Science Friday
Hosted by Flora Lichtman and Ira Flatow
Tales of the amazing capabilities of bats, spiders, and snakes. Plus, a guided tour of some of the world’s spookiest lakes.
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I'm Flora Lixman, and you're listening to Science Friday.
Happy Halloween. On today's podcast, a monster mashup, an ode to three quintessentially creepy creatures: bats, spiders, and snakes.
They're kind of scary, too. I mean, I'll grab one because I'm desperate to collect them for our research, but even I am a little bit reluctant.
Starting with a bat tail that will haunt your nightmares, particularly if you are a robin. The greater nocturnal bat is Europe's largest bat species with a wingspan of about a foot and a half. And here to tell us more is Dr. Elena Tena, National Coordinator for the Spanish Bat Atlas Project. Elena, welcome to Science Friday, and tell us about this bat.
Thank you very much, Flora. Very nice to be here. I really like that we talk about bats here with Halloween because people associate it with fear and these kind of things, but they're not dangerous, and they're impressive and really exciting. And I think it's very cool to talk today about the greater nocturnal bat and what it's doing. This is the first time we just recorded how the greater nocturnal bat capture and eat these birds while they're migrating. And I think the results are really, really impressive.
OK, let's just take a step back in case people missed it. These are bats that eat migrating birds.
Exactly. They're mainly insectivores. Here in Spain and in Europe, all the bats we have, they are insectivores. But in the case of the greater nocturnal bat, sometimes, opportunistically, it can eat some birds during migration. So first of all, we knew that because we found some feathers on the poops of the bat. And the thing is that when we did the DNA of the pieces of the of the bats, we realized that they were eating more than thirty different species of birds. And all of these birds, they were migratory birds.
Oh, you're on a long trip and then a bat just takes you out. So you found feathers in the bat poop. And then your team, do I have this right? Put data recorders on the back of some of these bats?
Yeah, what what we did, it was in a collaboration with the Orfus University in Denmark. What they had, it was these biologers that are very tiny. They have accelerometers to to register movement. It has also an altimeter to register attitude. And it has, what is the most important for us, a microphone that is recording the sounds. So this was the way we could prove how the bat was interacting with the bird. Because we were recording all the audio. And so we have like all the noise of the flapping of the wind beat of the bat. We had the echoes of the bat. And we also have like when the bat was shouting, the echo going forward and backward.
So we could know if if the bat was, for example, intercepting a prey. We had like the echo bat. And even what is most exciting, it was when it was approaching to a prey. We knew if it was successful or not, because we could listen to the chewing, that it was one of the most impressive.
The chewing?
Yeah, the chewing, like you could hear like, you know. So it was very nice like to listen to the bat interacting in in the night, you know. And most of the times, there were insects. So it was a fast chewing, you know, like. But we were thinking, would would we know if a bat is hunting a bird? Would would we listen to the, we would be listening to the bird? Because we didn't know if the bird would be screaming or something like that, you know.
Yeah, so tell me, did this happen? Did you catch on on audio?
Yeah, so this was the most uh for my academic career. It was like the most exciting I have ever done because we were looking like through many data of audios. And suddenly, in one of these audios, we hear like first the whole very strong flapping. And then we suddenly hear like pew. And after a few seconds.
And that's the bird?
Yeah, it was like um eh twenty one distress calls. And after that, like the the bird eh shut eh shut up.
So the chirps stop?
Yeah.
And that and that's it? That's the kill?
And that's it, yeah. So it was just a few seconds. That is the moment that the bat is capturing the bird until the bat is um killing the bird. So after that, we could listen to twenty three minutes of chewing, of mastication.
Wait, twenty three minutes of chewing?
