Discovery

In March astronomers in the BICEP2 collaboration announced they had found gravitational waves from the Big Bang. But now the evidence is being questioned by other scientists. Dr Lucie Green reports on the debate and asks if scientists can ever know what happened billions of years ago when the universe was formed.Image copyright: Steffen Richter, Harvard University

On 6th August, the space probe Rosetta ends its 10 year journey and arrives at Comet 67P/Churyumov-Gerasimenko. If all goes well, Rosetta will be the first spacecraft to go into orbit around a comet. The European Space Agency probe will then accompany the comet until December 2015, studying the 4 kilometre-wide lump of ice and rock dust at a level of detail far surpassing any previous comet flyby.In the words of Rosetta scientist Joel Parker, “Previous comet missions have been one-night stands, Rosetta will be there for a long term relationship.” Rosetta will stay with 67P as it heads towards and around the other side of the Sun. Rosetta will be watching everything at close quarters as the comet heats up and produces the classic gas and dust comet tail.In the final weeks of approach, the Rosetta team have realised this is going to be an even more interesting mission than they had supposed. In the middle of July, the probe’s camera revealed the bizzare shape of the comet’s nucleus. It appears to be formed of two objects joined together. Some have described it as having the shape of a toy duck. In November, Rosetta will send a small robot lander, Philae, down onto the comet’s surface – another hugely ambitious feat, given the feeble gravitational pull of the comet and its complex shape. Philae could bounce off into the void if its trajectory is not quite true and its on-board harpoons fail to secure it to the comet’s icy surface. Discovery looks ahead to the mission’s key moments and big science questions with planetary scientists and members of the Rosetta science team: Professor Ian Wright - principal investigator (PI) for the lander’s Ptolemy instrument, Professor Monica Grady - planetary scientist at the Open University, UK. Matt Taylor, project scientist on Rosetta Dr Joel Parker - deputy PI for Rosetta’s Alice spectrometer Dr Holger Sierks - principal investigator for Rosetta’s Osiris camera Dr Stephan Ulamec - project scientist for the lander Philae (German Space Agency) The big questions for Rosetta include: did comets bring water and the essential ingredients for life to the early Earth?Presented and produced by Andrew Luck-Baker Image Credit: Rosetta and Philae at Comet, European Space Agency

Professor Sir Michael Rutter has been described as the most illustrious and influential psychiatric scientist of his generation. His international reputation has been achieved despite the fact that as a young doctor, he had no intention of becoming a researcher, nor interest in becoming a child psychiatrist. In fact he became a world leader as both. His career has spanned more than five decades and is marked by a remarkable body of high-impact research and landmark studies. The theme running through all his work has been child development, on the subtle interplay between nature and nurture and on the factors that make the difference between a child flourishing, or floundering. Evacuated during World War Two, to a Quaker family in the USA, Mike Rutter tells Jim al-Khalili about the impact this move, aged seven, had on him. He describes the inspirational teachers who persuaded him that research and clinical work as a child and adolescent psychiatrist, was for him, and he admits that an early mentor insisted he mustn't receive any formal training in child psychiatry, something he hasn't received to this day! He was awarded this country's first ever professorship in child psychiatry in 1973 and he's credited with founding the field of developmental psychopathology. This involves the study, over time, of normal and abnormal child development. He's currently Professor of Developmental Psychopathology at King's College, London and still a practicing child psychiatrist. An early breakthrough was his discovery that autism, or inifantile psychosis as it was then known, had a genetic basis, something barely suspected at the time. Beautifully designed studies of populations over time followed, many of them landmark studies still cited today. They established the framework for studying and investigating mental illness in the community. The Isle of Wight Studies (1964-74) surveyed the mental health of children living on the island and for the first time in such research, children themselves were directly interviewed and questioned. Before this, Mike Rutter tells Jim, the assumption had been that what children thought and said didn't really matter. In the 1970s, the Fifteen Thousand Hours study, delivered ground-breaking evidence about the combination of factors that affected the performance and behaviour of children in inner city secondary schools. Findings from this study were included by both the Labour and Conservative parties in their 1979 election manifestos. "Maternal Deprivation Reassessed" was Mike Rutter's challenge to John Bowlby's hugely influential theory of maternal attachment. It was described as "a classic in the field of childcare" and it transformed the debate about the relationships that help babies to flourish. His fascination with the underlying reasons why and how children vary in their ability to weather and cope with adversity, led to the growth of resilience science. For more than 40 years Mike Rutter, "the intellectual father", has led this field of study. His name is particularly associated with "natural experiments" and one of the best known is the English Romanian Adoptees study that he set up in the early 1990s and still runs today. The children being followed are those rescued from the orphanages of Nicolai Ceausescu and adopted by families in this country. Because of the appalling conditions many of these babies and toddlers experienced in Romanian institutions, Professor Rutter understood that tracking and studying them as they grew up in loving homes here, would provide important insights into how early deprivation affects childrens' development. Producer: Fiona HillImage: Professor Sir Michael Rutter, BBC Copyright

