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BBC World Service


We take your questions about life, Earth and the universe to researchers hunting for answers at the frontiers of knowledge.


CrowdScience

For their fans, jigsaw puzzles are a satisfying challenge, a focus, a chance to put everything else aside for a moment and be creative. But for other people they’re a frustrating jumble of random shapes and colours, a pointless task which is best left in the box.
 
CrowdScience listener Heather is definitely a fan. She loves doing jigsaw puzzles and she wants to know why some people are so good at them. What skills do you need to find a pattern amongst all those shapes and colours? How do our brains, eyes and hands assemble the fragments into the finished article? And why do we enjoy doing them anyway? 
 
Presenter Alex Lathbridge puts together the pieces to answer Heather’s question. He sits down to work on a jigsaw with Sarah Mills, the ten-times UK jigsaw puzzling champion (yes... competitive jigsaw puzzling really is a thing!) As he watches Sarah complete the puzzle at lightning speed he gets a few of her top tips. 
 
So what’s going on in our brains when we’re doing a jigsaw puzzle? How do we recognise and process colour and shape? Prof Mark Mattson from Johns Hopkins University in the USA has the answer. And it’s all to do with a little seahorse-shaped part of the brain called the hippocampus. 

Alex also explores the effect of jigsaws on our brains with neuropsychologist Dr Patrick Fissler. He’s carried out research to investigate the benefits of jigsaw puzzles on our brains as we grow older. 

Both listener Heather and ten-times-champion Sarah seem to be better at jigsaws than Alex is. So, based on that sample size of three, women are superior puzzlers compared to men! But has anybody actually cast the net wider to see if that’s really the case? Alex talks to Daniela Aguilar from the University of Lethbridge in Canada about her study to investigate exactly that – and she reveals the results. 
 
Heather’s also wondering if any other species enjoy puzzles. And it seems they do! Alex meets Dr Cody McCoy from the University of Chicago to find out about the optimistic, tool-using crows of New Caledonia. From crows to competitive puzzlers, it seems we all relish a challenge!

Presenter: Alex Lathbridge
Producer: Jeremy Grange
Editor: Cathy Edwards
Studio Manager: Bob Nettles
Production Co-ordinator: Ishmael Soriano

Why am I good at jigsaw puzzles?

It seems bizarre to seek out experiences that are uncomfortable or downright painful. Yet examples abound: it’s common to eat painfully hot chillies, drink bitter coffee, or ‘feel the burn' when exercising - and enjoy it.
 
CrowdScience listener Sandy is baffled by this seemingly counterintuitive phenomenon, and has asked us to investigate. Presenter Anand Jagatia turns guinea pig as he tests a variety of unpleasant sensations, and unpicks the reasons we’re sometimes attracted to them. 
 
He meets chilli-eating champion Shahina Waseem, who puts Anand’s own attraction to spicy food to the test. Food scientist John Hayes explains how our taste receptors work and why our genes affect the appeal of bitter food. Neuroscientist Soo Ahn Lee describes her research looking at what happens in participants’ brains when they eat chocolate and capsaicin, the chemical that makes chillies hot.
 
As for the ‘pleasurable pain’ we sometimes experience when exercising, sports doctor Robin Chatterjee reveals the secrets of the ‘runner’s high’, while neuroscientist Siri Leknes explains why the feeling that something’s good for us can make discomfort pleasurable.
 
Presenter: Anand Jagatia
Producer: Jo Glanville
Editor: Cathy Edwards
Production co-ordinator: Ishmael Soriano
Sound engineer: Sue Maillot

(Image: Young man have bath in ice covered lake in nature and looking up, Czech Republic Credit: CharlieChesvick via Getty Images)

Why does pain sometimes feel good?

The Moon has always sparked human curiosity. It governs the tides and biological rhythms. It’s inspired myths and stories. It’s inspired us to reach out and explore it. And it's certainly inspired CrowdScience listeners, who have sent us a host of questions about it. And in a special lunar-themed episode we’ve brought together a panel of astronomers and planetary scientists to help answer them. 

What would life be like if there was no Moon? Would there even be life? Or what if we had two moons? Are the Moon and Earth equally battered by meteors? What would happen if an asteroid collided with the Moon? And could the Moon ever escape Earth’s gravity? 

Anand Jagatia is joined by Prof Sara Russell, Head of the Planetary Materials Group at the Natural History Museum in London; Prof Neil Comins from the University of Maine, author of the book What if the Moon didn’t Exist?; and Prof Katarina Miljkovic from Curtin University in Perth, Australia. 

Presenter: Anand Jagatia 
Producer: Jeremy Grange 
Editor: Cathy Edwards 
Production Co-ordinator: Ishmael Soriano 
Studio Manager: Andrew Garratt

(Photo: Landscape with the rising of the full moon during the golden hour Credit: Jose A. Bernat Bacete via Getty Images)

Will the Earth ever lose its Moon?

