Walk the line

0:00This BBC podcast is supported by ads outside the UK. Fall tastes better with better ingredients from Whole Foods Market. No added growth hormones are antibiotics in their meat department. Means slow-bray short ribs are even more satisfying. All-sea food is well caught like their vibrant sockeye salmon or verified responsibly farmed. And all sweets, including fall-themed cookies, are made without high-fructose corn syrup. Spice up fall at Whole Foods Market. I love a brighter smile. What I don't love is that little wince when I take a sip of something cold or even breathe in cold air. You know that feeling? It takes your breath away that s-ouch! Eek! That's why I like sense-adiene clinical white. It's triple-action formula whitens, holishes, and helps protect against sensitivity. Plus, it protects against new stains for up to six months. So I can keep enjoying my iced coffee and everything else I love without the sensitivity.

1:01Wider teeth without the wince. Try sense-adiene clinical white today. Last year I took a trip to Niagara Falls, and I was reminded that as well as being a stunning natural wonder, this border between Canada and the US is also a magnet for tight-rope walkers. In some parts of the world like Armenia, theatrics on a highwire are elevated to an art form, like ballet but more dangerous. At Niagara, the high-line walkers seem to be more in the business of show. Frenchman Charles Blondin crossed the gorge more than 300 times from 1859. Italian Maria Spelterini is the only woman to have crossed the falls, and she did it, blindfolded, handcuffed, and one time with her feet in Peach Farmers harvesting buckets. But my favourite detail is from the last guy to cross, Nick Wallender. In 2012, Nick crossed not

2:04just the gorge, but over the furiously churning white waters of the falls, and he had to get special permission from both the American and the Canadian governments to do this, and on arrival at the Canadian side had to present his passport. I'm Monty Chesterton from the BBC World Service, this is Unexpected Elements. And joining us again, hot off the heels from last week's show we have tech journalist Andrada Fiskatani in Bucharest Romania. Welcome back. Wala Mani, hello. And in Nairobi, Kenya, broadcaster and journalist Michael Kaloke, hello, hello. How about you, Mani? This is the panel. We are the team. We are also the science programme inspired by the news. So each week we scour the headlines for a story that hooks us in, and then we use that

3:04to bounce off into lots of unexpected sciencey directions. Without further ado, this is the story. We've got lined up this week. Main challenge is the technical one. Doing it for 15 years, I do get fear. Estonian slackline at Jan Rus performs a daring show 120 metres above the streets of central soul. I feel the other side, it feels great. Yes, last week, Estonian athlete and slackline world champion Jan Rus carried out a spectacular acrobatic performance across a 160 metre long high line, strong 120 metres above the streets of central soul. Androda, Michael, how do you feel about this? Are either of you fellow daredevils?

4:06Not really, Mani. Thinking about Rus being up there, sends chills down my spine. Where about you, Michael? Well, Mani, some of my friends have called me a daredevil, I guess for being an ice and snow carving competitor. A bit of the daring aspect of it is using chainsaws and chisels when you're up there in freezing temperatures. So, yeah, I guess I'd call myself a little bit of a daredevil. Yeah, well, the daredevil high line walk is our starting point. We're going to bounce off from there into some science. Androda, where would you like to take us? Well, we know there's a big difference between me and Michael. And we've known for a while that some people seem more willing to take risks than others. But a question is, can you look at someone's brain and tell whether they are a risk taker? Or can a brain scan tell whether someone drinks too much or drives too fast or does other risky things? I mean, I feel like you wouldn't ask if the answer were no.

5:13Well, in 2021, a paper came out in nature human behavior. It was written by researchers at the University of Pennsylvania and the University of Zurich. And they looked at brain scans from almost 13,000 people in the UK, most of them middle aged and older adults. And these people also reported things like how much they smoke, how much they drink, or how fast they drive. And the researchers repeated the entire analysis in a second, separate group of 13,000 more. Okay, and what did the scans show? The researchers combined reports of smoking, drinking, speeding, and number of sexual partners into a score. And saw that people with higher values, so those who smoked or drinked more tended to have lower gray matter volume in several brain regions. Gray matter is the major tissue in the brain. It contains the cell bodies of millions

