Maybe you have a deep, booming voice. Or perhaps it’s light and mellifluous. Some people’s voices are honey-smooth while others are as rough as gravel. But why does your voice sound the way it does? CrowdScience listener Hannah in Berlin is training as a teacher and will be using her voice a lot in the classroom in future. She wants to understand more about it: how can she improve the quality of her voice and protect it? And what factors - physical, genetic and environmental - determine the...

CrowdScience listeners David and Tatiana have long been captivated by an unusual dinner table discussion: the peculiar change they’ve noticed over the past 16 years in the sunlight streaming through their bedroom window in Ostend, Belgium. They’re convinced that the room has not only become sunnier but that the actual angle of sunlight has shifted. Intrigued by their observations, we head to Ostend. Our mission: to investigate three of their theories, enlisting expert help along the...

Fungi are a mysterious and understudied life form. And to add to the intrigue, some of them actually glow in the dark. This phenomenon has sparked CrowdScience listener Derek's curiosity, and he's asked us to investigate. Presenter Caroline Steel gets on the case. This is just one example of the natural wonder that is bioluminescence – living organisms that glow. How do they produce their light, and is there any reason for it? Caroline visits a bioluminescent bay in Puerto Rico, and Dr Brenda...

Can learning new languages make us forget our mother tongue? CrowdScience listener Nakombe in Cameroon is concerned that his first language, Balue, is slipping from his grasp. He has learned multiple languages through his life, but Balue is the language of his family and home. It’s central to his identity and sense of belonging. So why does it seem to be fading from him, and what can he do to get it back? We search for answers, investigating what happens in our brains when we struggle to...

While there is a myriad of deodorants, shower gels and perfumes helping us stay fresh and fragrant today, that hasn’t always been the case. How did humans stay clean in the past, or did they not care so much? And is there an evolutionary reason for human body odour in the first place? These are questions that CrowdScience listener Sarah has pondered on trips in her camper van, when she wants to keep clean, but washing isn’t always convenient. In search of answers, presenter Anand Jagatia...

2024 is the biggest election year in history. From Taiwan to India, the USA to Ghana, by the end of the year almost half of the world’s population will have had the chance to choose who governs them. But there are a huge number of possible voting systems – and listener James wants CrowdScience to find out which is the fairest. To do so, we create a fictional country called CrowdLand to try out different electoral systems. Presenter Caroline Steel consults mathematician David McCune and...

With huge heads on top of spindly stalks, how do sunflowers defy gravity to stay standing? That was a question sent to CrowdScience by listener Frank, whose curiosity was piqued by the towering sunflowers on his neighbour’s deck. They stay up not only when the weather is fine, but, even more impressively, during strong winds. Could this feat of strength, flexibility and balance inspire the construction of tall buildings? It's a question that takes presenter Anand Jagatia to a sunflower...

The Moon and Earth are drifting gradually further apart. Every year the gap between them increases by a few centimetres. We know that the Moon’s gravity has an important effect on Earth - from controlling the tides to affecting the planet’s rotation - but slowly, imperceptibly, over billions of years, that influence will diminish as the Moon moves away. For CrowdScience listener Tony in the UK that idea poses another question. What if we were to look back in time? What effects did the Moon...

18 is the age of majority, or maturity, in most countries around the world. Depending where you live, it might be when you can vote, buy alcohol, or get married. But what's so special about 18 that makes it the beginning of adulthood? CrowdScience listener Lynda didn't feel very mature back then. She recalls a difficult decision that made her wonder what science has to say about when we’re truly grown up. How developed are we, physically, mentally and emotionally, by the age of 18? And how...

An apex predator is a killer. Usually large and terrifying, they enjoy the privilege of life at the top of a food chain. Nothing will eat them, leaving them free to wreak carnage on more vulnerable creatures. In biology, it’s a term normally reserved for animals like polar bears, tigers and wolves. But CrowdScience listener Eoin wonders whether there’s a non-animal candidate for apex predator: the car. After all, worldwide, more than 1.5 million humans die on the roads each year, while...

Many of us experience an inner voice: we silently talk to ourselves as we go about our daily lives. CrowdScience listener Fredrick has been wondering about the science behind this interior dialogue. We hear from psychologists researching our inner voice and discover that it’s something that begins in early childhood. Presenter Caroline Steel meets Russell Hurlburt, a pioneering scientist who devised a method of researching this - and volunteers to monitor her own inner speech to figure out...

It would be quite a superpower to regrow entire body parts. CrowdScience listener Kelly started pondering this after a discussion with her friend on whether human tongues could regrow. Finding out that they couldn't, she asked us to investigate the extent of human regenerative abilities. Presenter Alex Lathbridge travels to Vienna, a hotbed of research in this area. He meets an animal with much better powers of regeneration than humans - the axolotl. In Elly Tanaka’s lab he finds out how she...