Did you know that flies fly in rectangles, fish hide by lighting themselves up and the moon is lifting the ground underneath your feet? Anand Jagatia quizzes members of the CrowdScience team on the moments from the past year that had them scratching their heads in amazement. 

We hear Dr Erica McAlister’s attempts to calculate how many flies have ever existed, and about flies’ mating choreography, courtesy of Prof Jochen Zeil. We learn how to tell a mosquito’s sex thanks to Eggrey Aisha Kambewa and Dr Steve Gowelo. 

Astronomer Dr Darren Baskill describes tides not of water but of land; Dr Edie Widder paints a vivid picture of a camouflaged creature of the deep; and we explore starfishes’ five-fold symmetry with Dr Imran Rahman. 

Khimlal Gautam, Mountaineer and Chief Survey Officer for the Government of Nepal, tells us of the near-death experience he had when checking the height of Mount Everest. 

And finally, axolotl expert Dr Elly Tanaka is astonished at the dedication of CrowdScience presenter Alex Lathbridge to the subject of her research. 

Presenter: Anand Jagatia 
Producer: Ben Motley 
Editor: Cathy Edwards 
Production Co-ordinator: Ishmael Soriano 
Studio Managers: Donald MacDonald and Giles Aspen

(Photo: Lost in formulas Credit: Cimmerian via Getty Images)

I didn’t know that!

When listener Diana fell on a run on her birthday, her first instinct was not to check her bruised hand, but instead to get up as quickly as possible and act as if nothing had happened. She felt embarrassed. Meanwhile, her son Marley loves to watch fail videos that, mostly, show people falling over. So why does falling – something that can cause serious injury – elicit both embarrassment and laughter? 

In the name of CrowdScience, presenter Caroline Steel trips, stumbles and falls. She spends a morning with clown Sean Kempton who teaches her slapstick skills, including how to do it safely. 

Psychologist Rowland Miller explains why falling can be embarrassing and shares his theory of why humans have developed this emotion in the first place. Then it’s time for Caroline to try out Diana’s predicament herself. If a BBC presenter falls in a park, will she feel embarrassed? 
 
From embarrassment to laughter, psychologist Janet Gibson lists the ingredients of a funny fall, and humour expert Caleb Warren explains how they can get funnier with distance. Then Caroline tries, semi-successfully, to make members of the public laugh. Will clown Sean do a better job? 

Presenter: Caroline Steel 
Producer: Florian Bohr 
Editor: Cathy Edwards 
Production coordinators: Ishmael Soriano
Sound engineers: Bob Nettles, Tim Heffer and Giles Aspen

Why am I embarrassed when I fall?

In the past stout beer has been touted for its supposed health benefits. Is there any truth to those claims - and what happens if you take the alcohol out?

CrowdScience listener Aengus pondered these questions down at the pub, after noticing most of his friends were drinking non-alcoholic beers. He wondered how the non-alcoholic stuff is made – what’s taken out and what’s added in – and whether the final product is better for you than the alcoholic version.

It’s a question that takes us to Belgium, home to the experimental brewery of a global drinks company which takes the growing market for alcohol-free beer very seriously. David De Schutter, head of research and development, shows host Marnie Chesterton how to take alcohol out of beer without spoiling the flavour.

We also find our way to a yeast lab in Leuven, Belgium where Kevin Verstrepen and his team have found another way to make alcohol-free beer with the help of industrious microbes: yeast varieties that brew beer without producing any alcohol in the first place. And how do they compare to the alcoholic versions? We discuss the importance of aromas in our perception of beer’s taste.

So should listener Aengus stick to non-alcoholic stout? We speak to scientist Tim Stockwell about the health drawbacks of alcohol, even in moderation. And gut microbiome researcher Cláudia Marques fills us in on her delicious pilot study, which looked at the effects of both non-alcoholic and alcoholic beers on our digestive tract. 

Along the way, Marnie taste-tests what's on the market, and asks the experts why this particular grocery shelf has become so much bigger and more flavourful in recent years.

Presenter: Marnie Chesterton
Producer: Sam Baker
Editor: Cathy Edwards
Production co-ordinator: Ishmael Soriano
Technical producers: Giles Aspen, Andrew Garratt and Donald MacDonald

(Image: Close-up of waitress holding craft beer at bar, Brazil Credit: FG Trade via Getty Images)

Is beer better without alcohol?

Carbon footprints are a measure of how much we each contribute to the greenhouse gases that warm the Earth’s atmosphere. The global average of carbon dioxide emissions is nearly 5 tonnes per person per year, although it can be triple that in certain countries. 

But one CrowdScience listener in Ghana is wondering about the bigger picture. After all, humans aren’t the only species on this planet. So which other animal has the biggest carbon footprint? 

CrowdScience presenters Caroline Steel and Marnie Chesterton are on the case, examining and arguing over the animal that deserves the top spot for this title. 

Caroline, a vegan, points to the cow as the top contender, since the livestock sector produces 14.5% of total greenhouse gas emissions, and cows, whether as meat or dairy animals, are responsible for the majority of that. The team look at initiatives around the world to be more efficient with each animal out there. But maybe it’s time to put another sector in the spotlight? Pets. We love our dogs and cats but do their meat-based diets win them a place on the podium? 

