The Life Scientific

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. Producer: Alex Mansfield

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. Producer: Fiona Hill

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 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

Throughout the history of planet Earth, the element carbon has cycled between the atmosphere, the oceans and the biosphere. This natural cycle has maintained the amount of carbon dioxide in the atmosphere and has allowed life to exist for billions of years. Corinne Le Quéré is a climate scientist who keeps track of where the carbon comes from and where it goes – all on a truly global scale. Corinne Le Quéré is the founder of the Global Carbon Budget, which each year reports on where carbon dioxide is being emitted and where it is being absorbed around the world. More specifically, she studies the relationship between the carbon cycle and the earth’s climate, and how it is changing. Corinne is Professor of Climate Change Science at the University of East Anglia. After a degree in physics in her native Canada she became aware of the importance of how carbon moves around the planet and the way it controls the Earth’s climate. This took her to studying meteorology and oceanography and in particular a fascination with the role of the huge Southern Ocean in trapping and holding onto carbon. She talks to Jim al-Khalili about modelling how carbon moves around the earth and how she communicates the latest research to the public.