The CrowdScience quiz of the year

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1:26months, we're turning our final episode of 2025 into the CrowdScience Quiz of the Year.

1:37I am your game show host, Anand Jagatia, and here to play along in the studio are some fabulous minor celebrity guests. The CrowdScience presenter team. Hello team. Our first contestant has a magnetic personality and nerves of a carbon iron alloy. It is of of course, Caroline Steele. Woo-hoo! We're going to win. Also joining us is, these puns are going to get more tenuous as we go along, also joining us is someone with a brain full of so many golden nuggets of information, it's like a treasure chest. It could only be Marnie Treasure Chesterton. Yay! I'm here to pulverise you with my science knowledge.

2:17Our next guest is someone with a voice so rich it can transport you to other lands like a viaduct over the sea. Yes, you've guessed it. it's Alex Lathbridge. The voice can transport you because the crowd science budget isn't letting us. Finally, joining us down the line from a studio in Mumbai is someone in India whose programmes never fail to unlock new levels of understanding. It has to be Chavi Sachdev. Hi, Chavi. Hello. Barnacle. OK, without any further ado, let's get this quiz going. Woo!

2:55It's been a pretty epic year here on CrowdScience and all of us have been on some amazing adventures and made some incredible programmes along the way. And now we're going to test just how much attention you've all been paying to each other's programmes. And listeners, of course, we want you to play along at home. How much knowledge have you retained? Let us know what you scored at the end. So just one final thing before we begin. I wouldn't be a game show host without... We get a sparkly quiz show jacket uniform. That is so cool. You can hear the sequins. Shiny. It's giving 70s disco. So I'm wearing the quiz show jacket because I'm the quiz show host.

3:37But to make this fair, I'm not the only one who gets to wear it. So each of you is going to put this on and take a turn at being quiz master and ask the questions. Five presenters, five rounds, lots of sequins and lots of points up for grabs. Are we ready? Yes, I was born ready. For the first round, we need you to cast your minds back to April when me and producer Emily Bird tackled a question about why animals swallow stones and it led us on a quest into the gizzards of various birds. It also features a questioner called Robin and an expert called Oliver Wing from Bamberg in Germany. So here are three questions from that programme.

4:18Everyone ready? Yeah. Question one. What is the scientific term for a stone deliberately eaten by an animal? Alrighty. Alex looks like he knows. Question two. What is the most expensive thing ever found inside the gizzard of a bird? by the guy who we spoke to. Oh. Question three. What is the maximum weight of stones you might find inside an ostrich? How heavy is an ostrich? Ooh. Ostriches can be over 100 kilograms. We can't just be Googling stuff in the middle of the quiz, Caroline. Are you Googling? Cheating. No, no, no, no. I'm minusing a point. Caroline is on negative one. I was helping the team.

5:05I was looking up a tangential piece of information. Caroline. Has everybody got their answers down? Yeah. Okay, so in true quiz fashion, we're going to swap papers. So you take that one. Yep. Chav, you'll have to hold yours up to the screen. It's all wrong anyway, so there's no point. Time for the answers. And we're going to do it in clip form. So first off, here is a clip of producer Emily Bird talking to Dr Oliver Wings from the CrowdScience episode Why Do Animals Swallow Rocks? You know, there have been cases where even pressure stones Gems have been found in the stomach of birds, like diamonds.

5:41Really? Yeah. Wow. Rubies. I still think it's a very, very interesting thing. And, you know, every new stomach you open, you never know what you find. I found very weird objects. Like in one of the ostriches from South Africa, there was a pocket knife. No. With a small plate open. And it was obviously there for several weeks, I would say, because it was very strongly etched already. Oliver had them all organised in these little clear plastic boxes, kind of the size of a matchbox. And there were slightly bigger rocks from chickens. Oh, yeah, there's little white pieces. Yeah, the white pieces. And some pebbles from wild turkey-like animals called caper-caili.

6:24They kind of all look like maybe you'd find them at the bottom of a fish tank. But they can be really large. I thought I'd actually show you some of the biggest ones. Did you bring some back with you? Oliver is so kind. And he has loaned me a full set of bird gastroliths. Oh, I didn't know you were going to bring these in. That's so cool. These rocks. No way. Are from an ostrich. Oh, that's heavy. Okay. So it's like a Ziploc bag like you would put in your freezer for your leftovers. Yeah, so this is like a kilo of rocks nearly, I would say. Oliver has samples from 400 ostriches. what you're holding in your hand right now is one ostrich so these just came from one bird yeah this was everything that was in his gizzard yes you're right in saying that is about a kilo of rocks and it came from one stomach and oliver told me they can have up to three kilos of stones in so three times that and that's 50 50 did anyone get it i got four you got four oh nice still wrong As quiz master, I'm going to give Tabby half a point.

