SciShow Tangents - Rivers

Episode Date: April 7, 2020

It's Spring here in the Northern Hemisphere, and the rivers swell with crystal clear snowmelt from tall mountain peaks... and we're all stuck inside and can't really look at it! Dang it! So I guess close your eyes and imagine floating down a beautiful river with your favorite podcast hosts as they drone on and on about bridges and salmon and stuff.  Again, a big thanks for choosing us as the thing to spend your time with! Be well, everyone! Follow us on Twitter @SciShowTangents, where we’ll tweet out topics for upcoming episodes and you can ask the science couch questions! While you're at it, check out the Tangents crew on Twitter: Stefan: @itsmestefanchin Ceri: @ceriley Sam: @slamschultz Hank: @hankgreenIf you want to learn more about any of our main topics, check out these links![Truth or Fail]Kiteshttp://www.kitehistory.com/Miscellaneous/Homan_Walsh.htmhttps://www.uu.edu/dept/physics/scienceguys/2004Apr.cfmhttps://books.google.com/books/about/The_Kite_that_Bridged_Two_Nations.html?id=7tukmQEACAAJStone-carvinghttps://www.asce.org/project/five-stone-arch-bridges/Explosionshttp://www.bbc.com/travel/sponsored/story/20160815-the-buddha-that-calmed-the-seashttps://www.theatlantic.com/culture/archive/2011/02/why-is-ottawa-blowing-up-its-river/338889/https://www.nap.edu/read/6289/chapter/3#16[Fact Off]Salmon & sea lionshttps://wildlife.org/sea-lions-to-be-culled-to-protect-salmon/https://www.oregonlive.com/pacific-northwest-news/2018/03/battle_of_species_pits_protect.htmlhttps://www.theatlantic.com/science/archive/2019/01/killing-sea-lions-save-salmon/581740/https://www.fisheries.noaa.gov/west-coast/endangered-species-conservation/adult-upstream-passage-west-coasthttps://oceanservice.noaa.gov/facts/fish-ladder.htmlWildebeest boneshttps://www.pnas.org/content/114/29/7647https://www.frontiersin.org/articles/10.3389/fevo.2020.00031/full#h6https://www.sciencedirect.com/science/article/abs/pii/S2352249618300429?via%3Dihubhttps://news.uga.edu/animal-carcasses-source-river-nutrients/[Ask the Science Couch]Rivers on Titanhttps://www.nasa.gov/feature/the-mysterious-lakes-on-saturns-moon-titanhttps://www.nasa.gov/feature/jpl/cassini-explores-a-methane-sea-on-titanhttps://www.space.com/36904-titan-evolution-more-like-mars-than-earth.html[Butt One More Thing]The Great Stinkhttp://www.bbc.co.uk/history/trail/victorian_britain/social_conditions/victorian_urban_planning_04.shtmlhttps://www.open.edu/openlearn/science-maths-technology/engineering-technology/how-london-got-its-victorian-sewers 

Hello and welcome to SciShow Tangents, the lightly competitive knowledge showcase starring some of the geniuses that make the YouTube series SciShow happen. This week, as always, I'm joined by Stephan Chen. Hello. Stephan, what's your tagline? Recently into tea. Sam Schultz is here with us as well. And what's your tagline?

Drinking water. And Sari, what about you? What's your tagline? Butter beans. And I'm Hank Green. And my tagline is, there is a frog in my hat. Every week here on SciShow Tangents, we get together to try to one-up amaze and delight each other with science facts. We're playing for glory, and we're also keeping score and awarding Sam bucks from week to week.

We do everything we can to stay on topic, but we won't be great at that. So if the rest of the team deems the tangent unworthy, we'll force you to give up one of your Sam bucks. So tangent with care. Now, as always, we introduce this week's topic with the traditional science poem this week. It's from Sam. A run, a crick, a brook, a stream, all names we call a river.

And since they are this week's theme, some facts about them I'll deliver. One thing is they use gravity to flow from mountains to the sea. Their churning waters generate energy that we can aggregate. They bring us water for our grain, provide a home for frog and crane.