6:18of neurons, the nerve cells that control our thinking, processing, and movement, right? Exactly. And in this study, the researchers measured the volume of gray matter. And this isn't the same as measuring how well the brain works. Researchers saw tiny differences in several brain areas, in the omigdala, for instance, which is involved in feelings of fear, and the hippocampus, which helps us create new memories. Okay, so if I brought you my scan, do you think you might be able to tell what kind of driver I am? Not exactly. So first, less gray matter doesn't automatically mean someone makes worse decisions. Also, the effects in the study are small, and these are averages across thousands of people. Okay, so you said first and second. Second, there are still a lot of questions that have not been answered. That same brain scan database, it's called the UK

7:19Biobank has been examined by other researchers studying risky behavior. And everyone looked at slightly different things. One group found stronger activity in the origin of the brain just above the eye sockets, the medial orbidofrondyl cortex. But these researchers measured how activity fluctuated there rather than how much gray matter people had. Okay, so the picture isn't settled. Let me push you on something though, but the study included people who'd been smoking and drinking, some of them for decades. I mean, isn't the simple explanation that smoking and drinking changed the brain? It is, and this is a good point, but that study did control for alcohol consumption and still found the same results. However, there's a very different paper published in 2024, and here an American team looked at the brains of nearly 10,000 children at around age 10 and followed them for

8:21several years. Some of those children did go on to drink, smoke or take drugs. So the researchers went back to the original scans and they saw some differences already there. In those people who used substances, they saw thinner cortex at the front, but thicker cortex elsewhere and larger brain volume overall. Oh, tantalizing. So they're seeing differences, but I mean, what does that tell us? It tells us that some brain differences can precede substance use. It doesn't prove they caused it, and it does not rule out changes caused by later use. And also, I should point out the effects were small. I think parents will tell us they'll probably know by the edge of eight whether their child is a risk taker already. I think it's one of those things that you can kind of tell whether you've got a cautious child after a few years, right? Anyway, to me, it sounds like, and we say this a lot, more research is needed, right, Andrada? That's right. So we've gone from daredevil slat

9:28liners to risk takers having less gray matter. Where would you like to take us next, Michael? So, Marney, we've just talked about me being an ice copter. So I'm super interested in design and engineering. And this story about Ian Roo's walking between two tall buildings got me thinking about how skyscrapers deal with the wind. Oh, okay, I've seen enough videos of skyscrapers moving in the wind to not want to ever live in a skyscraper. So how does wind affect a tall building, Michael? Well, wind forces, which are known as wind loads, have a greater impact on my building as it becomes taller and taller. So the steel and concrete used in a skyscraper structure is designed to bend and flex to absorb the impact that these wind loads have. But it's a bit more complicated than that. When large box like skyscrapers become prevalent in countries like the United States, they brought with them a whole host of wind loading engineering challenges.

10:31Now, as wind moved around the top of these tall structures, vortices were created in a process known as vortex shedding. And vortex shedding? Well, now, flowing air can act differently, depending on what obstacles are in its path. In the case of these buildings, their blocky walls created a blunt obstacle that wind had to kind of flow around. Now, as strong winds blew around these structures, areas of low pressure emerged on the opposite side of them, creating suction forces that pulled at these buildings, causing them to move back and forth, that sort of sway emotion. Now, this even led to a noticeable swaying and shaking for people inside the building. So you can imagine that. Yes, I can imagine that. Androda, can you imagine that? It sounds pretty scary to me if I'm going to go in a vacation in the near future. I'll remember not to book a room in one of these places. Michael, how did the engine is deal with this issue?

11:33They came up with this approach called corner softening. Now, this is where sharp edges of a building are smoothed off to make it more aerodynamic. Creating at twists in a building can also reduce or in some cases eliminate the locations where vertices can form. An example of this technique can be seen in the 632 meter high Shanghai tower in China. You can even increase the porosity of a building by literally cutting off parts of the structure to allow air to flow through. Is there one method in particular that caught your attention, Michael? Yes, Yes, Androda, I think for me, perhaps based on my interest in sculpting, it is the tapering of a building as it rises, which breaks up the uniformity that causes vortex shedding. An example where this method has been used is Kuala Lumpur's Petronas towers and also the Shard in London, which I believe you're familiar with, Marnie. Absolutely. I cycle past that

12:33on a weekly basis and that's got a sort of tapering top like a like a shard like a shard of ice. Ah, well sounds interesting. Something maybe I should carve one day. Absolutely. Any other techniques? So, okay. This particular technique is pretty wild. So some skyscrapers contain tuned mass dampers. Now they're often near the roof or upper floors. These are huge weights that are connected to the main building by cables or springs. A bit like a clock pendulum, they move in the opposite direction to the building sway, basically counteracting the motion and creating a more stable environment for those inside and also reducing the risk of damage during earthquakes. Now the Taipei 101 building in Taiwan and the Trump World Tower in New York both use this method. Thank you, Michael. So a high line feet, 120 meters above sole, inspired a dig around in the

