Drunk Monkeys, Heroic Rats, Forehead Teeth

Carly York joins the show to talk about the most heroic rats you'll ever meet. Plus, Sara Kiley talks about some drunk monkeys, and Rachel gets into sharks' toothy foreheads. The Weirdest Thing I Learned This Week is a podcast by Popular Science. Share your weirdest facts and stories with us in our ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Facebook group⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ or ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠tweet at us⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠! ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠Click here to learn more about all of our stories! ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ Links to Rachel's TikTok, Newsletter, Merch Store and More: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://linktr.ee/RachelFeltman⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ Rachel now has a Patreon, too! Follow her for exclusive bonus content: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.patreon.com/RachelFeltman⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ Link to Jess' Twitch: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://www.twitch.tv/jesscapricorn⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ -- Follow our team on Twitter Rachel Feltman: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠www.twitter.com/RachelFeltman⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ Produced by Jess Boddy: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠www.twitter.com/JessicaBoddy⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ Popular Science: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠www.twitter.com/PopSci⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠ Theme music by Billy Cadden: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://open.spotify.com/artist/6LqT4DCuAXlBzX8XlNy4Wq?si=5VF2r2XiQoGepRsMTBsDAQ⁠⁠⁠⁠⁠⁠ Thanks to our Sponsors: Visit ⁠https://GrowTherapy.com/WEIRDEST⁠ today to get started. Go to ⁠https://Quince.com/weirdest⁠ for free shipping on your order and 365-day returns. Learn more about your ad choices. Visit podcastchoices.com/adchoices

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Speaker 00

  Hey Spotify listeners. When you travel with American Airlines, you'll enjoy comfort and convenience at every altitude. Before takeoff, unwind in the Admirals Club Lounge with curated self-serve offerings of hearty bites and refreshments. In flight, stay connected with high-speed Wi-Fi. Sponsored by AT&T. Your journey is designed to feel easy from the moment you check in to the moment you arrive. No matter where you're going, American gets you there. Book now at aa.com.

• 0:27Speaker 01

  This episode is brought to you by Google Chrome. You think you know a browser, but Gemini and Chrome, that's new. It can help you with practically anything on the web, like restoring a vintage motorcycle from a 50-page restoration block or finally break down that long article you've had open for weeks. Gemini and Chrome is here for it. Ready to make anything online make sense? There's no place like Chrome. Check responses set up required. Compatibility and availability varies 18 plus.

• 0:52Speaker 02

  Stonefire naan is made with real buttermilk and ghee. It's the perfect flatbread for any occasion.

• 0:57Speaker 03

  I put out Stonefire naan with dips at every dinner party.

• 1:00Speaker 04

  I make naan-grilled cheese when my daughter has friends over.

• 1:03Speaker 05

  I use Stonefire naan to reward the humans who do my bidding.

• 1:07Speaker 06

  Right. It's perfect for camping trips. Dance for it, feeble mortal. Sorry, is he talking to me or... Dance.

• 1:17Speaker 07

  From our tradition to yours, Stonefire. Together we naan.

• 1:26Rachel Feltman?

  At Popular Science, we report and write dozens of science and tech stories every week. And while most of the stuff we stumble across makes it into our articles, we also find plenty of weird facts that we just keep around the office. So we figured, why not share those with you? Welcome to the weirdest thing I learned this week from the editors of Popular Science. I'm Rachel Feltman.

• 1:46Speaker 09

  I'm Sarah Kylie Watson.

• 1:48Rachel Feltman?

  I'm Carly York.

• 1:50Rachel Feltman?

  Carly, welcome to the show.

• 1:52Speaker 11

  Thank you.

• 1:53Rachel Feltman?

  Would you tell our listeners a little bit about who you are and about the awesome book you just put into the world?

• 2:00Speaker 11

  Sure thing. So I am a scientist. I'm an animal physiologist and a biology professor. So I study how animals' bodies have adapted to be in different kinds of environments. And I have studied a wide variety of animals. I've done some like horse stress physiology. And then I decided I wanted to study squid after that, as one does. And now I'm doing some sensory work with frogs. So yeah, a lot of different kinds of animals. But I have also been writing. I still, I have a hard time calling myself a writer,

• 2:42Speaker 11

  but I guess I am. So my latest book is The Salmon Cannon and the Levitating Frog. And it is about the value of curiosity-driven research. So this is research that does not have an immediate application. And it might take decades for us to know like how it's useful if we ever do at all. But it's incredibly valuable, this research. And it's, the book came out sadly pushing time because we're seeing like massive cuts to this kind of research. So I didn't know that when I started writing it, but we're not in a great place right now.

• 3:23Rachel Feltman?

  You want to know something crazy? I actually have a tattoo of a squid riding a horse.

• 3:28Speaker 11

  No way!

• 3:29Rachel Feltman?