Why, with patience and a little time, a mighty canyon they can grind. And if a river you live near, you can float on it and drink a beer. So thank you, rivers everywhere, from Amazon to Nile for flowing forth from here to there in a calm, meandering

style. Not always. Shut up, Stefan. It rhymes with Nile, okay? And it's the right syllables. The thing that I now have a question about is can you socially distance while tubing?

Because I feel like I'm going to need to. I guess if you tie your rafts together with rigid six-foot poles. Yeah. Uh-huh. Yeah. And then it's like, throw me a beer. And you're like, no. That's not allowed. You need to bring your own beers.

So, Sari, what is a river? I tried to look it up. This is a geography question. What I could tell is a river is moving water. But like a bunch. But like a bunch. So a stream can feed into a river. Tributaries can feed into a river.

But not too much water because if it's moving water, that's just the emptying part of the river, then it becomes the ocean or a sea. Are you telling me that the sea is kind of the river? But doesn't it hit the point then that it's not flowing into anything? Is flowing into something the important part of being a river? Well, no, because rivers can flow both ways. You can have a tidal portion of a river where you're close enough to the the sea that actually when the tide is coming in, the river kind of flows backwards. So the most important thing is separating rivers from lakes, I think, because they're similar-ish size bodies of water or can be. But a lake is much more still than a river, which is constantly flowing.

And that means different ecosystems can live in both of them. constantly flowing and that means different ecosystems can live in both of them so it's easier for life to grow in a lake while the water is more still because they can take root places and don't get swept along by a current but a river that current is a big factor in the biology and ecology of the system do you know the etymology of river sari it's very boring all i could find was that we've been calling rivers, rivers for a while. So in vulgar Latin, it was riparia, which meant riverbank or seashore or river. So anything like where there is water and also land. And the old English word was, I don't know how to say this because it's the letter E, the letter A.

Ia, meaning river, which was similar to Latin aqua. So just like water in general. It was just the letter E and the letter A. Yes. Okay. My guess would be that river and water were two of the first words. Yeah. Like we had those ones early, just for direction, for wayfinding,

for like place description description and also water. It just comes in handy. Like you need it a lot every day. So it's probably not interesting because we've all we've had these words for a long time since before we can remember, really. And that brings us to where one of our panelists has prepared three science facts for our education and enjoyment. But only one of those facts is real.

And the rest of us have to figure out either by deduction or wild guess which is the true fact. Sari is going to present these facts to us, and if you fool us, you will get a sandbuck for each one you fool, and if we get it right, we will get the sandbuck. Sari, what are your facts? The Niagara River was hard to cross by ferry since the currents were so rocky. And it would have made things a lot easier to build a bridge between the U.S. and Canada to help with tourism and other kinds of traveling. And in 1847, an engineer named Charles Ellett Jr. was awarded the contract to construct a bridge across the Niagara Gorge above a spot called the Whirlpool Rapids. It was too dangerous for boat travel in that spot, but it was the narrowest part of the river.

And because it was such a challenge, Charles rallied the local communities to help. So which of these three things is true? Number one, he created a kite flying contest and offered a prize to the first kid who could fly their kite from one bank to another. Then he used that kite string to pull across increasingly bigger ropes

and start constructing a suspension bridge. I'm going to be mad if that's not real. Number two. He created an artist's festival in a quarry near the river, inviting sculptors to create large, specifically carved stones, which they could add personal touches to, that locked together like puzzle pieces to make a stone bridge strong enough to resist the currents. Or, number three, he invited chemists and engineers to test out explosives,

because the rocks that fell into the river altered the currents enough to break up the rapids so that it was possible to navigate ships and build a timber bridge. One of these explosive experiments resulted in a mixture of black powder and a liquid chemical fuel that was the best explosive on the market until dynamite happened in 1867. So we've got three facts here. One of them is true. Two of them are fake. The first one, he did a kite flying contest and then used the kite string to draw across subsequently larger ropes

