What makes things sticky? Listener Mitch from the USA began wondering while he was taking down some very sticky wallpaper. Our world would quite literally fall apart without adhesives. They are almost everywhere – in our buildings, in our cars and in our smartphones. But how do they hold things together?
To find out, presenter Marnie Chesterton visits a luthier, Anette Fajardo, who uses animal glues every day in her job making violins. These glues have been used since the ancient Egyptians –but adhesives are much older than that. Marnie speaks to archaeologist Dr Geeske Langejans from Delft University of Technology about prehistoric glues made from birch bark, dated to 200,000 years ago. She goes to see a chemist, Prof Steven Abbott, who helps her understand why anything actually sticks to anything else. And she speaks to physicist Dr Ivan Vera-Marun at the University of Manchester, about the nanotechnologists using adhesion at tiny scales to make materials of the future.
Presented by Marnie Chesterton. Produced by Anand Jagatia for BBC World Service
This episode was originally broadcast on 2nd October 2020
Which is better: Optimism or pessimism?
In most cultures, the soundtrack to our lives is one of optimism. We are told to aim for the stars, dream big and believe that tomorrow will definitely be a better day. But why do so many people subscribe to the cult of 'glass half full' when life’s hardships should make any reasonable person a bit more wary?
Listener Hannah from Germany - a self-described pessimist - is intrigued as to whether the optimistic way of life is really the best way to be. Taking on the challenge is Marnie Chesterton, who finds out why 80% of the population have an optimism bias and how the ability to hope and take risks may have helped the human species get where it is today. She also meets a man who pushes the optimistic outlook to its very limits - Base jumping world champion, Espen Fadnes. Listener Hannah on the other hand looks into the psychology of pessimism to find out if there are any advantages to her less rose-tinted view on life - and whether the culture we grow up in shapes how realistically we see the world.
Producer: Caroline Steel
Presentet: Marnie Chesterton
Espen Fadnes – Freefall professional
Tali Sharot – Professor of neuroscience, UCL
Julie Norem - Professor of psychology, Wellesley College
Jeanne Tsai - Professor of psychology, Stanford
(Image: Two arrows, one with a sad smiley and the other with happy smiley, pointing in opposite directions. Credit: Getty Images)
Would my cat survive in the wild?
Cats started hanging out with humans thousands of years ago, and nowadays these fluffy, lovable pets are found in many of our homes. But there is no doubt lots of them still have keen hunting instincts - witness all the birds and small mammals they kill each year.
CrowdScience listener Rachel started wondering whether her cat Eva could fend for herself while watching her uncoordinated swipes at a toy on a string, and seeing her fall off the sofa. Even though Eva was once a stray, she now lives entirely indoors, and it is hard to imagine her holding her own back on the mean streets. But could this pampered pet recover her survival instincts? Or would she go hungry, or fall foul of other cats or predators?
Cat behaviour expert Roger Tabor is on hand with answers. His pioneering ‘cat-navs’ shine a light on what cats get up to inside and outside the home; we meet one of his subjects, a tiny cat with a fierce personality. Roger explains how a cat’s survival toolkit depends on their sex, breed, and above all their early life. Environment matters, too, so in Japan, where Rachel and her pet cat live, we visit a cat shelter to learn about the day-to-day challenges stray cats face.
And just how ‘domestic’ are our cats, anyway? How different are they from their wildcat cousins, and how did they come to be our companions in the first place? It turns out beguiling humans might be even more of a survival trick than hunting.
Presenter: Melanie Brown
Producer: Cathy Edwards
Roger Tabor – Chartered Biologist and Cat Behaviourist
Jamie Baker – Head Keeper, Battersea Park Children’s Zoo
Dr Eva-Maria Geigl – Research Director, CNRS (French National Centre for Scientific Research)
Susan Roberts and Cheryl Nodhturft-Mori – Japan Cat Network
(Image: Cat in Lion costume. Credit: Getty Images)
Can we recycle concrete?
Concrete is the most widely used substance on earth after water. It’s quite literally the foundation of the modern world, and no wonder - it’s strong, cheap, and mouldable into nearly any shape.
But these benefits come at a cost: concrete production is responsible for around 8% of global CO2 emissions - that’s around three times more than the aviation industry.
Concrete might not look pretty, but given its carbon footprint, should we be more careful about how we use it? And rather than throwing waste into landfill, could we recycle it instead? That’s what Crowdscience listener Catherine wants to know.
To investigate, Marnie Chesterton and Anand Jagatia learn more about what makes concrete such a brilliant and versatile material. It’s down to the chemistry of how cement dries – which, it turns out, is anything but boring. They find out how the stuff is made, and why that produces so much carbon. And they hear about some ingenious projects to repurpose demolition waste – including creating underwater habitats for marine life, and using 3D printers to turn crushed concrete into street furniture.
With Prof John Provis, Prof Becky Lunn, Chris LaPorta, Sheryl Lee, Dr Edward Randviir and David Lacy
Presented by Marnie Chesterton and Anand Jagatia.
Produced by Anand Jagatia for BBC World Service
[Image: Discarded Concrete, Credit: Getty Images]
Can COP26 deliver on climate change?
The science is unequivocal: human-made climate change is leading the world into an environmental crisis, and time is running out to prevent permanent damage to ecosystems and make the planet uninhabitable for many of us humans.
As communities around the world increasingly experience the devastating effects of global warming, world leaders, policy makers and scientists from all over the globe are attending COP26, the United Nation’s major climate summit in Glasgow, Scotland. Each nation will be frantically negotiating its commitments to tackling emissions - many agree it’s a pivotal moment for the future of humanity.
Crowdscience hosts a panel of three experts taking part in the conference, to hear their thoughts on what progress has been made so far. They answer listener questions on rising sea levels, explaining that a temperature rise of more than 1.5 degrees won’t just affect small island nations but will have serious consequences for every country in the world. We hear about an interactive atlas developed by the Intergovernmental Panel on Climate Change (IPCC) that shows the impact of higher temperatures in different regions.
And presenter Marnie Chesterton asks about the financial barriers that have prevented many people from traveling to COP26 and discovers why it’s vital that people from the global south have their voices heard.
Ko Barrett, Vice-chair of the Intergovernmental Panel on Climate Change (IPCC)
Dr Saleemul Huq, Director of the International Centre for Climate Change and Development in Bangladesh(ICCCAD)
Dr Tara Shine, Director of Change By Degrees
Produced by Melanie Brown and Marijke Peters for BBC World Service.
[Image: Delegates in the Action Zone at COP26 UN Climate Summit, Glasgow. Credit: Getty Images]