Eels Alive!

This is an iHeart podcast. Guaranteed human. Welcome to Stuff You Should Know, a production of iHeart Radio. Hey, and welcome to the podcast. I'm Josh, and there's Chuck and Jerry's here too. And this is Stuff You Should Know about eels. I know another podcast that has ruined something I like to eat, but now I can. What did it ruin? Or why? How? What part? How about this? When we get to the part where you're like, this ruined eel for me, shout. Scream at the top of your lungs. OK. OK. I want to give a hat tip to David Byrne via Yumi, who inspired this episode. The David Byrne? Yeah, The David Byrne. Yumi was watching David Byrne videos. He's on tour and I think she's going to see him. Yeah, it's a great show. Oh, have you seen it? Oh, yeah, I've seen the last couple of tours. It's great. Awesome. So he apparently was talking about a book he was reading about eels and how fascinating it was. No. That kicked off the idea for an episode on eels. Yeah, I went to read a new book. I just finished my book, Cameron Crowe's Memoir, which is fantastic. I'm sure. And by the way, I commented on his Instagram about what a great book it was and he started following me. No. Yeah. And I got to think that it was either an accident or maybe he like listens to stuff you should know. I don't see why he would randomly just be like, I'll follow anyone. He says they like my book. Right. So I don't know, Cameron Crowe, if you're listening, it's pretty exciting for us. Yeah, what up? Great book, though, his memoir. It's just it's almost too incredible to believe that that happened to him in his life. Is it called Recounting Crowe? Boy, no, it's called The Uncooled, but man, he've really missed an opportunity there. Yeah, I think more he dodged a bullet. Probably so. But I went to read a new book, Talking Heads. It was I had two books in my hand, The Talking Heads book and Abel Ferrara's memoir, The Filmmaker. And I went with the Abel Ferrara just because Bonnie Principally recommended it and it's shorter, but Talking Heads is up next. And that's it. I just watched Bad Lieutenant all the way through for the first time. This is a good movie. Buddy, what a film. I've got King of New York next. So are you on a kick now for him? A little bit, yeah. Where'd that come from? Bonnie Principally? Yeah. No, I don't remember. I think I just ran across Bad Lieutenant and I've known about it since I was a teenager and I've never really watched it. Oh, have you ever seen King of New York? No. Oh, dude, it's so good. Oh, good. I can't wait. Yeah, I mean, he's one of my favorite filmmakers. Great. Yeah, apparently there's lots of rumors that Harvey Keitel actually was on all the drugs he was supposed to be on on Bad Lieutenant. I'll let you know when I get to that chapter. And I saw someone say like, no, he actually wasn't. He's just that good of an actor. But that Abel Ferrara and the rest of the crew probably were on all those same drugs while they were shooting it. I know he was he was pretty into drugs. So I haven't, I've only a couple of chapters in so far, but it's really good. Okay. Well, when you get to the chapter called drugs, Colin, I love them. Let me know. All right. All that to say is that we're talking about eels and we'll get right into it. If you if you're an eel, if you want to claim to be an eel, you got to have certain qualifications. You can't just be like a sea snake or an electric eel, which isn't an eel, by the way. You have to be a member of the order and Gila forms or Anguiliformis. 20 families of eels, 111 genera, more than 800 species, ranging from just about four inches to those big old moray eels, sometimes up to 12 feet. Yeah. 12 foot long eel. That's just amazing. Yeah. The one thing that they all have in common is that they have long bodies that are typically worm like. They don't have pelvic fins, right? So, yeah, the ones that you would have developed, had you descended from water hippos, whales. A lot of them don't have pectoral fins. Some of them do have the dorsal fin on the back, but essentially they're just like worms or snakes like slithering through the water. And that actually is exactly what they're doing. They're slithering in a wave like motion. That's how they make their way. Because again, they don't really have fins. This to me is one of the facts of the podcast. Do you know what I'm talking about? Yeah, take it though. So eels can swim backward just by changing the direction of the wave. It's a reverse. And yes, they make a beeping sound when they do. Oh man. That's amazing. I mean, they got to let everyone know. It's like, I can't see where I'm going, everyone. Yeah. Eel coming through. Yeah. Also, I just want to take a second for a PSA. If you drive a truck that makes a beeping sound when it backs up, never ever just sit there idling with your gear in reverse. People do that. You're not allowed to do that. Yes. You mean I used to live next to a nursing home, I guess. And