7:35Since we're being generous, Alex wrote Pocket Knife, which shows that he actually listened to the episode. I'm going to give Alex half a point. I want this quiz to be in the spirit of, you know, the festive season magnanimous points to all humankind. What if someone wrote Diamond Engagement Ring? Yeah, I can have a point for that. Who wrote that? Me? I bet if you found a diamond inside. Listen, Steele, you're already on very thin ice. Cheating earlier in class. So you're on minus half a point. Oh! You're on minus one now, you've got minus a half. OK, good job, everybody, for round one. Time to move to round two.

8:13And, Caroline, you are the quiz master. Woo-hoo! My turn for the jacket. Get the jacket. Get the jacket. Oh, that looks really good, Caroline. Caroline's rocking that jacket. Right. OK. I can hear the power in your voice. The power is there. Looking up tangential things is encouraged. Really? Maybe be minus points on this round. So in September, listener Lisa from Wales in the UK was inspired by our show on the longevity of dogs. Anand, I think you did that one, didn't you? That was about, why can't my dog live as long as me? Yeah. So Lisa listened to that and then wrote in with a question of her own about an animal and the laws of physics.

8:56Two of my favourite things. Get your pencils and pens ready. Here are your questions. which animal's acrobatic antics has been perplexing physicists for centuries next question which essential law of physics are these animals supposedly breaking or contradicting and that doesn't look great i don't think i don't actually know what the episode's even about i haven't been able to figure out from your clue well how the tables have turned finally our last question, slightly ethically dubious question. If you were going to throw this animal out of a building with multiple floors, which floor would it be most dangerous to throw the animal from?

9:42I know the answer to everything now. Really? Oh my gosh, amazing, Chavi. I'm impressed. Right, okay, so time for the answers. Swap your papers again, please. And then once you've done that, settle in for a clip of me talking to Greg Gaber, Professor of Physics and Optical Science at the University of North Carolina back in September. Let's hear that clip. The French physiologist Etienne Jules Meret took high-speed photographs to understand their motion. And how did the scientists do these experiments? Like, am I right in picturing people just literally dropping cats out of windows and taking photos.

10:25Yeah, fortunately they weren't really dropping them out of windows, but they were dropping them and taking photos. So Mary was just dropping them from like about a six foot height and recording them. Scientists had discovered the idea of angular momentum only about 30 years or so earlier. And angular momentum is sort of a conservation of twisting, really. The idea that if something twists clockwise, something else has to twist counterclockwise. So kind of how if you're sitting on a spinny office chair and move your arms to the left, the chair spins to the right. But the way the cats twist in the air to land on their feet left scientists thinking that something didn't add up.

11:11Scientists got this view of angular momentum that if you're in free fall and there's nothing to twist against, there's no way you could turn over because that would be a change of angular momentum. So they assumed that cats must be pushing off of something just at the moment they start to fall in order to get themselves starting to rotate. And are cats doing that? That may be a small thing they do, but it's not the main thing. A cat can use different parts of its body to twist and turn and bend to do that motion in order to land on their feet. So clever. So obviously this landing on your feet increases the chance of cats not being injured when falling.

11:57But you hear stories of cats falling out of 10-storey windows and being OK. And for me, the fact that they always land feet first doesn't really explain how they survive that sort of thing. And of course, Greg has looked into this. It's actually a little bit of a mystery that first came up in the 1980s because somebody actually started charting what sort of injuries cats got as a function of how high they fall out of windows. And they found that the injuries increase as the cats fall from higher heights up to about the eighth floor. And after that, the injuries seem to start going down dramatically, that cats falling from even higher heights will get fewer injuries.

12:42Yeah, and it's still a little bit of a mystery because thankfully nobody's throwing cats out of windows as controlled experiments, and I don't encourage anybody to do that. The best hypothesis is they realize they're in trouble, they tense up, and they're a little bit freaked out. but then they reach terminal velocity at about the seventh or eighth floor and then they feel their normal weight they have a good sense of what way is up and down and they're able to relax so a big hypothesis is just that when cats reach terminal velocity that is exactly the height at which the injuries seem to go down in the research that people have done

13:25Isn't that mind-blowing? The fact that you can drop cats from higher heights and they stand a better chance of surviving. I believe no cats were harmed in that research. So, answer's time. You ready? Question one. Which animal's acrobatic antics has been perplexing physicists for centuries? The answer is, of course, a cat. Who got that right? Yes, I did. Oh, everyone except me. Everyone except from Quizmaster himself. I would put bumblebee because there's this thing about bumblebee's flight is thought to be impossible because of aerodynamics. Interesting. OK. Well, no, sorry. Zero points, Anand.