until they could build a suspension bridge. Number two, he created a temporary quarry and an artist's festival to have artists come and carve really good large bricks. Or number three, he invited chemists and engineers to test out explosives so he could get big hunks of rock into the river to slow down the current enough to build a timber bridge. I want to go straight to the artist's quarry did they so they got to do they get to like carve things that they wanted and would they like get a prize if they did something prettier than

other people he did have cash prizes to award which at the time were like five or ten us dollars but i think the the main marketing behind this sort of thing was come to the quarry. I have designs for rocks and I need them carved in a particular shape but within that you can add your own signature to it or you can carve in designs and like make a mark on this project and on this bridge that's uniting our two countries.

That's like working for exposure though. It totally is. Well, it's more like working for impact. Like I'm going to have a legacy. I guess. People find value different ways, though. It totally is! Well, it's more like working for impact. Like, I'm going to have a legacy. People find value different ways, Sam. Walking across this bridge might see my special rock if I get a handrail piece.

Some of those rocks are going to be under the water. Those artists got shafted. I like these all so much. The first one I loved the most, though. Yeah. That's the kind of thing that sounds just crazy enough to work that somebody back then would have thought of it, I think.

And you couldn't get it across some other way because the rapids were so bad. Right. But couldn't you go up with your big rope and cross it up? I mean, maybe not. A bunch of trees and stuff in the way. Is it maybe a very, very big river?

Was that said how big it is? I think the gorge is 800 feet wide and 200 feet deep. Okay, so that's totally doable to get a kite across that, depending on which way the wind is blowing. And was it the American kids who did it, or did the Canadian kids do it? I think it was, again, anyone who wants to can try and fly a kite. Anyone was invited. But which kid did it?

I want to know it was an American. I don't picture Canadian kids as big kite flyers. It's either not enough wind or way too much wind. The kite thing reminds me of spiders because I know there's some spiders that throw their web. They like live on one side of a river and they like poop their web

out into the air and the wind carries it across and then it gets stuck on the other side and then they can build a web off of that. Sari's face looks very disgusted right now. Did I just discover it? No, you can't look at my face, Facebomb, and use that

to guess. And then the last one just seems too smart for its own good. I don't even understand what you're talking about. They were like, come try out your blowups. Yeah. Blow up the cliffs, make the rocks fall into the river to disrupt the whirlpools. That doesn't sound ecologically sound to me. It was the 1800s, you know?

Oh, yeah. They didn't have ecology back then. That word literally didn't exist. So what year was this? He got the grant in 1847 and he built the bridge in 1848 or starting in 1848, I think. Wow. So in any one of these cases, he was extremely ingenious in his ideas for how to get this project started. And I like to think that he was like, here's what I'm going to do. And the people were like, oh, yeah, that's great. Here's the money. You can do it. My sense is that he was one of

the only people who really wanted to do this. A lot of engineers were like, no, this is impossible. You're asking for the impossible. And then Charles Ellett Jr. was like, give me the contract. I have ideas. I'm going to go with kite flying, you guys. Even if it's not real, it is so good. I want to hear about the ways in which it is real, which I'm sure is something. I feel like the kite flying must be the spider thing. And I just don't

think the artist's thing would work. It sounds like he would take, I don't know. It just doesn't sound right to me. How many stone carvers are there out there? Yeah, that too. In that specific area of the world back then? Maybe there were a lot. I guess that's what they were building houses out of.

Yeah, back then, masons were, like, everybody was a mason. Like, that was one of the only jobs. Well, then, never mind. I'm going to go with that one. As an artist, I have to have solidarity with that. Oh, no. Okay. With all the people working for exposure.

With hypothetical artists. Oh, shoot. I was going to go with number two, too. But do we want to double up? Okay, I'm doing it. Number two. I like the idea of this one. Oh, okay.