we lived on the side of their delivery area. And dudes would just do that. Just sit there with their truck in reverse, not moving. Yeah. Like six in the morning, I should say. No. All right. I agree. Eels have that smooth, slippery skin and it is coated in a slime. It's a protective slime. It helps them with their swimming. It makes them very streamlined. And it also helps regulate how much water is in their bodies, which is pretty unusual. And they're predatory. Like they're eating other fish basically while they're down there. Yeah, something else that's very neat about eels is that they don't like, they're not born little baby eels and then they grow up into big 12 foot long, 250 pound eels. They actually go through stages of metamorphosis like the butterfly does. Yeah. Like they don't look anything like an eel when they're born. And as they grow, they actually change shape and color in addition to size. They also very frequently will move from like the ocean to freshwater creeks far inland. Like there's a lot of great stuff that eels do that we just had overlooked for a very long time. Yeah. I mean, there's some fun, really fun stuff coming. They're basically solitary. I think there's a couple that we'll talk about later that hang out in the hundreds or thousands. But generally, like if you're a eel of size, you're going to be swimming around by yourself, backing up by yourself, beeping by yourself. They migrate and we'll talk more about how they spawn later because it was a bit of a mystery for a long, long time and still kind of is in some ways. Yeah. But they do migrate to a spawning area and they think they use the Earth's magnetic fields. They use a magnetite in their bodies to navigate. Yeah. And they're not the only animals that do. So we don't know for a fact. We just know that there is magnetite in their heads and that that is probably what's going on because it's so spectacular. The migrations that they undergo. That's essentially the only explanation we have on hand. That's right. If they are in tropical areas, warmer waters, where they migrate to spawn is probably near-ish. But if they're in the colder areas, it seems like they migrate to the warmer areas to spawn. So they may have to go a long way. Yeah. It's like how people in the Caribbean, they don't go on vacation because they live on vacation. That's right. And like you said, electric eels aren't eels and there's really not a whole lot else to say about electric eels, really. No. They're knife fish. They're closer to a catfish than an eel. Sure. So forget those guys. Pretty much. We really look too. We're like electric eels. We got to find out even though they're not eels, they got to be kind of interesting. Not really. So sorry, everybody. Yeah. But what is interesting is the moray eel. This is the sort of the most famous of the ocean dwelling eels, the saltwater eels. Member of the family, Muranide. 15 genera there, 200 species. It makes up about 25% of all the eels. And they live like, you know, if you've ever been snorkeling or scuba diving, you probably haven't seen one during the day. But if you've ever gone and put your face in a hidey hole in that coral, maybe you could see one because that's where they like to hide. Yes. Be careful though, because they probably will bite you if you stick your face in their hidey hole. Yeah. I did that a little bit in Belize. I was asked the snorkel fishing guys with this, they were spear fishing and stuff. And I was like, like with spear guns, I was like, can you teach me? They're like, come on, just follow along. And then, you know, he told me dive down there and put your face in that hole. Tell me what you see. Did he really? Yeah, yeah, it was cool. I was like, I was trying to do it like they did it, you know. Sure. But I didn't get anything. They did, but I didn't. Did you see any eel though? No, but it was a little scary to put your face down there, you know. Yeah. Yeah, I mean, doing that above ground can be pretty unnerving under the sea. That's just scary. Yeah, I felt like Timothy Dalton and Flash Gordon when he reached his hand into that thing. Or I guess Indiana Jones, didn't he do that in one of them? We had to stick his arm in his spiders everywhere. Yeah, they were insects. He had to stick his hand, I think, reaching for a lever or something. Yeah, so great. One of my favorites is the type of mooring. It's called a ribbon eel. Did you look pictures up of these guys? Oh yeah, they're gorgeous. Gorgeous. So they're very appropriately named. They're very flat and wide. They do look like ribbons, especially when they're undulating through the water. But one of the cool things is that they're born as males, blue and yellow males. And then all of a sudden they go, boop, I'm an all yellow female now. Yeah. Check me out. And they can reproduce either way, depending on what phase of life they're in. Yeah, they're just incredible. Very bright, almost fluorescent, like kind