CrowdScience

When CrowdScience listener, Grady, crashed violently on his motorbike in the desert, he thought he was going to die. Years later he still can’t remember the dramatic seconds just before the impact. Where did the memory disappear to? Did the hard hit to the head knock his memories out or are they still in his brain somewhere? CrowdScience turns to brain science to find out if those last few seconds are lost for good or if the brain tells a different story.

Under normal circumstances our brains like to hold onto memories that are emotionally important to us. We can remember our wedding day but not yesterday’s breakfast. But scientists have discovered that during near-death experiences, our brains are flooded with chemicals that disrupt our ability to remember. Grady may never recall how he was able to keep his motorbike steady as he drove off the road because – maybe – the memory was never created in the first place.

Presenter: Marnie Chesterton Producers: Melanie Brown and Louisa Field Sound design: Eleni Hassabis

(Image: A biker helmet lies on street near to a motorcycle accident. Credit: Getty Images)

Human sexuality comes in many forms, from exclusively heterosexual to exclusively homosexual. But seeing as homosexuality creates apparent reproductive and evolutionary disadvantages, listener Ahmed from Oslo wants to know: why are some people gay?

CrowdScience presenter Caroline Steel examines what science can - and can't - tell us about the role of nature, nurture and evolution in human sexual attraction. She asks a geneticist what we know of the oft-debated 'gay gene', as well as looking into why homosexual men on average have more older brothers than heterosexual men.

Caroline looks into the role of nurture with a developmental psychologist to answer a question from a CrowdScience listener from Myanmar. He wonders if the distant relationship he has with his own father has impacted his own feelings of attraction.

She also learns about research into a group of people in Samoa who may shed light on the benefits of traditionally non-reproductive relationships for communities as a whole.

Presented by Caroline Steel Produced by Jonathan Blackwell for BBC World Service

Contributors: Dr. Kevin Mitchell - Associate Professor of Genetics and Neuroscience, Trinity College Dublin Dr. Malvina Skorska - Postdoctoral Fellow at the Centre for Addiction and Mental Health, Toronto Prof. Lisa Diamond - Professor of Psychology and Gender Studies, University of Utah Prof. Paul Vasey - Professor and Research Chair, Department of Psychology, University of Lethbridge Vaitulia Alatina Ioelu - Chief Executive Officer, Samoa Business Hub

(Photo credit: Ahmed Umar)

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

CrowdScience listener Kristine from Wisconsin in the USA wants to know why herbs and spices taste so good to so many of us. She’s intrigued to know if there's evidence that herbs and spices can keep us healthy.

Anand Jagatia visits the historic naval city of Portsmouth in the UK, where exotic spices from around the world were first brought in from the East Asia more than 600 years ago.

He’s on a journey to find out why many of us think spices are delicious. But are there also nutritional benefits to seasoning our food with them? Anand asks what science or studies are there to show that eating herbs and spices can be beneficial for our health?

Presenter: Anand Jagatia Producer: Joanna Hall Assistant Producer: Jonathan Harris Editor: Richard Collings Studio Technicians: Bob Nettles & Steve Greenwood

Contributors:

Prof. Lindell Bromham, evolutionary biologist, Australian National University Dr. Kanchan Koya, Molecular Biologist and founder of the Spice Spice Baby website Dr. Beronda L. Montgomery, plant biologist and Dean at Grinnell College, Iowa, USA Dr. Lorenzo Stafford an olfactory researcher, Department of Psychology, University of Portsmouth, UK

(Photo: A couple stand at a spice shop. Credit: Thomas Barwick / Getty Images)

When planning to have a baby, women are expected to give up everything from smoking to alcohol, even soft cheese. But the other half of fertility comes from the sperm, usually provided by a man. So should men also give up their vices to improve the quality of their sperm, and their chances of conception? That’s what Listener Stuart in Australia wants to know. He emailed CrowdScience after he and his wife had been trying to have a second child for two years. He gave up alcohol, and coffee, but wants to know if there is any hard science to back up the idea that this would improve his fertility.

To find out, presenter Anand Jagatia speaks with Professor Allan Pacey, a scientist who specialises in the study of male fertility and sperm. He discovers that male subfertility accounts for 50% the problems with getting pregnant. And we’re far from alone. Sperm is a remarkably diverse, but also fragile cell. Across the animal kingdom, different species have problems with male fertility, but have adapted novel ways to improve their chances of reaching the egg.

Men often struggle to speak about their fertility, and reporter Chhavi Sachdev tells Anand the impact this has on couples in India who struggle to conceive, or don’t want to. She speaks with fertility specialist Professor Nirmal Kumar Lohiya about how this reticence to speak about fertility is changing.

Viruses from Mumps to HIV have long been known to target the delicate sperm production cells in the testicles. Dr Krutika Kuppalli tells Anand why, and what we know about the possible impact of SARS CoV-2 on male fertility.

Professor Allan Pacey gives Anand and Stuart some advice for what to do while trying to conceive - don’t wear tight underwear - and get used to talking about your swimmers or even getting them checked out.

Contributors: Professor Allan Pacey - Andrologist at the University of Sheffield in the UK. Dr Nicolla Hemmings, expert on bird sperm, Royal Society Dorothy Hodgkin Research Fellow at the University of Sheffield, UK. Professor Nirmal Kumar Lohiya, Fertility specialist and co-developer of RISUG male contraceptive, University of Rajasthan, India Dr Krutika Kuppalli, Assistant Professor at the Medical University of South Carolina, USA

Chhavi Sachdev, Reporter and presenter for CrowdScience

Presented by Anand Jagatia, Produced by Rory Galloway

(Image: Sperm cells Credit: Getty images)