From most loved to most detested, we look at the role that key pests play in upsetting the carbon budget. Could a small beetle with a large appetite for greenery be an unusual winner, thanks to the trees these pests destroy over their lifetimes? 

Is the biggest offender a carbon footprint, hoofprint, pawprint, or clawprint? 

Presenters: Caroline Steel and Marnie Chesterton 
Producer: Marnie Chesterton 
Editor: Cathy Edwards 
Production co-ordinator: Ishmael Soriano 
Technical producers: Sarah Hockley and Donald MacDonald

Which animal has the biggest carbon footprint?

While watching a feisty cockatoo chase after a hawk, CrowdScience listener Alison saw the hawk catch a thermal and rise effortlessly into the sky. The cockatoo gave chase, but the hawk climbed higher and higher until it became just a tiny speck, barely visible to the naked eye. 

And that got Alison thinking: just how high can birds go? Are there altitude limits for our feathered friends? Could a cockatoo, a sparrow, or even a duck reach such dizzying heights if they really put their wings to it? 

Presenter Alex Lathbridge sets out to investigate. Biologist Catherine Ivy reveals that life above the clouds isn’t easy. At high altitudes, the air is thinner, oxygen is scarce, and wings don’t generate as much lift. But some bird species have evolved incredible adaptations to overcome these challenges. 

Among them: bar-headed geese, renowned for their daring flights over the world’s tallest mountains. Physiologist Lucy Hawkes delves into how these geese defy the odds with their remarkable physiology, revealing the surprising discoveries she made while putting some of them on a treadmill. 

From super-powered hearts to clever lungs, we uncover the secrets behind nature’s impressive aviators. 

Presenter: Alex Lathbridge 
Producers: Ilan Goodman and Jeremy Grange 
Editor: Cathy Edwards 
Production co-ordinator: Ishmael Soriano 
Technical producer: Sarah Hockley

(Image: OIE A TETE BARREE (Anser indicus) EN VOL Credit: Jean-Patrick DEYA / Contributor via Getty Images)

How high can birds fly?

Smartwatches are increasingly popular and many of us use these wearable devices to monitor our performance and improve our fitness. But how reliable is the data they collect, and can they actually make us healthier? 

CrowdScience listener Caitlin from Malawi is a big fan of her smartwatch. Her husband Fayaz, however, is much more sceptical of its accuracy, and has asked us to investigate. We meet up with them both at the gym, where Caitlin and presenter Caroline Steel put their fitness trackers – and themselves – to the test. 

We visit public health researchers Dr Cailbhe Doherty and Rory Lambe, who investigate the accuracy of wearable consumer devices, at University College Dublin. Caroline again pushes herself to the limit to see how her smartwatch results measure up to those from gold standard laboratory equipment. 

But is it crucial for smartwatches to be accurate? If they get us off the couch, is that what makes the difference to our health? Health behaviour expert Dr Ty Ferguson from the University of South Australia has studied this very question. And finally, how does quantifying our every move affect the way we think about ourselves and how we live? Professor Deborah Lupton from UNSW Sydney, shares some insights. 

Presenter: Caroline Steel 
Producers: Jo Glanville and Sophie Ormiston 
Editor: Cathy Edwards 
Technical producer: Sarah Hockley 
Production co-ordinator: Ishmael Soriano

Is my smartwatch good for my health?

Some of our biggest achievements happen in the first years of our lives. Taking our first steps, picking up a complex language from scratch, and forming relationships with some of the most important people we’ll ever meet. But when we try to remember this period of great change, we often draw a blank. 

After losing his Dad aged four, CrowdScience listener Colin has grappled with this. Why can’t he recall memories of such a monumental figure in his life, yet superficial relationships from his teens remain crystal clear in his mind? Colin takes presenter Marnie Chesterton to visit some of the significant locations of his childhood, places he would have spent many hours with his late father; and he recounts his earliest memories.

On this trip down memory lane, Marnie discovers the psychological reason behind our lack of early childhood memories comes down to a phenomenon known as infantile amnesia. Tomás Ryan, neuroscientist at Trinity College Dublin, discusses some of the theories behind this universal experience, and Sarah Power from the Max Planck Institute for Human Development discusses her groundbreaking study exploring this form of forgetting in real time. Elaine Reese from the University of Otago digs into how our environment and culture can influence the age of our earliest memories, and why some of the first things we remember might not be the big, huge events you’d expect. And we hear about fascinating new insights from animal studies that hint these memories could still be lurking inside our heads... 

Presenter: Marnie Chesterton 
Producer: Julia Ravey 
Content Editor: Cathy Edwards 
Production Co-ordinators: Ishmael Soriano & Josie Hardy
Technical producer: Emma Harth

(Photo: Marnie Chesterton and CrowdScience listener, Colin, on the swings in Belfast.)

Why am I embarrassed when I fall?

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