At the start of 2014 meteorologists warned of a possible El Nino event this year. The portents were persuasive – a warming of the central Pacific much like that which preceded the powerful El Nino event of 1997. But since then the Pacific climate system seems to have stalled. What’s going on? What are the prospects for an El Nino to develop later this year? What impacts might it have? Roland Pease delves below the Pacific surface to find out what drives El Nino cycles, the most powerful single climate fluctuation on the planet, and asks the experts why it is so hard to forecast. “The year started with a bang,” one expert tells Discovery - will it end with a whimper?(Photo: Burned swamp forest in Kalimantan. Credit: Florian Siegert, RSS GmbH)

Adam Hart looks at how new developments in understanding insect behaviour, plant cell growth and sub cellular organisation are influencing research into developing robot swarms. Biological systems have evolved elegant ways for large numbers of autonomous agents to govern themselves. Staggering colonies built by ants and termites emerge from a decentralized, self-governing system: swarm intelligence. Now, taking inspiration from termites, marine animals and even plants, European researchers are developing autonomous robot swarms, setting them increasingly difficult challenges, such as navigating a maze, searching for an object or surveying an area. At the same time, an American team has announced that its group of robots can autonomously build towers, castles and even a pyramid. Adam Hart reports on the latest developments in controlling groups of robots, and asks why models taken from the behaviour of social insects such as bees, ants and termites may be far more complex than previously thought. He also delves deep into the cells of plants looking at how the physical and chemical triggers for plant growth might be useful in robot design.Image: Presenter Adam Hart with ‘Swarmbots’ at Britain’s Surrey University, BBC Copyright

General anaesthetics which act to cause reversible loss of consciousness have been used clinically for over 150 years. Yet scientists are only now really understanding how these drugs act on the brain and the body to stop us feeling pain. Linda Geddes reports on the latest research using molecular techniques and brain scanners. Linda visits the Anaesthesia Heritage Centre where William Harrop-Griffiths, president of the Association of Anaesthetists of Great Britain and Ireland, tells her about the discovery of agents that knock us out. And, as an operation takes place in the Royal United Hospital in Bath, professor Tim Cook explains the role of the anaesthetist. Linda also talks to professor Nick Franks of Imperial College, London, about his research into how anaesthetics work at the level of the cell. Irene Tracey, professor of Anaesthetic Science at Oxford University, discusses how her fMRI scans of people as they slowly undergo anaesthesia have revealed how the brain switches off. Professor Steven Laureys, head of the Coma Science Group at Liege Universiy in Belgium, explains how understanding anaesthesia can help coma patients and what it tells us about the difficult question of human consciousness.

Janet Hemingway, the youngest woman to ever to become a full professor in the UK, talks about her career at the frontline of the war on malaria. Whilst many researchers look for vaccines and treatments to this global killer, Janet's approach, as a trained entomologist, has been to fight the mosquito - the vector - which transmits the malaria parasite.Image: Janet Hemingway, BBC Copyright

Geoff Watts investigates the latest thinking about our brain power in old age. He meets researchers who argue that society has overly negative views of the mental abilities of the elderly - a dismal and fatalistic outlook which is not backed up by recent discoveries and theories. Geoff talks to professor Lorraine Tyler who leads a large study in Cambridge (CamCAN) which is comparing cognition and brain structure and function in 700 people aged between 18 and 88 years old. He also meets scientists and participants involved in a unique study of cognition and ageing at the University of Edinburgh. It has traced hundreds of people who were given a nationwide intelligence test as children in 1932 and 1947. Since the year 2000, the study has been retesting their intelligence and mental agility in their 70s to 90s. The Lothian Birth Cohort study is revealing what we all might do in life to keep our minds fast and sharp well into old age. One new and controversial idea holds that cognitive decline is in fact a myth. A team in Germany, led by Michael Ramscar, argues that older people perform less well in intelligence and memory tests because they know so much more than younger subjects and not because their brains are deteriorating. Simply put, their larger stores of accumulated knowledge slow their performance. Their brains take longer to retrieve the answers from their richer memory stores. Producer: Andrew Luck-Baker

Jack Stewart meets the engineers who are building vehicles that drive themselves. He has a ride in Google's driverless car, which has no steering wheel and no pedals. Google's Chris Urmson explains the company's approach to autonomous vehicles. Jack visits Stanford University's driverless car project where professor Chris Gerdes shows him Shelley, an automated Audi that races around a track at speed as well as a human driver. Chris is collaborating with a philosopher to explore some of the difficult questions around autonomous vehicles, such as who is liable if there's an accident. Is it the human or the car? And ,Jack meets Josh Swirtes whose company, Peloton, is linking trucks together with the idea that they should have fewer accidents. (Photo: Jack Stewart in Stanford's University X1)

Most traffic accidents are caused by human error. Engineers are designing vehicles with built in sensors that send messages to other cars, trucks, bikes and even pedestrians, to prevent collisions happening. The idea is to make the vehicles react to whatever's going on faster than the human drivers. Jack Stewart drives around the university town of Ann Arbor, in Michigan, in some of the many vehicles that are fitted with experimental devices in the world's largest connected vehicles project. He finds out how the system works from researchers at UMTRI, the University of Michigan's Transportation Research Institute, including the director, professor Peter Sweatman and human factors expert Dr Jim Sayer, Kirk Steudle, Director, Michigan Department of Transportation and a resident who has had her car fitted with an experimental device. (Photo: Right hand wing mirror, Nevada, USA, BBC copyright)