Yeah, exactly. But for me, like the the the most important thing is when we overlap this with the accelerometer and the altimeter. So we could understand better how the bat was doing. Our hypothesis was that the greater nocturnal bats, they were flying out very high to try to detect the birds while they are flying at up in high attitudes. And when we saw uh the attitude, like the bat was flying more than one kilometer high. And suddenly, like in three minutes, it was falling down almost close to the ground. And the bat is chasing the bird for almost three minutes. Yeah, uh like one close to each other, like diving uh downwards vertically till the bat captures the the bird. Almost close to the ground.
And when it captures the bird, the bat is flying normally, like it's not getting down with the weight of the bird. That this is something like for physics, like really a challenge, you know?
Wait, so is it eating on the go for the twenty three minutes it's chewing? Is it in flight?
It is flying normally, completely normally, eating the bird. So that was also like, as we were seeing at first, like these species, the bats are amazing and they're really impressive and we still have many things to know about them.
Dr. Elena Tena is the National Coordinator for the Spanish Bat Atlas Project. Thanks for joining me today and happy Halloween.
Thanks, the same for you too.
Up next in our Fright Fest, arachnids. They're one of the most species diverse groups of creatures on the planet with well over 100,000 species. Compare that to about 6,600 species of mammals. Here to tell us about one arachnid that really belongs in your goodie bag is Dr. Paula Cushing, a senior curator of invertebrate zoology at the Denver Museum of Nature and Science in Denver, Colorado. Paula, welcome to Science Friday.
Hey, thanks so much, Flor. It's good to be on.
You're an expert on the camel spider, which is neither a camel nor a spider.
Correct.
Introduce us to this, this creature.
Scientists are very nerdy people. We like to organize life on Earth into different taxonomic categories, kingdom, phylum, class, order, family, genus, species. And spiders and other arachnids are in the kingdom Monomalia, phylum Arthropoda, class Arachnida. And within that class, there's all these different orders. So spiders are in the order Araniis and camel spiders are in the order Solfugia. So they're a completely different group of arachnids. They do not have venom like spiders do. They do not have silk glands like spiders do. They are very active, cursorial predators, meaning that they're running around on the planet's surface and they run fast, they run long, and they are voracious predators.
When they find an insect, Solfugia will just tear it apart and then they will vomit out digestive enzymes like most arachnids do. And those digestive enzymes break up the tissue of the body and then they slurp it in. But they will eat and eat. And we've, we've read reports of Solfugia that have been kept in captivity that they eat so much that they burst. They basically eat themselves to death. Because I- Think in, in the natural, in the natural environments where they're found, they're, they're very common in xeric, harsh, dry, desert-like habitats where food may not be super abundant. So they're opportunistic predators. And that means that in nature,
you know, if they can get a good meal once a week, they're, they're doing pretty well. If they can get a few insects a night to eat, they're doing pretty well. So if you bring them into the lab and just throw crickets at them, they, I think they're just overwhelmed. They're like, man, I, I have just died and gone to heaven. And then they literally do die.
I can relate. I've been there with a pint, a pint of ice cream.
But sometimes it's hard. It's hard to resist. I, I think I might be able to resist the overeating crickets, but still, you know?
Besides eating themselves to the point of explosion, do they have any other claims to fame?
So with most arachnids, spiders and scorpions and daddy longlegs, they have bursts of activity. They can run in short bursts and then, and then they're sort of running out of oxygen. They have to kind of stop and, and regain their composure to a certain extent. That's not the case with camel spiders. Camel spiders, I had a colleague, Yael Lubin, who in the Negev Desert in Israel, she followed a camel spider for over an hour to see how long it could run without stopping. And she ran out of energy before it did. So the camel spider just kept running. So they have this really interesting metabolic capacity that allows them to just move and move
and move and move and hunt them. They're kind of scary too. I mean, I, I'll grab one because I, I'm desperate to collect them for the, for our research, but even I am a little bit reluctant.
This is the perfect Halloween arachnid to know about. Thank you.
Yes, it is. Spiders are, they're no big deal, but man, solfuges, they scare me even.
