Episodes

  • Melvyn Bragg and guests discuss how scientists sought to understand the properties of gases and the relationship between pressure and volume, and what that search unlocked. Newton theorised that there were static particles in gases that pushed against each other all the harder when volume decreased, hence the increase in pressure. Those who argued that molecules moved, and hit each other, were discredited until James Maxwell and Ludwig Boltzmann used statistics to support this kinetic theory. Ideas about atoms developed in tandem with this, and it came as a surprise to scientists in C20th that the molecules underpinning the theory actually existed and were not simply thought experiments.

    The image above is of Ludwig Boltzmann from a lithograph by Rudolf Fenzl, 1898

    With

    Steven Bramwell
    Professor of Physics at University College London

    Isobel Falconer
    Reader in History of Mathematics at the University of St Andrews

    and

    Ted Forgan
    Emeritus Professor of Physics at the University of Birmingham

    Producer: Simon Tillotson

  • Melvyn Bragg and guests discuss theories about the origins of teeth in vertebrates, and what we can learn from sharks in particular and their ancestors. Great white sharks can produce up to 100,000 teeth in their lifetimes. For humans, it is closer to a mere 50 and most of those have to last from childhood. Looking back half a billion years, though, the ancestors of sharks and humans had no teeth in their mouths at all, nor jaws. They were armoured fish, sucking in their food. The theory is that either their tooth-like scales began to appear in mouths as teeth, or some of their taste buds became harder. If we knew more about that, and why sharks can regenerate their teeth, then we might learn how humans could grow new teeth in later lives.

    With

    Gareth Fraser
    Assistant Professor in Biology at the University of Florida

    Zerina Johanson
    Merit Researcher in the Department of Earth Sciences at the Natural History Museum

    and

    Philip Donoghue
    Professor of Palaeobiology at the University of Bristol

    Producer: Simon Tillotson

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  • Melvyn Bragg and guests discuss how members of the same species send each other invisible chemical signals to influence the way they behave. Pheromones are used by species across the animal kingdom in a variety of ways, such as laying trails to be followed, to raise the alarm, to scatter from predators, to signal dominance and to enhance attractiveness and, in honey bees, even direct development into queen or worker.

    The image above is of male and female ladybirds that have clustered together in response to pheromones.

    With

    Tristram Wyatt
    Senior Research Fellow at the Department of Zoology at the University of Oxford

    Jane Hurst
    William Prescott Professor of Animal Science at the University of Liverpool

    and

    Francis Ratnieks
    Professor of Apiculture and Head of the Laboratory of Apiculture and Social Insects at the University of Sussex

    Producer: Simon Tillotson

  • Melvyn Bragg and guests discuss the remarkable achievement of Aristotle (384-322BC) in the realm of biological investigation, for which he has been called the originator of the scientific study of life. Known mainly as a philosopher and the tutor for Alexander the Great, who reportedly sent him animal specimens from his conquests, Aristotle examined a wide range of life forms while by the Sea of Marmara and then on the island of Lesbos. Some ideas, such as the the spontaneous generation of flies, did not survive later scrutiny, yet his influence was extraordinary and his work was unequalled until the early modern period.

    The image above is of the egg and embryo of a dogfish, one of the animals Aristotle described accurately as he recorded their development.

    With

    Armand Leroi
    Professor of Evolutionary Development Biology at Imperial College London

    Myrto Hatzimichali
    Lecturer in Classics at the University of Cambridge

    And

    Sophia Connell
    Lecturer in Philosophy at Birkbeck, University of London

    Producer: Simon Tillotson

  • Melvyn Bragg and guests discuss the ideas and life of one of the greatest mathematicians of the 20th century, Emmy Noether. Noether’s Theorem is regarded as one of the most important mathematical theorems, influencing the evolution of modern physics. Born in 1882 in Bavaria, Noether studied mathematics at a time when women were generally denied the chance to pursue academic careers and, to get round objections, she spent four years lecturing under a male colleague’s name. In the 1930s she faced further objections to her teaching, as she was Jewish, and she left for the USA when the Nazis came to power. Her innovative ideas were to become widely recognised and she is now considered to be one of the founders of modern algebra.

    With

    Colva Roney Dougal
    Professor of Pure Mathematics at the University of St Andrews

    David Berman
    Professor in Theoretical Physics at Queen Mary, University of London

    Elizabeth Mansfield
    Professor of Mathematics at the University of Kent

    Producer: Simon Tillotson

  • Melvyn Bragg and guests discuss the planet Venus which is both the morning star and the evening star, rotates backwards at walking speed and has a day which is longer than its year. It has long been called Earth’s twin, yet the differences are more striking than the similarities. Once imagined covered with steaming jungles and oceans, we now know the surface of Venus is 450 degrees celsius, and the pressure there is 90 times greater than on Earth, enough to crush an astronaut. The more we learn of it, though, the more we learn of our own planet, such as whether Earth could become more like Venus in some ways, over time.