  Yeah, yeah. It's a reference to something in, not really going to be able to see it, but there's a squid on there. It's a reference to something in Carmen Maria Machado's memoir, In the Dream House, which is one of my favorite books. But when you went from horse to squid, I was like, my God.

• 3:45Speaker 11

  I feel like, I feel like we're connected.

• 3:47Rachel Feltman?

  Yeah, yeah, exactly. Well, anyway, we're excited to have you on the show. So let's get right into it. So on the weirdest thing I learned this week, we start by each offering up a little tease about some kind of fact or story we found in the course of reading, writing, reporting, et cetera, and decide which one we just absolutely have to hear more about first. Then, once we've all had time to spin our little science yarns, we reconvene and decide what the weirdest thing we learned this week actually was. Though today, I feel like the weirdest thing we learned this week is that I have a tattoo of

• 4:16Speaker 09

  Hard to be.

• 4:18Rachel Feltman?

  The two very distinct animals that you have studied. Sarah Kylie, what's your tease?

• 4:23Speaker 09

  Okay, so mine is that wild trimps quote unquote, "drink alcohol every single day."

• 4:31Speaker 09

  Yay!

• 4:33Rachel Feltman?

  Good for them. I get it. I understand. My tease is that there are fish with teeth on their heads for sex reasons.

• 4:45Speaker 09

  Nice.

• 4:46Rachel Feltman?

  Yeah, and good for them. Carly, what's your tease?

• 4:50Speaker 11

  Well, mine isn't nearly as spicy. I'm just going with rats save lives.

• 4:54Rachel Feltman?

  I mean, also good for them. Thank goodness for them.

• 4:58Speaker 09

  And surprising.

• 4:59Speaker 11

  It is surprising.

• 5:00Speaker 09

  Maybe more surprising than the other two.

• 5:04Rachel Feltman?

  Sarah Kylie, would you kick us off with, with drinking?

• 5:06Speaker 09

  Yes, of course. Oh, gosh, I'm so excited about this one. Yeah. So this is a big topic, which lots of people have lots of opinions about. But I'll start at like with us, with, with us, primates, humans, because we and alcohol go way back, like really, really way back. And that is like an evolutionary perspective, not just like people have been brewing up mystery beer for thousands of years. So like 10 million years ago, basically the study that came out about a decade ago, researchers found out that this common ancestor to humans, chimps, and gorillas, this, yeah, 10 million years ago, this creature that is our ancestral cousin had an enzyme to break down alcohol. So basically, this kind of like

• 5:51Speaker 09

  Alcohol's been a part of our existence even before humans were humans. And this kind of makes sense, and it will start to make even more sense as we dive into it, because stuff ferments in the wild. You know, in a world where we don't have like perfectly curated bananas on the shelf for you to go grab, you're gonna probably end up eating some fermented fruit, because fermentation is just what happens when yeast and sugar molecules get smushed together, and the molecules kind of produce alcohol to say like, "Back off!" And it creates this antibiotic material, and it accumulates at low concentrations in fruits and nectar. So that's just, you know, part of being a something that eats fruit and nectar, is that you're gonna bump into some alcohol.

• 6:33Speaker 09

  But this discovery, along with, you know, decades of research, has kind of led to this hypothesis called the drunken monkey hypothesis, which was first proposed by Robert Dudley, who's a UC Berkeley professor back in 2004. And he published a book about it in the same year as the 10-million-year-old alcohol enzyme study. So 2014 was a huge year for people and alcohol, which ironically was my freshman year in college. So a huge year for humans and alcohol in my book. But the idea goes like this, that alcohol is routinely consumed by all animals that eat fruits and nectar, like even, you know, birds and things get a little bit of alcohol.

• 7:14Speaker 09

  And there's a couple of reasons why this, obviously fermenting on its own, and that also like fermented fruit and, you know, wine, all of these things that have alcohol in them smells. And it basically gives off this smell that's like, "Hey, like fruit that's just about to be not good anymore over here. Delicious, come gobble me up." And of course, there's also the element of that we're, you know, still like maybe in the process of being studied, especially in other animals, is that alcohol makes us happy. You know, we are happier, we're more social, we get that boost in energy. And so Dudley wrote about this in Quartz a couple of years ago, but like for animals searching in a rainforest for nutritional resources that could be scarce,

• 7:58Speaker 09

  it's a good idea to consume these ripe fruits as quickly as possible before the competition arrives.

• 8:03Speaker 03

  So.

• 8:04Speaker 09

  Lots going on in the world of are monkeys getting drunk? And at first, people didn't really think that this held a ton of water, but there's been a lot of developments in terms of like watching our evolutionary cousins consuming alcohol in the wild and in captivity. And so a couple of examples of those. So scientists at the University of Exeter recently captured this footage of wild chimps kind of eating and passing around African breadfruit, breadfruit in West Africa, and at least 10 different situations. So there was like some like monkey alcohol hangouts going on very recently. And in 2016, Dartmouth researchers found that they were doing some experiments with

• 8:46Speaker 09

  two aye ayes and a slow loris, which I'll explain what those things kind of are. But basically, they found that these creatures, which are our evolutionary cousins, although aye ayes are from Madagascar, so they're in a league of their own. But they still apparently have this 10 million year old hay enzyme for breaking down alcohol. But they could tell which nectar samples had more alcohol and they wanted those. So that is fascinating stuff. And then basically.