Okay, the real one is kites. Yes! I was so nervous. You had a disgusted face on purpose. I actually don't know what my face looks like at any given time, so. Okay. That's good to know. Oh, I love it. Tell me more. It seemed like you knew a lot about this one. You gave you had too

many facts. I was trying not to know what you kept asking questions. And I was like, oh, I'm excited about this. I love it. So the competition was held in January 1848. And the child who first succeeded to span the gorge with his kite, which he named the Union, was an American named Homan Walsh. He sent his kite from the U.S. side to the Canadian side. I think that first time it crossed, his kite string broke because there was a sudden like pull of the line and it got caught on the rocks and it broke and so he was stuck on the canadian side for eight days while this happened this child i don't know if he went there with his family or how did he get

there did he fly on the kite they were all no he like sent the kite across and then right i don't know the the story does not have very many details. It's on a website, but also a children's book. And I couldn't access the full children's book to verify. But he sent his kite to the opposite bank and then ran upstream, took a ferry across to go collect his kite and make sure the string was taut. And then he found that it had snapped instead. So then he was stuck in Canada for eight days

and then was like, okay, I'm going to try it again. And then repaired his kite, the union, did not go with a new one. He like had his trusty kite and then flew the kite across again and then won. Was there a lot of other people trying to do this? I think so. I think it was promoted in local papers

or whatever new system they had at the time on both sides of just like, hey, kids, win five bucks, fly your kite across this river in the middle of winter. He really wanted that five bucks. He's still alive, I think. And he says it's like a very good memory of his the one time that he flew a kite across the river. And that's basically what they did is like they took his string and then they did a bigger rope, a bigger rope, eventually a steel rope. Wait, how is he still alive?

And that was the start of their suspension bridge. He's not still alive. How is he still alive? 1847? Oh, never mind. Yeah, that's true. That would be way too old. He discovered some elixir.

Yeah. He was still alive at some point and he said that it was important. Thanks for fact- me i had all my other facts ready but i was ready for this old man to be eternal he died in 1899 that was a while ago all right well i'm glad it was a big deal for him even if he didn't get to live forever uh do you have any realness to the concrete quarry arts festival no just that stone bridges existed at the time i was looking at other bridges that were built in

the 1800s and it seems like they were mostly stone like stone was the next big technology is putting pieces together without anything sticky sticky rock to put them together and some of those bridges are still standing today, but they're mostly over small rivers, but they could weather the currents a lot more than wood. And then there's a tiny bit of truth in the explosion story, kind of cobbled together between two separate things. The Lishan, I think, giant Buddha in China,

is a 230-foot-high statue. And when it was constructed, the currents below it were really, really rough. And I think they partially created this Buddha statue to, like, hope that ships would be able to take safe passage. But so much rock fell off that it actually made the currents safer. That's neat. It's also from Ottawa, Canada and other countries in wintertime have so much ice flow in their rivers that if it was allowed to continue building up, it would become dangerous for the people who live nearby the riverbanks. And so every winter they just bomb their rivers, dig trenches and put dynamite in them and blow it up to break up the ice because it won't melt fast enough naturally. We've just done a bad job with infrastructure and

just been like, I want to live close to the river. And then the river is like, no, no, no, that's not how nature works. You can say we've done a bad job, but like they solved the problem. Because then we're like, no, no, no, we've got bombs. You're not a problem. I can blow you up. Like, usually you can't blow up a weather. But in this case, you can. All right.

Next up, we're going to take a short break. And then it'll be time for the Fact Off. Welcome back, everybody. Sam Buck Total's series in the lead with two points with her devastating Stone Quarry deception. I have one point. Sam has one point. And Stefan has nothing. And now it's time for Stefan to try and claw his way back with me in the back office.

We've got two panelists who are going to present facts to the others in an attempt to blow their minds. And the presentees each have a Sam Buck to award to the fact that they like the most. Who's going to go first? Well, it is the person who can tell me how long the third longest river in the world is, the Yangtze River. How long? Oh, this is devastating because being very wrong will just feel like, I'll be like, well, I didn't know how big Earth was, I guess.