    With

    Carolin Crawford
    Public Astronomer at the Institute of Astronomy and Fellow of Emmanuel College, University of Cambridge

    Colin Wilson
    Senior Research Fellow in Planetary Science at the University of Oxford

    And

    Andrew Coates
    Professor of Physics at Mullard Space Science Laboratory, University College London

    Produced by: Simon Tillotson and Julia Johnson

  • Melvyn Bragg and guests discuss the properties of atoms or molecules with a single unpaired electron, which tend to be more reactive, keen to seize an electron to make it a pair. In the atmosphere, they are linked to reactions such as rusting. Free radicals came to prominence in the 1950s with the discovery that radiation poisoning operates through free radicals, as it splits water molecules and produces a very reactive hydroxyl radical which damages DNA and other molecules in the cell. There is also an argument that free radicals are a byproduct of normal respiration and over time they cause an accumulation of damage that is effectively the process of ageing. For all their negative associations, free radicals play an important role in signalling and are also linked with driving cell division, both cancer and normal cell division, even if they tend to become damaging when there are too many of them.

    With

    Nick Lane
    Professor of Evolutionary Biochemistry at University College London

    Anna Croft
    Associate Professor at the Department of Chemical and Environmental Engineering at the University of Nottingham

    And

    Mike Murphy
    Professor of Mitochondrial Redox Biology at Cambridge University

    Producer: Simon Tillotson

  • Melvyn Bragg and guests discuss the history of real and imagined machines that appear to be living, and the questions they raise about life and creation. Even in myth they are made by humans, not born. The classical Greeks built some and designed others, but the knowledge of how to make automata and the principles behind them was lost in the Latin Christian West, remaining in the Greek-speaking and Arabic-speaking world. Western travellers to those regions struggled to explain what they saw, attributing magical powers. The advance of clockwork raised further questions about what was distinctly human, prompting Hobbes to argue that humans were sophisticated machines, an argument explored in the Enlightenment and beyond.

    The image above is Jacques de Vaucanson's mechanical duck (1739), which picked up grain, digested and expelled it. If it looks like a duck...

    with

    Simon Schaffer
    Professor of History of Science at Cambridge University

    Elly Truitt
    Associate Professor of Medieval History at Bryn Mawr College

    And

    Franziska Kohlt
    Doctoral Researcher in English Literature and the History of Science at the University of Oxford

    Producer: Simon Tillotson

  • Melvyn Bragg and guests discuss how some bats, dolphins and other animals emit sounds at high frequencies to explore their environments, rather than sight. This was such an unlikely possibility, to natural historians from C18th onwards, that discoveries were met with disbelief even into the C20th; it was assumed that bats found their way in the dark by touch. Not all bats use echolocation, but those that do have a range of frequencies for different purposes and techniques for preventing themselves becoming deafened by their own sounds. Some prey have evolved ways of detecting when bats are emitting high frequencies in their direction, and some fish have adapted to detect the sounds dolphins use to find them.

    With

    Kate Jones
    Professor of Ecology and Biodiversity at University College London

    Gareth Jones
    Professor of Biological Sciences at the University of Bristol

    And

    Dean Waters
    Lecturer in the Environment Department at the University of York

    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss the discovery and growing understanding of the Proton, formed from three quarks close to the Big Bang and found in the nuclei of all elements. The positive charges they emit means they attract the fundamental particles of negatively charged electrons, an attraction that leads to the creation of atoms which in turn leads to chemistry, biology and life itself. The Sun (in common with other stars) is a fusion engine that turn protons by a series of processes into helium, emitting energy in the process, with about half of the Sun's protons captured so far. Hydrogen atoms, stripped of electrons, are single protons which can be accelerated to smash other nuclei and have applications in proton therapy. Many questions remain, such as why are electrical charges for protons and electrons so perfectly balanced?

    With

    Frank Close
    Professor Emeritus of Physics at the University of Oxford

    Helen Heath
    Reader in Physics at the University of Bristol

    And

    Simon Jolly
    Lecturer in High Energy Physics at University College London

    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss the contribution of George Stephenson (1781-1848) and his son Robert (1803-59) to the development of the railways in C19th. George became known as The Father of Railways and yet arguably Robert's contribution was even greater, with his engineering work going far beyond their collaboration.