• 9:17Rachel Feltman?

  I want to go to a wine tasting with an aye.

• 9:19Speaker 09

  Oh, my gosh, my dream, my actual dream would be to do that. And I'm like, we've, there's so many things. I want to now do all of these. I want to go to Napa Valley and watch people drink alcohol now, now that I've researched this. But yeah, so and basically, so Dudley and his team is also, they're also doing a bunch of this research, obviously out of UC Berkeley. And a couple of years ago, they found that Panamanian black handed spider monkeys go for fermented fruit in the wild, like they prefer to find the more fermented fruit in the wild. And then they tested their urine and they saw that like the alcohol is being metabolized. So it's not just like, they're not just peeing it straight out, like they're using it for energy, yada, yada. So there's all of this research where we're kind of learning more about what our, yeah,

• 10:03Speaker 09

  our evolutionary cousins are doing in terms of alcohol. But the, the key driving question behind all of this is not, are they? Eating alcohol laden stuff, which in many cases, yeah, that appears to be the case. But are they like actually getting drunk? Is is anyone acting sillier after having a little gathering with your chimp friends and sharing some lightly rotten fruit? But yeah, so the latest drunk monkey shenanigans kind of came out a couple of weeks ago. It's a new study and this time it's all about chimps, which they haven't been looked at as much. Clearly we had that study from a couple of months ago, but like I mentioned, it's like eye eyes and spider monkeys and all these other guys. But chimps are our closest buddies.

• 10:45Speaker 09

  We only diverged from them like 6.5 to 7.5 million years ago, which in the grand scheme of things is not that long. But yeah, human and chimp DNA is like pretty much like almost, it looks almost identical if you like line it up and it's like 99.8% the same. So we're very, very tight with chimps, which you know, it's always fun to think about. But yeah, so basically this time it's Dudley's team and some other researchers, of course. Then they followed around a group of wild chimpanzees in two different locations in Uganda and on the Ivory Coast. And basically what they did was they yeah, like lurked around, watched the wild chimps do their thing and they scooped up samples of the fruit that they saw these wild chimps go for, basically like the undamaged freshly fallen fruits on the ground near the trees that had been recently forged by chimps.

• 11:30Speaker 09

  So basically we're yeah, scooping up chimp leftovers. And then they kind of tested for alcohol content, content using like they had, there's one device that's like a breathalyzer, they had a chromatograph and a chemical test. So a bunch of different ways to say like, how alcohol filled are these fruits anyway? So what they found is that in the course of a day, wild chimps consume about 14 grams of pure ethanol, which is adjusting for body mass and all of that fun stuff, like about the similar amount to a human having more than a drink a day or a drink and some. And these fruits have like an average alcohol content of around 0.26% by weight, which doesn't sound like a lot, but when these chimps are eating 10 pounds of fruit a day,

• 12:13Speaker 09

  which is like 7 to 14% of their body weight, that adds up. And on top of just the generalized alcohol fruit of it all, the chimps kind of preferred this fig and this plum at the respective locations that were the highest alcohol content. So not only were they having a little booze with their fruits, they were preferring the ones that are even boozer. And there's a couple interesting things to unpack here. And obviously, the first is the question of if the chimps are getting drunk from this, and it doesn't really look like it, is what the others say, like, nobody was acting.

• 12:46Rachel Feltman?

  Well, they're getting so much fiber.

• 12:48Speaker 09

  Right, yeah.

• 12:49Rachel Feltman?

  It's just, it really seems like they, they, they have no choice but to pace themselves.

• 12:54Speaker 09

  And that's exactly it is that like, whereas we, we can have as much alcohol as you can take, because it's not filling you up, right? But like, if you're eating fruit, like, you're gonna be so bloated and sad if you try to have more than like this amount of alcohol. And at the end of the day, if it's like a, you know, like a beer a day, and it's like spread out throughout the whole day, it's, it's just nothing. It's like, you would not feel that unless you are like the tiniest person on earth. So, I mean, who knows, maybe, but I don't think I would. I would be too distracted by the eating. So that's basically what's happening is they're, they're being very responsible with their food to alcohol ratio, and therefore not getting wasted in the

• 13:35Speaker 09

  jungle all the time. But, but yeah, so now they're kind of doing this like next, the second part, which was kind of like with the spider monkeys, where they're now catching the pee, which is fascinating. It, it sounds like it's like you kind of like have to like actually walk around with like an umbrella catcher of pee under the chimps to get the pee, or you have to like pipet it off of leaves. It sounds like it's a whole thing. But now they're figuring out if like that same metabolic shenanigans is happening, where it's like, okay, they're not just peeing out the alcohol, it's actually like going up and into their brains and all throughout. So we're figuring that out. But it's, I mean, seems like that might be the way that things go. But the other part is, again, that these chimps are wild. These are not like in a zoo somewhere and