ITER is the most complex experiment ever attempted on this planet. Its aim, to demonstrate that nuclear fusion, the power of the Sun, can give us pollution free energy that we can use for millions of years. But at the moment, it's still largely a vast building site in the Haut Provence of southern France, with little prospect of any nuclear reactions there for another decade. A recent management report made damning criticisms of the way ITER is run, of the relations between the central organisations, and the seven partners (USA, Russia, Japan, China, South Korea, India and Europe) contributing to the project. Roland Pease has been to Cadarache to see how work is progressing, and to hear of the hopes of the scientists who have dedicated their working lives to the dream. (Photo: The empty magnet-winding hall at ITER, BBC copyright)

Dr Tiffany Jenkins asks what our brains can tell us about art. Can there ever be a recipe for beauty? Or are the great works beyond the powers of neuroscience? She talks to Professor Semir Zeki of University College London, the first person to coin the term, neuroaesthetics, about what happens in the brain when people in a scanner see paintings or hear music. Professor Gabi Starr at New York University tells Tiffany Jenkins why she thinks there are parts of the brain that light up when we like an art work. Tiffany visits Christie's auction house to explore whether the best art always commands the best prices.She also talks to Martin Kemp, Emeritus Professor of Art History at Oxford University, about our different responses to authentic paintings and to fakes. And Tiffany discusses with art critic JJ Charlesworth why neuroscience is having an influence in some areas of art appreciation.Picture: The reflection of trees in water, Credit: Getty

Alf Adams FRS, physicist at the University of Surrey, had an idea on a beach in the mid-eighties that made the modern internet, CD and DVD players, and even bar-code readers possible. You probably have half a dozen 'strained-layer quantum well lasers' in your home.Image credit: Alf Adams, BBC Copyright

Mark Miodownik's chronic interest in materials began in rather unhappy circumstances. He was stabbed in the back, with a razor, on his way to school. When he saw the tiny piece of steel that had caused him so much harm, he became obsessed with how it could it be so sharp and so strong. And he's been materials-mad ever since. Working at a nuclear weapons laboratory in the US, he enjoyed huge budgets and the freedom to make the most amazing materials. But he gave that up to work with artists and designers because he believes that if you ignore the sensual aspects of materials, you end up with materials that people don't want. For Mark, making is as important as reading and writing. It's an expression of who we are, like music or literature, and 'everyone should be doing it'. To this end, he wants our public libraries to be converted into public workshops, with laser cutters and 3 D printers in place of books.Image: Mark Miodownik, BBC Copyright

Forensic anthropologist professor Sue Black began her career with a Saturday job working in a butcher's shop. At the time she didn't realise that this would be the start of a lifelong fascination with anatomy. Her job has taken her to some extreme and challenging locations to identify human bodies, such as Kosovo, where she uncovered evidence used in the UN's War Crimes Tribunal in The Hague. Back home, Sue has been integral in solving many high-profile criminal cases, including cracking Scotland's biggest paedophile ring in 2009. In The Life Scientific, Jim al-Khalili asks how she deals with the emotional pressures of the job, and why she is so fascinated by the inner workings of the human body. In her spare time, Sue Black also advises crime fiction authors like Val McDermid, providing inspiration for new plotlines and characters. In return, Val and a group of writers have offered to help with Sue's latest challenge - fundraising for a mortuary. This facility will use new techniques to embalm bodies and promises to revolutionise the way surgeons are trained. (Photo: Sue Black, BBC copyright)

Whatever happened to biofuels? They were seen as the replacement for fossil fuels until it was realised they were being grown on land that should have been used for food crops. But now there is serious research into new ways of producing biofuels, from waste materials, from algae and from bacteria. Gaia Vince takes to the water of Strangford Lough in Northern Ireland where Professor Matthew Dring and Dr Karen Mooney from Queens University, Belfast, are experimenting in growing algae that could be turned into fuel. She visits Professor Alison Smith's algae lab at Cambridge University. Graham Ellis from Solazyme in California explains how his company has already made fuel from algae that has been sold at the pumps and powered a plane, in a mixture with conventional fuel. And Professor Nick Turner at Manchester University and Professor John Love at Exeter University talk about how they are manipulating bacteria to make diesel.