Why do we have two eyes? Two ears? Two arms and two legs? Why is one side of the human body – externally at least – pretty much a mirror image of the other side? CrowdScience listener Kevin from Trinidad and Tobago is intrigued. He wants to know why human beings – and indeed most animals - have a line of symmetry in their bodies. Yet, beyond their flowers and fruits, plants don’t seem to have any obvious symmetry. It seems that they can branch in any direction. Anand Jagatia sets out to...

It's a simple metal box that moves nearly all of our goods around the world. Designed for uniformity and interchangeability, the shipping container has reshaped global trade and our lives in the nearly 70 years since its creation. But listener Paul wants to know if these heavy steel containers could be made with lighter materials to cut down on the fuel needed to transport them, especially when they're empty. Could we make shipping containers a more efficient process and reduce the shipping...

When listener Watum heard about the Titan submersible implosion in the news in 2023, a question popped up in his mind: if a machine that we specifically built for this purpose cannot sustain the water pressure of the deep ocean, how do fish survive down there? In this episode, we travel with marine biologist Alan Jamieson to the second deepest place in our oceans: the Tonga trench. Meanwhile, presenter Caroline Steel speaks to Edie Widder about the creatures that illuminate our oceans, and...

CrowdScience listener Azeddine from Algeria has had bad handwriting since he was a child. In fact, it was so untidy that, when he later became a chemistry lecturer, his university students complained that they couldn’t read his lecture notes. That was when he decided he had to do something about it. And it got him wondering… why do some of us have very neat handwriting while other people’s is almost unreadable? Why do his sisters all write beautifully when his natural style is quite the...

In many languages across the world, all nouns are classed as either male or female, or sometimes neuter. The English language, however, only signals gender in its pronouns - he, she, it or they. For inanimate objects, gender just crops up in occasional examples like ships or countries, which, for some reason, are deemed female. This lack of gender in English intrigued CrowdScience listener Stuart, since the other languages he knows all highlight whether something is male or female. Did...

Buildings inspire many emotions, like awe, serenity or even dread. CrowdScience listener Siobhan was struck by this as she passed a huge apartment block with tiny windows; it reminded her of a prison. So, she asked us to investigate the feelings that buildings can trigger. Architects have long considered how the effect of buildings on their occupants or passersby: asking whether certain features elicit feelings of wonder or joy... or sadness and fear. And now modern neuroscience has started...

How do you think about the internet? What does the word conjure up? Maybe a cloud? Or the flashing router in the corner of your front room? Or this magic power that connects over 5 billion people on all the continents of this planet? We might not think of it at all, beyond whether we can connect our phones to it. Another chance to hear one of our favourite episodes, inspired by a question from CrowdScience listener Simon: how much does the internet weigh? First of all, this means deciding...

Snakes are often seen as slithery, slimy and scary. But these intriguing non-legged creatures have made CrowdScience listener Okello from Uganda wonder how they move – more specifically, he wants to know how they climb trees so easily, and so fast. Presenter Caroline Steel meets snake expert Mark O’Shea to investigate the ingenious methods different snakes use to scale a tree trunk, and gets a demonstration from a very agreeable corn snake at a zoo. Snake movement isn’t just your typical...

The CrowdScience team like a challenge. And listeners Jenny and Kai in the UK have come to us with a big one. They want to know how many flies have ever existed. Flies first appeared around 270 million years ago, so presenter Caroline Steel prepares herself to calculate a very, very large number indeed. She enlists the help of Dr Erica McAlister, Curator of Flies at the Natural History Museum in London. As Erica introduces her to specimens from the Museum’s collection of over 30 million...

It’s hard to imagine something as mind-bogglingly small as an atom. But CrowdScience listener Alan has been attempting to do just that. All things in nature appear to be different and unique; like trees and snowflakes, could it be that no two atoms are ever the same? Alan isn’t the first person to wonder this. Philosopher and scientist Gottfried Leibnitz had a similar idea in the 17th century; in this episode, philosopher of physics Eleanor Knox helps us unpick the very idea of uniqueness....

Listener Julie lives close to the coast in New Zealand and wants to know why the water that washes up on the beach isn't fresh. How exactly does all that salt get into the world's oceans? In India, a country where salt became symbolic of much more than well-seasoned food, host Chhavi Sachdev visits coastal salt farms and a research institute dedicated to studying all things saline, to better understand our relationship with salty seas. The team also ventures to a very briny lake on the...

CrowdScience listener Eleanor was lying in bed one rainy evening, listening to the radio. She lives in New Zealand, but happened to hear a weather forecast that told her it was raining in the UK too. She started wondering: could it be the same rain falling there and outside her window in New Zealand? Can a raindrop really travel all the way around the world? There are a number of routes the droplet could take, including traveling as moisture in the air. Presenter Caroline Steel meets...