ban on CFCs. It also took him to NASA and via designing a detector to look for life on Mars gave him the idea of Gaia.

    Public interest in Gaia proliferated after the publication of his first book Gaia: a new look at life on earth in 1979; but the scientific community remained highly sceptical. For decades Gaia was ignored, dismissed and even ridiculed as a scientific theory. To this day, evolutionary biologists, in particular, take issue with the notion of a self-regulating planet though some are coming round to the idea.

    Gaia Vince talks to earth system scientists Professor Andrew Watson and Professor Tim Lenton of Exeter University who have both championed the Gaia theory, and to Professor Ford Doolittle of Dalhousie University, an evolutionary biologist who has changed his mind about the theory.

    Producer: Deborah Cohen

    Picture: British scientist James Lovelock poses on March 17, 2009 in Paris. Credit: Jacques Demarthon / AFP / Getty Images.

  • The Moon rush is back on. And this time it’s a global race. The USA has promised boots on the lunar surface by 2024. But China already has a rover exploring the farside. India is on the point of sending one too. Europe and Russia are cooperating to deliver more robots. And that’s not to mention the private companies also getting into the competition. Roland Pease looks at the prospects and challenges for all the participants.

    (Image caption: Chinese lunar probe and rover lands on the far side of moon. Credit: CNSA via EPA)

  • Pain, as we know, is highly personal. Some can cope with huge amounts, while others reel in agony over a seemingly minor injury. Though you might feel the stab of pain in your stubbed toe or sprained ankle, it is actually processed in the brain.

    That is where Irene Tracey, Nuffield Professor of Anaesthetic Science at Oxford University, has been focussing her attention. Known as the Queen of Pain, she has spent the past two decades unravelling the complexities of this puzzling sensation.

    She goes behind the scenes, as it were, of what happens when we feel pain - scanning the brains of her research subjects while subjecting them to a fair amount of burning, prodding and poking.

    Her work is transforming our understanding, revealing how our emotions influence our experience of pain, how chronic pain develops and even when consciousness is present in the brain.

    Producer: Beth Eastwood

  • Physicist Paul Davies talks to Jim al-Khalili about the origin of life, the search for aliens and the evolution of cancer.

    Paul Davies is interested in some of the biggest questions that we can ask. What is life? How did the universe begin? How will it end? And are we alone? His research has been broad and far-reaching, covering quantum mechanics, cosmology and black holes. In the 1980s he described the so-called Bunch-Davies vacuum - the quantum vacuum that existed just fractions of a second after the big bang - when particles were popping in and out of existence and nothing was stable.

    As the chair of SETI (the Search for Extra-Terrestrial Intelligence) Post Detection Task Group, he’s the person responsible for announcing to the world when we make contact with aliens. He’s now Regents Professor of Physics at Arizona State University in the American south west where he runs research groups studying the evolution of cancer and the origins of life.

    Paul Davies talks to Jim al-Khalili about how he applies the principles of physics to these big questions and about how he has worked closely with religious thinkers.

    Producer: Anna Buckley

  • In the 1950s a batch of polio vaccine in the US was made badly, resulting in 10 deaths and the permanent paralysis of 164 people. Paul Offit, a paediatrician in Philadelphia, says the disaster did not turn people away from vaccines. He believes that current vaccine hesitancy needs to be tackled online - where fake news spreads quickly.

    The German state of Brandenburg wants to make pre-school vaccinations compulsory - like neighbouring France and Italy - because immunisation rates there dropped to 73%. But some doctors believe busy parents can instead be gently persuaded to take up vaccines.

    Perhaps this is where psychological research can play a role. Sander van der Linden, Director of the Cambridge Social Decision Making Lab in the UK, is working on an online game which "inoculates" people against fake news - by showing them how they can be manipulated online. He says the effects last about 6 weeks - so a "booster" may be necessary.

    Head of the Vaccine Confidence Project Heidi Larson applauds 18 year old American Ethan Lindenberger who decided to get vaccinated despite his own mother's anti-vax views which he says she got from reading church and internet anti-vaccination groups rather than from the medical profession.

    Producer: Paula McGrath

    Picture: A vial of measles, mumps and rubella vaccine and an information sheet, Boston Children's Hospital in Boston, Massachusetts February 26, 2015. Credit: Reuters / Brian Snyder / File Photo

  • Global attitudes towards vaccinations are revealed in the Wellcome Trust’s Global Monitor survey. Our guide through the new data is Heidi Larson, Professor of Anthropology, Risk and Decision Science at the London School of Hygiene and Tropical Medicine who also leads the Vaccines Confidence Project. She says the most vaccine-sceptical country is France – because of past scares around different vaccines.