I'm going to say 800 miles. I was going to say more than that. I'll say 1,200. Well, okay, Hank is closer. You both don't know how big Earth is. Okay. I was going to say more than that. I'll say 1,200. Well, okay. Hank is closer. But you both don't know how big Earth is. Oh. 3,917 miles. No way. Whoa.

How long is the Nile? It's 4,132 miles long. Oh my gosh. All right. So, Stefan, I guess I'll go first. So, rivers are great, and sometimes they kind of get in our way or we want to capture them in some way. Like, for example, maybe they're creating a bunch of ice jams and we got to blow them up. Or we just want to harness the energy of that river and build dams and stuff.

This is great if you want to store up a bunch of water and maybe get some electricity. It's bad if you want to store up a bunch of water and maybe get some electricity. It's bad if you want fish to survive. So we do want fish to survive. And in doing that, would you believe me if I told you that we created a delicious death trap for salmon to be consumed in a kind of sushi conveyor belt for sea lions. So fish ladders are a thing. And the idea of a fish ladder is like you have the dam and like that's like the water comes up to the dam and like obviously a fish can't get up. But then you can build sort of a thing that a fish can kind of swim up, a little external thing so the fish can continue on its path to its spawning ground and then things can get down and you sort of connect the two ecosystems that you've built a big wall between.

But at the Bonneville Dam in Oregon, sea lions started showing up in the 1990s. It started out with just like one or two and then a handful. But then they apparently started telling all their buddies about this amazing sushi conveyor belt. telling all their buddies about this amazing sushi conveyor belt and by the early 2000s there were like hundreds of sea lions showing up to just like grab the little fish out of the or just like wait at the top when they came out of the fish ladder and be like gulp thank you very much so uh the number of salmon actually decreased significantly as a result of this. And NOAA, the National Oceanic Atmospheric Administration, estimates that the sea lions eat around 10,000 adult spring Chinook salmon a year. At Willamette Falls, where the sea lions found another fish ladder to hunt at, there were an additional 25,000 steelheads migrating through that in the 1970s. And in 2018, they numbered in the hundreds.

So in response to this, wildlife managers have tried to scare the sea lions off. So sometimes they run at them and they're like, ah, that doesn't seem to work very well. They also have tried to blow them up. Not actually. They did, however, set firecrackers off to try and scare them away. That also did not work because the sea lions are like, have you seen all of these fish? They also tried trapping the sea lions, releasing them 500 miles away. And would you believe that the sea lions traveled

500 miles back so that they could eat at this fish buffet? They have had to start shooting the sea lions, you guys. Oh, no. We were like, we built a dam. That was really bad for the salmon.

And then we were like, well, let's build a fish ladder. And then it's like, well, the sea lions are really enjoying this fish ladder, so let's start to shoot the sea lions. The unintended consequences, man. It's hard. So sorry to end on a low note, but we are doing our best to protect salmon populations and hopefully we're doing something useful

with the sea lions after we shoot them. So they're still shooting them to this day? They are shooting them to this day. Oh dear. I imagine sea lion yelp was very wild when they discovered the salmon ladder. It was like, guys, I found the secret sushi spot.

Can you imagine sea lion yelp when they started to get shot? It's just like, guys, this restaurant sucks. The service gone really downhill here. This might be a foolish question, but how did they tell each other that all the salmon were there? Did they just all find it on their own? I do't know. I do not know.

I mean, like, I was wondering two things, and I did not find good information for either of these. Like, how did they find it in the first place? Because sometimes a salmon will jump out, and it will not get back into the ladder. And so you have the smell of, you know, dead and dying salmon, and that is a smell that might attract an animal from a long way away.

Yeah. Or maybe it was just accident. Then you have like, okay, like clearly it wasn't like one showed up and then two showed up and then three showed up. It was like one showed up and then two showed up and then four, eight, 16. Like it was clearly exponential.

