Curious Cases

Why does my heart not ache after exercise? asks listener Keith. Rutherford and Fry explore how and why heart muscle cells are special.Dr Mitch Lomax is a sports scientist at the University of Portsmouth. She helps actual Olympic swimmers get faster. She explains how most of the muscles attached to our skeletons work: Tiny fibres use small-scale cellular energy, which, when all these fibres work in concert, turns into visible muscular movement. Mitch also explains how the dreaded Delayed Onset Muscle Soreness, or DOMS, can hit, taking a stair-wincing 48-72 hours to peak after exercise.But skeletal muscles turn out to be quite different to heart muscles, as consultant cardiologist Dr Rohin Francis explains. Heart cells are more efficient and don't get fatigued like skeletal muscle cells. They are extremely energetic and 'just want to beat'. He also explains that the sensory feedback from the heart muscles is different too. They have a different sort of nerve supply, with fewer sensory nerves, so that there is less chance of pain signals being sent to the brain.However, heart cells' incredible abilities are counterbalanced by one Achilles-like flaw: They cannot easily heal. Professor Sanjay Sinha is a British Heart Foundation (BHF) Senior Research Fellow and a Professor in Cardiovascular Regenerative Medicine at the University of Cambridge. His job is to fix broken hearts and he explains to Adam how new research into stem cells could be used to fix normally irreparable heart cells.Presenters: Hannah Fry and Adam RutherfordProducers: Jennifer Whyntie and Fiona RobertsFirst broadcast on BBC Radio 4 in October 2021.

“I don’t really understand why water has so many properties on different scales ranging from very large and cosmic to very small quantum and quarky - Could you help by zooming in and out on water to explain what is known about it? "Asks Neil Morton in Stirling. “Why does boiling water sound different to cold water?’ asks Barbara Dyson in Brittany in FranceOllie Gordon, in Christchurch in New Zealand, wants to know ‘why water is essential for all life as we know it?’And many more questions on the weirdness of water are tackled by super science sleuths Hannah Fry and Adam Rutherford. With assistance from: * Quantum physicist Professor Patricia Hunt, at the Victoria University in Wellington in New Zealand* Science writer and author of ‘H2O – a biography of water’ Philip Ball* Physicist and bubble expert in the Department of Mechanical Engineering at UCL, Dr Helen Czerski.Producer: Fiona RobertsFirst broadcast on BBC Radio 4 in October 2021.

“I don’t really understand why water has so many properties on different scales ranging from very large and cosmic to very small quantum and quarky - Could you help by zooming in and out on water to explain what is known about it?" asks Neil Morton in Stirling. Rutherford and Fry learn about the special hydrogen bonds that makes water such an unusual liquid.Quantum physicist Professor Patricia Hunt, at the Victoria University in Wellington in New Zealand explains to Hannah the quantum properties of individual water molecules and how they link up with other water molecules in liquid water and solid ice. She describes the hydrogen bonds that give water some of it’s weird and wonderful properties such as why ice floats, why water is able to store huge amounts of heat and why water has such a strong surface tension.Science writer and author of ‘H2O – a biography of water’ Philip Ball describes how in the 18th century it was discovered that water was not one of the classical elements, but a compound liquid of water and hydrogen and explains to Adam why there are at least 15 different types of ice.Physicist Dr. Helen Czerski sets the record straight on how ice forms in oceans and lakes and why water is at its densest at 4 degrees Centigrade and not zero.Presenters: Hannah Fry & Adam RutherfordProducer: Fiona RobertsFirst broadcast on BBC Radio 4 in October 2021.

How do guide dogs know where they're going? It's not like their handler whispers in their ear and asks to go to the pharmacy, maybe the toothpaste aisle. So how does it work? asks Charlotte, aged 42. Dogs and humans have gone paw in hand for thousands of years. Historic and genetic evidence shows we’ve shaped each other's existence over millennia. But dogs were only first trained as guides for blind people in the UK 90 years ago. What’s the biology behind this extraordinary partnership? Hannah heads to Guide Dogs UK’s training school in Royal Leamington Spa. She meets up with expert Graham Kensett to find out what it takes to make a guide dog from nose to tail, starting from before birth and following the life course through to retirement. Hannah also meets the delightful Wendy and Wilmott, a German shepherd and a retriever cross. Despite both still growing into their ears, they show her their already extraordinary skill set, from tackling obstacle courses to safely crossing roads. Cool, calm, patient, unflappable: Guide dogs are the astronauts of the canine world. But, as trainer Jenna explains, it’s all in the partnership with the owner, who needs to do plenty of work in terms of training and learning routes to journey in harmony with their furry guide.Richard Lane has owned guide dogs for over 25 years, and confirms this first hand. He reveals just how he gets to the toothpaste aisle, and tells Adam how at its peak a partnership can navigate London Waterloo station better than some sighted people, even at rush hour. Richard also explains how deeply felt the bond that forms between owner and dog is, and describes the hardest part of guide dog ownership: Letting go at the end. Presenters: Hannah Fry & Adam Rutherford Producer: Jen WhyntieA BBC Audio Science Unit production for BBC Radio 4