of one of those, you know, undersea colors that just don't feel like they should exist in nature, but it definitely exists in the ocean. Yeah, beautiful. All right, so there, if you know more, you know, they have a great smile. They're known for those really scary looking teeth. They have two sets of jaws. The second set, the pharyngeal jaw is faces backwards to kind of lock you in and keep you from escaping if they have you in their grasp. Yeah. But they're not, they don't have to. You don't need to be afraid of the mori eel. Like if they, if they get you in the water, it's probably because you're in there at night and it's obviously an accident. They're not like after people. Right. They only get you when you stick your face in their hidey hole. Yeah, I guess so. One of the reasons why people are like, man, those things look really aggressive is because they show their teeth a lot and that's not because they're trying to scare you or because they're really proud of their teeth. It's because they lack opercula, which are those plate like covers that go over fish gills. You know that they kind of go back and forth on. Yeah, they flabber. Remember like that money, Python sketch and what the meaning of life? Were there goldfish and they're moving their hands? They were simulating opercula. And one of the things opercula does is it regulates and kind of moves water over the gills. Well, the mores don't have that, so they have to get a lot of water through their mouth and then that's how they funnel the water through the gills. And of course, the gills is where the oxygen is absorbed out of the water into the circulation. Yeah, for sure. So that's when you're going to see the teeth. Like I said, you're not going to get bitten most likely, but if you do, it's not going to be fun for you. No. Those teeth are very sharp. It's a very painful bite apparently because it punctures very deep. So it could always get like tendons and nerves and stuff. And while they are not venomous, they do that slime. They have slime in their mouths as well. And it's a substance called hemagglutinin and it causes red blood cells to clump up. But they also, they think they generate something called a crinotoxin. So that destroys red blood cells. So all of that stuff is A, why it's painful and it can be like super prone to infection. You can, those teeth can break off in your wound. It's really not good. Yeah. I saw crinotoxins also are the reason catfish things hurt. Yeah. I feel like we talked about that in our noodling episode. That makes sense. Yeah. That's like sticking your face in a hidey hole, but using your arm instead of your face. That's right. So the moray is a type of ocean eel and you can kind of divide eels into ocean and freshwater, as we'll see. Although ocean eels are far and away the largest in number and type, right? Yeah. One of the other big, I guess ocean eels is called the conger from family Congreta. And they are like deep water dwellers like 3000 feet below the surface. Some of them hang out in some rocky areas like mores, maybe around coral reefs. But the thing that's remarkable about the European Congre is that that's the heaviest one, right? Yeah. They're not as long and slender as the moray. They're still long and snake like, but they're rounder. Like the biggest one recorded is 242 pounds, which is, you know, it's a game fish. So if you got a 242 pounder, that's a pretty good catch that day. Yeah. That was like how much a couch weighs. Yeah. Yeah. Oh, I'm so glad I said that because I've been forgetting just to mention this. So our dear awesome friend, Brandon Reed, right? He created, he's our webmaster, everybody. He runs and created stuff you should know.com. Yeah. And pal. Yes. And great, great pal. He created a website called Josh Clark Calculates. And you can go to JoshClarkeCalculates.com and look it up. I didn't know about this. And get this. So you can basically describe anything in a measurement of whatever you want. So somebody is eight Big Macs tall. So you can select Big Macs, Olympic swimming pools, all the stuff that we've ever used to essentially describe the size or shape or volume of something you can now do on JoshClarkeCalculates.com. Why am I just now learning about this? Because I kept forgetting to mention it. And he showed it to me before, I guess he showed it to me in Chicago when he came to the show. All right. I'm looking at it now. Josh Clark Calculates, the weirdest way to measure absolutely anything. Right. The space, then the example in the home page is the space shuttle endeavor has the speed of how many washing machines. And you press a button and it says, beep, boop. The space shuttle endeavor has the speed of 22,778 washing machines. Yeah. And he was telling me like that's like those are legitimate measurements, like comparisons. Well, this is my new favorite home page. Isn't that awesome? Yeah. That's very cool. He is so cool, man. Love Brandon. We'll have to