A lot of people are spider averse. Why do you think that is?
You know, I've traveled a lot all over the world. And what I think is that in parts of the world where we keep nature at bay, we, we plant non-native grasses in our yards and we really love our asphalt. And, and nature to us is something up in the mountains, something far away, something you go visit, and it's not part of our daily lives. Then any organism that is really distant from human lifestyle, from, from human understanding, is something kind of scary. Because when I travel to places in the world where they may live, where the jungle is coming right up to their homes,
where nature is more a part of the everyday life, they don't bat an eye when I say I study spiders. The spiders and, and the organisms that I study don't seem to elicit that kind of fear response. It's when we distance ourselves from nature that we start to see this fear factor. And I think that's part of it. I think also that on a visceral level, people understand that spiders are predators. And so there's this, this natural reaction to be a little bit wary of a predator, be it a tiny little spider that you could stomp on, or be it a shark, or be it a lion. You know, there's this, oh, these are predators and we need to be careful around these predators.
Dr. Paula Cushing is a senior curator of invertebrate zoology at the Denver Museum of Nature and Science in Denver, Colorado. Thank you, Paula.
You're welcome, Flora. It's great to talk to you.
From eight legs to no legs, next up in our Halloween horror show are snakes. And here to share a tale of slithery delight is Dr. Sarah Ruane, curator of herpetology at the Field Museum in Chicago. Sarah, welcome and tell us about the keelback snake. Thank you so much for having me today, Flora. So this is the genus Reptophis. And these snakes are
Related to the garter snakes and water snakes we have right here in North America. And so they're very common in places they live, which is primarily across Asia, including Russia, especially in Southeast Asia, as well as countries such as Japan. And these snakes, they're sort of unassuming looking. They're maybe two or three feet long, so they're not huge.
Like any villain, you know?
Yeah, exactly, right? Unassuming. You'd have no idea what really lurks behind their unassuming, uh, countenance. What's so cool about these snakes is when people talk about snakes, they often say, oh, is that snake poisonous? What they really mean when they say that is, is that snake venomous? Because the majority of snakes that are medically important to us are snakes that have venom, which means they are injecting it into your circulatory system. They're injecting a substance, a toxin. When people talk about poison, what that really entails is something you ingest. So venom and poison really aren't the same thing. And the majority of snakes that we talk about are going to be venomous. So cobras,
rattlesnakes, all the different kinds of vipers.
Okay, so venomous means they're gonna bite you and get poison in you, that they use this. And poisonous means if you barbecued one, it would make you sick.
Yes, exactly. So the thing about Rob Dofus, about the keelbacks, especially this one called the tiger keelback, is that it is both venomous and it is simultaneously one of the only snakes that is actually poisonous as well.
It's both.
It's both. It's a double.
Double whammy. Yeah.
Exactly, exactly right.
Okay, and, and why do they have this trait?
So what is so cool about this snake isn't just that it is poisonous, it's how did it become poisonous? So what this snake is able to do is it loves to eat frogs and toads. And toads themselves are often poisonous. They produce all these different kinds of toxins, often called bufo toxins. It makes it really hard for a lot of animals to eat them. And so if you think about, oh, we've got now marine or cane toad. Toads potentially in Florida bopping around. People will say, oh, my dog grabbed this toad and now it's foaming at the mouth from chewing on it. And that is what will happen. So eating something that's poisonous like a toad would also give you a pretty bad time.
And it's bad for a lot of species of snakes. A lot of snakes are not able to handle these bufo toxins. Reptopus has evolved to be able to handle this. But not only can they eat these toads, they take the toxins in the toads, the poison, and they sequester them in their own bodies. And this is called kleptotoxicism.
Oh, my God, I love that. I love that word kleptotoxicism. I know some kleptotoxic people.
Right, right. They're feeding off of other people's.
