CrowdScience

In the dead of night at his home in Machinjiri, Malawi, CrowdScience listener John can hear a small, but persistent, hum. Whenever it’s quiet enough, the hum is there – but what’s causing it? And is John the only one who can hear it?Reports of consistent, low-pitched noise have been popping up around the world for decades. No one knows this better than Dr Glen MacPherson, who runs the World Hum Map. He tells presenter Caroline Steel his theory for what’s behind these hums.And Caroline does some investigating of her own. We visit the Isle of Lewis off the coast of Scotland, where residents are reporting a hum. We hear about the impact that persistent noise has on people’s lives, and find out… can Caroline hear the hum too?We also ask why some people can hear a hum but others can’t. We head to an anechoic chamber – one of the quietest places in the world – to speak to Professor Jordan Cheer, who puts Caroline’s low-frequency hearing to the test.From industrial activity to internally generated sounds, we sift through the noise to try and find out what could be causing listener John’s hum.Presenter: Caroline Steel Producer: Sophie Ormiston Series Producer: Ben Motley

James Millen, a quantum scientist and leader at King's College London, joins a panel to decipher the mysteries of quantum mechanics. They tackle mind-bending topics like quantum entanglement, where particles influence each other across distances. Delving into the double-slit experiment, they illustrate light's dual nature as both particle and wave. The discussion unveils how these bizarre behaviors are at the forefront of technological advancements, reshaping our understanding of reality and enhancing quantum computing capabilities.

Can honey help save bees? A deep dive into the intricate relationship between honey production and environmental conservation unfolds. Experts reveal the thriving honeybee populations, yet highlight a worrying decline in wild bee species. Innovative beekeeping practices in Kenya illustrate how honeybees protect elephants and support local farming. The ethical dilemma surrounding honey consumption is examined, while rooftop strategies in urban settings unveil how to bolster wild bee species. Join the conversation on protecting biodiversity and supporting our buzzing friends!

Nazko Stamanov, a Bulgarian science teacher and communicator, dives into the fascinating world of yogurt and fermentation. He discusses whether the ‘live’ cultures in yogurt are still alive when consumed and the health benefits of traditional foods vs. processed options. The conversation explores the cultural pride of Bulgarian yogurt, the risks associated with eating moldy cheese, and how a simple drop of vanilla can flavor an entire liter of milk. Expect delicious insights and a humorous take on food science!

Explore the age-old saying, 'red sky at night, sailor's delight,' and its weather-predicting prowess. Dive into a fun experiment on capturing red skies, comparing results from Canada and the UK. Unravel the science behind atmospheric conditions that create these vivid colors. Discover the blend of folklore and modern meteorology, revealing how historical wisdom has shaped weather predictions. Learn about the roles of pressure systems and light scattering, while considering the limits of using sky hues for reliable forecasting.

Eus van Someren, a sleep expert at the Netherlands Institute for Neuroscience, dives into the complexities of falling asleep. He explains how our bodies signal when it’s time for rest and what factors can affect this process from childhood. The discussion also unveils the possibility of more sleep stages than previously thought and shares fascinating animal sleep rituals that can teach us about our own bedtime routines. Listeners will also find practical tips for overcoming sleep challenges and enhancing their nightly rest.

According to the United Nations Food and Agriculture Organisation, 800 million people are going to bed hungry every night, but 2 billion people in the world are malnourished. Farmers across the globe produce enough food to feed 10 billion people, yet there are only 7.6 billion of us. We know there is enough food to go around, but filling tummies is only the start – we also need a varied diet. CrowdScience visits Nairobi during GGIAR Science Week, a hub for agricultural scientists. They are meeting to discuss the changes needed to get the right crops into the soil and the right food on the plates of those who need it. Presenters Anand Jagatia and Alex Lathbridge are joined by a live audience and a panel of experts Lindiwe Sibanda, Sieglinde Snapp and Alex Awiti. Together they explore questions from our listeners in Kenya and around the world: whether we can restore natural habitats whilst promoting food security; why human waste isn’t used more commonly as a fertiliser; and what impact empowering women in agriculture will have on our ability to feed the world. Recorded at CGIAR Science Week at the UN headquarters in Nairobi. Image: Drone view of tractor ploughing a field Image Credit: Justin Paget via Getty Images Presenters: Anand Jagatia & Alex Lathbridge Producer: Harrison Lewis Editors: Martin Smith & Cathy Edwards Production Co-ordinators: Ishmael Soriano & Josie Hardy Studio Managers: Gayl Gordon, Andrew Garratt & Sarah Hockley

CrowdScience listener Sid is running late, and he’s turning to science to find an excuse. He and his partner Steffi in Singapore have very different attitudes to timekeeping. They wonder if this is down to their different cultural upbringings, or if they just had very different brains to start with. Presenter Chhavi Sachdev puts her own time perception skills to the test to try to understand how subjective our sense of time can be. And we discover how the language we grow up speaking can influence the way we think about punctuality. Presenter: Chhavi Sachdev Producer: Emily Bird Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano Studio Manager: Jackie Margerum

Courtney Shewitt, from the Assiniboine Park Conservancy, shares her insights on sea lions' puzzling habit of swallowing rocks, known as gastroliths. Oliver Wings, director of the Natural History Museum in Bamberg, showcases fascinating discoveries from his vast collection, including surprising finds like gemstones. They discuss the various purposes of gastroliths, such as aiding digestion and buoyancy control. The conversation also touches on other rock-swallowing species, like ostriches and penguins, highlighting the complexity of animal behaviors in this quirky phenomenon.

On the banks of the St Lawrence River in Quebec stands a 100-year-old lighthouse. While initially built to help boats navigate one of Canada’s most difficult waterways, the Point-de-Père site now also holds a different responsibility: it is a key reference for measuring sea levels around the entire North America continent. But this is all set to change. With the development of new satellite technology, the tricky task of measuring sea levels is being updated - which could mean mountains around North America get brand new official heights. In this episode we revisit a question from CrowdScience listener Beth, who wondered about the elevation signs she saw scattered along a mountainous road, indicating how high above sea level she was. As sea levels rise, will all the elevation signs need repainting? And how do you measure sea level, anyway? The height of an enormous pile of rock like Ben Nevis, or Mount Everest feels unchangeable. But we measure them relative to the nearest patch of sea, which is where our story becomes complicated. Unlike water in a bath, sea level is not equal around the world. In fact, nothing on earth - not the sea, the shore or the mountains - is stable or constant, so the question of what you measure from and to becomes incredibly tricky. But that hasn’t stopped scientists risking life and fingers to use an ever-evolving array of technologies to find answers. Join host Marnie Chesterton as she dives into the mechanics of the latest sea level technology, and how it could make a big difference to understanding our unpredictable world. Presenter: Marnie Chesterton Producer: Julia Ravey and Marnie Chesterton Editor: Cathy Edwards Production Co-ordinator: Ishmael Soriano and Jana Holesworth Studio Manager: Emma Harth(Image: Elevation Sign Post, Rocky Mountain National Park. Credit: Stephanie Beverungen via Getty Images.)