get a band name generator or something going. Oh, that's a good idea too. All right. That was a lot of fun. I feel like we should take a break. Everyone can go visit that website and calculate some stuff. And we'll be back with more about Eels. Okay. Chuck, we're back. Now we're going to talk about my favorite kind of eel. Is this your favorite kind of eel? Yeah. These cute little guys look like plants. Yeah. So I've seen these before. I had no idea they were eels, but they're like, yeah, little worm-like stems sticking up out of the sandy bottom, waving kind of back and forth with the current. And there's so many of them. It does. It looks like just kind of a field of plants. But if you zoom in, they are these cute little eels with cute little faces. Just eating plankton that goes past and they spend most of their lives cemented in the sandy bottom. Even though they're able to get out and move free, that's just kind of where they live. It's also their hidey hole too. Yeah. They're called garden eels. And I think when they get startled, they, their whole body goes back in their little burrow. Yeah. But yeah, these are the ones that can hang out together. So it'll look like a little field of seagrass. There'd be thousands of these little guys just waving around. Yeah. They're so cute too. Just look up Garden Eel and look at their little very serious faces. If you are an eel that's living deep in the ocean, you're not going to be one of the colorful ones. You're probably going to be black or dull gray. And the Gulper Eel is another one that you should look up when it's safe to do so. This is, it's also called the Pelican Eel. They're all over the world basically in tropical and temperate climates. And they are very deep dwellers, like five to 10,000 feet below the surface. Yeah. And they look crazy. They're a few feet long and their jaw is really the star of the show. It's a lot bigger than their skull and it can unhinge and act as a scoop. It looks sort of like, well, I mean, they call it Pelican for a reason. It looks Pelican S, but it's shaped like a shovel. Like if a shovel in a bucket got together and made it, this is what it would look like. Yeah. And it doesn't always look like that, right? So when it like changes shape, it looks extremely alien. It's really neat. The video I saw was Gulper Eel Balloons, its massive jaw on Nautilus Live. And it's just amazing to watch that thing do its thing. Yeah, I agree. Very, very cool. This is, this next section to me is kind of one of the most astounding things that I didn't know about. It is the fact that eels have a real big significance in human history. And especially in medieval Europe, but we're talking mainly about the American eel, the European eel and the Japanese eel. These are freshwater eels. They go to spawn in the oceans, but they live in freshwater and they were a huge, huge source of food for a very long time in a lot of parts of the world. Yeah, it still are. Japan loves eel nagi. Oh yeah. So yeah, one of the reasons why they played such a role as a food source around the world is that number one, they were easy to come by. Like literally, they're swimming around in streams and rivers all over the Northern Hemisphere. And in addition to that, they're really, really nutritious. It turns out high in protein, lots of vitamin B12, vitamin A, vitamin D. That's hard to come by if you're not out in the sun. Yeah, B12, for God's sake. Yes, and only 375 calories for an eel fillet, which is actually pretty new calorie dense for a fish. But it's very good for you too. Yeah, a lot of good fat and protein in there as well. And that eel nagi that I used to love to eat, I would cook it up myself. It was delicious. Oh really? You cooked it yourself? Yeah, I think I talked about this before. There's, near the decab farmers market, near where I live, there's the... Eels thingin'? The first Oriental market and they sell eel as well as lots of like kitchen wares and kind of cool stuff from Japan. But yeah, you can go get eel there out of the fridge and bake it in your oven and coat it with some... I use teriyaki, but I think traditionally is the kabeyaki sauce is used. Is that right? To grill those things up. And it's... I mean, kabeyaki is basically the same. I think it just doesn't have... I think it's like a stripped-down teriyaki. It doesn't have ginger and garlic in it. Yeah, I think it's also a little thicker too, right? I don't know. I think it's about the same, but it's just... It's kind of just the sweet stuff. It is very good. I agree with you. Nothing in here really put me off of eel, especially unagi. Hey, that's good for you. One of the things... You haven't screamed yet. We haven't reached that part yet, huh? No, no. Okay. So one of the reasons unagi is, I guess, noteworthy in Japanese culture. One, as far as sushi goes, it's one of the rare parts of sushi that's ever cooked, like across the board. Yeah. And then number two, it's called