Biofuels were hailed as the environmental solution to fossil fuels not that long ago. Made from living crops they take up carbon dioxide as they grow. So burning them shouldn’t disturb the balance of warming gases in the atmosphere. But for the last few years the publicity about biofuels has been mainly negative. And for good reason – biofuels are made from crops such as oil palm - grown in place of food crops or even rainforests. In some cases using these crops actually produces more CO2 than burning fossil fuels. However research is being done into new kinds of biofuels that aren’t in competition with food crops. Gaia Vince travels to Bavaria in Germany to meet Dr Markus Rarbach, head of biofuels at Clariant. This company has set up a demonstration plant that produces ethanol from sugars in the waste products of wheat grown nearby. Also on the programme is professor Gregory Tucker from Nottingham University who talks about research into new ways of getting sugars out of the inedible parts of crops; agricultural economist, Dr Paul Wilson, discusses what farmers think about making biofuels out of their straw; and Dr Angela Karp at Rothamsted Research, who is growing new willow varieties, which could be made into biofuels. Image Credit: Clariant

An extended interview with the Nobel prize laureate. Peter Higgs tells Jim Al-Khalili that he failed to realise the full significance of the Higgs boson and to link it to the much celebrated Standard Model of Physics. He puts the oversight down to a string of missed opportunities, including one night at a physics summer camp when he chose to go to bed early. Working alone in Edinburgh in the 1960s, Peter Higgs says he was considered "a bit of a crank... No-one wanted to work with me". In 1964, he predicted the possible existence of a new kind of boson but, at the time, there was little interest. Three years later, the Higgs mechanism was shown to be central to the new Standard Model of Physics, which brings together three of the four fundamental forces of nature and has dominated physics ever since. Higgs met one of the key architects of the Standard Model several times, but they failed to realise they were working on the same thing. The 1970s were an exciting time for particle physics but Higgs says he lacked technical competency. He adds that work pressure contributed to the breakdown of his marriage. Four decades and several billion pounds on, scientists at the Large Hadron Collider at CERN confirmed that the Higgs boson had indeed been found and Peter Higgs shot to fame. This ephemeral speck of elusive energy is now so well-known it's featured in car adverts and countless jokes. There's even song by Nick Cave called the Higgs Boson Blues. But Higgs has always called it the 'scalar boson' and remains embarrassed that it is named after only him. He remains surprised that another British physicist, Tom Kibble from Imperial College, London didn't share the 2013 Nobel Prize for Physics along with him and Belgian physicist, Francois Englert. These days, he's constantly stopped in the street and asked for autographs and photographs which, he says, is "nice but a bit of a nuisance". Producer: Anna Buckley Image Credit: BBC

Jim al-Khalili talks to psychiatrist Vikram Patel about the global campaign he is leading to tackle mental health. He reflects on his early career working in Zimbabwe, when he doubted any western diagnosis or treatments for peoples' distress would be of much use. However, his subsequent research made him question this and come to the realisation that some conditions, like depression and psychosis, could be tackled universally. Now based in India, Vikram's research guides the public health approach he is taking. Yet critics question the application of Western categories for diagnosis and treatment to other parts of the world. (Photo: Vikram Patel)

Fatal shark attacks on humans have been on the increase in Australia. For Discovery, marine biologist Dr Helen Scales finds out how scientists are exploring new, humane ways to reduce this number. At the start of this year, the state government of Western Australia decided to undertake the culling of sharks longer than three metres, after what they called an “unprecedented number of attacks”. In February, thousands of Australians protested against the cull, with conservationists claiming that it will make no difference to the number of attacks. An outspoken critic of the strategy is Rodney Fox, who was almost killed by a Great White shark when he was a young man but who subsequently made a 50-year-long career filming sharks, shark tourism and shark conservation. Rodney talks to Helen about the day he was attacked and his thoughts about the Western Australian cull. Rodney argues that another approach is needed.On a mission to reduce shark attacks, a team has been formed at the Ocean Institute, University of Western Australia (UWA). Their task is to think like a shark to understand how a shark’s brain perceives and reacts to light, sound and vibrations, and how the shark’s finely tuned senses might be manipulated in the hunt for more effective, humanitarian shark repellents. Research revealed that Great Whites have large chunks of their brain dedicated to vision. So UWA are developing and testing a shark-proof wetsuit that mimics the appearance of poisonous, striped sea snakes. Other solutions under study include bubble curtains and the use of devices which generate electric fields around swimmers.Helen also questions whether sharks deserve their reputation as the most fearsome predators of the sea. Have they been misunderstood and mythologised by popular culture through films such as Jaws and Deep Blue Sea. Proving that even the most predatory of sharks are not automatic man-eaters, Helen herself goes diving with dozens of huge bull sharks (one of the most aggressive species) and comes to the surface unscathed. These three metre long monsters have been trained to be hand-fed by locals while tourists watch close by. Helen also talks to veteran shark researcher Eugenie Clark about the predators’ learning abilities and intelligence. Dr Clark was able to train sharks to learn to press the correct buttons with their snouts to get a food treat. She even presented the Crown Prince of Japan with a baby nurse shark who never made a mistake.(Photo: Courtesy of Helen Scales)

Is free will unique to humans or a biological trait that evolved over time and across species? Whilst the existence and nature of free will has been hotly debated by philosophers through the centuries, the basic idea that we determine our own destiny is fundamental to human experience. We can even decide to act in ways which may threaten our very existence. Biology underpins how we behave but it is the human mind that decides to act. Recently, however, this idea has come under attack from neuroscience research which has shown our sense of freedom to be something of an illusion. MRI scans suggest our brains make decisions several seconds before we are consciously aware of them. We have an ability to react to new situations, to be unpredictable and even illogical, to the point of self-destruction. But look closely and these qualities can also be found across the animal kingdom. From bonobos to bacteria, organisms are making what appear to be independent decisions in surprising ways. As part of the Freedom 2014 season, entomologist Adam Hart explores the biology of freedom, meeting researchers working with apes, birds, insects and even single-celled microbes, who are redefining the way we think about free will and its origins.(Image Credit: Joshua Hart)