13:34brains of risk takers and we've just heard how some tall buildings contain massive pendulums or have their corners shaped off to make them sway less. Listeners, any thoughts on what you've heard today? You can email unexpected at bbc.co.uk or you can send a WhatsApp message. Our number is plus 444-330-678-3080. Still to come, what sort of rodent makes a surprisingly good robot? Find out after this. Ella here with this week's unexpected elements quiz. News of a daring slackline traversal, 120 meters above the ground has had our head in the clouds. At high altitudes where the air is thinner and there is lower atmospheric pressure, the human body can be put under a lot of strain. But there are also some benefits to living at higher altitudes. For example, some diseases are less likely to occur. So my question is which of these diseases has lower rates among people

14:39living 1500 meters above sea level? A diabetes b chronic kidney disease c osteoporosis which of these diseases has lower rates among people living 1500 meters above sea level? A diabetes b chronic kidney disease c osteoporosis. Have a think and I'll be back with the answer soon. You're listening to unexpected elements from the BBC World Service. This week we've been inspired by the antics of slacklining athlete Jan Rus. But as a species, our ability to navigate a piece of rope is, let's face it, on average, pretty poor, especially when you look across some other animals on this planet. I met some incredibly impressive athletes this weekend as I moved into my new house and my new back garden has a flurry of squirrels that ran rings around me without even touching the

15:42ground thanks to their abilities to climb creepers. So how do they do what they do so well and what can we learn from them? Hit tell us more about these acrobatic rodents is Lucia Jacobs, emerita professor of psychology and cognitive biology at the University of California Berkeley. Hello, Lucia. Glad to be here. I mean, how long have you been studying the lives of squirrels and why squirrels? Since 1981, it was really because they were a very understudied species at the time and I was interested in the question of whether or not they remembered where they buried their nuts. I think I was really fascinated by all their decisions around harvesting nuts and catching them and then later I got very interested in how they move and jump and things like that. I mean, and they are so fast. They're incredibly graceful with it and I think I probably see a squirrel every day, but I don't think I can say much about them. Can you give us a squirrel 101?

16:48I mean, they're basically monkeys. Both are diurnal. They live in trees. They eat nuts and seeds. They're long live, large-brained, interesting animals around different continents. There aren't that many species, but the ones that there are are very successful, particularly the eastern gray squirrel, which is the squirrel that's native to the east coast of the United States, but it's been introduced to England and Europe and South Africa and all over. It's very, it's a very smart and successful squirrel. I was wondering whether they have distinct personalities. It's a great question because there is a enormous amount of research right now on squirrel personality and we're finding that across species, there are really distinct personalities that are you see as in humans, they're kind of lifelong. I've worked with wildlife rescue to study the ontogeny of the development of cognition in baby squirrels and my impression from doing this and

17:50you can see a personality difference before their eyes are open, the aggressive ones would be much more likely to explore to the end of the tree than the dossal ones. There are some that were very tentative and that's been shown in lots of studies and birds. There's kind of slow thinkers and fast thinkers and the slow ones, they don't necessarily do words, they do better in some context. I want to ask you about their tree-based gymnastics. What makes them so good at spending time in the trees? What kind of physical adaptations have they got? They have four fingers that have big claws that grasp a branch and then the fifth one, their thumb is an it's actually a thumb with a nail and they use that to hold enough. So they've got a very specialized front paw that does two things. It grabs a branch and it holds enough. What squirrels are doing when they leap on their front paws is that they basically hit the branch in a handstand and they control the stiffness of their front legs because sometimes

18:53they're going too fast and they're going to overshoot. Sometimes they're not going fast enough and they're going to undershoot and so that what they want to do is stick the leap and to do that we show that by stiffening they prevented the overshooting and by loosening the leg they could prevent the undershooting and then just in limb and Ron fearing in his group on robotic's, they took that insight and built a one-legged robot that could leap and land without a brain leap and land on on a very narrow rod. So this is your robot version of a squirrel? That's right, that's right. We actually started a consortium group of biomechanicist neuroscientists, me as a squirrel by behaviorist to see what can squirrels teach robots basically? How they use their front paws was a big breakthrough. Is there anything from that robot squirrel that is going to be used in robots? Are we going to see squirrel-type robotics in the future? Well, you know, Justin got a grant from NASA to build his