one of the big four foods of the Edo period, which I think ran from the 17th century to the 19th century. Those four were soba, sushi, and dr. Pepper. I know this answer, so you didn't get me this time. What is the other one? The other one is tempura. And you mentioned it's the only one that's like routinely cooked because you have to, because eel blood is toxic to humans. So you have to grill that stuff up just right. Yeah. This is one of the things that astounded me, is I didn't know that it was such a big deal in the Northeastern US and Eastern Canada before and after colonization. So indigenous peoples loved eel. I think eel's made up about a quarter, more than a quarter, of the fish found in streams along the coast of the Northeastern, Northern America. And you could smoke it and carry it with you on the trail. You could salt it and cure it, and obviously you could trap them and grill them up. Yeah. I think one of the things that I've read somewhere is that like an eel filet, it does not taste fishy. I saw it compared to a taste of venison even. My experience with eel has never been like that. It's always been like a little bit like on sushi. Did you ever eat like a big hunk of eel at once? No, it's always just been like you would eat on sushi, but they come in a long eel-like package. Sure. And you just bake it in the oven. I think they're already pre-cooked. Oh, got you. Okay. Okay. So they may be shrunk or something, but you're basically just heating it up and glazing it. I got you. Smoked eel sounds kind of good. I would try smoked eel. Yeah, it sounds really good. So it wasn't just the indigenous peoples of North America who were eating eel. The people in Europe at the same time were crazy for eel and had been for centuries and centuries. Apparently they found old willow traps, which are basically like woven baskets that are easy to get into and hard to get out of that eel would swim into and they'd be like, oh no, not again. And they would become smoked or salted or dried. And very interestingly, Chuck, they would often be used as currency. That's how valued eel were, but also how common they were, too. Yeah, this is the fact of this episode for me. Had no idea that in medieval times, not at medieval times, but during medieval times, about half a million dried eels were used to pay rent in England every single year. Yeah, for all sorts of debts. And I mean, it continued on for a very long time into Kill a Mockingbird. Walter Cunningham from Old Serum pays Atticus Finch in a thousand live eels in one point. Is that for real? No. Oh man, I've never wanted to cuss so bad on the show. No, and the reason why that's a giveaway, Chuck, is that I said live eels. Nobody wanted the live eels. They wanted them prepared, smoked, dried. And then depending on how many were put together, did you see like there were different names for like 10 eels together or 25 eels together? Like wrap them up and what was a stick was one? That's like 25. Okay. And then no, that's 10. Yeah, a bind is 25. And those are basically, they were treated like denominations. Like, I'll give you a bind of eels for that. Can a Dr. Pepper. Yeah, two vines and a stick. Yeah, pretty much. That'd be 25 or? It'd be 60. We should type it into Josh Clark Calculate. It'd be like, does not compute. There needs to be one in there for Josh Clark Calculate. So it's like, how many eels would it take to live in the East Village for a month? That's a good one, man. Whatever year? 10 trillion eels. Or how many sticks is that? That's a trillion sticks. Okay. Thank you. That was an easy one. They were very popular food wise though, during church holidays and during fasting seasons because, and this is like up to like a few months out of the year or more than that, 120 days. Yeah, that's like six months. A quarter of the year. Oh yeah. A third. Oh God, here we go. A third. A third. All right, I'm going to type it into your website again. You could not eat meat, but you could eat fish during those fasting seasons. So because there were so many eels, they were, you know, it was a pretty attractive meal. Yeah, a nice meal of eels. That's right. There was one other reason too that we'll see why they were highly thought of for fasting during Christian or Catholic, I guess, feast days was that they have long been considered asexual because as we'll see that like people have no idea how they reproduced and I thought that was pretty interesting. Yeah, super interesting. Like regular fish that have sex would just make you think of nothing but sex while you're eating them, I guess, but an eel, you're all good. Yeah, I mean, should we take a break or should we talk about the reproduction now? I think we take a break, man. Okay. All right, we're going to talk about how they reproduce right after this. All right, everybody, back to the mystery of eel reproduction. In the old days, in the classical Mediterranean era, they had all kinds of crazy ideas about