So these snakes, these tiger keelbacks eat these toads. And not only do they get a good meal out of it, they're also getting this extra benefit of taking the toxins from the toad and storing them in these glands on the side of their necks called knuckle glands or nuclo glands, depending on how you want to pronounce it. And these snakes not only then are poisonous for something to eat, these tiger keelbacks can sort of shoot that poison out of the side of their necks.
Stop it.
They're trying to get them, right? And if it gets into someone's eyes, a human's eyes, for example, it's going to cause a little bit of temporary blindness and certainly some unpleasantness.
So they're a triple threat.
Yes, yes. So they can also, it's not just eating them and it's not just what's in their mouth, which is known to occasionally cause fatalities. It's also they can shoot this out of the side of their necks in some really fancy way that is is pretty surprising because this is not something most snakes, I'm not sure actually any other snakes are able to do that particular trick.
This is, this is like my new favorite animal. So thank you.
I know, it's really, really cool. One of the other things I wanted to mention in talking about keelbacks is so this tiger keelback, super, super special. But it turns out that these snakes, a lot of them are eating frogs and toads. There's over thirty species of reptopus. Another species that's found a little bit further south, but India, some other parts of China. Surrounding countries is another one that instead of eating frogs and toads, it primarily eats earthworms, which seems like no big deal. Except that not only does it sometimes eat earthworms, it also sometimes eats firefly larvae, which themselves produce a different kind of toxin that these keelbacks are able
to sequester and use the same way that the tiger keelback uses toad toxins. So there's more than one way to skin a cat when it comes to being a klepto-toxic snake.
You can klepto all around the animal kingdom, it sounds like.
That is right. You don't need to bother producing your own toxins because you can get them from somewhere else for free, simultaneously getting a meal at the same time.
Oh, I love it. Dr. Sarah Ruhan is curator of herpetology at the Field Museum in Chicago. Thanks again for joining me today.
Thank you.
Coming up after the break, a visit to some of the strangest, spookiest lakes on the planet.
A lot of times, lakes are in our backyards and we're so familiar with them that it kind of makes them feel, you know, like a neighbor that has secrets.
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The nerdy nightmare you didn't know you needed: spooky lakes. But what makes a lake spooky, a pond possessed? Here to captain this ghost ship is Gio Rutherford, the creator of the wildly popular and wildly nerdy Spooky Lake Month series on TikTok and Instagram. If you have missed this eddy of the internet, don't worry, we are bringing spooky lakes to your shores. Gio, welcome to Science Friday.
Yes, hello. Thanks for having me.
What makes a lake spooky?
Ooh, I always feel like that's such a good question because I think it's important for people outside of Spooky Lake Month to realize that it's not really about ghosts or ghouls or conspiracy theories or true crime. But Spooky Lakes is actually about science and history, the natural world being spooky all by herself, and environmental disasters.
Give me some examples of spooky criteria.
Oh, for sure. I mean, shipwrecks are very spooky.
Places that are toxic to swim in or dangerous to swim in are spooky. So like a river that can suck you beneath the surface or a mining runoff that has turned the water orange. Those can all qualify as a spooky lake topic.
Love it. And scientifically speaking, why lakes? Do you think lakes are especially spooky?
Well, I started with lakes. I did my entire thesis on the Great Lakes. And so I started with a fascination for lakes. And that process kind of led me to realizing that there's a lot of weird lakes in the world. And I don't think that they've really gotten their love when it comes to social media or even books. I feel like people are just not thinking about lakes. So there was kind of an opening there that I started to fill with Spooky Lake Month. And I
think They're overlooked.
They're definitely underappreciated. And I think that's that lakes are in a lot of ways more spooky than a lot of other water bodies, because they have like this element of the unknown, like you don't know what's beneath the surface, whether something's kind of being preserved at the bottom, and you'll never really know about it. There's something inaccessible about it, kind of similar to the ocean. But I think because a lot of times, lakes are in our backyards, and we're so familiar with them, that it kind of makes them feel, you know, like a neighbor that has secrets.