• 14:18Speaker 09

  The, the diet of a wild chimp versus a chimp in captivity is really, really different because chimps in captivity are not doing a ton, so they're not eating a ton. And also they're eating like fruit that humans are kind of like have been in charge of in farming. It's not just like jungle fruit, which has been sitting in the sun, potentially fermenting. So it just like kind of opens up this question of like, are they getting the nutrient that is alcohol? Because they're kind of like, they're, they're like sober people. Like they're not like getting it in the same way that wild chimps are. So it kind of like opens up this question of like, are they getting what they need?

• 14:59Speaker 09

  Because there are a lot of benefits to fermented food, which like alcohol is fermented food at the end of the day and in a, in a cute bottle a lot of times. Because like we think about things like yogurt and kimchi and the probiotics and how that helps like your gut be strong and healthy and happy. And if captive chimps aren't getting their fair share of fermented fruits and even again, like people, like what are the health implications of that? So that's like one of the big unanswered questions with the drunk monkey stuff. And like, so basically, but like knowing all of this, it kind of just like also opens up what it means for like, why humans are drawn to alcohol in general? Is it an evolutionary thing?

• 15:41Speaker 09

  And I, I got to talk to the lead author of this study, which was always so fun, Alexi Mauro, wonderful, wonderful chat. But basically some of his hypothesis is behind like, hey, like what does this actually mean for human evolution and like human issues? Like alcoholism is not a joke, obviously. And unlike chimps, like we can, we, we can drink kind of non-stop. We don't get full from, from fruit. So it's kind of just asking this question of why did we develop alcohol in the way that we did? Is it filling some kind of like evolutionary mismatches, the way that he described it? Like when the, when the ecosystem started to change and we were like, hey, we, alcohol means good food. Like did the brewing come as part of that?

• 16:23Speaker 09

  It's kind of like a technology to help humans get through scarce or changing ecosystem times. So lots of just like really interesting opened doors from this like fascinating study of basically following around wild chimps and picking up their leftovers.

• 16:41Speaker 09

  Which is always fabulous. But yeah, like the moral of the story here is that yes, chimps are ingesting alcohol. We know that officially for the first time that chimps out in the wild minding their business are getting, they're getting a beer. They're getting a beer every day. And are they boozing enough to act, act drunk? Probably not. But you know, until we get, until we can see it all over and over and over again, and keep exploring this, it's just, it's a conversation for a glass of wine, if I may say. But yeah, that's, that's the scoop on the, the latest with the drunk chimp drunk monkey hypothesis.

• 17:20Rachel Feltman?

  I love, my favorite aspect of this study is just thinking about how much fiber a chimp would have to consume to have like multiple drinks a day, you know, the equivalent and just like how immediately unpleasant that would be from like a bloating uh, over full perspective and how probably humans would drink less if we had more immediate nasty feelings. That having, having most of the nasty feelings be the next day, maybe doesn't, doesn't do us a lot of favors.

• 17:57Speaker 09

  If I had to have like four cartons of strawberries to get a buzz, then like I assure you, I would not be doing that. No, thanks. I can go without. It's quite all right.

• 18:11Rachel Feltman?

  Okay, we're going to take a quick break and then we'll be back with some more facts.

• 18:20Speaker 00

  Hey Spotify listeners. When you travel with American Airlines, you'll enjoy comfort and convenience at every altitude. Before takeoff, unwind in the Admiral's Club Lounge with curated self-serve offerings of hearty bites and refreshments. In flight, stay connected with high-speed Wi-Fi. Sponsored by AT&T. Your journey is designed to feel easy from the moment you check in to the moment you arrive. No matter where you're going, American gets you there. Book now at aa.com.

• 18:46Speaker 01

  This episode is brought to you by Google Chrome. You think you know a browser, but Gemini and Chrome, that's new. It can help you with practically anything on the web, like restoring a vintage motorcycle from a 50-page restoration block, or finally break down that long article you've had open for weeks. Gemini and Chrome is here for it. Ready to make anything online make sense? There's no place like Chrome. Check responses set up require compatibility and availability varies 18 plus.

• 19:11Speaker 02

  Stonefire naan is made with real buttermilk and ghee. It's the perfect flatbread for any occasion.

• 19:17Speaker 06

  I put out Stonefire naan with dips at every dinner party.

• 19:20Speaker 04

  I make naan-grilled cheese when my daughter has friends over.

• 19:23Speaker 05

  I use Stonefire naan to reward the humans who do my bidding.

• 19:26Speaker 06

  Right, it's perfect for camping trips. Dance for it, feeble mortal. Sorry, is he talking to me or? Dance, ha, ha, ha, ha, ha.

• 19:37Speaker 02

  From our tradition to yours, Stonefire.