    Robert is credited with the main role in the design of their locomotives. George had worked on stationary colliery steam engines and, with Robert, developed the moving steam engine Locomotion No1 for the Stockton and Darlington Railway in 1825. They produced the Rocket for the Rainhill Trials on the Liverpool and Manchester Railway in 1829. From there, the success of their designs and engineering led to the expansion of railways across Britain and around the world.

    with

    Dr Michael Bailey
    Railway historian and editor of the most recent biography of Robert Stephenson

    Julia Elton
    Past President of the Newcomen Society for the History of Engineering and Technology

    and

    Colin Divall
    Professor Emeritus of Railway Studies at the University of York

    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss the pioneering scientist Rosalind Franklin (1920 - 1958). During her distinguished career, Franklin carried out ground-breaking research into coal and viruses but she is perhaps best remembered for her investigations in the field of DNA. In 1952 her research generated a famous image that became known as Photograph 51. When the Cambridge scientists Francis Crick and James Watson saw this image, it enabled them the following year to work out that DNA has a double-helix structure, one of the most important discoveries of modern science. Watson, Crick and Franklin's colleague Maurice Wilkins received a Nobel Prize in 1962 for this achievement but Franklin did not and today many people believe that Franklin has not received enough recognition for her work.


    With:

    Patricia Fara
    President of the British Society for the History of Science

    Jim Naismith
    Interim lead of the Rosalind Franklin Institute, Director of the Research Complex at Harwell and Professor at the University of Oxford

    Judith Howard
    Professor of Chemistry at Durham University

    Producer: Victoria Brignell.

  • Melvyn Bragg and guests discuss fungi. These organisms are not plants or animals but a kingdom of their own. Millions of species of fungi live on the Earth and they play a crucial role in ecosystems, enabling plants to obtain nutrients and causing material to decay. Without fungi, life as we know it simply would not exist. They are also a significant part of our daily life, making possible the production of bread, wine and certain antibiotics. Although fungi brought about the colonisation of the planet by plants about 450 million years ago, some species can kill humans and devastate trees.

    With:

    Lynne Boddy
    Professor of Fungal Ecology at Cardiff University

    Sarah Gurr
    Professor of Food Security in the Biosciences Department at the University of Exeter

    David Johnson
    N8 Chair in Microbial Ecology at the University of Manchester

    Producer: Victoria Brignell.

  • The octopus, the squid, the nautilus and the cuttlefish are some of the most extraordinary creatures on this planet, intelligent and yet apparently unlike other life forms. They are cephalopods and are part of the mollusc family like snails and clams, and they have some characteristics in common with those. What sets them apart is the way members of their group can change colour, camouflage themselves, recognise people, solve problems, squirt ink, power themselves with jet propulsion and survive both on land, briefly, and in the deepest, coldest oceans. And, without bones or shells, they grow so rapidly they can outstrip their rivals when habitats change, making them the great survivors and adaptors of the animal world.

    With

    Louise Allcock
    Lecturer in Zoology at the National University of Ireland, Galway

    Paul Rodhouse
    Emeritus Fellow of the British Antarctic Survey

    and

    Jonathan Ablett
    Senior Curator of Molluscs at the Natural History Museum

    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss Gauss (1777-1855), widely viewed as one of the greatest mathematicians of all time. He was a child prodigy, correcting his father's accounts before he was 3, dumbfounding his teachers with the speed of his mental arithmetic, and gaining a wealthy patron who supported his education. He wrote on number theory when he was 21, with his Disquisitiones Arithmeticae, which has influenced developments since. Among his achievements, he was the first to work out how to make a 17-sided polygon, he predicted the orbit of the minor planet Ceres, rediscovering it, he found a way of sending signals along a wire, using electromagnetism, the first electromagnetic telegraph, and he advanced the understanding of parallel lines on curved surfaces.

    With

    Marcus du Sautoy
    Professor of Mathematics and Simonyi Professor for the Public Understanding of Science at the University of Oxford

    Colva Roney-Dougal
    Reader in Pure Mathematics at the University of St Andrews

    And

    Nick Evans
    Professor of Theoretical Physics at the University of Southampton

    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss the development of theories about dinosaur feathers, following discoveries of fossils which show evidence of feathers. All dinosaurs were originally thought to be related to lizards - the word 'dinosaur' was created from the Greek for 'terrible lizard' - but that now appears false. In the last century, discoveries of fossils with feathers established that at least some dinosaurs were feathered and that some of those survived the great extinctions and evolved into the birds we see today. There are still many outstanding areas for study, such as what sorts of feathers they were, where on the body they were found, what their purpose was and which dinosaurs had them.