If you believe the headlines fructose is 'addictive as cocaine', a 'toxic additive' or a 'metabolic danger'. So how has a simple sugar in fruit and honey got such a bad name and is there any evidence behind the accusations that it has caused the obesity epidemic? Meanwhile, a new health claim approved by the European Food Safety Authority for foods or drinks substituting fructose for other sugars, comes into force. Dr Mark Porter talks to leading world experts to sift through the evidence in Fructose: The Bitter Sweet Sugar.Picture: Ingredients list on a drinks bottle, Credit: Associated Press

Audiologists are concerned there may be a rising tide of 'hidden hearing loss' among young people. As electronic prices have fallen, sound systems have become cheaper and more powerful. At the same time, live music events and personal music players are more popular than ever, resulting in an increase in noise-related hearing damage. Aged 32, science writer Frank Swain is losing his hearing. In this programme, he asks what the future holds for people like him, part of a tech-savvy generation who want to hack their hearing aids to tune in to invisible data in the world around them. Could these designers and hackers create the next super sense? (Photo: Graphic design shows an ear with computer sound waves. Credit: Getty Images)Credits: Sound files of tinnitus kindly provided by Action on Hearing Loss. Free Helpline: 0808 808 0123.Sonified data produced by Semiconductor, with audio courtesy of CARISMA, operated by the University of Alberta, funded by the Canadian Space Agency. Special thanks to Andy Kale. Colour music created by cyborg artist Neil Harbisson.

Gardening grandmother Ruth Brooks, also known as 'the snail lady', was chosen as the BBC's Amateur Scientist of the Year in 2010. She noticed that despite repeatedly throwing her snails over the garden fence, her gastropods would return home to decimate her petunias. From her Radio 4 experiments, designed by mentor Dr Dave Hodgson, from the University of Exeter, they showed that snails do have a homing instinct, returning from distances of over 10 metres. In this documentary, Ruth sets out to investigate how different animals navigate, from smell maps for cats to astronomy for dung beetles. She travels to Portsmouth to meet some speedy pigeons and visits an MRI laboratory where neuroscientists are hunting for the source of their mysterious magnetic sense. But do we humans have a homing instinct, and can we improve our sense of direction?

In part four of Saving the Oceans, Joel finds out how knowledge of the seas from Australia’s Aboriginal communities can feed into modern ocean science. And at Seasim - the world’s largest marine research laboratory - he looks at the ways human fertilisation treatments are being applied to help conserve coral. This includes techniques from human sperm banks being applied to coral. He also speaks to the scientists unlocking coral genetics in an attempt to help them survive rising sea temperatures.(Image: Inside the SEASIM facility at the Australian Institute of Marine science a Coral Sperm Bank is being developed)

We look at the impact of climate change, overfishing and pollution on marine eco-systems and examine the scientific solutions to some of those issues. Presented by Joel Werner from the Australian broadcaster ABC Radio National, the series focuses on the improvements both for marine life and the people who depend on oceans for their livelihoods.In the third programme Joel looks at how data analysis has helped reduce deaths of seabirds caught up in commercial fishing operations. He hears how the same operations may have also had an evolutionary impact on the birds. He looks at the effects of a plague of coral eating starfish on Australia’s Great Barrier Reef. And he hears how undersea volcanic activity near Papua New Guinea is providing clues about the future direction of ocean climate change.

The second episode in our four-part series Saving the Ocean in which we look at the impact of climate change, overfishing and pollution on ocean environments, and examine the scientific solutions to some of those issues. Presented by Joel Werner from the Australian broadcaster ABC Radio National, the series focuses on the improvements both for marine life and the people who depend on oceans for their livelihoods.In this second programme Joel looks at plans to help conserve sharks in the waters around remote Pacific islands. A shark fin export trade to Asia has provided a lucrative but ultimately unsustainable income for the islanders. And he visits New Zealand, where a high-tech solution has been designed to help sustainably harvest a different valuable export commodity - marine snails. A high demand from Asia for this delicacy has endangered the snails. Joel hears how digital technology is being used to track them to ensure there are enough left to breed. He also sees what tracking technology is revealing about how seabirds are affected by commercial fishing practices.(Image: Paua fishermen examine their catch. BBC copyright)

Saving the Ocean looks at the impact of climate change, overfishing and pollution - and examines the scientific solutions to some of those issues. In the first programme Joel Werner visits Kiribati – an isolated Pacific island group threatened by rising sea levels. They are also facing a range of more immediate problems - a high human population and a shortage of land puts pressure on natural resources. Joel meets the scientists working to keep the population afloat on these tiny coral atolls. He finds out about how this island group is threatened by sea level rise and changing weather patterns - and how in some cases, poor sea defence management is making the erosion of the islands worse.(Image: Low tide reveals the detritus of 50,000 people on South Tarawa, Kiribati, BBC copyright)