• 19:39Speaker 07

  Together, we naan.

• 19:46Rachel Feltman?

  Okay, we're back. And Carly, tell me about some heroic rats.

• 19:51Speaker 11

  I happily will. I confess, this isn't something that I just learned this week. This is something I have been dying to talk about ever since I

• 20:00Rachel Feltman?

  Even better.

• 20:01Speaker 11

  Read about them.

• 20:01Rachel Feltman?

  I'm excited.

• 20:03Speaker 11

  I've actually, I have pitched this to a few places and I've gotten turned down. So I'm really pumped to finally get to talk about these critters.

• 20:13Rachel Feltman?

  Well, we're honored.

• 20:15Speaker 11

  So the rats that I am talking about, they are called African giant pouched rats. And they are not like your typical domestic rat or the one you might see in New York City. They are quite big. They can get up to three feet long, including their tail. They, so they're, they're not our supils. They're not pouched in that way. They, they like to stuff food in their cheeks and they consider that to be pouches. So they have pouchy cheeks. So there's these big pouchy rats. And it turns out they have a really incredible sense of smell. Um, and they are also super duper intelligent.

• 20:59Speaker 11

  So these two features together have made them actually really useful for a few different humanitarian efforts. And that's why they have gotten the name of the hero rat.

• 21:13Rachel Feltman?

  They're also really cute.

• 21:14Speaker 11

  Puffy cheeks. Did you see one with a vest on?

• 21:18Rachel Feltman?

  Yeah.

• 21:19Speaker 11

  Yeah. Yes. So this started with an organization. The abbreviation is APOPO and it translates in Dutch to something close to anti-personnel landmines detection product development.

• 21:34Rachel Feltman?

  Sounds about right.

• 21:35Speaker 11

  And

• 21:37Speaker 11

  and the, the first effort that they really took on was using these rats for detecting landmines. So they train these rats to pick up by smell where a landmine is and then give a little scratch to let their handler know that they've detected a landmine. And what's super cool about them is a dog could probably do this too, but a dog is heavy enough that it would actually detonate the landmine too. But the hero rats aren't there, they're light enough that they won't. So they actually do weekly weigh-ins just to make positively sure that they're going

• 22:19Speaker 11

  to stay below the threshold that would trigger or detonate a, a landmine. So they've been doing this in like really landmine ridden places like Tanzania and Cambodia and Zimbabwe and others. So according to their annual report, their 2024 annual report, they have been instrumental in detecting 1,069, 884 landmines.

• 22:46Rachel Feltman?

  Wow.

• 22:47Speaker 11

  Liberating an estimated 2 million people from the threats that they pose.

• 22:53Rachel Feltman?

  Oh my gosh.

• 22:54Speaker 11

  So it's

• 22:54Rachel Feltman?

  Also, this is the only time I have ever been in support of workplace weigh-ins.

• 23:00Speaker 11

  Oh, yes. Skinny rats.

• 23:02Rachel Feltman?

  Normally terrible, terrible red flag. In this case, yeah, keep, keep those chunky guys from getting blown up. Important.

• 23:13Speaker 11

  It is important. Oh, and I will say I have adopted several of these and

• 23:18Rachel Feltman?

  What?

• 23:19Speaker 11

  Oh my gosh, I was gonna put a plug at the end, but I'll do it now. You can adopt these little critters. If you go to the Apopo website, they have a number of them for adoption. I think I've adopted all of them. And you get monthly newsletters that are really detailed, actually, and it tells you, you know, their weight check-in, but it also tells you their favorite treats that week and how many, how, what kind of, you know, work they've been doing, how was their training going? It's like the highlight of my month.

• 23:50Rachel Feltman?

  Yeah, I gotta check it out.

• 23:52Speaker 09

  This is essential knowledge.

• 23:55Speaker 11

  It is, it is. So, the landmine project, that's been going on for a little while now. And if you think that like they should win an award for their work, they actually have. There was a hero rat named Magua, and in 2020, he received this adorable tiny little gold medal from the UK charity People's Dispensary for Sick Animals for his lifesaving work. And apparently, this is equivalent to the George Cross Award, which is the highest award for a human who shows acts of heroism and bravery. So this is the first time a rat had ever won that award.

• 24:38Speaker 11

  So this is absolutely worth a Google search. There's lots of pictures of Magua and his little gold medal. He was written up like in the New York Times and NPR covered him. And so he got a whole lot of press. His, his record was that he cleared 2.4 million square feet of land. And he found 71 landmines and 38 unexploded ammunitions. So it's pretty impressive. But another one of the hero rats, a youngin, actually just broke Magua's record.