    With

    Mike Benton
    Professor of Vertebrate Palaeontology at the University of Bristol

    Steve Brusatte
    Reader and Chancellor's Fellow in Vertebrate Palaeontology at the University of Edinburgh

    and

    Maria McNamara
    Senior Lecturer in Geology at University College, Cork


    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss why some birds migrate and others do not, how they select their destinations and how they navigate the great distances, often over oceans. For millennia, humans set their calendars to birds' annual arrivals, and speculated about what happened when they departed, perhaps moving deep under water, or turning into fish or shellfish, or hibernating while clinging to trees upside down. Ideas about migration developed in C19th when, in Germany, a stork was noticed with an African spear in its neck, indicating where it had been over the winter and how far it had flown. Today there are many ideas about how birds use their senses of sight and smell, and magnetic fields, to find their way, and about why and how birds choose their destinations and many questions. Why do some scatter and some flock together, how much is instinctive and how much is learned, and how far do the benefits the migrating birds gain outweigh the risks they face?

    With

    Barbara Helm
    Reader at the Institute of Biodiversity, Animal Health and Comparative Medicine at the University of Glasgow

    Tim Guilford
    Professor of Animal Behaviour and Tutorial Fellow of Zoology at Merton College, Oxford

    and

    Richard Holland
    Senior Lecturer in Animal Cognition at Bangor University

    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss enzymes, the proteins that control the speed of chemical reactions in living organisms. Without enzymes, these reactions would take place too slowly to keep organisms alive: with their actions as catalysts, changes which might otherwise take millions of years can happen hundreds of times a second. Some enzymes break down large molecules into smaller ones, like the ones in human intestines, while others use small molecules to build up larger, complex ones, such as those that make DNA. Enzymes also help keep cell growth under control, by regulating the time for cells to live and their time to die, and provide a way for cells to communicate with each other.

    With

    Nigel Richards
    Professor of Biological Chemistry at Cardiff University

    Sarah Barry
    Lecturer in Chemical Biology at King's College London

    And

    Jim Naismith
    Director of the Research Complex at Harwell
    Bishop Wardlaw Professor of Chemical Biology at the University of St Andrews
    Professor of Structural Biology at the University of Oxford

    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss the life and work of Louis Pasteur (1822-1895) and his extraordinary contribution to medicine and science. It is said few people have saved more lives than Pasteur. A chemist, he showed that otherwise identical molecules could exist as 'left' and 'right-handed' versions and that molecules produced by living things were always left-handed. He proposed a germ theory to replace the idea of spontaneous generation. He discovered that microorganisms cause fermentation and disease. He began the process named after him, pasteurisation, heating liquids to 50-60 C to kill microbes. He saved the beer and wine industries in France when they were struggling with microbial contamination. He saved the French silk industry when he found a way of protecting healthy silkworm eggs from disease. He developed vaccines against anthrax and rabies and helped establish immunology. Many of his ideas were developed further after his lifetime, but one of his legacies was a charitable body, the Pasteur Institute, to continue research into infectious disease.

    With

    Andrew Mendelsohn
    Reader in the School of History at Queen Mary, University of London

    Anne Hardy
    Honorary Professor at the Centre for History in Public Health at the London School of Hygiene and Tropical Medicine

    and

    Michael Worboys
    Emeritus Professor in the History of Science, Technology and Medicine at the University of Manchester

    Producer: Simon Tillotson.

  • Melvyn Bragg and guests discuss the life and ideas of Wolfgang Pauli (1900-1958), whose Exclusion Principle is one of the key ideas in quantum mechanics. A brilliant physicist, at 21 Pauli wrote a review of Einstein's theory of general relativity and that review is still a standard work of reference today. The Pauli Exclusion Principle proposes that no two electrons in an atom can be at the same time in the same state or configuration, and it helps explain a wide range of phenomena such as the electron shell structure of atoms. Pauli went on to postulate the existence of the neutrino, which was confirmed in his lifetime. Following further development of his exclusion principle, Pauli was awarded the Nobel Prize in Physics in 1945 for his 'decisive contribution through his discovery of a new law of Nature'. He also had a long correspondence with Jung, and a reputation for accidentally breaking experimental equipment which was dubbed The Pauli Effect.

    With

    Frank Close
    Fellow Emeritus at Exeter College, University of Oxford

    Michela Massimi
    Professor of Philosophy of Science at the University of Edinburgh

    and

    Graham Farmelo
    Bye-Fellow of Churchill College, University of Cambridge


    Producer: Simon Tillotson.