    The success of vaccines means people have forgotten how measles can be fatal – and parents are now influenced by scare stories about vaccines. More than half of the 1,000 recent cases of measles in the US have been in the Orthodox Jewish community in New York city. We hear from some of the parents who still don’t vaccinate and from a family doctor about trustworthy sources of information.

    Things couldn’t be more different in Madagascar where more than 1200 children have died from measles and parents walk for miles to have their children immunised. Half the country’s children are malnourished – which can increase the risk of complications if they catch measles. Vitamin A supplements are being given to help the immune system to work properly.

    Next week on Discovery – could compulsory vaccines or a more subtle, psychological approach help to address vaccine hesitancy?





    Producer: Paula McGrath


    Photo: Children walk past a sign advising about a measles outbreak in the Brooklyn Borough of New York.
    Credit: Reuters)

  • "What happens to the human voice as we age? If I hear a voice on the radio, I can guess roughly how old they are. But singer's voices seem to stay relatively unchanged as they age. Why is this?" All these questions were sent in by Jonathan Crain from Long Island in New York.

    Doctors Adam Rutherford and Hannah Fry discover how the human voice is produced and listen to how our voice sounds when it emerges from our vocal cords. Acoustic engineer Trevor Cox, author of Now You're Talking, explains why German and French babies have a different accent. And neuroscientist Sophie Scott describes what happens when boys' voices break, and why a similar thing can happen to women during the menopause.

    Finally, our voices often change dramatically in later life, as demonstrated by comedy impressionist Duncan Wisbey. Expect cameos from David Attenborough, Dumbledore and Paul McCartney.

    Bird Song

    "Winter is finally over and the birds are all singing their hearts out at dawn. What is all the noise about? And why are some songs so elaborate?" asks Tony Fulford from Cambridgeshire in the UK.

    We find out how birds produce multiple notes at once, which one has the widest repertoire of songs, and why males like to show off quite so much. Plus, we talk to researcher Lauryn Benedict about the project which aims to solve the mystery of why female birds sing.

    Featuring interviews with RSPB president and nature presenter Miranda Krestovnikoff, and world-renowned birdsong expert and sound recordist, Don Kroodsma from the University of Massachusetts. TV archive courtesy of The One Show, BBC TV.

    Please send your cases for consideration for the next series to curiouscases@bbc.co.uk.

    Presenters: Adam Rutherford, Hannah Fry
    Producer: Michelle Martin.

    (Photo: Eurasian Wren (Troglodytes troglodytes). Credit: Getty Images)

  • “Is anything in the Universe truly infinite, or is infinity something that only exists in mathematics?” This question came from father and son duo from Edinburgh in Scotland, Tom and Sorely Watson.

    First, we investigate the concept of infinity in mathematics with a story of mathematics, music and murder from Steven Strogatz from the Cornell University.

    Did you know that there are some infinities that are bigger than others? We discuss the mind-bending nature of infinity with mathematician Eugenia Cheng, author of Beyond Infinity.

    Next we turn to physics to see if we can find something in the Universe that is truly infinite.

    Theoretical physicist Sean Carroll from Caltech University discusses the infinitely small inside subatomic particles. Plus cosmologist Andrew Pontzen from University College London travels into the heart of a black hole to see if we can find a something that is infinitely dense.

    But if we’re looking for something that is infinite, how about the Universe itself? We find out how physicists measure the shape of the Universe, with the help of an orange and a game of Asteroids. However, if the Universe is not infinite, and it has an edge, what is on the other side?

    Presenters: Hannah Fry, Adam Rutherford
    Producer: Michelle Martin

    (Photo: The Infinity symbol in an exploding cloud of data. Credit: Wigglestick/Getty Images)

  • 4/6 Part 1: Déjà vu

    "Do we know what causes déjà vu?" asks Floyd Kitchen from Queenstown in New Zealand.

    Drs Rutherford and Fry investigate this familiar feeling by speaking to world-leading reseacher Chris Moulin from the University of Grenoble in France and memory expert Catherine Loveday from Westminster University. Plus, they find out why early investigations classed déjà vu as a type of paranormal phenomenon.

    For most of us, it's a fleetingly strange experience, but for some people it can become a serious problem. Lisa from Hulme in Manchester started experiencing déjà vu when she was 22 with episodes that could last all day. The origin of her déjà vu has been the key to helping psychologists investigate its cause.

    Part 2: Randomness

    "Is anything truly random, or is everything predetermined?" asks Darren Spalding from Market Harborough.

    Hannah and Adam go in search of random events, from dice throws to lava lamps. Can we predict the outcome of any event?