• 25:16Speaker 11

  So Ronan, Ronan is just a young five-year-old and he just broke the record by uncovering one hundred and nine landmines. Wow. So he's a rock star and he still has years ahead of him to keep sniffing out Yeah. these dangers. So amazing stuff and it doesn't end there. So another thing that these rats are being used for is detection of tuberculosis. Oh, whoa. Yeah. So tuberculosis is still an incredibly dangerous virus. Africa has the highest rates of TB in the world with about seventy-five percent of them

• 25:57Speaker 11

  of the approximate one million cases arising globally. And even though it's really prevalent and even treatable, it's often hard to get the equipment needed for detection in developing countries. So, you know, that requires some pretty fancy equipment. It requires trained technicians. It requires upkeep on that equipment. So there's a lot to consider in terms of just like TB detection and a lot is going undetected. For, for example, in Mozambique, more than half of the positive cases of TB actually go undetected. And it's especially tricky sometimes to detect it in children because they have a hard time

• 26:38Speaker 11

  producing enough sputum, which is mucous saliva for an accurate test. But these rats are apparently really, really good at picking out TB in different samples. So they have these incredible olfactory systems and they have these like neural connections that allows them to literally think with their nose. And that allows them to be able to detect the volatile organic compounds in these TB samples so incredibly well.

• 27:14Speaker 11

  So there was a write-up of a specific hero rat named Tariq, who was doing work in Mozambique in, in detecting TB. So the way this goes. Paint a picture. There is like a big glass kind of cage and underneath the cage is a removable tray. And they can pull out the tray and they will put multiple samples into that tray. And Tyreek will go around and he will sniff each of these samples.

• 27:52Speaker 11

  And he's trained so that when he sniffs TB, he'll scratch and let his handler know that he found a sample. So it only takes him eight minutes to go through fifty samples. And that's more samples than a lab technician could test in a whole day. Wow. So they're super fast. They're also really, really accurate, though. There was a study that found that the rats' evaluations increased case detection rate by forty-four percent compared to traditional methods. And there've been other studies that have have supported that as well. So training one of these rats, it costs between like six thousand to eight thousand dollars.

• 28:37Speaker 11

  You know, that's money, but they're relatively inexpensive to maintain. Uh, throughout their life, they're little rats. You feed them and you treat them nice. So compared to the cost of some of these other diagnostic tests, most of which are gonna run up to like close to twenty thousand dollars per device. And that's not even with the upkeep. These these rats are actually really significant in terms of being able to make progress in detection of TB. So according to their twenty twenty-four annual report, six hundred and forty-two thousand nine hundred eighty-eight patients were screened for TB. And an additional thirty-three thousand cases were detected after failing to be detected in a lab test. Wow.

• 29:22Speaker 11

  And because of that, another three hundred thousand other potential infections were prevented by having this detection. Wow. They're incredible. They're incredible. Um, and so these have been the two biggest ones that Epopo has been doing, the landmines and then tuberculosis. But they have two new initiatives that they have been working on as well. One is training them to detect illegal wildlife trade.

• 29:54Speaker 11

  Um, so this one, the, the famous rat who's been working on this, her name is Jane. And she was named after Jane Goodall. She is being trained to sniff out things like giraffe hides or pangolin scales. Things that are commonly seen in illegal trade. And also any animals that might be common in like exotic pet trades. And the way that she does this, she has a little vest. And at the front of the vest is a tag. So when she's going around sniffing stuff, when she detects something that shouldn't be there, she knows to pull on the tag. And then that alerts her handler that she has found something for them to look at.

• 30:38Speaker 11

  The other newer initiative that they're working on is Rescue Rats. These ones are going to be rats that will help with search and rescue missions. So they are equipped with a high-tech backpack that has a camera and a two-way radio on it. And they're trained to go find people. And the camera on the radio isn't on all the time. That would take a lot of energy to just have that running all the time. Instead, they have it like ready to go. And then this rat too is trained to tug on a little tag on his vest. And that will actually turn on the camera and the radio. So that can have communication with this person.

• 31:20Rachel Feltman?

  Wow.

• 31:20Speaker 11

  That you're trying to rescue. So it's pretty incredible. I highly recommend a YouTube watch of these guys. They're adorable and just like, it's so heartwarming to me to see this animal that gets so much hate, just be so, so wonderful. And, and I also got to again, highly recommend adopting a rat or two and supporting this organization. Because not only is it a wonderful cause, but also it's really fun to hear about everything that they're doing and all of the.

• 31:55Rachel Feltman?

  I want to get the rat newsletters.

• 31:57Speaker 11

  Rat newsletters.

• 31:58Speaker 09

  I love the rats. Okay, this is very exciting.

• 32:03Speaker 11

  When I started doing, so I have a little part in my book about the hero rats. And I've been obsessed ever since I wrote this one little part. And I'm truly like, how do I write a whole book about hero rats? It's all I want to do is read about hero rats and talk about hero rats. Like, how can I make this happen?

• 32:24Rachel Feltman?

  It comes up at like every party I attend. I'm sure I'm, my friends are tired of hearing about the hero rats, but oh man, they're great. Oh, I love them. All right, we're gonna take one more quick break and then we'll be back with one more fact.