how eels reproduce because they seemed to just appear. No one ever saw them doing it. No one ever saw eel eggs. People had cut eels open and found no reproductive organs. They were, seems to be unusually preoccupied with this, in my opinion. They had a lot of weird opinions and theories as well, right? Sure, sure. But imagine if like, you know how much cow or say chicken. Okay. Humans eat a lot of chicken. Imagine if while you're eating chicken, you're like, where the hell do chickens come from? No one has any idea. I love this chicken, it's delicious, but I have no idea how chickens are born. Yeah, I mean, you probably should have picked something that doesn't lay an egg in front of you. But yeah, I get what you mean. But I think that's another reason why the mystery is so deep is they're like, yeah, chickens lay eggs, pigs, they'd love to do it. Like, they knew how everything else came about, basically. Eels, they're like, I guess they just spontaneously generate. Yeah, for sure. Finally, in 1777, there was an Italian surgeon and researcher named Carlo Mondini. And he finally, don't ask me how, but he finally located the ovaries of an eel. And they, for decades, no one could replicate that fact. And then eventually they found the testicles as well. And no less than Sigmund Freud was one of the, one of the people looking for those eel testes. My friend, he was the one who found them. Yeah. I mean, he'd eat, this was earlier in his career, but he dissected 400 eels, I guess he, on the 401st, found them. Right. It's always the last eel you look in. Yeah. So yeah, so Freud was the person who identified, for the first time, people have been thinking about this for 2000 years at least, how eels reproduce. But at the same time, they're like, great, they have gonads, they have ovaries. Where do they, like, why don't we ever see them using these things? Why don't we ever see their babies? This is all very weird. So the mystery continued even after Freud, although it was really kind of starting to heat up around that time. I think Freud found the gonads in 1876. And within a couple of decades, I think within a decade, they had far more material to work with than they had. So like, it went from 2000 years of not knowing what the heck was going on to bam, bam, bam, we almost have it figured out. Yeah, for sure. Like, we knew that they metamorphosize. We knew that those glass eels, they're basically transparent little babies, they would show up in coastal waters every spring. And they knew that they shurned into adolescent eels, they're called elvers. And they know that they would eventually turn color and swim up rivers. And they knew they would eventually become yellow eels and that they love to eat those things. And then eventually they would become silver eels is the final stop on the eel train. Sure. And that is when they develop the equipment to reproduce and go up river into the ocean. But the part between silver eels going from the river and then the glass eel floating around was the mystery. Yeah. But if you put those two things together, like, okay, the glass eels show up on the coast, the silver eels swim out to sea, seems like that these freshwater eels breeding grounds are somewhere out there in the oceans. Got it, B, right? Yeah. So before that, there was this idea that there were these little things almost plankton like organisms, or I think they were plankton, which apparently the definition of plankton is any floating sea life that just gets moved along by the current can't move around itself. There were these little tiny floating, I guess they were shaped like willow leaves. And they were identified as leptocephalus brevirostus, rostris. And they thought this was a whole different type of fish. And it turned out what they were looking at were the larvae of eels. They misidentified them as something and it took like a couple of decades before they were like, no, this is actually eel larvae. And they found out thanks to a French game named Yves de Lodge, who probably was quite surprised when he put one of these things in a tank. Yeah, he put one in a tank and saw it go through every metamorphosis, I guess. I would assume he kept getting bigger tanks unless he had a big one to begin with. But eventually it became a glass and then an elver. And then about 10 years after that, there was an Italian zoologist named Giovanni Battista, who saw this happen out in the wild. And so, all right, we really are cooking with gas now. But where do those little silver eels go? Where are they going to make this larvae? They still hadn't figured out that part. Yeah, once they mature. So there's a Dutch marine biologist named Ernst Johan Schmitt, which is a great Danish name. I think I said Dutch, right? He's a Danish. Yeah, he's Danish. Sorry, Danish people. He was supported by the Carlsberg Foundation, and yet they were founded by the beer company. Yeah. And they essentially funded scientific expeditions