It was a dark and stormy night. A secret message arrived addressed to Rutherford & Fry from a mysterious woman called Heidi Daugh, who demanded to know: "Why do people like to be scared? For example, going on scary amusement park rides and watching horror movies that make you jump.”What followed was an investigation, which would test our intrepid duo to their very limits. They explore the history of horror, starting with its literary origins in the Gothic fiction classic 'The Castle of Otranto'.Adam challenges Hannah to watch a horror film without hiding behind a cushion. She quizzes horror scholar Mathias Clasen to find out why some people love the feeling of terror, whilst it leaves other cold.Sociologist Margee Kerr and psychologist Claudia Hammond are also on hand to explore why scary movies are so powerful and popular. Then Rutherford and Fry investigate the more physical side of fear, when they delve into the history of roller coasters to investigate why we enjoy being scared.Never ones to shy away from a challenge, the pair attempt to channel their inner adrenaline junkies with a trip on one the UK's scariest roller coasters at Thorpe Park.David Poeppel from New York University studies the science of screaming, and we discover what makes screams uniquely terrifying. Plus, psychologist and broadcaster Claudia Hammond describes some early experiments which tested how fear affects our body.This episode is a remake of two earlier broadcast episodes.Producers: Fiona Roberts & Michelle Martin Presenter: Adam Rutherford & Hannah FryFirst broadcast on BBC Radio 4 in February 2021.

Why are some people left-handed, whereas the majority are right handed? Rutherford and Fry revisit The Sinister Hand episodes to further investigate handedness in humans and animals. They considered cockatoos, chimpanzees and Hannah's dog, Molly, to discover that humans are unique, with just one in ten of us being left-handed.They ask if there is an evolutionary reason for just 10% of the human population being southpawsHannah talks to primatologist Prof Linda Marchant from Miami University about Neanderthal teeth and termite fishing.Adam consults handedness expert Prof Chris McManus from University College London. He's been trying to track down the genes responsible for whether we're right or left handed.And what about left-handed brains or eyes or molecules?Prof Andrea Sella explains handedness, or chirality, at the molecular scale and why when we consider Thalidomide, something seemingly so trivial can be extremely important.They also explore the left-handed brain. Some researchers point to a link between left-handedness and impairments like autism or dyslexia. Others claim that lefties are more creative and artistic.So what's the truth? The team consults Professors Sophie Scott, Chris McManus and Dorothy Bishop to find out.This episode is an updated version of two earlier broadcast episodes.If you have any Curious Cases for the team to investigate please email curiouscases@bbc.co.ukProducers: Fiona Roberts & Michelle MartinPresenter: Adam Rutherford & Hannah FryA BBC Audio Science Unit production for BBC Radio 4, first broadcast in 2021.

The doctors continue their investigation into gravity, and answer Peter Fraser’s question: Is dark matter a proper theory or just a fudge to fit existing 'proper' theories to otherwise inexplicable observations?Whilst scientists are pretty convinced our understanding of gravity is largely correct, there are still some significant gaps. Namely, given the way galaxies are observed to behave, around 85% of the matter that they think should be in our universe is missing. So where – and, as importantly, what – is it? Cosmologist Andrew Pontzen introduces the evidence from our observations of the cosmic microwave background, light leftover from the Big Bang, which indicate that dark matter exists.However, this evidence alone is not enough for science. Physicist Chamkaur Ghag is trying to find particles of dark matter here on Earth. Unsurprisingly, no-one is quite sure where these critters are hiding in the particle zoo of protons, neutrons, electrons, quarks, bosons, muons and the rest – or even what they look like. One theory suggests a weakly interacting massive particle, or WIMP, may be the dark matter minibeast. Hundreds of thousands of these could be flying through our fingertips every second. To tell whether they’re there, Cham and hundreds of scientists are building detectors, huge vats of liquid xenon in underground caverns.Bond villain-esque lairs don’t come cheap, and listener Peter’s query is valid – what if dark matter goes the same way as the aether, an all-permeating (and ultimately non-existent) material that was hypothesised to carry light through the vacuum of space? Astrophysicist Katy Clough reiterates that experiments are the way to test predictions. Building a picture of how gravity works continues to take many people enormous effort, but this is the scientific process.Presenters: Hannah Fry & Adam RutherfordProducer: Jen WhyntieA BBC Audio Science Unit production for BBC Radio 4, first broadcast in 2021.

