

Unexpected Elements
BBC World Service
The news you know, the science you don’t. Unexpected Elements looks beyond everyday narratives to discover a goldmine of scientific stories and connections from around the globe. From Afronauts, to why we argue, to a deep dive on animal lifespans: see the world in a new way.
Episodes
Mentioned books

Jan 24, 2025 • 49min
Keep it clean
The Hindu festival of Kumbh Mela is currently underway in India. As part of the event, millions of pilgrims will take a cleansing dip in the confluence of the Ganges, Yamuna and the mythical Saraswati.
Inspired by this headline, we splash into a whole bathtub of stories about the science of cleaning.
We find out why it’s so important to prevent contamination of other planets and moons, and how space scientists keep things clean. Next up, we discover how our brains clear out harmful toxins while we snooze.And is there any truth in the saying, ‘tidy house, tidy mind’?Finally, Marnie ponders whether it’s possible to be too clean, or if being a bit grubby is okay.
Presenters: Marnie Chesterton, with Affelia Wibisono and Andrada Fiscutean
Producers: Alice Lipscombe-Southwell, with Dan Welsh, William Hornbrook and Imaan Moin

Jan 17, 2025 • 49min
Circles, circumferences and Covid
After the comic malfunctions of a self-driving car, which drove its passenger/prisoner in endless circles, Unexpected Elements rounds its attention on the humble circle.
Explore how one man calculated the circumference of the Earth 2,000 years before GPS was invented, then be spellbound by the Magic Circle and the mysterious woman who broke into it. And as we hit the five-year anniversary of the Covid pandemic, we take a look at the cycle of infection and mutation, before asking, 'why don’t we have one antiviral pill that kills them all?'
We’re joined by evolutionary psychologist Professor Robin Dunbar, who calculated Dunbar’s number; that is, the maximum number of folks you can hold onto in your circle of friends... five? 500? 5,000? Robin reveals how many REAL friends science says you can have.
Presenters: Marnie Chesterton, with Camilla Mota and Phillys Mwatee
Producers: Harrison Lewis, with Alice Lipscombe-Southwell and William Hornbrook

Jan 10, 2025 • 49min
Scientist spotlight
Team Unexpected have been digging into their mind palaces to pull on the scientific research that has stuck with them most over the past year.
We hear from Professor John Parnell, geologist at the University of Aberdeen, about the role of plankton in forming ancient mountains.
How ocean bubbles play a role in climate regulation with bubble physicist Dr Helen Czerski from University College London. Would you know how to measure the size of a bubble?
We also participate in some memory sports with Jonas von Essen who is a two-time world memory champion. He helps us construct a mind palace in order to memorise really long strings of digits.
Plus we look into the backstory of the human buttocks with science journalist and reporter Heather Radke. She answers the question ‘why do we humans have such large behinds?’
And we hear from Professor Andre Isaacs at the College of the Holy Cross who has filled his chemistry lab with music and dance in order to change perceptions about who can be a scientist.
That, plus many more Unexpected Elements.
Presenter: Marnie Chesterton
Producer: Jonathan Blackwell and Harrison Lewis with Imaan Moin and Alice Lipscombe-Southwell

Jan 3, 2025 • 49min
(Re)New Year
Happy New Year! This week, the Unexpected Elements team is reflecting on 2024 and looking forward to 2025 for renewed chances to spot the northern lights while they're at their peak visibility in this current solar cycle, and we recap on cellular regeneration advancements and regulations in embryonic stem cell models. We chat to Professor Rene Oudmaijer from the Royal Observatory of Belgium who explains that stars also renew themselves... and this process is key to our lovely planet (and ourselves) existing! We also learn all about the potential of bogs and wetlands in the fight against climate change from Professor Christian Dunn of Bangor University. With another amazing year behind us, we reminisce about our favourite stories and listener correspondences in 2024. And finally, we’re wowed by the regenerative ‘superpowers’ of the magnificent axolotl who has the cellular capabilities to re-grow limbs! That, plus many more Unexpected Elements. Presenters: Marnie Chesterton and Caroline Steel
Producers: Harrison Lewis, Imaan Moin and William Hornbrook
Sound Engineer: Duncan Hannant