Which is the ultimate spooky plotline.
For sure.
Well, I think we should dip our feet in. Will you tell us the tale of one of your favorite spookiest lakes? And then maybe I know you rate them too. So maybe we can compare ratings after.
Well, I think that the one to always start with, the one that I do every year, like there's been enough content that I've done this lake every year for Spooky Lake Month, usually on Halloween. And that's Lake Superior, which a lot of us here in North America are familiar with and have a great love for. And that's because we, as people, have been traveling on Lake Superior for centuries. And we have this giant shipping system set up in the Great Lakes because of the St. Lawrence Seaway. And because of that, over 10,000 people have died in Lake Superior. And there's some 400 shipwrecks at the bottom, which might not be the most
That's a lot. No, that's a that seems like a lot of people.
Yeah, it's a lot of people. And I mean, the Great Lakes in general have around 10,000 shipwrecks total. So Lake Superior doesn't have the most of all the shipwrecks. But because she's so cold, And so giant and she's known for these specific November gales where the the water is warm enough that it kind of stirs up storms more aggressively in the more northern part of the Great Lakes. She's just vicious and terrifying and she's taken out ships. And the other thing about the Great Lakes in general is that they, you know, the water is freshwater, so everything freezes and there's ice kind of coating these giant ships. And the waves are much closer together, so they can be really difficult for even these
giant freighters to kind of handle, which is how you end up with shipwrecks like the Edmund Fitzgerald. But my favorite shipwreck to talk about is actually the SS Kamloops, which went down around Isle Royale in the early 1900s. But something else about Lake Superior that most people might not understand is that because it's extremely cold freshwater that doesn't have a lot of bacteria or activity at the bottom, like it's kind of lacking a little bit of oxygen, bodies can be preserved for an extremely long time in the in the bottom of the lake. And so the SS Kamloops has a permanent resident. His name is Old Whitey. He lives in the boiler room.
I'm not sure about that name, but okay.
He's one of the crew members that has never left the ship since he died and his body is perfectly intact because of a chemical reaction called saponification, where the minerals in the cold freshwater interact with human skin and kind of create this coating of soap across the entire body. And that creates this like hard shell that protects protects it from decomposition. And so there are bodies like that across all of Lake Superior, but you can actually go and visit Old Whitey in the SS Kamloops Boiler Room.
You can visit the corpse of this person who worked on this ship that's now covered in a white soapy substance to look like an actual ghost?
Yeah. And if you are swimming in the boiler room with him, then the movement of your fins kind of moves him. And so there's like tails of Old Whitey kind of following you around the boiler room in the SS Kamloops.
Moves him like not just like flutters his soapy hair, but like picks him up.
That's the that's the legend.
Okay, so should we give our ratings?
Yeah, what do you think?
It's like a 10 out of 10. How does it get spookier than that?
Yeah, I definitely agree with you on that one. Lake Superior is always a 10 out of 10 spookies.
Okay, give us one more lake that we can, um, yeah, put in our pocket, put in our goodie bag.
Another lake that I've managed to do multiple videos on because it's just so fantastic and strange is Lake Baikal, which is the oldest and the deepest lake in the world. And just for context, Lake Superior is around 10,000 years old, but Lake Baikal is 25 million years old. It's on a rift valley where the earth is pulling apart. So even though it has 300 rivers like bringing sediment into it, because it's pulling apart, the sediment is just kind of filling in that gap in the earth.
And this is in Russia?
This is in Russia, in like a isolated part of Siberia, which is good because it's an extremely special lake that needs protection. And so it's good that it's kind of isolated. It's by far the deepest freshwater lake in the world. And because of that, it's been around for a long time and it has this unique environment. 80% of the species that live in Lake Baikal are endemic to that lake, which means they can't be found anywhere else. The lake has special sponges and special amphipods. My favorite fish is called the Golem Yanka, which is an oily fish that lives in the deepest parts of the lake and it's cannibalistic.
