Discovery

BBC Health and Science correspondent James Gallagher explores the latest research into how our second genome, the vast and diverse array of microbes that live on and in our bodies, is driving our metabolism and our health and how we can change it for the better.In this second episode he explores how researchers are uncovering a vital relationship between the healthy bugs we accumulate in our gut and our immune system . We have over the past 50 years done a terrific job of eliminating infectious disease. But in we've also done the same to many good bacteria and as a result we're seeing an enormous and terrifying increase in autoimmune disease and in allergy. Could correcting our encounters with bugs at birth, and in the first few month of life set us on a path of good health? And in if in later life the delicate balance between our body and bugs gets skewed, leading to inflammatory diseases such as irritable bowel syndrome or frailty in old age, how can this be rectified?Illustration by Katie HorwichProducer: Adrian Washbourne

Are we on the cusp of a new approach to healthy living and treating disease? BBC Health and Science correspondent James Gallagher explores the latest research into how our second genome, the vast and diverse array of microbes that live on and in our bodies, is driving our metabolism and our health. Recent DNA analysis by the Human Microbiome Project detailed the vast and diverse array of microbes in and on our body - bacteria, archaea, fungi and viruses. It has been described as our second genome - a source of huge genetic diversity, a modifier of disease, an essential component of immunity, and an "organ" that influences not just our metabolism but also our mental health. Unlike the human genome which is fixed at birth, this "second genome" can be manipulated in many ways.Researchers have suggested that our gut microbiome has a major role in the development of chronic conditions such as obesity, inflammatory bowel disease and asthma. Now the work has moved onto detailed analysis of the microbes in people with specific problems and measures to change the microbiome.In this major three-part series, James Gallagher investigates the key research shaping our ability not just to read our microbiome and look at predispositions, but to change it for the better. From the ability to manipulate it to stem chronic disease, to the role it plays in determining our health from birth, to its surprising influence on our brain and behaviour - should we now think of ourselves not as self-sufficient organisms, but as complex ecosystems colonized by numerous competing and health-giving microbes?Picture: Probiotic bacteria Lactobacillus, Credit: Dr Microbe/Getty ImagesProducer: Adrian Washbourne

Insects such as fruit flies provide important insights into human biology and medicine. But should we worry whether insects experience pain and suffering in scientists’ hands?Entomologist Adam Hart visits the Fly Facility at the University of Manchester where researcher Andreas Prokop describes the many insights that experiments on the fruit fly Drosophila have provided on aspects of human biology and health. Globally billions of these little flies have died in the pursuit of this knowledge.Should we give a second thought about the deaths of these creatures? Do insects have the capacity for pain and the experience of suffering? It depends which scientist you ask. Lars Chittka of Queen Mary University of London says his work on bumble bees suggests that we can’t assume they do not. Shelley Adamo of Dalhousie University in Canada is not convinced by existing arguments for insect consciousness.Photo: Robber Fly Asilidae Diptera Insect, Credit: Nechaev-kon/Getty ImagesProducer: Andrew Luck-Baker

Prof Adam Hart stirred a hornet’s nest of controversy by asking the public to kill wasps for science. He explores why scientists kill insects to save them from extinction.The work of the entomologist often involves the killing of insects in large numbers. This happens in the search for new species in the exploration of the planet’s biodiversity and in ecological research to monitor the health of wild insect populations and the impact that we are having on the environment. But the methods of insects scientists have come under criticism. Last year presenter and entomologist Adam Hart was involved in a citizen science project aimed at surveying the abundance of various species of British wasp around the country. The survey entailed members of the public setting up lethal wasp traps in their gardens and sending the dead insects to the lab running the survey. Many people took part but the study also generated negative newspaper coverage and stinging criticism on social media. How can you save insects by killing them? Next week, do insects experience pain and suffering?Picture: Broad-Bellied Chaser, Credit: BBCProducer: Andrew Luck-Baker

Two small creatures are at the heart of today’s questions, sent in to curiouscases@bbc.co.uk.The Tiniest Dinosaur "What is the tiniest dinosaur?" asks young listener Ellie Cook, aged 11.Our hunt takes us from the discovery of dinosaurs right up to the present day, which is being hailed as a 'golden age' for palaeontology. Currently, one new species of dinosaur is unearthed on average every single week. But what's the smallest dino? And what can size reveal about the life of extinct animals? Hannah Fry goes underground at the Natural History Museum in London to look through their vaults in search of the tiniest dinosaur with palaeontologist Susie Maidment. Meanwhile Adam Rutherford chats to dinosaur expert Steve Brusatte from Edinburgh University about why size really does matter, especially when it comes to fossils.The Baffled Bat "Why don't thousands of bats in a cave get confused? How do they differentiate their own location echoes from those of other bats?" This puzzling problem was sent in by Tim Beard from Hamburg in Germany. Since eco-location was first discovered, this question has perplexed biologists. Hannah turns bat detective to try and track down these elusive creatures at The Queen Elizabeth Olympic Park in East London. This is where zoologist Kate Jones from University College London is using a network of smart sensors to find, identify and track wild bats. Bat researcher and impressionist John Ratcliffe from Toronto University explains how bats use sonar to find their way around, and the clever tricks they’ve developed along the way. It's an unlikely tale involving gruesome early experiments, cunning electric fish and some surprising bat maths.(Image: Dinosaurs and a meteor falling from the sky in back background. Credit: ugurhan/Getty Images)Producer: Michelle Martin