Dec 27, 2024 • 49min
Festive trash talk
December is a time of celebration, family feuds, and now scientific rivalries. It's also one of the most wasteful months of the year, with festivities in full swing across the globe. No wonder the world is overflowing with rubbish—both literal and metaphorical!Unexpected Elements dives headfirst into the scientific bin to wallow in waste. Could worms be the unexpected heroes of our plastic pollution crisis? How much garbage have we jettisoned into space? And why is part of our very own genome called "junk DNA"?But it’s not all rubbish, we’re also talking trash. While celebrations can bring people together, spending too much time with loved ones can lead to tense moments. Rafi Kohan shares expert tips on how to outsmart your opponent during a heated board game debate.And don’t think trash talk is limited to sports fields. The world of science has its share of drama, too. We’ll explore some of history’s most scandalous squabbles with scientists behaving badly.Come waste an hour with us on Unexpected Elements!Presenter: Caroline Steel, with Chhavi Sachdev and Candice Bailey
Producers: Harrison Lewis, Imaan Moin, Alice Lipscombe-Southwell, William Hornbrook and Eliane Glaser
Sound engineer: Gavin Wong

Dec 20, 2024 • 50min
The science of Santa
As news breaks that archaeologists have found the tomb of St Nick in Turkey, we check in on the North Pole Father Christmas, and fact-check his present giving schedule with advanced level physics and a Gant chart.Plus, prepare for stories of reindeers high... despite their apparent immunity to their favourite hallucinogenic mushroom treats. And we burrow into Santa’s iconic beard to find any microbial magic that lives there.And yet more reindeer magic, this time the mysteries of their amazing body clocks, which they seem to be able to switch on and off at will... AND we reveal Rudolf the red nose reindeer’s big secret. You’ll never hear that song in the same way againPresenter: Marnie Chesterton, with Phillys Mwatee and Camilla Mota
Producers: Emily Knight, Alice Lipscombe-Southwell and William Hornbrook
Sound engineer: Searle Whittney

Dec 13, 2024 • 50min
Totally bananas
Guests Andrada Fiscutean, a Romanian expert in technology and ethical hacking, and Christine Yohannes, a German science reporter, dive into the wild world of bananas. They discuss the recent $6.2 million banana artwork and unveil surprising facts about the fruit, including its slight radioactivity. The conversation shifts to ethical hackers assisting in missing persons cases, showcasing the good side of hacking. Plus, they explore the intriguing Ethiopian False Banana and its nutritional benefits, revealing why it hasn't taken over the world yet.

Dec 6, 2024 • 50min
Going home
This week we’re looking at a political agreement that will hand back sovereignty of the Chagos Islands to Mauritius. In the 1970s, the UK removed the entire Chagossian population to make way for a US military base. The islanders have been fighting for their right to return ever since. If deal can be agreed, the islanders are hoping they will have the chance to go home. And this got us thinking about all things home-related. First up, we discover the intriguing reasons why you can’t smell your own home, then we take a closer look at our homes and all the creatures that live there, before finding out about the ‘home scars’ created by limpets. Next we hear from Dr Nadescha Zwerschke, a scientist who spent time on Rothera research station in Antarctica. She reveals how she made this isolated outpost feel like home. Also, we reveal that global talks to agree a reduction in plastics have collapsed, which could have an impact on all our homes from a pollution perspective.And finally – a type of pasta that would be no good for your homecooked recipes. Presenter: Marnie Chesterton, with Tristan Ahtone and Godfred Boafo
Producer: Alice Lipscombe-Southwell, with Harrison Lewis and William Hornbrook
Sound engineer: Gavin Wong

Nov 29, 2024 • 50min
Doing a deal
It’s Black Friday! Everyone is camping in the street, staying up all night for the very best deals around. And Unexpected Elements are joining in.We take a look at the huge underground trade of vital resources...not run by criminals but fungi.Then it is onto illegal animal trade and the 300 pets who got a terrible deal, strapped to a man’s chest as he tried to make it through airport security. Have you ever asked a pigeon for advice when gambling? We hear from a professor of psychology about why you should not.And finally, the story of Lee Sedol, the world’s best player of the board game Go, who was challenged by Google to a game worth one million dollars. Presenter: Caroline Steel, with Phillys Mwatee and Christine Yohannes
Producers: Emily Knight, Harrison Lewis, Imaan Moin and William Hornbrook
Sound engineer: Searle Whittney

Nov 22, 2024 • 49min
Super Science
The wonders of tardigrades shine as their stunning resilience to extreme conditions is explored. Dr. Joseph Dituri shares insights from his 100-day underwater adventure, shedding light on the effects of isolation. The panel humorously compares nuclear power advancements to superhero antics, while delving into the potential hidden superpowers of cancer survivors. A captivating discussion emerges on how unique plant adaptations lead to groundbreaking medicines, alongside a curious look at wildlife preservation in the Amazon and the surprising science of scents from history.