and they funded Ernst Schmitt. And he started, he just basically set out to figure out this mystery of how silver eels produce the little willow leaf larvae. That's right. So he started fishing, casting his nets along the coast. And he found them in the North Sea. He found them in the Mediterranean, and they were pretty big by this point. So he was like, I don't think this is where they started because they've grown a little too much. So he got together with some commercial fishing boats, said, hey, I could use some help because you guys are all over the Atlantic. And they helped him out. And in 1912, he had a report finally to publish that said these little small larvae and silver eels are, which is the end stage, all the way out in the mid-Atlantic, in the middle of nowhere. Yeah. So he was like, I think that they probably breed in the Sargasso Sea. And he never found them. He never saw that they were in the Sargasso Sea, but it turned out he was correct. That's right. Sargasso Sea apparently is a pretty rich breeding ground for a lot of reasons. One reason because of the brown Sargasm that floats on top, I think it just creates a nice covered shady habitat. Yeah. And it's not just the eels. I think a lot of things reproduce in the Sargasso Sea. For sure. And the reason the Sargasso Sea is remarkable is it's a sea in the Atlantic Ocean. Yeah, for sure. And it's kept in place by, I think, four currents that come together and create a gyre. And in the middle of this gyre is what we call the Sargasso Sea. And it's relatively still compared to the rest of the ocean. It's very high in saline. And it stays pretty warm. It's largely off the coast of the Eastern United States, I believe, where it's mostly situated all the way out to the Azores. Azores. Azores. Azores. Sure. And it turns out that in, I think, 2018, a European team led by Rosalind Wright found out that, yes, Ernst Schmidt was correct, that they do, eels do actually mate in the Sargasso Sea. That's right. Now, that's those. There are other freshwater eels that spawn in other places, obviously. They don't all go there. I think Japanese eels spawn at these underwater mountains around the Mariana Ridge, which is pretty incredible. So neat. Yeah. Yeah. And then, I think, African longfin eels spawn in the Indian Ocean. And you might say, like, who cares? Like, yeah, it was a mystery. But think about this. Eels are like halfway up the Rhine in Germany. Yeah. And they're like, well, it's time for me to go reproduce. I'm getting to be that age. They swim all the way down to the Atlantic Ocean, swim all the way across the Atlantic Ocean to the Sargasso Sea. That's where they mate. And then their little tiny larva, these little floating plankton, make their way all the way back to Europe again, where they turn into glass eels, then alvers, and then swim back up, and take their place up the Rhine until they do the same thing. That's a very strange reproductive strategy, but that's what eels do. Yeah. Eels are like salmon. Please. Exactly. Yeah, there's a word for it. I can't quite bring to mind. I want to say catacephalic. That might be it. But essentially, it's they're born in the ocean, but they live their lives in freshwater. Yeah. Yeah. Yeah. What was that word? I remember seeing it now. Catacephalic. It's probably wrong, but I'm going to say that authoritatively. All right. So today, eels, the International Union for Conservation of Nature, the red list, Lysim as the threatened species, the European eels are critically endangered, and the American Japanese and New Zealand longfin eels are endangered. Okay. I'm screaming now. I can see that. Yeah. Because they're endangered, and then some of this other stuff to come was a pretty big turn off for me as far as eating them goes. Yeah. I guess that puts me off of eating eels too. Hey, no pressure, bud. American and European eel populations have dropped by more than 90% since the 1970s. Yeah. Same with Japanese eel populations. Hydro power turbines and dams is a big reason. We know that they disrupt all sorts of underwater aquatic life, but also overfishing the loss of wetlands and pollution. So the eels that you eat, and this almost got me back on it, they're raised in aquaculture facilities. They aren't bred in captivity because it's really hard to do, as obviously that we've seen their reproduction is pretty tricky overall. Right. So if they were to try and do that, they would have to introduce hormones to induce sexual development. Keeping those larvae alive is really difficult in captivity, just because of the organic matter that exists in the wild, like they really need that stuff. So what they do is they capture those little glass eels in the wild and bring them to the farms to raise them to maturity so you can eat them. Right. And one of the reasons, maybe the reason that American and European eels have dropped by 90% since the 70s is that when you're taking these glass eels out of the