19:58Salto robot to explore the surface of the planet Saturn. So yes, squirrels into space. Robot squirrels in space. This is where I want every interview to go. Yes, of course. Hi, Lucia, I have a question. Basically, this Northland flying squirrel that I used to see in documentaries when I was growing up and it sort of reminded me, I don't know if you know the late evil can evil because I used to watch him here as well. And the way it jumps just reminded me of him, but you know, if I was to ask this, where does that squirrel get the guts to jump at that high level from three to three? Is there something in its mind that is a bit different from other squirrels that gives it that courage? You know, I think it's it is courage and it's something that squirrels have to learn and they actually in the forest, they have certain roots they take. So they learn certain roots. They're kind of like rock climbers. You know, this is an easy route. This is a

21:01hard route. And if you're not sure, you'll take the easy route. What they do is they will you'll see them head bobbing, which is a way of estimating distance. And squirrels actually have a very special brain for that. They've got a part of the brain's superior cliculus, which is 10 times bigger than that of a rat. And we saw in the experiments that squirrels, when you give them a bouncy branch, they change their whole approach. They don't jump from the end. They jump from the middle. You know, they change the force, all that. So they basically, that's what they do from the time they're eight weeks old. Before we let you go, I just want to know, how do they remember where they buried or not? Well, again, they've got really good memory. What we've actually shown is in Pennsylvania, wild squirrels, the brain actually in an adult is bigger in October than it is in June or January. And that's very unusual because most small mammals have big brains in the summer when

22:01they're breeding and small brains in the rest of the year and the squirrels, the opposite. And we also showed on campus that we gave them memory task where there were like four objects on a table and they had to remember where was the nut. And we found that how they encoded the location was different in the fall than it was in the spring and the summer. You know, they're making thousands of caches and their brains are getting bigger. They're thinking differently. They're encoding space differently. Every time they come on a nut, it's like, do I eat it? Do I save it? And so we've studied that decision and what they do actually is they pick up the nut. They roll it in their paws and they very specialized paws for this. What it's doing is actually weighing the nut. A heavier nut is more valuable and the more valuable means it's more worth investing more so it's not going to be stolen. They're caching thousands of nuts every fall and the only way they're going to beat the competition is by remembering where they are. We also found that they cache in according to the

23:07species. So they'll put the almonds in one corner and the hazelnuts in another. That is absolutely fascinating. Unfortunately, we're out of time, but Lucia, I'm so pleased though that we had time to to talk about that as well as what makes a squirrel such a good athlete. Lucia, Jacob, thank you so much for coming on to unexpected elements. Great, thank you. Okay, bye-bye. I will never look at a squirrel in quite the same annoyed tone. So, high-wire antics in South Korea took us to risk taking behaviors and how to spot them in the brain, how to handle a high rise and the delightful surprises of squirrel science. Still to come on the show, we've heard about Yen Roo's teaturing along a slackline, 120 meters up in the air, but what else can be found up above our heads? Stay tuned to find out.

24:10Fall tastes better with better ingredients from whole foods market. No added growth hormones are antibiotics in their meat department. Means slow-bray short ribs are even more satisfying. All seafood is well caught like their vibrant sockeye salmon or verified responsibly farmed, and all sweets including fall-themed cookies are made without high-fructose corn syrup. Spice up fall at Whole Foods Market. You so-ca-honda dealers are honored to help the community. Our program started the first deaf and hard of hearing football team of its kind in our league. The helpful so-ca-honda dealer surprised us with brand new uniforms and giving our athletes more than just jerseys, a community investing in their program. And we want to help you too, with 1.99% APR on a 2026 Rigline for well-qualified buyers. At your so-ca-honda dealers, make their contract limited by finance through Honda Financial Services, not all buyers will qualify to take delivery by 11-226. This is Unexpected Elements from the BBC World Service. I'm Marnie Chesterton in Cardiff

25:21in the UK and I'm here with Andradefiskotan in Booker Estrumania and Mykoko Loki in Nairobi Kenya. Loki Dake. So we are a science show inspired by the news headlines. And this week we couldn't tear ourselves away from the sight of the slacklining world champion Jan Rousse balanced 120 metres above the streets of Seoul performing high-wire tricks. We've now reached the part of the program where one of our panelists brings along a story that perhaps has gone under the radar of global news and maybe it deserves a bit of time in the world service spotlight. As ever, completely meaningless points are awarded if you can somehow link it to today's theme. Any volunteers? Yeah, we've been talking about slacklining and acrobatics today and they found a story about a community here in Kenya and their athletic abilities. Oh excellent points awarded Michael, well done. Tell us more. Thank you for the points, Marnie. Well, I came across a study published earlier this year in