Like they grew very fast. So like it does seem like in some way there was like family communication going on right like maybe this maybe the sea lions were just extremely successful and they were like well i'll just bring all of my offspring but i'm having no trouble creating because i get to eat 10 000 salmon a year are sea lions fairly social creatures i feel like you always see them clustered in big piles and pictures. That probably has something to do with it, too, where whether or not we've studied it, they might have some sort of communication of like, hey, there's food this way, as long as they're not in direct competition with each other. They have some sort of sociality. They have some communication. They have some communication. Stefan.

So in Africa, there's the Mara River, which I don't know what it ranks as as far as lengths of river. But around that river, there is, I think it's 1.2 or 1.3 million Serengeti wildebeest that make their migration through that area. And this is the largest remaining overland migration in the world. And so during that, they cross this river multiple times.

And at four of those crossing sites, overland migration in the world. And so during that, they cross this river multiple times. And at four of those crossing sites, I guess the conditions of the river end up being pretty bad at certain points, but they're wildebeest and they're kind of dumb and they don't really realize that. So they just keep trying to cross there. And that leads to a bunch of mass drownings happening. And so they're often migrating in like, they're not like one big herd of million. They're like packs of a hundred or several thousand. And like the entire pack will get consumed and drown in this river at these points. And so on average, this amounts to over 6,200 wildebeest deaths annually, which is very small compared to the overall size of the herd. So it doesn't actually affect them that much.

Unless you're one of the 62,000. 6,200, 6,200. But still, that's a lot of wildebeest. And so after this happens, obviously you have a bunch of vultures and crocodiles coming in to chow down. But a team of researchers wanted to see how these kinds of events were affecting the aquatic ecosystem because it's kind of similar to like a whale

fall in the ocean so like when whales die they end up falling to the ocean floor and then there's this like ecosystem that develops around its corpse for several decades as the corpse is consumed and so this is the same sort of thing happening in a river. And it's not a particularly large river. And in the paper, they did the math to compare to how many whales worth of biomass it is. And it's about 10 blue whales a year that is getting deposited in this river. The thing that I thought was the coolest was in the weeks after the events happened, 34% to 50% of the diets of fish in the river were wildebeest flesh. So even the fish are

getting in there and chowing down. And even four months later, wildebeest were still 7% to 24% of the fish's diet. So this is after the flesh disappeared disappeared but the fish were still eating the biofilms that were being supported by the bones and they point out that like these were probably way more common back in the day when there were many more large herds of animals roaming right right right like bison in north america and these are probably important or were important influxes of nutrients for the the river. And it's not a thing that I think we factor in when we're looking at like how we're modeling freshwater ecosystems or thinking about restoring ecosystems to how they used to be in nature.

We must let the wildebeests die. And also, I'm really happy that yours was kind of a downer too, Yeah. And and also I'm really happy that yours was kind of a downer, too, because I was worried that just by the fact of being about death, I was going to have less less good chance. But hey, it's the circle of life. Yes. All right, you guys. Time to pick your fact. Are you ready? Three, two, one. Oh, we split it. We split the difference, Stefan. I'm just happy I got one point. It was a good fact. I knew nothing about it. I've heard about hippo poop in those rivers, in the River Mara, but not wildebeest. I bet that's important.

There's a lot of hippo poop. A little too egg-heady for me. I just like the pure carnage of Hank. Now it's time for Ask the Science Couch. We've got a listener question for our couch-slash our couch slash blanket fort of finely honed scientific minds. This one is from at little Chris who asks, can rivers be made of another chemical? Can we have rivers of methane on other worlds? Not only can we, we do.

There is a methane cycle on, what is it, Titan? Titan, yeah. I figured you'd be able to answer most of this because it's a space question. And I think we've actually landed a probe on Titan. So we kind of got very briefly an up-close view of it. And it's kind of squishy there. You know, there's rivers, there's lakes, there's rain,

but it's all methane. And that's certainly not the only one. Like, anything that has, you know, fairly close together points for liquid and gas, those conditions, whether it's pressure or temperature, can be duplicated in other places. And you can have, you know, you can have diamond rain, you can have lead rain, you can have all kinds of, like, it just depends on the conditions of the individual planet we're talking about. So, yes, you can have hydrological-ish cycles of non-water chemicals. So, when people say diamond rain, it's actually, is it liquid diamonds that is raining?