ocean, number one, you're preventing that same number of eels from ever growing up to reproduce because they're going to get eaten before they get a chance to. And two, if eels follow any kind of typical evolutionary strategy, they probably have a ton of larvae and a huge percentage of them die off and the glass eels are the ones that make it. So what you're doing is saying, like, thanks for the surviving larvae, everybody. We're going to take them and eat them. So that prevents an entire species from reproducing for the most part. And that's why their stocks have died off from those fisheries. Yeah. Yeah. I think we skipped the part where like, didn't they tag eels to track them? Yeah. That's how they found out Rosalind Wright in 2018. That's how they found out. But yeah, I forgot to mention that part. Yeah. Crazy to tag a little eel. Maine, the US state of Maine, is the only state that has a glass eel fishing industry. They have licensed what they're called Elverman because remember the Elvers is the third, I guess the penultimate stage. They're 425 licensed Elverman that can harvest around 7,500 pounds between late March and early June every year and then they ship it off to Hong Kong. Very nice. Do you know what the third to last is called? Oh, is that a word for that? Are you about to dupe me? No, this is for real, Chuck, I promise. Okay. What? It's anti-penultimate, but like ANTE, like anti-chamber, anti-penultimate. Yeah, I like that. That always reminds me, and I think I mentioned this in the Gary Larson episode, the second to the last of the Mohicans cartoon, which is just a big line of indigenous, I guess, Mohicans, and the last of the one in line, everyone's facing one way and he just turned around and waving and smiling. How great, man. Yeah. That guy. You got anything else about eels? No, that's it. Okay. Yeah, if you want to know more about eels, go watch videos about David Byrne and see what Booksy recommends. You can also visit your local aquarium. You can also go online and visit the website of your local aquarium. There's all sorts of stuff you can do to learn more about eels, and I urge you to and maybe stop eating them. I'm going to too, okay, Chuck? Really? I'm going to stop eating American or European eels for sure. All right, no more unagi for us. No, it's been a while since I had it anyway, so it's not like it's a huge give up for me. The gloss. All right, good. Well, since Chuck agreed that we're both going to give up eel, it's time for Listener Mail. This is from Alex, and this is a follow-up about the baking soda and coconut oil deodorant from the Listener Mail. Apparently, Alex is sort of an expert on this, so again, tread carefully whenever you're applying anything to your skin and body. Can you refresh my memory? I don't remember that deodorant. Basically, baking soda and coconut oil, if you mix together into a paste, can be a good natural deodorant, but it can also chafe your skin and cause outbreaks if you don't get the mix right. Okay. So, this is what Alex says. I've been doing this for the better part of 15 years, guys, and have continuously adjusted the recipe to balance what I found to be three main factors, odor-eliminating effectiveness, skin reaction, and staining of clothing. Baking soda is responsible for the first two and needs to be carefully balanced to be effective enough, while not causing a rash. Coconut oil is commonly used to act as a concentration reduction and application medium, but it stains the clothes. I found that cornstarch is excellent at being a neutral alternative to reduce the concentration of the baking soda. I usually go about equal volumes of the two, then add only enough coconut oil to make a thick paste. In a pinch, if I find myself having forgotten to use deodorant, I will moisten my finger and dab it directly in baking soda, so that it is only very lightly dusted and then rub that on my armpits. But don't do that too often, guys. You'll end up with unhappy pits, but it's a great backup because most people have a box of baking powder opened in the fridge and don't care about fingers in it because it's not there for eating. A girlfriend from another lifetime once told me I should start an armpit empire. And by the way, guys, I'm in Puerto Rico, so if you ever feel like coming to do a show in the tropics, I'd be the first one out telling everyone to buy tickets, and that is Alex. Thanks a lot, Alex. Can you just see Alex dipping his fingers in some baking soda and rubbing him on his armpit and saying, ah, refreshed. I can just see it. If you want to be like Alex and give us even more detail about a whatever it is you know a lot about, we would love that. You can send it to us at StuffPodcast at iHeartRadio.com. Stuff You Should Know is a production of iHeartRadio. For more podcasts, my heart radio, visit the iHeartRadio app, Apple podcasts, or wherever you listen to your favorite shows. This is an iHeart podcast. Guaranteed human.