26:24the journal Nature that compared the vertical jump performance of the Masai, track and field athletes and non-athletes. Now the study mentions that the Masai, who are a community found both in Kenyans and here, have a traditional jumping ritual performed by young warriors. These jumps and repetitive hops, as I have personally witnessed in Kenya are also performed as part of a Masai traditional dance. So this study compared different types of jumps and repetitive hops among Masai community members, Slovenian high-jump athletes and sprinters and Slovenian non-athletes. The participants were male aged between 16 to 35 years old. Okay, Michael, can I just check because I've seen a dance that a Masai group of women did to welcome me to their community and it did involve some hops but it was mainly singing. I'm assuming that this was more hop and less music. Well, I think it depends with

27:26the kind of dance they're undertaking, but a lot of the Masai dances that I've seen do include both singing and the jumping as well. Now it's likely that in the group you were in, maybe they were just doing something for you where you did not have to to jump as high-marnie probably the reason. Okay, yes, they were kind of indulging the idiot tourist that couldn't really join in. Tell me what the study found. Well, the study used an app to mention the heights of three types of jumps that is counter-movement jumps. Now that's where you do a rapid downward dip before exploding upwards, squat jumps where you start from a static squat position and jump upwards and repetitive hops. The athletes outperformed the Masai in the counter-movement and squat jumps, but in the repetitive hops they both achieved similar heights and significantly outperformed non-athletes. The Masai averaged height of 36.2 centimeters, the athletes 35.93 centimeters, and the non-athletes 20.98

28:31centimeters. Okay, and can I check in this group? Were they all roughly the same height? Because Masai quite tall, aren't they? Does that give them a head start? Well, actually there's no clear indication of the heights of all the participants, but presumably maybe they were or maybe they had varying heights actually. There was no clear indication of that. Okay, because that's quite a significant difference. So 36 centimeters versus non-athletes managing 20 centimeters. How high could you guys jump? What do you reckon, Andrada? I think they would fall into the non-athletes category. I might join you in the non-athletes category. I'm in the studio now and that's about 20 centimeters. I can do about 10. That's good enough. How'd you get a go-to? Yeah, I think I think I did about 10 as well. This is the BBC World Service. Welcome to Hopping

29:32on the radio. Okay, so Masai doing 36 centimeters is suddenly actually very impressive. How can they jump so high when doing repetitive hops? Well, money according to the research article, their findings concluded that the mass size cultural practices enhanced musculoskeletal adaptation from an early age. So they are also more consistent in their jumps, likely reflecting a long-term adaptation to hopping from a young age. Okay, so it's kind of just like many things like playing the piano. If you do it a lot, you get good at it. Andrada, my parents did not allow me to jump on the bed and to use the springs and now you've been through arguments. Your hopping career is nonexistent, Andrada. So dear parents, do allow your children to hop on the bed when they want to. And Michael, the community where you're from in Kenya also has a traditional dance that involves

30:34jumping and a load of acrobatics, right? Yes, Marney, this is the Canva community here in Kenya. And there's a dance style in the community, which was a commonly featured dance performance during the National Celebrations event decades ago. It involves a lot of jumping, summer solts, flips, cart wheels, tumbling passes and other acrobatics styles. Now, I have never danced it because it required real stamina and skill. But when I saw people performing the dance, what I found interesting was that included middle-aged people as well, both men and women who were able to execute those acrobatics seamlessly and almost effortlessly. It is one of those things. There are so many dances that I'm currently thinking about. And also things like, I don't know, ice skating that require particular movements from your body and it's and I think if you grow up with it, then you're fine. Andrada, is there a jumping, summer solt acrobatics, dancing style in Romania? Well, there is one. It's called Karushari

31:37and it's from my region and it's performed by men. Mostly, most of the acrobatics, and even involves throwing some sticks up in the air and hoping to catch them. Oh, we've got something similar in the UK. We've got Morris dancing, which is traditionally done by men. And in fact, historically, women weren't allowed to do it, which obviously means that now that there's kind of rebel groups of entirely female Morris dancers. But it does involve sticks and handkerchiefs and jumps and shinbells, which I think are going to be next season's trend. I think everyone's going to have them. Anyway, Michael, thank you so much for bringing Masai jumping skills as measured by science to our attention. Thank you, Marni. Listeners, if you'd like to get in touch about anything that you've heard us talking about on