The doctors investigate a millennia-old query, as listener Emma in New Zealand asks: ‘How does gravity pull us?’People have been thinking about how gravity works for a very long time. Way longer than when that particular apple almost certainly didn’t fall on the head of Isaac Newton. Cosmologist Andrew Pontzen begins guiding us through our journey by taking us back to the almost entirely incorrect writings of ancient Greeks.We then fast forward past Galileo and Newton, and throw in an extra dimension. Using an all-too-believable analogy where some merry cyclists suddenly ride into a meteor crater, astrophysicist Katy Clough tells us how Einstein’s spacetime works. Limitations of analogies accepted, this explains some of the observations that didn’t fit with Newton’s workings alone. But there are other snags with our understanding of gravity, both at the very small quantum scale and the very large galactic scale. Physicist Chamkaur Ghag introduces what scientists think may account for some of these issues: the mysterious dark matter.Presenters: Hannah Fry & Adam RutherfordProducer: Jen WhyntieA BBC Audio Science Unit production for BBC Radio 4, first broadcast in February 2019.

Do individuals perceive time differently? Psychologist and presenter of All in the Mind, Claudia Hammond wrote the book ‘Time Warped – Unlocking the Mysteries of Time Perception’. She explains how emotion and memory are big factors in how time is perceived. She stresses how time can stretch and squeeze depending on whether you are looking backwards or forwards. And she explains how lockdown has warped time in different ways for different people.Professor David Eagleman, from Baylor College of Medicine in Houston, conducted a very famous experiment on time dilation, to see whether time slows down when you are very frightened. He wanted to see whether people actually have increased time resolution during a terrifying moment, and tested whether his students actually see in slow motion when they leapt off a tall building (in a safe manner).Professor Marc Whitman is a neurologist who has spent his career looking for the clock in our brains. He says that time is dealt with in many parts of the brain, with some parts dealing with different durations, from milliseconds to decades. Katya Rubia is Professor of Cognitive Neuroscience at Kings College London and is an expert on time perception in children with ADHD. She links the impulsiveness of children with Attention Deficit Hyperactivity Disorder to problems with time perception and has found that the pre frontal lobe, which is key for perceiving time is both functionally and structurally different in children with the disorder, which means that time goes much slower for them. This goes some way to explain their impatience and inability to sit still.Producer: Fiona RobertsPresenters: Dr Hannah Fry and Dr Adam RutherfordA BBC Audio Science Unit Production for BBC Radio 4, first broadcast 2021.

The doctors put mosquitoes on trial, as listener Cathy in the UK asks, ‘What is the point of mosquitoes?’ in response to our show about wasps. Mosquitoes have undeniably played a role in killing millions of people. Malaria is the single biggest cause of death in human history. But Erica McAlister, senior curator of flies and fleas at the UK’s Natural History Museum, reveals that not all mosquitoes are interested in biting us for a blood meal, or are involved in transmitting disease. Only the females of about 10 species are the most problematic for humanity, from around 3600 true species of mosquito. Limited research indicates that many play important roles in ecosystems, for example as pollinators on land and as food sources during their larval stage in aquatic environments.Nonetheless, those roughly 10 species cause devastating disease. Kate Jones’ research at University College London examines the interface of ecology and human health. Malaria and dengue fever alone cause over 300 million infections annually. And there are many more diseases transmitted by mosquitoes: Zika, West Nile fever, Yellow fever, Japanese encephalitis – the list goes on, and with urbanisation and climate change, the picture is constantly changing. So what can be done? Should we try to annihilate the disease-carrying species? Insecticide use has historic and ongoing controversy, as the difficulties of needing to stop deaths in the short term risks longer term environmental damage, with unforeseen and possibly greater consequences for humanity. So Adam turns to new, genetic technology with zoologist Matthew Cobb. Can and should we modify mosquitoes to wipe themselves out, by wrecking local populations with sterile males, or use a technique called a gene drive to perpetuate debilitation through generations? Or could life find a way to evolve past our attempts at control, and cause greater problems? The doctors deliberate and try to decide a verdict on mosquitoes’ fate.Presenters: Hannah Fry & Adam RutherfordProducer: Jen WhyntieA BBC Audio Science Unit production for BBC Radio 4, first broadcast in 2021.