14:03One point to everyone else. Question number two was what law of physics are these animals supposedly contradicting? I wrote conservation of motion. Oh, that is so close. Conservation of angular momentum. Anand wrote Nusen's third law. What did Xavi put? Gravity. Yeah, I put gravity Miley put gravity as well, which is a good guess So, Alex, for your conservation of motion I'm going to give you a third of a point I love that we've got into thirds Yeah, can we go into fifths and sevenths Okay, and our final question was The ethically dubious one According to science, which is the most dangerous flaw to throw one of these animals out of?

14:41Did anyone get this right? So the answer was eighth floor I put ninth, which is like the beginning of the curve going downwards. I thought Marnie should get half a point. What did you put, Chavi? I put second floor because I know higher is better. Okay, no points for you. Marnie, I'm going to give you half a point. Thank you. For ninth floor. Everyone else gets zero.

15:05That was a disappointing round for me. Caroline, thank you for taking a turn in the hot seat. It's now time to switch Quizmasters and Alex, you get to wear the jacket. I'm sad to give this up, but I've kept it warm for you, Alex. That looks good. The glamour. OK, everyone, it's time for round three. How is your astronomy? Poor. Sketchy. I'm an Aries. Please cut that. So for my round, you are going to have to cast your mind back to July when listener Dixon from Uganda asked us if we can harness the power of starlight for energy. So I headed to the University College London Observatory in North London in the UK in the middle of the night to meet astronomer professor Steve Fossey and take a look at the stars.

15:54So here are your round three questions. Question one. What is the unit that astronomers use to measure the brightness of a star? Oh man, I feel like I have that on the tip of my tongue. Question two. The brightness of all the stars in the sky is measured against one very special reference star called the standard star. But which star is it? I remember this episode and I feel like I should know the answers, but I don't. Final question. What is the brightest star in the night sky? Ooh. Good question. In the southern or the northern hemisphere? Wah, wah, wah, wah, wah. Write it down. He's quite mean.

16:40He is quite mean. And that was a great question. Look, to clarify, northern hemisphere. Okay, time for the answers. I need you to swap papers again. I'm so glad you guys can't see mine. Here is a clip of Steve Fosse blowing my mind in the UCL observatory as we gazed at the twinkling night sky. Well, when the clouds cleared up. So here we go. I think we're ready. Open observatory. The dome is opening very dramatically. It's like a single slice. is being pulled out very slowly. And we're seeing, ah, the night sky. So how do we measure the brightness of stars? Well, there's a system that we use using a peculiar unit called magnitudes.

17:33And these magnitudes are slightly weird because the scale is inverted, seems back to front. This goes back to antiquity when astronomers used to look at the sky and they would rank the stars. So they would say there is a star of the first magnitude, the first rank, if you like. There is a star of the second rank, which is fainter. And there is a star of the third rank and so on. But it meant that the brightest stars had numerically smaller magnitudes. So basically, all these astronomers are going, well, my star is better than your star. My star is number one. Yours is number two. Correct. Exactly right.

18:09One of the brightest stars in the northern summer sky is called Vega. and Vega is actually what we call a standard star but this is what we use as a reference star to measure brightnesses of other sources Vega is actually zeroth magnitude it's got magnitude zero my star is even better than number one star it's number zero it gets better because the brightest star in the sky is Sirius and Sirius is actually brighter than Vega and if you're brighter than Vega You go zero, where do you go? Well, you go negative. I'm leaving. Sirius is magnitude minus 1.4. Do you ever think that the astronomers are just, everyone sit down in the room and go, OK, we need to come up with a new system because my star is better than your star has made things very complicated.

19:04We're in negative numbers now. Your answers are the unit used to measure the brightness of the sky. is magnitudes. The reference star or standard star is Vega. And finally, the brightest star in the night sky in the Northern Hemisphere is Sirius or the Dog Star, which has a magnitude of minus 1.4. How did everyone do? Marnie got zero. OK, Chavi, how did you do? I got a one. I got Sirius. I got a point for the Dog Star Sirius. Marnie? Yeah, Caroline also got none. Me and Marnie got none. So there we go. The quiz is halfway through. How are you doing, listeners? Are you doing any better than a frankly quite terrible performance here in the studio?