32:38the show today, you can email unexpected at bbc.co.uk or you can WhatsApp, you can send us messages and voice notes to plus 444-330-678-3080. You can even write to us. I do love a postcard. Please send them to unexpected elements, bbc world service, Cardiff, CF-10-4GA in the UK. And we'd like to make space to read out some of our favourite messages that are in the inbox. We've got one here from Jay Thompson in South Carolina about a programme we made a couple of weeks ago where we discussed paradolia. I don't know Michael andrada if you're aware of that, it's where you see faces in inanimate objects. So buildings and cheese graters. Andrada, do you want to read this? Sure, they say I bought and drove Saturn vehicles, six of them because, well, they had a grill

33:43that looked like a friendly female face. When the company was bought up and changed design to a mean face, I quit buying them. I'm currently googling Saturn car grill. There's just something about where how the lights and the grill are arranged that make it look like it's smiling. I totally get why people would go for that. Now, last week we got a bit derailed shock horror that that does happen on this show. We're talking about dogs on public transports. Do you remember this, Andrada? I do as mentioning dogs in my part of the world, scene or photograph, writing the subway or the buses. And a couple of listeners emailed in to tell us about Eclipse, who is a black Labrador mix that was famous in Seattle for writing the buses. Now, according to B, Eclipse would normally take the bus with her owner to the local dog park a few times a week. And one day Eclipse's owner took

34:48too long smoking at the bus stop and missed the bus. Eclipse boarded the bus without his knowledge and was found at the dog park four stops away. After that, she'd make two or three solo trips to the park each week. And Paul tells us that Eclipse would ride looking out of the window and at the appropriate time, trot up, bang the door to be let out at the dog park, where she'd happily play until picked up by her owner. Now, I can never resist a dog story, so that is fantastic. I researched a bit more on Eclipse. It turns out she even became the brand ambassador for Seattle's public transport authority. Well done. It's not just dogs that travel on public transport. We've had an email from Kathy, who says, your story about dogs taking buses really had me laughing. It reminded me of this great version about birds taking trains in Sydney. And Kathy has sent us a link to a recent story on ABC

35:52News, which says that two minor birds catch the train from Linfield to Atomon every day and then travel back. So there are birds doing a commute in Sydney, which is impressive. Do you think they've know that it's the same thing as flying from A to B? Because if I could fly, I definitely wouldn't get the bus. Maybe they are wired to conserve energy, and this is a way of saving calories. Yeah, that's true. I mean, we've been talking about animals having different personalities when it comes to our squirrel expert earlier. But it's true with a lot of, I've heard this from a lot of zoologists, particularly like if they're tagging particular animals, some of them will roam for miles and some of them just don't move at all. Yeah, I remember going up to this place where they have elephant orphans. And I learned from the keepers as you're walking with them that they all have

36:54their different personalities. And just like people, they would tell me, so I think that some of them probably who are okay to walk, some of them will just want to take the bus. So yeah. This is the point where I should say that yes, we are a science show, but we are also a broad church and we love people's stories about animals on public transport. So if anyone has anything that they'd like to send in on that or any topic, we do read all your messages and sorry if we can't feature all of them in the program. The email address to send us your musings is unexpected. At bbc.co.uk Still to come, we get in a spin over spider silk and start living the high life. That's coming up after this. Ella here, back with the answer to the quiz. Earlier, I asked you which of these diseases has lower rates among people living 1,500 meters above sea level, A diabetes, B chronic kidney disease, C osteoporosis. And the answer is A diabetes. Diabetes is caused when there is too much sugar

38:01in your blood, dutrae problem with the hormone insulin, which allows your cells to take up glucose. Research from earlier this year suggests that red blood cells absorb much more glucose from the bloodstream when oxygen is scarce, so they effectively act as sugar sponges at higher altitudes and compensate for faulty insulin. It's unclear exactly why this happens, but it may be a side effect of red blood cells changing their metabolism so they can deliver oxygen more efficiently. Well done if you got that right. If not, better luck next time. As well as letters and emails, you not also send messages pleading with us to find answers to the science questions that keep you up at night. It's Ask the Unexpected Time.

