How good are you at finding your way from A to B? Humans throughout history have used all sorts of tools to get us to our destination – from a trusty map and compass to the instant directions on a smartphone. But CrowdScience listener Pam from Florida wants to know what happens when we leave the surface of the Earth and try to navigate our way around space. Is there a North and South we can use to orientate ourselves? Which way is left if your nearest landmark is a million light years away? And if you can’t tell which way is up, how do spacecraft know where they’re going?

Presenter Anand Jagatia speaks to experts in an attempt to find his way through the tricky problem of intergalactic space navigation.

Contributors:

Climate change and biodiversity loss are two of the biggest threats humanity has ever faced - and tackling them is going to take a whole lot of collaboration and putting others before ourselves. But are humans cut out for this level of cooperation? Or are we fundamentally too self-interested to work together for the common good?

Listener Divyesh is not very hopeful about all this, so he’s asked CrowdScience if humans have a “selfish gene” that dooms us to failure when trying to meet these challenges. He's worried that humans are destined by our evolution to consume ever more natural resources and destroy the environment in the process.

But while it's true that humans often act in our own interest, we also show high levels of cooperation and care. Could tapping into these beneficial behaviours help us solve our global problems? Marnie Chesterton goes on the hunt for the best ways to harness human nature for the good of planet Earth - from making sure the green choice is always the cheaper and easier option, to encouraging and nurturing our better, altruistic and collaborative sides.

We visit a rural mountain community in Spain to see the centuries-old system they have for sharing common resources; while in the city, we meet activists figuring out how to live a more community-spirited and sustainable urban life. And we speak to experts in evolution, ecology and psychology to find out what helps nudge us into greener habits.

Presenter: Marnie Chesterton. Produced by Cathy Edwards for BBC World Service.

Image Credit: Getty Images

How is a small budget pocket radio able to recreate all the atmosphere and sounds of a football match? CrowdScience listener Andy wants to know about the science enabling his radio listening, so presenter CrowdScience Geoff Marsh sets off - microphone in hand - to follow the journey of sound on the radio.

Starting with the microphone, Geoff learns how acoustic energy is converted into electrical signals. Then BBC World Service presenter Gareth takes Geoff to a little-known room in the BBC called the Radio Shack. Gareth demonstrates how these electrical signals are attached to radio waves before being sent over the airwaves and they take a radio kit apart to understand how these waves are received and converted back into sound waves.

Finally, Geoff visits an acoustic lab at Salford University where he hears a demonstration of ‘object based audio’. This technology could enable us to create our own bespoke mix of dramas and sports, such as heightening the commentary sound or choosing to hear just the crowd, just by using the everyday speakers many have lying around them, such as mobile phones.

Tune in and join us!

[Image Credit: Getty Images]

Scientists have been searching for dark matter for decades, and think there’s six times more of it in the universe than the stuff we can actually see, like stars and planets. But they still don’t know what it is. So how can we be sure dark matter really exists? And why does it matter, anyway?

With Professor Malcolm Fairbairn, Dr Chanda Prescod-Weinstein, Dr Chamkaur Ghag and Professor Katherine Freese.

Presented by Marnie Chesterton

Produced by Graihagh Jackson and Cathy Edwards

We live in a world where bigger is often seen as better - and the size of someone's brain is no exception. But a listener in Nairobi wants to know, does size really matter when it comes to grey matter? CrowdScience presenter Marnie Chesterton is on a mission to find out if the physical attributes of our head and brain can tell us anything about what's going on inside. We certainly thought so in the past.

In the 1800s, phrenology – determining someone’s characteristics by their skull shape – was very fashionable and curator Malcolm MacCallum gives us a tour of the extensive phrenological collection of death masks and skulls in Edinburgh’s anatomy museum. It's a 'science' that's now been completely debunked. Yet there’s no escaping the fact that over our evolutionary history, human brain size has increased dramatically alongside our cognitive capabilities.

But is it the whole story? Rick Potts, Director of the Human Origins Program at the Smithsonian tells of the point in time when human brains expanded the most; a time when the climate was changing, resources were unreliable and the intelligence to be adaptable might mean the difference between life and death. Adaptability is also key to Professor Wendy Johnson’s definition of intelligence, although she points out that IQ test, flawed as they are, are still the best predictor we have for intelligence… and that, yes, there is a weak correlation between having a larger head, and doing better at IQ tests. Why is that? We don’t know, says Dr Stuart Ritchie from KCL. According to him, neuroscientists are only in the foothills of understanding how a physical difference in the brain might underpin a person’s psychology. But researching this could offer valuable insights into how our amazing brains work.