    "How do computers manage to pick random numbers?" asks Jim Rennie from Mackinaw in Illinois. Random numbers are vital for things like cyber security and banking. But true randomness is surprisingly hard to produce, as the team discover.

    Joining them for this case we have a random selection of experts: mathematician Colva Roney-Dougal, technology journalist Bill Thompson, Science Museum Curator Tilly Blyth and quantum physicist Jim AlKhalili.

    Presenters: Hannah Fry, Adam Rutherford
    Producer: Michelle Martin

    Main Image: A fan of the New York Yankees holds up a sign which reads "It's Deja Vu" at the Yankee Stadium, New York City 29 Oct 2009. Credit: Jed Jacobsohn / Getty Images

  • 3/6 In this instalment of The Curious Cases of Rutherford & Fry, Hannah and Adam boldly go in search of scientists who are hunting for ET, spurred on by questions sent in by listeners across the globe, from Australia to Columbia.

    They start by asking how we define life and why we are obsessed with finding it on Mars. Should we be looking further out in the Solar System, and could we find space squid on the icy moon Europa?

    When it comes to intelligent life we may have to scout even further into the Universe. But what are the chances of finding complex life in the cosmos? And where might it live?

    Featuring astronomer Seth Shostak from the SETI Institute in California, planetary scientist Monica Grady from the Open University, exoplanet hunter Sara Rugheimer from the University of St Andrews and zoologist Matthew Cobb from Manchester University.

    Send your Curious Cases for consideration in to curiouscases@bbc.co.uk

    Presenters: Hannah Fry, Adam Rutherford
    Producer: Michelle Martin.

    Main Image: This image obtained from NASA on November 25, 2013 shows several images that were taken by the Hubble Space Telescope of the spiral NGC 4921 from the Coma Cluster of Galaxies. Copyright: NASA / Hubble / ESA / Handout

  • 2/6 "How fast can a human run and would we be faster as quadrapeds?" This question flew in via Twitter from Greg Jenner.

    Is there a limit to human sprinting performance? In this episode we investigate the biomechanics of running, statistical trends in human performance and which kind of monkey runs the fastest.

    But first, an experiment. Due to some spurious and possibly fictional injuries, neither Hannah nor Adam are fit enough to take part in a sprint trial at the University of Bath. So long-suffering Producer Michelle steps up to the challenge and into the starting blocks. Not known for her love of athletics, or exercise of any sort, how will she fair in the ultimate speed test?

    Biomechanist Peter Weyand from Texas discusses the role of different muscle types in speed versus endurance. Sports scientist Polly McGuigan reveals why Usain Lightning Bolt is still the fastest man in the world. And Prof of Sports Engineering Steve Haake reveals how fast a man can run like a monkey.

    "Why do people experience pain differently when they go through the same event?" asks Claire Jenkins from Cwmbran in Wales.

    Professor of Pain Research, Irene Tracey, welcomes Adam in to the room she calls her 'Torture Chamber'. Burning, electrocuting, lasering and piercing are all on the menu, but which will hurt the most?

    Hannah speaks to Steve Pete from Washington who has a rare genetic condition which means he does not feel pain. For chronic sufferers, this sounds like heaven, but a life without pain has brought untold suffering to him and his family, including the tragic story of his brother, Chris.

    We look at how the body creates pain, why some people feel it more than others, and how this knowledge could help scientists treat pain more effectively in the future.

    Presenters: Hannah Fry, Adam Rutherford
    Producer: Michelle Martin

    (Photo: A runner beats the pain to make it over the finishing line in the Hong Kong Marathon 12 February 2006. Credit: Martin Chan/South China Morning Post/Getty Images)

  • 1/6 "We play many musical instruments in our family. Lots of them produce the same pitch of notes, but the instruments all sound different. Why is this?" asks Natasha Cook aged 11, and her Dad Jeremy from Guelph in Ontario, Canada.

    In this new series of The Curious Cases of Rutherford and Fry, Hannah and Adam are joined by the Curious Cases band - Matt Chandler and Wayne Urquhart - to play with today's question.

    Bringing the science we have acoustic engineer and saxophone player Trevor Cox. Plus materials expert Zoe Laughlin demonstrates a selection of her unusual musical creations, including a lead bugle, a glass bell and a spruce tuning fork.

    Presenters: Adam Rutherford, Hannah Fry
    Producer: Michelle Martin

    Main image: 1-25 Wind instruments, 26-34 percussion instruments, Egypt, engraving by Duhamel from Description of Egypt, or the collection of observations and researches which were made in Egypt during the expedition of the French Army), Etat moderne, Planches, Volume II, Plate PlCC, Imprimerie Imperiale, 1817, Paris. Credit: De Agostini Editorial / Getty Images