Two astronomical questions today sent in to curiouscases@bbc.co.uk for Drs Hannah Fry and Adam Rutherford to answer.The Cosmic Speed Limit "We often read that the fastest thing in the Universe is the speed of light. Why do we have this limitation and can anything possibly be faster?" asks Ali Alshareef from Qatif from Saudia Arabia. The team grapples with Einstein's Special Theory of Relativity, with help from cosmologist Andrew Pontzen and a British train, travelling somewhat slower than the speed of light. Plus physicist and presenter Jim Al-Khalili describes how he nearly lost his boxer shorts in a daring bet concerning the speed of subatomic particles.The Cosmic Egg "How do we measure the age of the Universe?" asks Simon Whitehead. A hundred years ago this wouldn't even have been considered a valid question, because we didn't think the Universe had a beginning at all. Even Einstein thought that space was eternal and unchanging. This is the tale of how we discovered that the Universe had a beginning, and why calculating its age has been one of the greatest challenges in modern astronomy. We also uncover the mysterious dark energy that pervades the cosmos and discover why it's been putting a scientific spanner in the works. Helping to unravel today's question are physicists Andrew Pontzen, Jo Dunkley and Jim Al-Khalili.Picture: Star sun supernova galaxy gold, Credit: Eastern Lightcraft/Getty ImagesProducer: Michelle Martin

Adventures in Dreamland "Why do we dream and why do we repeat dreams?" asks Mila O'Dea, aged 9, from Panama.Hannah Fry and Adam Rutherford delve into the science of sleep. From a pioneering experiment on rapid eye movement sleep, to a brand new 'dream signature' found in the brain, they discover how scientists are investigating our hidden dreamworld. Featuring sociologist Bill Domhoff from the University of California Santa Cruz, sleep psychologist Mark Blagrove from the University of Swansea, and neurologist Francesca Siclari from the University of Lausanne.The Curious Face-Off "Are machines better than humans at identifying faces?" asks the excellently named Carl Vandal.Today’s Face Off leads our intrepid detectives to investigate why we see Jesus on toast, Hitler in houses and Kate Middleton on a jelly bean. Face perception psychologist Rob Jenkins from the University of York explains why we're so good at spotting familiar faces, like celebrities. Plus, Franziska Knolle from the University of Cambridge discusses her face recognition study involving Barack Obama and a group of highly-trained sheep. But are we outwitted by artificial intelligence when it comes to face ID? BBC technology correspondent Rory Cellan-Jones gives us the low-down on the pros and cons of current technology.Picture: Child sleeping, Credit: Quintanilla/Getty ImagesProducer: Michelle Martin

Domestic science is on the agenda today, with two culinary questions sent in by listeners to curiouscases@bbc.co.ukThe Curious Cake-Off Can chemistry help us bake the perfect cake? Listener Helena McGinty aged 69 from Malaga in Spain asks, "'I have always used my mother's sponge cake recipe. But is there a noticeable difference in the outcome if you vary some of the ingredients, or the method?"Hannah and Adam go head to head in a competition to create the perfect cake using the power of science. They are aided by materials scientist Mark Miodownik, from University College London, with tips on how to combine the ideal ingredients and trusted techniques to construct a structurally sound sponge. Food critic Jay Rayner is on hand to judge the results. But who will emerge victorious in this messy baking battle?The Atomic Blade "What makes things sharp? Why are thinner knives sharper? What happens on the molecular level when you cut something?" All these questions came from Joshua Schwartz in New York City.The ability to create sharp tools allowed us to fashion clothing, make shelters and hunt for food, all essential for the development of human civilisation. And, more importantly today they allow us to prepare dinner. So what makes kitchen knives sharp? We hear from IBM scientist Chris Lutz, who has used one of the sharpest blades in the world to slice up individual atoms. Plus palaeoarchaeologist Becky Wragg Sykes reveals the sharpest natural object in the world, a volcanic glass used by the Aztecs called ‘obsidian’.Picture: Colourful Cupcakes, Credit: RuthBlack/Getty ImagesProducer: Michelle Martin

Two very annoying cases today sent in by listeners to curiouscases@bbc.co.uk to our scientific sleuths, mathematician Dr Hannah Fry and geneticist Dr Adam Rutherford.The Sticky Song Why do songs get stuck in our heads? And what makes some tunes stickier than others? Drs Rutherford and Fry investigate 'earworms', those musical refrains that infect our brains for days. Every morning BBC 6Music DJ Shaun Keaveny asks his listeners for their earworms, and Hannah finds out which tunes keep coming back. Adam asks Dr Lauren Stewart, from Goldsmiths University, to reveal the musical features that make some songs catchier than others. And they find out why, in times of crisis, an earworm may just save your life.The Shocking Surprise Jose Chavez Mendez from Guatemala asks, "Some years ago, in the dry season, I used to be very susceptible to static electricity. I want to know - why do static shocks happen?"The team uncover some slightly unethical science experiments on static electricity from the 1700s. Hannah Fry uses a Leyden Jar to demonstrate how static electricity works with help from her glamorous assistant, Adam Rutherford. Spoiler Alert: it doesn't end well for Adam. They discover what makes some people more susceptible to static shocks, and how bees and spiders have harnessed the awesome power of electricity.Featuring electromagnetism scientist Rhys Phillips and physicist Helen Czerski, author of 'Storm in a Teacup: The Physics of Everyday Life'.Picture: Human Ear, Credit: Techin24/Getty ImagesProducer: Michelle Martin

Humans have become the most successful species on earth because of our ability to cooperate. Often we help strangers when there is no obvious benefit to us as individuals. But today in the age when social media and the internet could be seen as a way of bringing people together more than ever, the opposite is happening. In this two-part series for Discovery science writer Gaia Vince meets the psychologists, evolutionary biologists and neuroscientists who are studying our built in human behaviour in groups and asks how their discoveries can guide projects to increase cooperation.(Photo: Support button on keyboard, Credit: Abdoudz/Getty Images)