39:01This week our question comes from an anonymous listener and Drauder, would you do the honors and read this? Sure, they say, I have a bed spider that I've named Stanley, who lives behind a shelf in my kitchen. Stanley resides in an elaborate web. When a fly is ensnared in the web, Stanley comes sprinting out across the web to grab it, then sprints back again. This cut me wondering why don't spiders get stuck in their own webs? Thank you. That is a great question and luckily we know entomologist Dr Tim Cockro and could ask him why Stanley doesn't get stuck in its own web. Spiders have a few mechanisms that lead to them being able to walk around in their web without getting stuck. The first point is that not all of the spiders web is sticky. So if you've watched a spider making its web, those beautiful all webs that are a bit like the spokes of a bicycle wheel

40:02with a structure and the spiral in the middle, the spider makes its web and makes this incredible structure first of all. And then the last thing that it does is it goes around again and it attaches an extra layer of sticky silk to the web. So most of the web itself is not sticky. And so the simplest way that a spider avoids getting stuck in its web is that it just knows where to walk. But it gets more complicated than that though, because if a spider had to rely on just walking on the right bits of its web, well then it would probably get tripped up every now and then. And so spiders have evolved a number of mechanisms so that if they do touch the sticky parts of their web, well they can avoid getting stuck. One of them is that spiders legs are covered in very fine and finally branched hairs. And so as a spider touches a sticky part of its web, it's not the entire leg that is touching the stickiness, it's just the tips of these hairs. And so a very small surface area, I mean that it's much less likely to get stuck. But there's some quite recent research that says that spiders also have another trick up their sleeve, which is that their legs are coated in a

41:06kind of non-stick surface, a bit like a non-stick frying pan, which means that if they do touch the sticky parts of their web, they can pull their legs away without it getting stuck. Scientists know that this is the case because they've done experiments with spiders where they washed off the non-stick coating and then all of a sudden the spiders legs start sticking to the sticky bits of the web. That is fantastic knowledge there from Tim. Amazing stuff. Andrada, Michael, how do you feel about living with spiders? For me, I find like for example when I go over to a rural home in Eastern Kenya, some of the spiders out there, I mean whoa, I think they have a role to play in nature. Let me let them be. I try my best. Andrada, do you take a similar approach of let them be, but let them be somewhere quite far away? Well, I think spiders in Romania are not as terrifying as the ones Michael mentioned, but I simply let them be. I don't know if anyone of you has seen the King

42:08Baboon spider. I mean, just the name itself. You're described to you are kind of spider, this is and this is spider that is found here in Kenya. So it's a tarantula. The ones I've seen I think on the ground are sort of orangy brownie in color. Yeah, they look like you need to leave them alone. I mean, it's kind of cute. It's like a Labrador. That's fluffy and it's the size of someone's palm. My sister had a specific scream before spider. So I knew when I was growing up, if my sister screamed a certain way, I knew there's a spider somewhere. That is useful non-language-based information. Thank you Michael and Andrada. And also thank you to our anonymous listener for the question and thank you Dr Tim Cockeroll for the answer. Each week I have the chance to add some science story to the week's theme with the help of the

43:10BBC's secret vault of past programs, which only very special people are allowed in. This time, I was hunting for science stories of life up up in the atmosphere. This show started with a tight rope walk or a slack rope walk, 120 metres above the busy streets of Seoul. That's one thing, but other animals can get higher no problemo. From our sister show Crowd Science, here's presenter Alex Lathbridge trying to work out with Dr Jason Chapman, how high an insect can fly. Okay so how high are all those insects flying? The majority of those insects are concentrated between about 100 metres and about 6 or 7, maybe 800 metres. So pretty high. We do see small numbers going a little bit higher than this and we can see them up to about 1.5 kilometres above the ground, but that's quite small numbers. So that's most insects. The bulk of which you can find

44:12higher than our Highline Daredevil Jan Roos, but lower far lower than an aeroplane. Now Alex Lathbridge was back with another Crowd Science looking at how high birds fly. From it, in a pleasing case of double nominative determinism, here's Dr Lucy Hawkes from Exeter University talking about climate and biologist Larry Swan struggling to the summit of a remote mountain in the Himalayas when a bird shaped surprise joined him. And he described how he was listening to the usual silence at those altitudes, but he says a sound came a quiet hum muffled by distance and suddenly I knew I'd heard it before coming from the stars above me, I heard the fulking of bar-headed geese and he stands there amazed about seeing these geese flying directly over the summit of the fifth highest mountain on earth, Mount Maccalaue. It was as if they were ignoring the normal rules of physiology and define the impossibility of respiration at that height