Today, 3.5 billion people are alive because of a single chemical process. The Haber-Bosch process takes nitrogen from the air and makes ammonia, from which synthetic fertilizers allow farmers to feed our massive population. Ammonia is a source of highly reactive nitrogen, suitable not just for fertilizer, but also as an ingredient in bomb making and thousands of other applications. We make around 100 million tonnes of ammonia annually - and spread most of it on our fields. But this is a very inefficient way to use what amounts to 1-2% of the planet's energy needs. Only around 20% of fertilizer made ends up in our food. Professor Andrea Sella explores some of the alternative ways we might make fertilizer. Vegetables such as peas and beans, allow certain cells in their roots to become infected by a specific type of bacteria. In return, these bacteria provide them with their own fertilizer. Could we infect the plants we want to grow for food – such as cereals – in a similar way to cut down the climatic and environmental impact of Haber-Bosch?

Are you a lark or an owl? Are you at your best in the morning or the evening? Linda Geddes meets the scientists who are exploring the differences between larks and owls. At the University of Surrey's Sleep Research Centre she talks to its director, professor Derk-Jan Dijk, and finds out her own chronotype by filling in a questionnaire. Linda discovers why we have circadian rhythms and why they do not all run at the same rate. Dr Louis Ptacek from the University of California, San Francisco, explains his investigation of the genes of families whose members get up very early in the morning and of those who get up very late. She finds out why our sleep patterns change as we age – teenagers really are not good at getting up in the morning. Professor Mary Carskadon from Brown University explains that although some schools have experimented with a later start there is no plan to put this into universal practice. Linda talks to Professor Til Roenneberg from Ludwig-Maximilians-University Munich about his concept of social jetlag. And she hears about research trying to reduce the exhaustion often suffered by shift workers. Dr Steve Lockley of Harvard University tells her about using blue light to improve the wellbeing of people with medical conditions.

Geoengineering is a controversial approach to dealing with climate change. Gaia Vince explores the process of putting chemicals in the stratosphere to stop solar energy reaching the earth. When volcanoes erupt they put sulphur in the stratosphere. The particles reflect solar rays back into space and the planet cools down. Scientists are suggesting that it could be possible to put sulphur into the stratosphere using specialised aircraft or a very long pipe. But if this was implemented there could be impacts on rainfall and the ozone layer. Another idea is to spray seawater to whiten clouds that would reflect more energy away from the earth. Gaia Vince talks to the researchers who are considering solar radiation management. She also hears from social scientists who are finding out what the public think about the idea and who are asking who should make decisions about implementing this way of cooling the planet.(Photo: The ocean with the sun rising in the horizon)

The Australasian Antarctic Expedition has been retracing the steps of the first expedition to East Antarctica, a century ago. Its leader was Douglas Mawson, one of the great figures of the heroic age of exploration of the frozen continent. In the last of the programmes from the Antarctic, Andrew Luck-Baker reports on the 10 days the scientists, tourists and crew of the ship, the Academik Shokalskiy, spent locked in the ice and their eventual release via helicopters from a Chinese ice breaker to an Australian vessel.

Alok Jha and Andrew Luck-Baker continue to follow the scientists on the ongoing Australasian Antarctic Expedition 2013. They go out on fieldwork trips with the researchers studying how the wildlife that lives in this inhospitable environment is responding to climate change. Zoologist Tracy Rogers searches for leopard seals with underwater microphones. From a safe distance she takes a small sample from a Weddell seal to find out what it’s been eating. Ornithologist Kerry-Jayne Wilson discovers that an iconic breeding colony of Adelie penguins at Cape Denison, the rocky area where Douglas Mawson built his expedition hut, has depleted numbers as the fast ice has grown. Producer: Andrew Luck-BakerImage: Ice-blocked bow of the Shokalskiy and expedition doctor Andrew Peacock

Alok Jha and Andrew Luck-Baker continue to follow the scientists on the ongoing Australasian Antarctic Expedition 2013. Ice, the oceans and climate change are the themes this week as one of the expedition scientists makes a troubling finding. Moored in Commonwealth Bay in East Antarctic, the expedition’s oceanographer Erik van Sibble discovers a stunning difference in the nature of the water beneath the sea ice. Although it is a preliminary finding, the consequences for the motions of the world’s oceans and climate change could be dramatic. With thanks to AAE volunteer scientist Terry Gostlow for sound recording assistance.

Join the scientists of the Australasian Antarctic Expedition 2013, as they go about their experiments and seek adventure at the windiest place on earth.This location was named the Land of Blizzard by Douglas Mawson, the Antarctic pioneer who was the first to explore this remote and desolate place 100 years ago.Between 1911 and 1914, Douglas Mawson explored a fiercely harsh part of Antarctica while the more celebrated Scott and Amundsen raced to the South Pole, elsewhere on the frozen continent. Mawson’s expedition was dedicated to scientific study in the early Heroic Age of Antarctic Exploration but his journey was fraught with horror and danger. The 2013 Australasian Antarctic Expedition aims to repeat many of Mawson’s investigations around Commonwealth Bay and Cape Denison in East Antarctica where the original team set up their base. This remote area hasn’t been studied systematically for 100 years, so the expedition will reveal any changes that have taken place as a result of climate change.