• 32:44Speaker 00

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• 33:10Speaker 01

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• 33:40Rachel Feltman?

  Okay, we're back and I'm gonna get into my fact, which is about fish with teeth, not just in their heads, but on their heads for sexy reasons. So I'm already on the record as thinking ghost sharks are rad. They all look like they belong in a Timber and Claymation film. There's one that looks just like Zero from Nightmare Before Christmas. And another one that looks like some kind of horrifying skin puppet that's been like stitched together from different fish, which is probably part of why this order of deep-sea fish is also known as chimeras, which of course is a word that means, you know, put together from, from different parts.

• 34:22Rachel Feltman?

  I think also that the name may be a reference to the fact that they're just generally kind of weird looking, so sometimes they'll be described as being like, the nose is very frog-like, whatever. But what One cool fact about chimeras in general, before we get into the main fact, is that they're thought to have these special muscle-filled pores that allow them to sense electrical signals in the water, which true sharks do have. And sharks and ghost sharks are related, but not that closely related. They broke off, like, I want to say hundreds of millions of years ago, but, you know, they're, they're in the same realm. But yeah, true sharks mostly use these special pores to hunt prey. But ghost sharks have them in like different parts of their bodies,

• 35:07Rachel Feltman?

  and they're also very opportunistic feeders. So it wouldn't really make sense for them to be like hunting down the movements of prey. And scientists think that they actually use them to navigate in the darkness of the deep sea. So they have like a spooky sixth sense, kind of, which is very fitting for these spooky fish. But today, I'm going to talk about a specific species of ghost shark, which is called the spotted ratfish, which did not even think about the rat-rat connection. But it can be found as deep as 3,300 feet, but it spends a lot of its time just like 100 or 200 feet below the surface, you know, in the, it's still like a bottom dweller, but in shallower waters. And following the general corollary that things get freakier the deeper you go into the ocean,

• 35:52Rachel Feltman?

  these guys, in my opinion, are relatively cute for chimeras. I mean, like I've said, I already think chimeras are like ugly cute. But these are, these are more on the spectrum towards like actual mainstream cuties. I would say they're, they're a little closer than average. They have this brown-gray coloring, but they're like very iridescent. They have these white spots. A lot of times you'll see their face as being described as rabbit-like. I don't know that I know what they mean by that, but they do have a very like short little snout, and they have big green eyes. And they have these very cute, like, big spiked fins on their back. Though, fair warning, that spiked fin is venomous.

• 36:34Rachel Feltman?

  It doesn't hurt humans, apparently can cause like a painful wound. But they try to avoid divers. They're not like, they don't want to spike you. But they are potent enough to kill harbor seals that swallow them. So that seems to be the, the main purpose of them is to teach seals that you'll have a bad time if you, if you eat a ratfish. But recent studies have focused on another feature of ratfish heads, which is the teeth that they use for sex, separate from the teeth in their mouths, which they don't use for sex, as far as I know. Male ratfish have this forehead appendage called a tenaculum, which is also the name of a type of forcep, if you, if you care.

• 37:17Rachel Feltman?

  And they use it to hold a female close during sex. The forehead thing is unusual. The grasper part isn't. In my book, Been There, Done That: A Rousing History of Sex, I talk about how our earliest evidence of like penetrative sex as we know it comes from some fossilized fish that were caught like side by side in the act, basically dosey-doing with their graspers clasped. And indeed, the male ratfish has a pelvic grasper to, to help it hold on during sex. But it also has a retractable feature on its forehead that is essentially, as friend of the pod Sabrina Imbler so eloquently put it in their article on the ratfish for Defector,

• 38:02Rachel Feltman?

  "a retractable rod tipped with a chandelier of teeth." Beautiful. Yeah. The, the ocean is full of wonders. And yeah, there are like seven or eight rows of these little teeth. Apparently, the tenaculum, when it's not in use, it retracts into like a little pimple-like nub on their forehead. But yeah, researchers got interested in this appendage, and specifically the teeth on them. Because they're different. When we say teeth, when we look at a tooth-like object, there are different things that can be going on. Because true sharks, actual sharks, as we've talked about before on Reader's Day,

• 38:46Rachel Feltman?

  are covered in dermal denticles, which are sort of skin teeth. If you remember when we had a shark scientist on, she talked about how like there's a wrong way to pet a shark because you can, it's like very sandpapery in one direction and smooth in the other because of those little, little dermal denticles. But those are a different thing. They grow in a different way than the teeth in their mouth. So, you know, the, the kind of first logical assumption might be, ah, this thing that's not in their mouth is some kind of denticle. But other than this weird tooth chandelier that's retractable, ratfish are, are smooth little guys. They do not have any of the sandpapery skin teeth.

• 39:28Rachel Feltman?