It would, yeah. Well, no, it would be, I guess that would be like snow. Scrapple. But it would be like i guess that would be like snow but it would be like the carbon would be but it's still formed in a similar way to how yeah where it's like the planet is so hot that the carbon evaporates and then it falls down as like solid stones of diamond would be the idea we've never like observed this up close but it seems like it's what's happening like hank has been saying it all has to do with the temperature of the planet. So like on Titan, for example, the surface temperatures are really cold. So minus 180 degrees Celsius, which is minus 292 degrees Fahrenheit. And that allows for liquid methane

and ethane to be on the surface. And so, yeah, if it's hot enough, then things that on Earth seem like solid or impenetrable could be part of a cycle. Yeah, and this probably happens on Jupiter and Saturn, where carbon is evaporating from certain layers and then it is solidifying

and falling back down as diamonds. We can't go get those diamonds because they're deep, deep inside of a gravity well, inside of a very bad place, but they're there. I love the idea of geology on other worlds. You know, obviously, biology is cooler than geology in terms of complexity anyway. But I love that, yeah, there is really active geology on other places in our solar system and, of course, even more so in the rest of the galaxy.

It's kind of just boring here because we already seen all of it. Go other places, you see crazy stuff. Well, yeah, it's good to remember how really cool Earth is. Yeah. Like really exceptional and unique and like what? What? And also like three cheers for water. What a good substance.

I don't want to drink diamonds. That wouldn't do me any good. Yeah. For substances that we could have a cycle of, water, A plus. Good job, Earth. Drinking diamonds is only good for smuggling. Ooh. Yeah, that's true.

I feel like it would do a number on your intestines, though. Well, you you gotta package them in something squishy stuff i've got an idea give me your smuggling tips stephan i've gotta have another income source in this economy because i'm not going anywhere yeah like what is what is the illicit substance right now besides ourselves toilet paper you can't really eat that and it doesn't help. Yes, smuggling toilet paper inside of your body is counterproductive. All right, if you want to ask the Science Couch your questions,

you can follow us on Twitter at SciShow Tangents where we tweet out topics for upcoming episodes every week. Thank you to at Acrobat Eye, at Kenji Hawaii 5, and everybody else

who tweeted us your questions this episode. Sam Buck final scores. Sari and I tied for first. Sam and Stefan tied for second, or as they say, uh, last.

If you like this show and you want to help us out, it is easy to do that. First, you can leave us a review wherever you listen. That's super helpful. And it also lets us know what you like about the show. Second, you can tweet out your favorite moment from the episode.

And finally, if you want to show your love for SciShow Tangents just tell people about us oh boy that's so awkward maybe we need to figure out something else we did great if you want to listen to SciShow Tangents ad free

you can do that on Luminary thank you for joining us I have been Hank Green I've been Sari Riley I've been Stefan Chin and I've been Sam Schultz SciShow Tangents is a co-production of Complexly and the wonderful team at WNYC Studios. It's created by all of us and produced by Caitlin Hoffmeister and Sam Schultz, who also edits a lot of these episodes along with Hiroko Matsushima.

Our editorial assistant is Deboki Chakravarti. Our sound design is by Joseph Tuna-Medish. And we couldn't make any of this without our patrons on Patreon. Thank you. And remember, the mind is not a vessel to be filled, but a fire to be lighted. But one more thing. In summer of 1858, the banks of the Thames River in England smelled so bad of human poop from sewer runoff and flush toilets and amplified by the hot temperatures that they called it the Great Stink. Parliament members soaked their curtains in lime chloride, which is basically bleaching powder, to cover up the smell. But basically, it was so gross that it motivated them

to approve the engineering of a new sewer system that I believe folks had been asking for for a while. But because it was so stinky it got in Parliament, they were like,

oh, now it's a problem. A parable for our time. You got to impact the rich people first. Yeah, you got to get poop in their nostrils and then they'll fix things.