45:15by wasting their breath with honking conversation. When you're one of these first people that's ever been to these incredible altitudes and to be there to struggle so hard to be there, to have so much equipment and then just to see some geese to have them kind of like just just just chomping on past you, you must be like what am I seeing? Must be extraordinary. And so it kind of put them in the Guinness Book of Records between his observation and also another climber called George Lowe who'd seen bar-headed geese flying over the summit of Everest. They just kind of entered into the Guinness Book of Records there and sat there for many many decades as the world's highest flying bird. So I should say that that record has been swiped by a vulture, the Rupel's vulture, in a rather unpleasant way which, sorry I'm going to share with you, it collided with an aircraft over Ivory Coast in 1973 and the plane was fine,

46:20but the endangered vulture was very much not fine and after picking the bits out of the aeroplane they identified what species it was and worked out that it had been flying to collide with the aeroplane at 37,000 feet so that's nearly 11,300 meters and so that's why the Rupel's vulture has the world record. Now we are still talking about the first layer of the atmosphere here, the troposphere and that's where almost all the animals, the weather, the water mass, the air mass, it all lives there, it's a busy place, but let's carry on going upwards, past the stratosphere in its ozone layer, past the mesosphere which is where meteors burn up and you get to a part of the thermosphere called the ionosphere and solar physicists once described the ionosphere as the ignoresphere because they know so little about it and from 2018

47:26here's an episode of science in action with host Roland P's talking to meteorologist Chris Scott about this ignoresphere. The ionosphere is the electrified part of the Earth's upper atmosphere so it extends from about 60 miles upwards out into space and it's generated when sunlight stream ultraviolet and x-ray radiation from the sun is absorbed by our atmosphere and it electrifies the gases there. And I remember when I first listened to the world service in remote parts of the world, I'd hear this sort of crackly sound and it was fading and horrible but I was hearing it thanks to the ionosphere. Yes, so the ionosphere was used to transmit radio signals around the world and the reason for that is that the characteristics of this electrified layer are such that they reflect shortwave radio so we would use the ionosphere to bounce these signals over the horizon and to the locations much further away and the reason that would fade in an out and crackle and whistle is that the ionosphere isn't a perfect mirror there will be waves rippling through it and as we've discovered there are disturbances within it and those would

48:29cause the signal to be affected in some way. So that was a little clip about the ionosphere but I said I was searching for life up in the atmosphere and the ignoresphere is where many of our satellites and the International Space Station live so this is where I've found my highest flying insect in the fruit fly lab of the ISS. My name is Charmila and Patacharya, I'm the program scientist for space biology at NASA headquarters and I have been helping send fruit flies to space. Flies actually have a genetic makeup that's similar to humans and other mammalian systems so measuring the changes that we see in terms of behavior, changes in muscle function, changes in heart function when you're limited for space, when you're limited for mass of how much material you can send to space, organisms like the fruit fly turn out to be extremely valuable

49:33for doing our research. I should say that that clip was also from the same crowd science we heard first which is how high can insects fly. Am I cheating? Does that count if you get a fly on the International Space Station? Does that count as high flying flights? I think it goes both ways because well you were taken there not with your own flight strength but on the other hand you are there. If you do end up as a human on Mars you are on Mars, you are out on Mars even if you didn't walk there. So I think the same for fruit flies, yes we should give them that credit. And ultimately, Monty isn't the International Space Station just a big bus that's traveling fast if we care about dogs traveling by bus or by train then I think fruit flies they should count brilliance. Okay so what have we learnt over the course of the show? Well we've looked into high rise buildings

50:37and how they stay up. We've delved into the brains of folks that like doing dangerous stuff to find out why. We've marveled at the mass size athletic abilities and spiders amazing talents for not getting stuck in the high lines they've spun themselves. But it's high time we left. We've come to the end of the show. I should thank this week's panel. In Bucharest Romania and rather Fiskatown thank you so much. Multimersmarni and in Nairobi Kenya, Michael Kaloke. It's been a pleasure thank you. Hi five everyone. Quaheri. Hi five soul rounds. I'm Monty Chesterton. The producer was Alice Lipscomb Southwell with Ella Hubba and Robbie Voicahoski. Do join us next week. They'll probably be more unexpected elements. Part of why I blew the whistle was I didn't want to lay in bed in 20 years having seen another

51:46million people die and know that I could have done something when I had a chance. This week on the interface we're talking to Frances Haligan. The Facebook whistle blower who leaked the documents that changed how the world saw social media. And now she is the subject of Aaron Sorkin's latest movie The Social Reckoning. So join me, Thomas Dermain. And me, Jess Maddox, for the interface. Listen on BBC.com or wherever you get your podcasts.