We generate a huge amount of noise, whether it’s our rumbling roads, pumping parties, or talkative tourists. And the topic of noise also generates a lot of questions from our listeners. In this episode we explore three of them, with the help of acoustic scientist Kurt Fristrup and neuropsychologist Catherine Loveday. Listener Dominique finds it hard to experience even one minute of a natural soundscape without some intrusion of human-made noise. He wonders how noise pollution is affecting both the natural world and us humans. We discuss just how noisy our modern world is, and visit a National Park in California to hear how they’re encouraging more peace and quiet there. Meanwhile Michelle, having witnessed her husband wince in pain at the sound of squeaking takeaway boxes, asks why certain noises are particularly unpleasant or even painful to some people. And finally, Jennifer has a sonic mystery for us to solve: why does the time of day make such a difference to the distant noises reaching her remote home? With contributions from Professor Catherine Loveday, Dr Kurt Fristrup and Mia Monroe. Additional audio courtesy of the U.S. National Park Service/Patrick Myers, Dominique Laloux, and Boise State University/Jesse Barber. Presenter: Anand Jagatia Producer: Cathy Edwards Studio Managers: Bob Nettles and Jackie Margerum

From Lawrence of Arabia to Star Wars via tales of intrepid adventurers traversing lonely sand-swept landscapes, deserts have always had a powerful pull on the popular imagination. But if a desert is full of sand, where did all that sand come from in the first place? That is what CrowdScience listener Andy wants to know, so presenter Caroline Steel heads off into the dunes to find out. She begins by finding out what a desert is anyway and whether it is always sandy, as well as tracing the flow of material across the huge, ever-shifting sand seas of the Sahara. From deserts fed by sand from mountains thousands of kilometres away, to dunes migrating across the entire continent of Africa, Caroline discovers how sand has just the right properties to be carried along by the wind. She also explores how the sand in every desert has a unique fingerprint, and finds out how fish bones in the Sahara tell the story of its lush, green past. Contributors: Dr Jo Nield, University of Southampton Dr Andreas Baas, Kings College London Dr Andrea Zerboni, University of Milan Presented by Caroline Steel Produced by Ben Motley for the BBC World Service (Photo: The Sahara desert near Timbuktu, Mali Credit: Jeff Overs)

When falling in love or fancying someone, one emotion can dominate over the rest: jealousy. Some may try to play it cool and act aloof, but seeing - or even thinking - of a romantic partner engaging with others can lead people to act completely out of character. The green-eyed monster can hijack thoughts for days to weeks on end, spending precious energy ruminating on situations that may never arise. So why is it that humans feel jealousy? Do people experience this emotion differently? And are there ways to stop it? CrowdScience presenter Caroline Steel sets about answering these questions from listener Odile in France, who has struggled with all-consuming jealousy in some romantic relationships. She hears about a kind of monkey who get jealous of their own reflection from Professor Karen Bales at University California Davis. A trip to ZSL London Zoo sees more monkeys, but these are more bothered about protecting the vital friendships which aid their survival. Dr Alex Mielke from the University of St Andrews explains how these interactions can give us an insight into why jealousy exists. Some of us get more jealous than others and are more likely to act out of character when the green-eyed monster takes hold. Caroline completes a detailed questionnaire to see how jealous she really is, and gets advice from Julia in South Africa, who is in a polygamous marriage and has had to handle romantic jealousy. The nature-nurture balance of jealousy is untangled by geneticist Dr Laura Wesseldijk from Amsterdam UMC (who reveals some surprising information about the first author on her research paper…) and psychologist Dr Johan Ahlen from the Karolinska Institute rounds off the programme discussing how the future of jealousy management could look like for those who struggle. Presenter: Caroline Steel Producer: Julia Ravey

When CrowdScience listener Eric spotted a few gnats flying around on a milder day in mid-winter it really surprised him - Eric had assumed they just died out with the colder weather. It got him wondering where the insects had come from, how they had survived the previous cold snap and what the implications of climate change might be for insect over-wintering behaviour? So he asked CrowdScience to do some bug investigation. CrowdScience presenter Marnie Chesterton takes up the challenge and heads out into the British countryside – currently teeming with buzzes and eight legged tiny beasties - to learn about the quite amazing array of tactics these small creatures use to survive the arduous days of cold. She hears how some insects change their chemical structure to enhance their frost resistance whist others hanker down in warmer microclimates or rely on their community and food stocks to keep them warm. But cold isn’t the only climatic change insects have to endure, in the tropics the seasons tend to fluctuate more around wet and dry so what happens then? Marnie talks with a Kenyan aquatic insect expert who describes how mosquitoes utilise the rains and shares his worry climate change could have a big impact on insect populations. Contributors: Dr Erica McAlister – Entomologist and Senior Curator, Natural History Museum, Dr Adam Hart – Entomologist and Professor of Science Communication - University of Gloucestershire Fran Haidon – Beekeeper Laban Njoroge – Entomologist, head of the Invertebrate Zoology – Museum of Kenya Dr Natalia Li – Biochemist Presenter: Marnie Chesterton Producer: Melanie Brown [Image: Butterfly in winter resting on snow covered branch. Credit: Getty Images]

ow do we stay up when we ride a bicycle? Lots of us can do it without even thinking about it, but probably very few of us can say exactly HOW we do it. Well, CrowdScience listener Arif and his children Maryam and Mohammed from India want to understand what’s going on in our heads when go for a cycle, and how we learn to do it in the first place. Presenter Marnie Chesterton is on the case, tracking down a neuroscientist studying how our brains and bodies work together to keep us balanced whether we’re walking or trying to ride a bicycle. She learns about the quirks of bicycle engineering from researchers in the Netherlands who are part of a lab entirely devoted to answering this question. In the process falling off of some unusual bicycles and uncovering the surprising truth that physics might not yet have a proper answer. And we peer deeper into our brains to find out why some memories last longer than others, whether some people can learn quicker than others and the best way to learn a new skill. Presented by Marnie Chesterton and Produced by Emily Bird for the BBC World Service. Featuring: Kathleen Cullen, Johns Hopkins University, USA Jason Moore, University of Technology Delft, The Netherlands Lara Boyd, University of British Columbia, Canada Rado Dukalski, University of Technology Delft, The Netherlands Josie and Freesia, Pedal Power [Image: Family riding bikes. Credit: Getty Images]