  So, yeah, they wanted to analyze the teeth, see what manner of teeth they were. And the other interesting thing about the tenaculum is that, like I said, only males have them and they use them in a very specific way for mating. But both male and female ratfish do grow them, but they only like continue to develop and stick around into adulthood in the males. But in the females, it seems like it basically just stays as like a thing that looks like a pimple. Nice, great. Yeah. So, yeah, that raised the question of like, where did it come from? Why is it there? And also, what kind of teeth is it? And so recently, researchers actually went through the trouble of analyzing this tissue

• 40:11Rachel Feltman?

  and they found that it has dental lamina, which is the structure where new teeth sprout out of in, in the jaw of any animal that has true teeth. So they are mouth teeth. They are not skin teeth. They are mouth teeth. They are on the forehead. They are mouth teeth on the forehead. And so that's weird. It's very, that's weirder than the alternative. And they did some follow-up molecular testing and they were like, yeah, there are mouth-tooth genes in the forehead thinking. So confirmed, mouth teeth on the forehead. And then they also found that this is not like a recent fluke. Cause again, like deep sea, weird, weird stuff happens.

• 40:54Rachel Feltman?

  It would be one thing if this was, ah, just an odd mutation of this one species. They also looked back in the fossil record and they found a related fish from like more than 300 million years ago. And that was the oldest example they found of a tenaculum. It was closer to the animal's jaw compared to the ratfish. So it was, you know, maybe a little less kooky for it to be growing teeth. But it does, you know, it's a, it's a analogous structure. So it does seem pretty clear that the legacy of mouth teeth growing on the outside.

• 41:38Rachel Feltman?

  And being part of these odd appendages is probably hundreds of millions of years old and was useful enough to stick around. And I will say their pelvic claspers have toothy features too, but those are more like denticles. Those are not mouth teeth. They don't have mouth teeth in pelvis. That would just be a bridge too far. But yeah, we, the sort of remaining question is, what was this originally for? Because it's interesting that females seem to have like, you know, for lack of a better term, like a vestigial forehead tooth situation that just doesn't fully develop. And they also have the pelvic

• 42:19Rachel Feltman?

  grasper. So it's not like this was the only way they could have connected for sexual reproduction. So like, that sort of suggests it was once for something else, but I don't know that we'll ever know what it was for. But we do know that they're mouth teeth, and that's really weird. And we may just have to be satisfied with that level of information. I will also say that there is, as part of this recent study, there is like a, an illustration going around that I really think the ratfish has been hard done by in this illustration. Oh, no. Truly, it's just that they look, they look pretty lumpy, and they're, they're

• 43:03Rachel Feltman?

  just colored a like, flat brown. And IRL, they are very like, shimmery, which makes a big difference. And they also, I just think it's, it's not a very flattering picture. I don't think the illustrator did anything wrong. I'm, they are, I'm sure they're excellent at their job, but they really caught the ratfish on a bad day in this illustration. So if that's the first time you saw a ratfish, I encourage you to Google images of them. Because despite being weirdos with retractable tooth graspers for sex, they are kind of beautiful. At least, you know, in the realm of deep sea fish that are weird looking.

• 43:48Rachel Feltman?

  Oh. But yeah, that's my, that's my whole fact. The ratfish, tooth on the head. What, what other mysteries could we uncover in the deep sea? Where do other fish have teeth? We don't even know.

• 44:04Speaker 09

  Mouth teeth. Oh, I hope justice for their bad photo op. That makes me so sad.

• 44:10Rachel Feltman?

  When I, when I saw it in the press release, it was a little bit of a jump scare. I was like, who's, who, which ratfish is that? I don't know her, but yeah. Well, what a rare assortment of facts. Carly, thank you so much for coming on. And would you remind our listeners what your new book is called so they can find it?

• 44:29Speaker 11

  Yeah, thanks again for having me. This was super fun. My book is The Salmon Cannon and the Levitating Frog. And you can find it at your local bookstore, but also at places like Amazon and Barnes and Noble.

• 44:42Rachel Feltman?

  Woo.

• 44:43Rachel Feltman?

  The weirdest thing I learned this week is produced by all of our hosts, including me, Rachel Feltman, along with Jess Bodie, who also serves as our audio engineer and editor extraordinaire. Our theme music is by Billy Cadden. Our logo is by Katie Belloff. If you have questions, suggestions, or weird stories to share, tweet us at weirdest underscore thing. Thanks for listening, weirdos.

• 45:15Speaker 02

  Stonefire Naan is made with real buttermilk and ghee. It's the perfect flatbread for any occasion.

• 45:21Speaker 06

  I put out Stonefire Naan with dips at every dinner party.

• 45:24Speaker 04

  I make naan grilled cheese when my daughter has friends over.

• 45:27Speaker 06

  I use Stonefire Naan to reward the humans who do my bidding. Right. It's perfect for camping trips. Dance for it, feeble mortal. Sorry, is he talking to me or? Dance. Ha, ha, ha, ha, ha.

• 45:41Speaker 02

  From our tradition to yours, Stonefire.

• 45:43Speaker 07

  Together be Naan.

• 45:47Speaker 12

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