Quentin Cooper takes a look at the new materials that can mend themselves. Researchers are currently developing bacteria in concrete which, once awakened, excrete lime to fill any cracks. In South America you can choose a car paint that heals its own scratches. And there are even gold atoms which can migrate to mend tiny breaks in jet turbine blades.Engineers normally design things so the likelihood of breaking is minimised. But by embracing the inevitability of breakage, a new class of materials which can mend cracks and fissures before you can see them may extend the lives of our cars, engines, buildings and aeroplanes far beyond current capability.(Image: Presenter, Quentin Cooper, BBC Copyright)

We like to think that we are in control of our lives, of what we do, think and feel. But, as Geoff Watts discovers, scientists are now revealing that this is just an illusion. A simple magic trick reveals just how limited our conscious awareness of the world is, and how easy it is to fool us. So if our conscious brain can cope with so little, what is responsible for the rest? Science is starting to reveal the crucial role of a silent partner inside our heads, that we are completely unaware of – our unconscious. In this programme, Geoff enlists the help of, not just brain scientists but, a conjuror and a musician to reveal the pivotal role the unconscious plays in pretty much everything we do, think and feel. This new-found knowledge is enabling scientists to harness its powers for both medical and military benefit.

The human gut has around 100 trillion bacterial cells from up to 1,000 different species. Every person's microbiota (the body's bacterial make-up) is different as a result of the effects of diet and lifestyle, and the childhood source of bacteria. What is it about the microbes in our guts that can have such an impact on our lives? Scientists are learning more and more about the importance of these bacteria, as well as the viruses, fungi and other microbes that live in our gastrointestinal tracts. Without them, our digestion, immune system and overall health would be compromised. Adam Hart talks to researchers who are discovering how important a balanced and robust gut microflora is for our health. And he asks how this can be maintained and what happens when things go wrong.(Image: Gut Microbiota Copyright: Getty Images)

Journalist and numbers obsessive Alex Bellos travels around India to explore the fundamental numerical gifts which early Indian mathematicians gave to the world and asks whether the great religions of ancient India - Hinduism, Buddhism and Jainism - had any part in their origins. The number system which the world uses today originated in India in the early centuries of the first millennium AD. It is usually called the Arabic numeral system, but in the Middle East the scheme employing the symbols 0 to 9 is correctly referred to as the Indian system. The designation of zero as a number in its own right by South Asian thinkers was arguably the greatest conceptual leap in the history of mathematics. During his numerical odyssey, Alex visits a temple in Gwalior, containing the earliest zero in India with a known date. He is also granted an audience with one of Hinduism's most revered gurus, who is also an author of books on numbers. His Holiness, the Shankaracharya of Puri tells Alex that the study of mathematics is a path to Nirvana. In conversation with India's most eminent mathematician, Professor SG Dani in Mumbai, Alex hears how early Indian philosophers toyed with numbers far more than the Greeks. Buddhists, for example, mused on a number with 53 zeros and the Jains contemplated various varieties of infinity - something that modern mathematicians do 2000 years later. Alex also dips into the current controvesy surrounding so-called Vedic mathematics. This is a collection of speed arithmetic tricks which a great guru of the early 20th Century claimed to have discovered in the Vedas, Hinduism's most sacred scriptures.(Image: One of the special zeros in its use in '270'. Credit: Andrew Luck Baker)

Australian geneticist Jenny Graves discusses her life pursuing sex genes in her country's weird but wonderful fauna, the end of men and singing to her students in lectures.(Image: Jenny Graves, BBC copyright)

Life on earth has gone through a series of mass extinctions. Mike Benton talks about his fascination with ancient life on the planet and his work on the Bristol Dinosaur Project.Image: Mike Benton BBC Copyright

Joanna Haigh, Professor of Atmospheric Physics at Imperial College, London, studies the influence of the sun on the Earth's climate using data collected by satellites. She talks to Jim al-Khalili about how she got started on her career in climate physics: she can trace her interest in it back to her childhood when she built herself a home weather station. Jo Haigh explains why we need to know how the sun affects the climate: it's so scientists can work out what contribution to warming is the result of greenhouse gases that humans produce, and what is down to changes in the energy coming from the sun. She has sat on the Intergovernmental Panel on Climate Change and discusses with Jim how it delivers its reports. And as a prominent scientist who speaks out about the dangers of increasing man made greenhouse gases in the atmosphere, she explains how she responds to climate change deniers. Image: Joanna Haigh Credit: BBC

Russell Foster, professor of circadian neuroscience at Oxford University, is obsessed with biological clocks. He talks to Jim al-Khalili about how light controls our wellbeing from jet lag to serious mental health problems. Professor Foster explains how he moved from being a poor student at school to the scientist who discovered a new way in which animals detect light. Image: Russell Foster Copyright: BBC