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21:02This is CrowdScience from the BBC World Service. I am your very glamorous quiz show host, Anand Jagatir, and we also have the whole CrowdScience presenter team here playing along. We have Caroline. Hello! Javi. Hi! Marnie. Hi there! And Alex. Hello! And we're here to test our memories and your memories at home in the CrowdScience Quiz of the Year! Woohoo! Woohoo!

21:28So, three rounds down, two to go. But wait, what's that? A surprise klaxon? It could only mean the surprise quickfire bonus round. Classic! Yeah! Alex, give me the jacket. He was getting too comfortable in that. So I'm calling this round the things we do for science. And as you know, listening to this show, sometimes the job requires us to do some pretty extraordinary things. Sometimes fun, sometimes scary, sometimes downright undignified. So I'm going to play you five very quick clips and I want to know for a point each, who you're listening to and for a second point, what on earth is actually happening in this clip.

22:08There's 10 points up for grabs in this round. This is a big round. In total, large round. It's time to claw my way back from minus a half. Exactly, Caroline is all to play for. Everyone ready? Yeah. Okay, clip one. Oh, oh. Oh, oh, oh, oh. Oh, my back. Clip number two. Okay, she's flicking at me with her tail and passes by and laughing. Okay, clip number three. Bit more. More? They're crawling everywhere. Clip number four. Ah, f***!

22:48Whoa. And clip number five.

22:58I'm invisible. So remember we're looking for the name of the person who's in it and then what they were doing Number one, what was going on in that clip? I think I was sliding into a Northern Lights observatory because to get into the front door scientists basically get onto their bums and go down a snow slide because the snow has fallen so high that it's like the height of the observatory and you have to slide into the front door Was it fun? It was so fun It was also pitch black because the sun didn't rise It was one of those things where I look back and I'm like that was so strange but it was like a normal commute for everyone So I think that was what was going on.

23:31That is correct. Well done, Caroline. Marnie says Caroline was falling in a swamp. If only. Not a bad guess. Alex, what did you get? I did do that. I got Caroline falling. Not bad either. Another third of a point. So I knew that you were trying to view the northern lights and I put that you were like climbing up into the roof of an observatory. You get one point for Caroline and not a second point, no, because I wasn't climbing anywhere. I was sliding down. What, so falling gets something, but I don't get anything for putting snow and stuff? You put Caroline climbing through observatory to see northern lights.

24:05No, that's way more contextual. I'm just trying to get revenge. No, that's like correct. Can I have a sixth? You can also have a third. Thank you. Very generous of you. I'm moving on to the second one. Does anybody get this? I put Chavi with an ostrich. Ostrich? Good guess. I thought maybe an ostrich tail. I thought that you were being hit in the face by a cat. Cat. Yeah, I went cat too, but obviously that's, I don't remember you having done anything with cats. Okay, should I tell you the answer? Yes. You all got a point because it's me, but it was a cow. A cow tail. It actually says tail whipped by a cow while milking it.

24:44Yeah, I wasn't milking it, I have to say. She wouldn't let me get close enough. Yeah, fair enough. Yeah. Okay, we're going to do the next one. Who was this? Marnie. Alex and Marnie. It was Marnie and Alex. I only put Marnie. I only put Marnie too. I think maybe you'd get half a point if you only put one. So that is Marnie and I. We were letting ladybirds out in a studio. Anand put looking at bugs. I feel like that's not good enough, is it? I think that's half a point. Oh, yes. I think that's pretty good. Half a point. Thank you. Well done, everybody. That was a high-scoring round. Number four.

25:18Did anybody get this? I said Anand with a chainsaw. I thought it was Marnie with a motorcycle. I got Anand not complying to health and safety. I think Caroline is correct. Yeah, it was Anand being chased by a horrible man in a pig mask with a chainsaw. Oh, that was from the scary film. So Marnie put Anand being scared in the horror lab. Yeah, that counts. Marnie gets points for that. And then question five. I think I got this one correct. This was you, Alex. And did anybody get it? I said Alex with camouflage. Yeah, this was when you had to wear one of those. The invisibility suit thing. I'll let you have half for that.

25:56Half? Oh, mate, that is very harsh. Mean, mean, mean, mean, mean. Mean man. I've got the jacket on. I'm overriding Alex. Karen and I get to the point.