But I also really love the Baikal Nerpa, which is the world's only exclusively freshwater seal that lives at Lake Baikal. And it's been there for some 2 million years. And no scientists really understand how it got there to be in this freshwater lake in the middle of Siberia.
Wow, a freshwater seal. I didn't even know there was a freshwater seal.
There's a couple more. There's this wonderful little seal in Finland and a seals in Alaska, in Canada. But there's only a few in the world that are kind of considered freshwater.
Well, I feel like the seal deducts spooky points personally because seals are cute. You know, are there other things we should know about this lake before we render a verdict?
Oh, for sure. I mean, I won't get into all the details of all of the amazing Russian history, but they also say that the czar's gold is at the bottom of the lake because of different points in history where there was like war and people had to go across Russia and escape. And in that, it resulted in lots of people kind of ending up dying on the lake and the gold falling to the bottom. Also, if you're wondering, I know you're thinking about this, how would you die in Lake Baikal? You know, we know-
I was thinking about that, exactly. Yeah.
We know how you die in Lake Superior. You're preserved for eternity, but you wouldn't be preserved in Lake Baikal, even though it's incredibly deep and incredibly cold. Instead, you'd be eaten alive by their giant amphipods, or not alive. You'd be eaten dead by the giant amphipods. They would feast on your corpse. They're like the largest freshwater amphipods of the world. They're as big as your hand and there are, you know, millions of them in the lake and they would be very excited if you dropped down to the bottom.
It's like a human cocktail for them.
You should Google a picture of them, the Baikal amphipod. They're so creepy looking. They kind of look like a crab, almost. Like, they're giant. And there are amphipods in other like lakes of the world, but they're much smaller. So the ones here have like evolved to be gigantic and I love them.
Okay. Well, so, okay, so I'm gonna do my calculation now. We've got, on the one hand, gold and a seal. So I, again, I think that deducts points. And then, on the other hand, we have giant crustaceans that are gonna eat you up and a cannibalistic fish. So I, I'm gonna give it a six and a half.
Hmm. We usually give it nine out of 10 on, on-
I'm a tough guy, but I love the seal. You know, it's really, for me, it's all about the seal.
Usually during spooky lake month, I don't focus on the seal. I'm like, don't pay attention to the cute seal, guys. Like, let's talk about being eaten by amphipods.
You know, like we said at the top, lakes don't always get a lot of love, right? Like, they are the neighbor down the street that maybe you don't think too much about. But your channels are huge, like gigantic. Why do you, why do you think they hit with people?
I think it's that fear of the unknown and kind of everyone secretly acknowledging that the scariest things in the world are the things that we don't have any control over and that we don't know anything about. It's kind of that universal understood terror of what's lying beneath the surface.
Gio Rutherford is author of Spooky Lakes: 25 Strange and Mysterious Lakes That Dot Our Planet and creator of spooky lake content on TikTok and Instagram. You can find her at @GioDesoris. Gio, thanks for joining me.
Thank you so much. I loved it.
Before we wrap up this segment, we have a very special message. If you treat Halloween like a competitive sport, like many of us at Science Friday, we have a challenge for you. We are holding a science-themed costume contest. And science-themed can mean a lot of things, from Frankenstein to the Fermi paradox. Go to sciencefriday.com/halloween to enter you, or your kids, or your grandma's costume, into the contest and get all the spooky details. You could win a swag bag. That's sciencefriday.com/halloween.
Okay, I'm gonna dress up as a Golem Yonka fish, I think.
Perfect. Wishing everyone a happy Halloween and many full-size candy bars.
This podcast was produced by Charles Burquist and Rasha Aridi. But a lot of folks helped make this show happen every single week, including... Annie Nero. Jason Rosenberg. John Dankoski. Danielle Johnson. I'm Flora Lichtman. Have a great weekend.
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