Adam Hart investigates yet another threat to the ash trees of Europe. In the last programme he found out about the latest research developments to save ash trees from ash dieback, a disease that has already devastated trees across Europe, but now it seems that another threat could be on its way from Russia – the emerald ash borer. This beetle already targets ash trees in the USA and kills 99% of the trees it infests. But, what is it, how great is the threat and is there any way to stopping it spreading to Europe?Image: Emerald Ash Borer Traces Credit: Cornelia Schaible

Professor Adam Hart looks at the disease that has devastated ash trees in Europe – ash dieback. Over the last 20 years the fungus that causes ash dieback has been spreading westwards across the continent and last year it was found in the UK for the first time. At the moment there is no cure for the disease and only a tiny fraction of trees seem to be able to survive it. In this programme, he investigates the very latest scientific research into this deadly disease and asks if it will be enough to save this important species.(Image: Professor Adam Hart in Trolleholm seed orchard in Sweden where ash dieback has infected many of the trees. Credit: BBC)

Fracking for gas is highly controversial in the US and the UK as it has been accused of contaminating water courses and causing earthquakes. Yet it provides a cheap source of energy. Beneath England there are thought to be considerable amounts of shale gas and the UK government is considering whether to allow fracking in these areas. Already there is opposition from residents, concerned about pollution and earth tremors. Gaia Vince talks to scientists to find out what fracking involves and what impact it has on the environment, and she discovers what other countries can learn from the pioneers of the technology, the United States.(Image: Views of the Cuadrilla Fracking Site at Balcombe. Credit: WPA Pool, Getty)

We all rely on GPS – the Global Positioning System network of satellites – whether we want to or not. From shipping to taxis to mobile phones, the goods we consume and the technology with which we run our lives depend upon a low-power, weak and vulnerable signal beamed from a few tonnes of electronics orbiting above our heads. This dependence is a new Achilles' heel for the world's financial, commercial and military establishments. From North Korea's concerted disruption of South Korea's maritime and airborne fleet, to white van drivers evading the boss's scrutiny over lunch, this signal is easy to jam - with disastrous consequences. Quentin Cooper meets the scientists and engineers developing alternative, resilient navigation systems.(Image: Captain David Millar, Senior Master, on the bridge of P&O Ferries’ MS Spirit of Britain. BBC copyright)

Deep brain stimulation (DBS) is a brain surgery technique involving electrodes being inserted to reach targets deep inside the brain. Those targets are then stimulated via the electrodes which are connected to a battery powered pacemaker surgically placed under the person's collar bone. Geoff Watts finds out how the technique has been used successfully for treating the movement disorders of Parkinson's disease, in patients with severe, intractable depression, in chronic pain and how it's also being trialled to see if it can also be successful in treating obsessive compulsive disorder (OCD), Tourette's syndrome and other disorders. Geoff meets patients who have had their lives changed by having deep brain stimulation. He also meets the surgeons at the operating table to find out how it works. At the moment no one has all the answers but one psychiatrist he meets says the success of deep brain stimulation means we should radically change the way we understand how the brain works: that the brain is governed by electrical circuitry rather than a chemical soup of neurotransmitters.Picture: Functional brain imaging allows scientists to see inside a living, human brain

Lorna Stewart reports on the new and growing phenomenon of electronic cigarettes and asks if they really help smokers to stop smoking and if they are as safe as their manufacturers suggest. One billion people smoke worldwide and tobacco shortens the lives of half of all users. With consumption of tobacco products increasing globally, finding a way to help smokers to quit is vital. Electronic cigarettes, which contain nicotine in water vapour, are one new approach, but there is very little research into whether they have any harmful effects. As legislators worldwide start to rule on how to regulate them, there are concerns over who might use e-cigarettes; in some places they are proving popular with young people. Issues surrounding nicotine use and addiction have led regulatory bodies around the globe to act, and e-cigarettes are now banned in Brazil, Canada, Singapore, Panama and Lebanon.In this episode of Discovery for the BBC we hear from public health experts, psychologists, and e-cigarette enthusiasts about what e-cigarettes offer and what the risks are.Image: Man exhaling fumes. Credit: Atif Tanvir from ukecigstore

In the 20 years since the release of the film Jurassic Park, DNA cloning technologies have advanced dramatically. Professor Adam Hart asks whether we could and should start bringing extinct animals back from the dead. The fossilised remains of dinosaurs are too degraded to hold any viable DNA, so Jurassic Park is unlikely to be a reality. But what about Pleistocene Park? Deep frozen remains of Arctic animals like the woolly mammoth or the Irish elk, have been shown to contain DNA - but is it in a good enough condition to rebuild the genome and attempt cloning these animals which became extinct nearly 4000 years ago? Some people think it could work. But should we even be considering it? With so many plants and animals threatened with extinction now, should we be wasting time and resources on bringing back animals that didn't make the cut? Adam Hart asks experts in ancient DNA whether the code for life could be resurrected in animals such as the mammoth, the passenger pigeon, the dodo, the marsupial tiger, or the thylacine. And he asks conservationists whether we should be doing it.