[Image: Brain being measured. Credit: Getty Images]

“I’m bored!” We can all relate to the uncomfortable - and at times unbearable - feeling of boredom. But what is it? Why does it happen? And could this frustrating, thumb-twiddling experience actually serve some evolutionary purpose? CrowdScience listener Brian started wondering this over a particularly uninspiring bowl of washing up, and it’s ended with Marnie Chesterton going on a blessedly un-boring tour through the science and psychology of tedium. She finds out why some people are more affected than others, why boredom is the key to discovery and innovation, and how we can all start improving our lives by embracing those mind-numbing moments.

Featuring: Prof James Danckert (University of Waterloo, Canada), Dr Elizabeth Weybright (Washington State University), Dr Christian Chan (Hong Kong University) and Annie Runkel (University of Dundee).

Presented by Marnie Chesterton

Image: Young Asian girl feeling lonely and bored at home. Screen addiction withdrawal symptoms (Credit: Oscar Wong, Getty Images)

Should you wash your eggs? Well believe it or not, there is quite an international debate about this question from CrowdScience listener Susan. In Canada, where Susan grew up, commercially sold eggs are washed before they reach stores, whereas in the UK where she is now living they are not. So what is best to avoid contamination?

It’s one of a number of egg-themed questions that CrowdScience tries to crack in this episode. One of our presenters, Marnie Chesterton, heads over to Susan’s home in London to cook some eggs and explore other egg cooking questions from our listeners, such as what is the science behind frying an egg without it sticking to the pan and why are some boiled eggs harder to shell than others?

Meanwhile this episode’s other presenter, Anand Jagatia, explores questions about eggs after they have hatched. He investigates a case of curious chicken behaviour sent in by listener Laurie, as well as working out how a cuckoo knows it’s a cuckoo when it’s been raised in another bird’s nest.

Presented by Marnie Chesterton and Anand Jagatia

Featuring: Dr. Vincent Guyonnet, Dr. Valérie Lechevalier, Dr. Siobhan Abeyesinghe and Dr. Ros Gloag

(Photo credit: Getty Images)

Raindrops on roses and whiskers on kittens – CrowdScience has covered a lot this year. And what better way to see out 2021 than to look back at a few of our (and your!) favourite things? Great questions are right at the top of the team’s list – especially with the way that for every one we answer, five more appear in our inbox!

So for a festive treat, Marnie asks the crew to answer three of them. What's the sun's role in our sense of direction? Why are we so uncomfortable with other people’s sadness? And why does listening to the radio make us sleepy? (Or is it just too much eggnog…?) From our favourite listener advice on how to keep your Christmas lights untangled to why cold swimming could activate your Vagus nerve, tune in for new questions and more CrowdScience favourites to light up your holiday season!

Presented by Marnie Chesterton and many members the CrowdScience Team – Melanie Brown, Marijke Peters, Caroline Steel, Hannah Fisher, Samara Linton and Anand Jagatia.

Featuring:

• Haneul Jang, post-doctoral researcher, the Max Planck Institute for Evolutionary Anthropology

As many of us gear up for the annual Christmas feast, some of you may be wondering how to eat everything before it goes off. It’s a great question, as the UN puts global food waste at a whopping 1.3 billion tonnes a year – that’s one third of all edible produce being thrown in the bin.

So this week the team investigates listener Peter’s query about what makes some fruit and vegetables rot faster than others. Preserving food used to be about ensuring nomadic populations could keep moving without going hungry, but these days some things seem to have an almost indefinite shelf-life. Is it about better packaging or can clever chemistry help products stay better for longer? A Master Food Preserver explains how heat and cold help keep microbes at bay, and how fermentation encourages the growth of healthy bacteria which crowd out the ones that make us ill.

Presenter Datshiane Navanayagam learns how to make a sauerkraut that could keep for weeks, and investigates the gases that food giants use to keep fruit and veg field-fresh. But as the industry searches for new techniques to stretch shelf-life even further could preservatives in food be affecting our microbiome? Research shows sulphites may be killing off ‘friendly’ gut bacteria linked to preventing conditions including cancer and Crohn’s disease.

Produced by Marijke Peters for BBC World Service.

Featuring:

Christina Ward, Master Food Preserver

Life is full of choices, from the mundane (like what to wear today) to the critical (how should we deal with the pandemic?). So how can we make the best decisions? That’s what listener David wants to know.

To investigate, Caroline Steel learns how being smarter doesn’t necessarily make you a good decision maker. She speaks to researchers about the importance of ‘gut feelings’ – and how certain people with no intuition whatsoever can struggle to make choices. She also learns why it’s easier to give advice to other people than to follow it yourself, and how we can work together to make the best decisions in a group.

Presenter: Caroline Steel

Contributors: