Nature's Worst Nightmares: The Creepiest Animals on Earth

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Some animals are majestic.

Others...

...should probably stay very, very far away.

In this hilariously horrifying episode of Wildly Curious, Katy Reiss and Laura Fawks Lapole debate the animals they could absolutely live without. From parasites that replace organs to frogs that break their own bones, this episode dives into some of evolution's strangest—and most disturbing—creations. 

Along the way you'll meet:

The Hairy Frog—a frog that breaks its own toe bones and pushes them through its skin to create Wolverine-like claws. 

Human Botflies—parasites that hitchhike on mosquitoes before developing beneath the skin of mammals. 

Brown Marmorated Stink Bugs—the invasive insects that invade homes, destroy crops, and somehow make everything smell worse. 

The Tongue-Eating Louse—the only known parasite that functionally replaces an entire organ by becoming a fish's new tongue. 

Sloths—beloved by millions... and passionately roasted by Laura for nearly every evolutionary decision they've ever made. 

Bobbit Worms—giant ambush predators that hide beneath the sand and explode upward to capture unsuspecting prey—and occasionally hitchhike into home saltwater aquariums. 

Of course, beneath all the jokes is real science. Every one of these bizarre animals evolved these adaptations for a reason, proving once again that evolution doesn't care whether humans think something is creepy—it only cares if it works.

If you love weird animals, parasites, wildlife biology, evolution, gross nature facts, or hilarious science podcasts, this episode is guaranteed to make you laugh... and maybe never look at nature the same way again.

Transcript

SPEAKER_01 0:42

Well, guys, we're gonna talk about animals that we could definitely do without. I should put a disclaimer on this one. I am so sorry for what's about for what I'm about to talk about.

SPEAKER_02 0:54

I Well, and like we've done this episode a long time ago. So we're like, oh, animals we could also do without. Because still there's plenty of animals on planet Earth that we could just do without.

SPEAKER_01 1:06

Yeah. And at least personally. Yeah, right. And this one for me, I I took an unexpected turn for mine. Because this stuff is not- I think I'm gonna take heat. Oh, really? This one I'm not gonna get heat for at all. But I also, this is not something, this is not something that I normally talk about, this kind of stuff. So this should be good. Nature news. Let me think. I had stuff besides there being a red-footed booby in the Chesapeake Bay. I sent Laura that the other day. That's shocking. Shocking.

SPEAKER_02 1:34

A ballista spider they discovered in Australia. Did you see that? No. I'm gonna do a video on it. But about a spider that'll chews. He he like spins this web, an ant comes by and chews on the bottom, and it gets stuck to it and flings, things like trebuchet up towards the spider so they can grab it. New discovered.

SPEAKER_01 1:56

I have a coworker who she just broke some state records in weightlifting, and that was my plan for getting up to the 16th floor. Was the joke was I was like, you could literally just launch me because I'm like 112 pounds and she lifted like 400 pounds, which is no put you. Yeah, that's what we said. I was like, just launch me up there, it's fine. I mean, I mean it's always bird stuff with me. That well, because I should say it's always it's always bird stuff because that's what people send me. So I heavily rely on people sending me nature news because I never remember to, and so that's when I'm normally like, oh, yeah. So animals we could do without. Do you want to go first, Laura? Sure, I do like to go first. Okay. Because I need to have some more wine before I talk about it.

SPEAKER_02 2:37

Insector amphibian. Which do you decide?

SPEAKER_01 2:41

Do do amphibian. Okay. I could do without the hairy frog.

SPEAKER_02 2:47

Oh yeah. Um also known as the horror frog. So look that one up. It's terrifying. Accurately named. Everybody's like, Laura's the frog girl, not this one, but this one creepy. This one and that uh what's the the ones out of out its back. The one in the back. Yeah. Nope, can't even go there. But okay, the natural a little bit of natural history behind this hairy frog. So it's about four inches long, typical frog body, nothing like crazy looking really. Mostly brown with dark colored banding and face markings. It lives in fast-moving water of tropical Central Africa. Um, like all frogs are carnivorous, eating a wide variety of invertebrates, and they're mostly terrestrial except during the breeding season. But here's why it makes me want to vomit.

SPEAKER_01 3:33

Um I I have a feeling that's what this whole thing is, at least for me, everything is like everything I'm gonna vomit. It freaks me out and things I can't handle.

SPEAKER_02 3:43

Well, that's why we could do without them. Yeah. Um, okay, so it has the name hairy frog for a reason. The male grows what looks like hair coming out the sides of its belly and thighs. It's unnatural. Yeah, exactly.

SPEAKER_01 3:55

Frogs aren't meant to be they're not literally not meant to be hairy.

SPEAKER_02 3:59

So whenever you see this, it's it doesn't mean that's when you see it, it's not hair, and you know it's there's something wrong about it. Like it's not fair. If it was a furry frog, okay, maybe I'd be on board with a furry frog. It's not furry.

SPEAKER_01 4:10

Actually, it could be kind of cute if it was like a like a fuzzy, like an actual furry fuzzy, yeah, all over frog.

SPEAKER_02 4:16

Not the case. This is just its sides, and there's something wonky. So it isn't furry, it's horrifying. It isn't actually fur at all. It's really skin growths, like little skin growths, which is also a gross term. That makes sense. Yeah. That contains arteries and veins to carry oxygen. It increases the overall surface area of the frog, allowing it to absorb enough oxygen under the water without needing to come up for air. So basically, it goes back to being a tadpole for a hot second. Like, you know, got the little gillies, and it's like, I'll just be under here. But instead of having face gills and being cute like an axolotl, it's like, I'll grow side hair. Yeah, right.

SPEAKER_01 4:55

It's like evolution just decided let's just move these down here a little bit. Yeah, like under his thighs, just hairy thighs.

SPEAKER_02 5:02

Um, I've I spend most of my life fighting such a thing.

unknown 5:07

All right.

SPEAKER_02 5:07

So the male, and the reason that this happens, why does it not want to come up for air? It's not just lazy, although I guess nobody's ever asked it. The male is responsible for guarding the clutch of eggs in the water. And they're attached underwater, where it's like I said, they live in fast-flowing streams. Yeah. So he's got to actually hunker down and hold on tight and not come up to breathe. Not even for a second, or he's gonna wash away from the eggs.

SPEAKER_01 5:33

I guess we gotta give him at least some props for being a good dad. Right.

SPEAKER_02 5:36

A good dad. Yeah.

SPEAKER_01 5:38

But you don't have to be creepy about it.

SPEAKER_02 5:41

Like totally. Well, right, because why aren't other primarily aquatic frogs hairy? Right? There's plenty of frogs that live underwater because. But it's not just hairy, it's it's skin hairy. It's skin hair. Like, that's worse. They think that it's got to have to do with the oxygen demands of its lifestyle. So I guess these the the primarily aquatic frogs that are just chilling underwater, they don't need skin hair. But the ones that are holding on for dear life in fast flowing water, they're expending a lot of energy and they need skin hair because it's the only way they can breathe.

SPEAKER_00 6:17

They're just like so But also again, evolution is like skin hair.

SPEAKER_01 6:23

We must have skin hair. That's what it goes to.

SPEAKER_02 6:26

Yeah. And thank goodness though, the skin hair only does happen during the breeding season. So it's not hairy all the time. But as if being hairy wasn't bad enough, this psycho breaks its own bones, also giving it the nickname of the Wolverine frog. Okay. So to fight, to fight, it breaks its own bones. So here's what happens. No, it's exactly like wolverine. So inside the toes of this frog, there are these little anchor bones at the tips, and behind that is a sharp bone that um when threatened, the tendons and muscles break it. Break it off, right? And then the detached bone is curved like a cat's claw, so it punctures through the skin. So if you look at pictures, it's just got little claws coming out of its skin. Um, and then I'm so sorry.

SPEAKER_01 7:23

This is gonna be the worst episode we have any.

SPEAKER_02 7:26

Or the bed. This is gonna be good fodder for like lunch table conversation, right? Um so they can actually draw blood, which is why people in Central Africa that hunt them do it with spears and machetes. Because even though it's a it's a four-inch frog that's just jumping out of the water like breaking its own bones because it's no metal. But then once the once the muscles and the tendons relax, it's not that they retract back up in like a cat, they just passively get shoved back in and their bodies heal so they and they can do it again another day. So skin hair during the breeding season, bone claws coming out of their own skin the right other times.

SPEAKER_01 8:10

Can it can it I mean, do they have to ever defend themselves during the breeding season? Like, is it a twofer?

SPEAKER_02 8:17

Probably. I don't know what they do during the breeding season, though. I think it's any time they feel threatened. Like it's just like ready for action. Yeah, breaking its own toes. It's so cool. It's so cool, but so weird. So again, like I'm amazed by this, but I could do without it.

SPEAKER_01 8:34

I'll say Jimmy Christmas.

SPEAKER_00 8:37

I'll say.

SPEAKER_01 8:38

That's so gross. That's so gross. Well, we may or may not have talked about bot flies before, but we're gonna talk to you about it again because we have we actually have a we have a lot of new listeners. Yeah, we have a lot of new listeners that reach out to me. They're like, hey, I'm just finding your podcast. 135 countries, still not in freaking North Dakota, but still not North Dakota. I know. I'm this close to just buying a ticket. I actually looked up prices for tickets just to fly there, just to stop at the airport, listen to a few episodes, then turn around and leave. But it's like $700, so yeah. Yeah, yeah, not worth it. All right, so botflies. So, what's the worst thing a messy can give you? Obviously, not an itchy bite, like I just said, talk about botflies. So, before we start blaming botflies for everything, let's actually talk about a little bit the science. So, the species specifically that I'm talking about today is the human botfly, Dermatobia hominus. Sounds good. Well, I mean it's it's very short word, so you know, I got it. So it's found primarily in tropical regions in Central and South America where it normally is a parasite and it parasitizes mammals, right? Including monkeys, cattle, dogs, and occasionally people. Now, here's the part that I think I'm gonna talk about a little bit of misconceptions here too, in a second. Here and a lot of people think that the adult bot fly is what bites you, but in fact, the adult stage is surprisingly short-lived. Mostly live for about a week or two, and during that time, they're almost entirely focused on one thing finding a mate and reproducing. That's about it. So they don't spend their days buzzing around looking for blood meals like mosquitoes do, right? They don't even spend much time eating at all because adult yeah, just banging it out because that's what they they have to do. But it also explains because they only have a couple weeks, it also explains why they're in such a hurry and almost desperate to do this because they have a week. So all right, here's where things kind of go off the rails, right? Because everybody thinks you either get a mosquito bite or it's yeah, just misconception. So the female buttfly has figured out that chasing mammals around trying to lay eggs on them is a lot of work. So instead, she outsources that work like any smart woman would do. So she catches a mosquito in mid-air, mind you, or sometimes is biting a fly and occasionally even a tick, and she glues anywhere from 10 to 30 eggs onto its abdomen, and then she lets go. That's it.

SPEAKER_02 11:13

So the mosquito then just So you're just mining your, I mean, not that I'm like on the mosquito side, but can you imagine just flying around? Slay their baby onto your belly and just lets you go.

SPEAKER_01 11:26

Permanently permanently slaps their baby on to you and then just flies away. It's like you raise it and then it just dumps like you can't can't do it. But and and again, because it's a mosquito, right? It flies away completely unaware. It has no idea that it's just like a ride. It's just like a a ride share, right? Because that's all it's doing is is an unwilling Uber, let's say.

SPEAKER_02 11:49

And it's another mom. Let's be real, because if it well, she so she also must specifically be targeting female mosquitoes because they're the only ones that suck blood. Yep. So a mom to mom, yeah, she's like it's your blood.

SPEAKER_01 12:01

At least she leaves it with a trusted source, you know, like giving it to anybody. Yeah, right. She gives it to those female mosquitoes. So, but eventually the mosquito lands on a mammal to take its blood meal, maybe a monkey, human, whatever. And this is where the story tends to take off with what most people know is the body heat tells those bot fly eggs they've reached their destination. It's just like a light switch where it's like, oh, this is where I need to jump off at. And the warmth immediately triggers them to hatch, like almost immediately. Tiny larvae then emerge from the eggs and quickly make their way into the skin. Sometimes they enter through the mosquito's bite wound, sometimes through a nearby hair follicle, or even another tiny opening in the skin. So it does not take much. Now, after that, so after it's in there, congratulations, you now have a tenant living in you. And once it's under your skin, right? Once you get once it gets under your skin, it settles in and starts growing. Now, before anybody imagines some horror story that they're eating you alive, it's not really what's happening, but it's still pretty gross. It's disgusting.

SPEAKER_02 13:11

It's I don't care what it's doing in there.

SPEAKER_01 13:13

Right. So the larvae mostly feeds on tissue, fluids, and secretions, not large amounts of blood or anything like that, but still, and it has actually evolved not to seriously harm its host because it it needs it, right? That's yeah, why would it? So, from the bop fly's perspective, a healthy host is much better than nursing a sick one. So it'll stay there for the next four to ten weeks, and during that time, most people develop what looks like a painful insect bite or boil. It may itch, it can drain fluid, and that's where the symptom immediately is like, hey, something, something is wrong here. Because nobody has a bite for that long. Yeah, a bite for that long, and people are like, I can feel it moving. Like not moving, but you know how you have a sensation.

SPEAKER_02 14:00

I would literally cut it open. There's no way I couldn't.

SPEAKER_01 14:02

Me too. I could I couldn't. So the Larva catches a tiny breathing hole in your skin so it can stick one end of its body up to the surface to breathe, which I think is fucking freaking. Sorry, freaking worse. Because it now it installs a breathing hole. So not only do you have this big little reed coming out of a wall. Yeah, right? So it's not visiting anymore, it's making home improvements and setting up shops. It doesn't have a plan to move out anywhere.

SPEAKER_02 14:27

Gross.

SPEAKER_01 14:29

Yep. And so because evolution apparently wanted to make this plan work, the larvae are covered in tiny backward-facing spines. And those little spines act like anchors, helping it stay in place and making it surprisingly difficult to just simply pull out because you you can't. So, and from their perspective, that's pretty pretty darn smart. So eventually that botfly, though, has accomplished everything it came to do. It's grown, it's developed, it's officially overstayed, it's welcome. So one day the fully grown larva simply crawls back out through that le little breathing hole, drops to the ground, buries itself in the soil, and from there it forms a protective case called a pupa and begins transforming into the adult fly. Few weeks later, pops out brand new botfly, ready to find a mate, and here we go all over again. So this is yeah, it's totally disgusting. But despite everything I've just said, botflies are actually pretty remarkable and studied very well. One, it's studied because people don't want to have it in them, but never get botflies. Yeah, right? But one of the reasons why scientists find them so fascinating is because they've evolved this strategy strategy that while it is horrifying and gross to us, it is surprisingly sophisticated. Because a butterfly larva usually they don't want to seriously injure or kill a healthy host. Because again, if your nursery dies, that's bad for business. You're gonna die. So it's evolved to quietly develop under the skin, get what it needs, and leave. Like we notice it because we have intelligence, but on a mammal in the wild, like they're not gonna be itchy. Yeah, it's gonna be itchy, and and that's it. So from an evolutionary standpoint, for them, it is pretty it's pretty pretty smart and pretty keen because it can keep doing it again and again and again, and it continues its life cycle and the genetics of it. And and so for the most part, it's pretty well done. So I wonder how many get infected though after it's come out. I wonder if what do you mean?

SPEAKER_02 16:55

Like oh, like the wound? After it yeah, right. After it comes out and it doesn't care about you as a host anymore. Are you more prone to getting an infection through the exit hole?

SPEAKER_01 17:05

I mean, I I mean I think it would be just as much as it would be any open, you know what I mean? Like open wound.

SPEAKER_02 17:11

Right, any open wound. Yeah. Yeah.

SPEAKER_01 17:13

So I think it would be the same probability there. But yeah, don't look up botflies. Don't Google image that. It's so disgusting. Anyway, botflies. Human bot flies. I'd do without them.

SPEAKER_02 17:24

I don't care how sophisticated.

SPEAKER_01 17:25

No. There there, I cannot see a purpose for something like that in the wild. None. Yeah. Not at all.

SPEAKER_02 17:32

I mean, something else we could surely fill that role. Um, food for something else. I promise you. Exactly. I promise you. Speaking of uh a gross insect, brown marmorated stink bugs. To do with that. Yep. Yep. So again, a little bit of background. They're originally from East Asia, but they came to the United States. So for all of our United States listeners, most of us know what brown what stink bugs are. And we're not even like, if you just say stink bug, this is the one you're picturing, even though there's lots of kinds. Um, came to from East Asia to the US in the mid-90s, and they're now found in 38 states and DC. The adults are shaped like a brown shield, about the size of a dime. And you can tell what type of this type of stink bug because it has a bit of banding, like dark bands around its antenna and around the edges of its abdomen.

SPEAKER_01 18:24

When did you say it got here?

SPEAKER_02 18:26

Mid-90s.

SPEAKER_01 18:27

See, because I don't like I mean, I guess.

SPEAKER_02 18:29

It just didn't really become a big major problem until later.

SPEAKER_01 18:32

Because I remember we were in college and I would go and I went back home and my parents were like, oh, this is the thing. And then in Ohio they started appearing, but then we moved down south, and they you know what I mean? It's almost like we got out of that area before it got big, but that would have been like I don't know, I grew we graduated or I graduated college in what 2011? So okay, okay. I mean it takes a while for bugs to move, right?

SPEAKER_02 18:58

So right, depending on where they got started.

SPEAKER_01 19:00

Yeah.

SPEAKER_02 19:01

The nymphs are also different, like any kind of bug. Nymphs are first red and then turn black and yellow and then turn brown. So they look pretty different, but they're all kind of like shield-shaped.

SPEAKER_01 19:10

Yeah.

SPEAKER_02 19:10

So why they can all just die? Um significant crop damage in the mid-Atlantic, which is where these things are a problem. Where Katie and I are from. So they have mouths that are made for piercing and sucking. Gross. They release a digestive enzyme that liquefies fruit around the mouth part, making it easier to suck up, but leaving these necrotized or dead areas on the fruit.

SPEAKER_01 19:39

Yeah.

SPEAKER_02 19:40

Um, they feed on fruit, making it unmarketable. So just it's hard to sell because it looks gross. And sometimes even unusable for processed products, even like applesauce. You can't use it if it's too much of the apples, just dead. Um they also feed on vegetables and field crops, and they'll hang out on grapes so that when juice and wine are being made, they're gathered up, crushed into a bazillion pieces in the process, and then just destroy perfectly good wine and juice with their nasty little bodies.

SPEAKER_01 20:14

This is why invasive species is so bad, guys. This is why invasive species are soining our wine. Bad, yeah, right? That's that's talk about serious things there. Yeah, coffee and wine, don't mess with it. Us millennial women are coming for you. We will say the pygmy raccoons that we are coming for you, stink bugs. Like, done.

SPEAKER_02 20:35

That needs to be our campaign. 100%. Pygmy raccoons day one, marmore and sink bugs dead day two. Yes, right. So they're ruining our wine. That's terrible. And I can 100% vouch that they taste terrible because I accidentally ate one in chocolate milk once, and it's smell just as bad as it smells.

SPEAKER_01 20:55

Yeah, the smell, I can't even do you go into the smell at all, like what it is for a hot second, yeah. Okay, okay. Because I can't even describe it really.

SPEAKER_02 21:03

Go ahead, continue. Well, so one major crop damage, which is economic and stuff, and then just they're such a freaking pest. Yeah, they don't like the cold, so they decide to just come on in early in the fall, and they can literally enter by hundreds or thousands of stink bugs into your dwelling. That's they seem like they can be found anywhere. They're like in the cracks of your couch, in your window cell sills, like everywhere.

SPEAKER_01 21:30

We would always, my parents, whenever I again, whenever I would go home from Ohio back home, it was every winter the the attic.

SPEAKER_02 21:38

Yeah, because coming in the fall and then it was hanging out in the attic.

SPEAKER_01 21:41

And so every time we'd open up, it's catch the and you don't want to smash them, but you want to catch them. Right. And then, yeah, because it's so oh it smells.

SPEAKER_02 21:48

And then people are like, oh, you know what we should just do? There's so many. Let's just vacuum them up. Don't do it. If you try and suck them up with a vacuum, it will make your vacuum smell. And then the exhaust from the vacuum will pump out that smell. Yeah, and you can't get that you like cannot get rid of it too. And the and what it is is is they're secreting a waxy substance, which makes sense that it doesn't get out of things because wax, you know, it's hard to get out. Wax is so hard to get out of anything since it's hydrophobic. They secrete a waxy substance from their thorax that makes them smell and taste awful. And so the only way to stop them is to just seal up your house because otherwise they're coming in.

SPEAKER_01 22:23

Yeah. Because at this point, uh at this point, they're they're everywhere. They are like up there.

SPEAKER_02 22:30

And because they don't really have natural predators because they're invasive.

SPEAKER_01 22:36

They're invasive, though. It's like nothing.

SPEAKER_02 22:38

And if we're made to eat them in East Asia, things were not made to eat them here.

SPEAKER_01 22:42

Yeah. What I wonder what eats them over there though.

SPEAKER_02 22:44

I don't probably some bird that doesn't have taste buds.

SPEAKER_01 22:47

Yeah, or good smell. Olfactory.

SPEAKER_02 22:50

Yeah, yeah.

SPEAKER_01 22:51

Zero. So no vulgar.

SPEAKER_02 22:52

Definitely some bird. Yeah.

SPEAKER_01 22:53

Yeah, it's gotta be some bird. Alright. I guess if we're talking about senses, here we go onto the next one. Alright, there you go. Laura, let me ask you a question. What's the worst place a parasite could live? I mean for you, what's the worst place?

SPEAKER_02 23:14

Personally.

SPEAKER_01 23:15

We've already talked about under your skin.

SPEAKER_02 23:16

Yeah, yeah, yeah, yeah, yeah. Hmm. I think it'd be a tie between my urethra and my eyeball.

SPEAKER_01 23:24

Okay, close. How about your mouth? Okay.

SPEAKER_02 23:26

Oh okay, that'd be pretty gross too.

SPEAKER_01 23:28

Yep, right? So it's it's yeah, it's pretty it's pretty bad. But this parasite doesn't just live in your mouth, it becomes part of you too.

SPEAKER_00 23:38

Oh stop, is this the fish one?

SPEAKER_01 23:40

Yes. So today. Is that Diggles? Yeah, he was gonna jump up again and claw me again. That wasn't Alora. Do not do that. Do not do that, Chowd. All right, so today we're gonna talk about the tongue-eating louse, an animal that somehow took one look at evolution and was like, you know what? I think I'll become a tongue today. Which is like that's the craziest decision. You could do it better. Yeah, I I think I could do that, John. I could do that. That is the definition of somebody at work. It's like, I could do that. It's like, no, you why? Why do you want to do that? It's like I can do that. No, what? Why? Yeah, nobody. All right, so its scientific name is Simotha Exigua. No clue. But unfortunately, most people just call it the tongue-eating louse because that's a lot easier to say, but it's also a lot grosser. So before you start picturing a terrifying monster, it is actually pretty small. And but to be fair, small is relative because I don't want anything this small in my mouth. Well, never mind. That's true. I mean, so most adults, most adults are only about one to three centimeters long, roughly the size of pretty tiny. That is pretty tiny, roughly the size of your thumbnail. And the females are noticeably larger than the males, but overall, this isn't some giant creature, right? Yeah, but probably if you're a fish, it seems pretty much. If you're a fish, yeah. So it is a crustacean. It is a crustacean, which means it's more closely related to crab, shrimp, and even pill bugs, right? The little rolly pulleys and stuff. So technically, this thing is related to rolly pulleys that you pick up in your backyards, but it's way, way gross and a lot, a lot further distance. So tongue-eating louse are found primarily in the Gulf of California and along parts of the eastern Pacific Ocean where they parasitize a variety of marine fish, particularly snappers and drums. Why those two? Don't know. Um yeah, I don't know. So here's how the whole operation begins. The tongue-eating louse doesn't swim straight into the fish's mouth. That would be easy, right? Instead, it sneaks in through the gills. From there, it crawls its way into the fish's mouth until it reaches the tongue. Right, right, sneaky. And it this lousey. What a lousey. Yeah, that should be the insult anymore. What a louse. Like some backstabber. What a louse. I'm just such a louse you are. So but it goes in through the gills, it hits the tongue, and again, at this point, you're like, okay, another parasite. What's it gonna do? Onto the cheek or something like that. But nope, it it attaches itself to its tongue and begins feeding on the blood that's flowing through it. And over time starting to hurt, no, right? It's so bad. But over time, something incredible, but also deeply disturbing happens. By feeding on the blood supply, this parasite slowly cuts off circulation to the tongue. Without blood, the tongue begins to shrink, it just slowly withers away until eventually it just falls off.

SPEAKER_02 27:06

Not the gangrene tongue.

SPEAKER_01 27:07

No, right? But imagine. What did I just eat? But also, but also it's like I feel like I'm forgetting something, and it's your tongue that you just wake up. What is happening? Because again, that's you think about if you wake up by yourself in the morning, right? The first thing you don't do is start, I don't vocally start talking to myself. And clearly, fish like how they're not gonna know until they go to eat something, right? That is just like gone. So, anyway, so you would think that that would be the end of the story, right? It just cuts off the tongue, and there it goes. But that is where you're wrong. Just because the parasite got rid of the tongue, mission accomplished, that's not true because somehow it just keeps going. Because once that tongue is gone, the tongue-eating louse doesn't leave, it moves into that vacant spot, anchors itself onto the muscles at the base of the mouth, and then it becomes the fish's new tongue, which is so insane.

SPEAKER_02 28:04

Can you imagine being a fish friend and being like your bestie? Just like is like looking back at you.

SPEAKER_01 28:13

Yeah, right. With two little eyes. I'm drawing that picture, like just a um that's too that's crazy.

SPEAKER_02 28:23

There's a movie in pal where this the guy has a tongue that has a tongue, like it's like a little person, and it goes, I'm like, it's a tongue doing that. Now that's all I'm picturing.

SPEAKER_01 28:35

Oh so gross. So now that the parasite has been promoted to tongue, it makes her honestly, it is cool. Okay, take apart all the gross part. It is pretty cool.

SPEAKER_02 28:47

That's how I felt about the what was my first one, the uh the frog, that hairy frog.

SPEAKER_01 28:51

Yeah, it's so disgusting, but it's cool, yeah. So as far as researchers know, the tongue-eating louse is the only known parasite that functionally replaces a whole organ. No other parasite, most of them either take it's it's a mutual relationship, symbiotic relationship. It like takes, gives, and then it either moves on. Some of it, yeah, it does kill it, but it's not, hey, I'm gonna stick around and I'm gonna make myself useful while I'm around. It's not normally like that.

SPEAKER_02 29:19

But I'll also be your tongue, yeah.

SPEAKER_01 29:21

Yeah, right? Why why not? So now, after it is now its tongue, it's been successful, it just stays there, it's its job. The parasite remains attached inside the fish's mouth sometimes for years. It feeds on a combination of blood, mucus, and bits of food that pass through the fish's mouth while the fish just continues to live its life. Which, if you're a fish, you're dismissing your tongue, but you still have the functionality of it.

SPEAKER_02 29:46

So it's kind of like probably don't really have taste buds anyway.

SPEAKER_01 29:49

Yeah. However, we're not done. So because the tongue-eating louse apparently has one more evolutionary plot twist, these parasites all begin life as males. So if a young louse enters a fish's mouth and just a random mouth, and it discovers that there's already an adult female living there, it'll stay male. But if there's no female present, it changes the sex, becomes a female. And there are some fishes that'll do this, but again, sneaks through the gills, destroys the tongue, becomes a tongue, moves in permanently, and if necessary, it'll then change the sex to make sure that it can reproduce. So then are they doing it in the fish's mouth? So, and mate, inside the fish's mouth, the females will carry hundreds of fertilized eggs in a brood pouch, and newly hatched juveniles are released directly into the open water, just like ble, and just one day, all the babies come swimming out your mouth. Oh my gosh, these poor fish. Right? Poor fish. But at the same time, it's lose a tongue, get a tongue. Maybe get to eat some of the eggs, I guess. Yeah, right. Just if as long as you're okay with something banging it out in your mouth. Yeah. Also, you're just there in your mouth, like and you're like, what is what is happening? Like, because you can't. This mouth isn't friend of iniquity. Yeah, right. Just so gross. But despite everything, all of that grossness, scientists absolutely do really find this parasite interesting. Because again, like we said, from an evolutionary standpoint, it is pretty cool. This is another one like the bot fly. I can a hundred percent guarantee we could probably do without this thing. There's no the fish doesn't need a new tongue. It has a tongue, it works perfectly fine. And again, it's not like these louse are the only thing that other fish can eat in the ocean. They tongue down. Yes, right? Like they'll be fine. But it has evolved into keeping its host functioning while benefiting from one of the most unusual places. Because you gotta think too, whenever it reproduces, right? What's safer than in a fish's mouth? Because what's gonna come in there and get you? Nothing. So it's not only making sure that it keeps the functionality to help its host, but it's also protected in there because it's like nothing's gonna come in here and eat me, so I'm gonna bang it out, have my babies in here, and then and then release it. So so anyway, so yeah, scientists do find it pretty interesting. They do study it a good bit because it's the only parasite that we know of that functionally will replace place an organ. So yeah. That there is yeah, the tongue-eating louse. Which I remember learning about this one, but I definitely don't remember Oh no.

SPEAKER_02 32:40

I mean, I just knew about it in passing on some nature doc, but not anything about it. So gross.

unknown 32:48

Okay.

SPEAKER_02 32:48

So here's the one I'm gonna catch heat for. Something I could do without sloths. Okay. I mean some people are like really into sloths, not me. Here's a little bit of natural history.

SPEAKER_01 32:58

This is how I thought about the panda, and we talked about the panda and the things that shouldn't be alive was like panda cool. We knew we were gonna catch heat for it, but yeah. Continue.

SPEAKER_02 33:09

There are seven species across two families. There's three-toed and two-toed. That is just literally the number of super long claws on the front feet. They've been around for 64 million years, so whatever they figured out, they figured it out. They all live within the rainforest. Yeah, they just go for it. All live within the rainforest of Central and South America. They have long arms, shaggy fur, and they're some shade of brown, with super tiny ears, a stubby tail, a small snout. They're anywhere from two to two and a half feet long, eight to seventeen pounds. Two-toed are bigger than three-toed. They're herbivores eating mostly leaves and fruit, and they have insanely slow metabolisms. So that's a sloth. As if you most of you didn't already know that. That's a sloth. That's a sloth in a nutshell. Why they're total creeps. So in 1749, when sloths were first described in scientific literature, I think the person summed it up very well, and they were labeled the lowest form of existence. What an insult. Yeah, absolutely. F those guys. Yeah, right.

SPEAKER_01 34:12

Dang.

SPEAKER_02 34:14

I tend to agree. But no, the looks. Why why I think they're creeps, number one, it's the looks.

SPEAKER_01 34:19

It is three toads have creepy face masks. They they do.

SPEAKER_02 34:23

Because it's always like Yes, and like they've got like yeah, it's just three toads also have two extra neck vertebrae that allow them to turn their heads almost all the way around.

SPEAKER_01 34:36

Okay.

SPEAKER_02 34:36

No mammal has any business doing that.

SPEAKER_01 34:38

To me anyway, the two-toed are definitely cuter than the three-toed. Yes, agree. Yeah, okay.

SPEAKER_02 34:43

And the three-toads are the ones with the extra vertebrae and the masks.

SPEAKER_01 34:45

Oh, interesting. Something about two-toed don't have the extra. I know the head, obviously they don't have the mask, but I didn't know they didn't have the extra vertebrae too.

SPEAKER_02 34:51

Apparently, it's just a three-toed thing.

SPEAKER_01 34:53

Interesting.

SPEAKER_02 34:53

I didn't know something about their round head, lack of ears, and creepy smiles is just a little too close to human for me, but not close enough.

unknown 35:02

Okay.

SPEAKER_02 35:03

Like it's a good thing. That's how I feel about bonobos.

SPEAKER_01 35:05

That's how I feel about bonobos. Like bonobos are just human enough that it freaks me out. Just so yeah, that's like somebody wearing a suit.

SPEAKER_02 35:12

And they have terrifying rotting peg-like teeth for ripping fruit. If any of you have ever seen inside a sloth mouth, they're usually brown.

unknown 35:19

Yeah.

SPEAKER_02 35:19

Two just like and they have slasher claws. They do. No, they're not using them because they're sharp. They're using them to hang and dangle, but they look terrifying. And they move eerily slow, literally one mile per hour. Um, so their excuse for this is that they have terrible eyesight. Their excuse for this.

SPEAKER_01 35:41

Those damn sloths can be moving faster. Just over there making excuses.

SPEAKER_02 35:46

Making excuses for themselves is the fact that they have terrible eyesight, like they're almost completely blind in bright sun, and are in fact colorblind.

SPEAKER_01 35:54

You're like, you're like dogging them so bad. And they're they're blind, they just have a severe handicap, and Laura's over there.

SPEAKER_00 36:00

You guys suck. Like these four songs to say who's gonna be PC that I don't like. They can't even see you insulting them. They're like, who said that? Like, they have no clue. They're creepy. I know.

SPEAKER_02 36:23

And then they they all also move slow because they've evolved to eat leaves, which have very little calories and they take forever to digest. So no energy like dumb pandas. Yes.

SPEAKER_01 36:38

If you guys haven't listened to our episode of things shouldn't be alive. Yeah, things that shouldn't be alive, that is still one of my favorite ones. Talking about the pandas and the colours.

SPEAKER_02 36:47

Talking about animals bragging on animals. That's a good idea.

SPEAKER_01 36:49

Yeah, dude, that was that whole thing. But yes, pandas should should be extinct. The only reason why they're not is because of humans.

SPEAKER_02 36:56

Well, and but here's the thing: unlike dumb pandas and some other leaf-eating animals, most animals that eat leaves just eat a ton of them to make up for the calories, but not sloths, because it takes them so long to digest. Their stomachs get full easily, and they can't eat more before it's digested. So they're full but starving.

unknown 37:16

Yeah.

SPEAKER_02 37:17

Full but starving to death.

SPEAKER_01 37:18

That would be a weird.

SPEAKER_02 37:22

Yeah. The only way they survive is to have an insanely low metabolism. It is 40 to 74% of what it should be for their size of animal. Odd. And they sacrifice their ability to regulate their own body temperature like most warm-blooded animals so that they can have a slow metabolism. So they have giant fluctuations. They've essentially become cold-blooded. Yeah. Because they're so dumb to have evolved eating only leaves. Right. And they're also slow. So slow because they're blind, slow because of bad metabolism metabolisms, and slow because they dropped almost all of their muscle mass because it takes too much energy to maintain muscle. So they're like, they're so frail and feeble.

SPEAKER_01 38:07

I wonder, okay, if you look at it from an evolution standpoint, right? I wonder what they're gonna become next. What besides gelatinous flesh goo? What else are you gonna be? Like, what are you gonna be next? You know what I mean? Because how else could it get worse?

SPEAKER_02 38:22

Giant bounce loths, right? Right. Then they went up into the trees, right?

SPEAKER_01 38:26

And then they got lazy.

SPEAKER_02 38:28

What else are you gonna do? Thank goodness their muscles are arranged in a specific way that actually gives them a lot of stamina for having basically no muscles. And they their their entire strategy and how they've lived 64 million years is that they go so slow that most predators don't even notice them. Notice them, yeah. Lucky predators. Yeah, right.

SPEAKER_01 38:48

That's the only reason why the like pandas are too dumb because they don't even freaking camouflage in.

SPEAKER_02 38:54

And so, like, they usually camouflage, they just go so slow that they're like, nobody sees me. Spees meeting. That's what does when he's trying to be sneaky. So don't get because they're creepy the way they look, don't like it because they move eerily slow, don't like it because they come down only once per week to use the bathroom, which is just disgusting. And when I used to take carousel at the zoo, those nasty things would come down to the floor, pee, pee all over themselves, and then climb back up, just dripping. You know, just nasty. And they turn kind of feral when defending themselves, like they look all innocent and slow, so they have to defend themselves, and then they're like crazy.

SPEAKER_01 39:33

That's how koalas are, because koalas, everybody's oh, sweet, cute, coddle koalas. No, they're actually pretty vicious whenever you get them going.

SPEAKER_02 39:41

I remember us doing that zoo class, and the guy who was in charge of the ambassador animals was like, if there's one animal you don't want to get bit by, it's a sloth because you usually gets infected. Yeah, that's just gonna say the infection of it. Ugh. And I will never forget for the rest of my life that I was cleaning in a room, it was divided by a door with a glass window, and the sloth was out and about, and I'm cleaning, and I turned around, and all I hear is and I look around, and that creeper is upside down with its slasher claws going against the window like a psychopath. I was like a psychopath. I guess it's kind of sad that the pygmy sloth is critically endangered, but you're not gonna hear Laura complaining about it. Yeah, you're not gonna hear me complain. I can do without them.

SPEAKER_01 40:35

Poor sloths, poor sloths.

SPEAKER_02 40:38

Alright, last one.

SPEAKER_01 40:39

Last one. Have you ever walked in the ocean and wondered? I wonder what's underneath the sand. I know Laura hates the ocean, so you don't want to be thinking about that. The next one that I'm gonna be talking about is the Bobbit worm.

SPEAKER_02 40:56

Another parasite?

SPEAKER_01 40:58

Uh, no, no.

SPEAKER_02 40:59

Okay, okay, okay. I was like, okay, we all know we can do without parasites, Katie. No, no, right?

SPEAKER_01 41:04

Listen, there are animals I could do without. All of these I can do without. This one's another one I could do without. This one isn't as well it let's get into it. Okay. The bobbit worm scientific name is Eunice Aphroditis. Close enough. And it's a marine segmented worm called a polychaet. Now, segmented means its body is made up of a lot of repeated sections, right? Almost like someone built a worm out of like Lego pieces, right? Yeah, yeah. It's just body like repeat, repeat, repeat, repeat, repeat. Yep. And each of those little segments have tiny bristles along the sides that help it to crawl, dig, anchor itself in the sand, etc. So they're found primarily throughout the Indo-Pacific, where they spend almost their entire lives buried beneath the sand or the muddy floors. And when I say buried, like almost the entire worm is hidden underground. Usually the only thing sticking out is its head, which somehow I would say, to me anyway, makes the whole situation worse. So if you were looking up one up close, you might actually think it was kind of beautiful because they do look kind of cool. Like many Bobbit worms, they have like an iridescent body shine to it, and it shimmers metallic like greens, purples, blues. Oh yeah, okay. It can be pretty cool. They also have five and ten eye that help them sense what's happening around them. So for the most part, it's a really impressive looking animal. And then you notice the jaws. So those powerful scissor-like jaws are tucked just beneath the sand, waiting patiently, for something to swim just a little too close and who at this point dune worm. No, right? No, it very much so is. Now, the bobot worms that people encounter are nowhere near this size, but some scientists have reported that it can approach 10 feet long, which is nuts.

SPEAKER_00 43:01

Terrifying.

SPEAKER_01 43:02

That is terrifying. Yeah. Because again, like, why what are you doing with 10 feet of worm? Like, why do you need to be how big is your mouth?

SPEAKER_02 43:09

Why would you need to be that long?

SPEAKER_01 43:11

Yeah, teeny teeny terrible.

SPEAKER_02 43:12

Yeah.

SPEAKER_01 43:13

It's a wrestling that's just it's it's gotta be big. I mean, just keeps adding segments. It's just like, let's see how long I can I can get.

SPEAKER_02 43:21

Let's just see.

SPEAKER_01 43:22

Yeah. So here's the thing most predators have to go looking for dinner. Lion chases zebra, shark hunts seals, eagle dives for fish. Bobit worm, like I said, it doesn't chase anything, it doesn't patrol, it just doesn't stalk, it just waits.

SPEAKER_02 43:36

Respect an ambush predator.

SPEAKER_01 43:38

Yeah, right. Patience, something that I don't have. So I mean 100%. Me too. You know, props to the Bobit Worm. To the ambush predators. All right. Props that needs to be on a hat. Also on t-shirts. Yeah. Props to the ambush predators. That's a good one. It's just a shirt with all the ambush predators on it. I'm gonna have dropped.

unknown 44:05

All right.

SPEAKER_01 44:06

I'll think of that one. Um, so in a fraction of a second, all right, the worm explodes out of the sand, grabbing its play prey with a powerful jaw, drags it underneath before the fish even knows what happened. Because it is freakishly fast, which for me is the creepy, terrifying part of it. So the large Bobbit worms have been documented severing smaller fish or even leaving devastating injuries on much larger prey before dragging them underneath the sand, which makes sense because sometimes it just doesn't hit ex for the most part it hits right, but not all the time. So anyway, they can also cause a lot of damage. So for me, the surprising part is as I was researching this, I started thinking, okay, well, at least they're like way out in the ocean, right? Psych wrong. So I'll ruin that feeling for you because one of the most famous and happens quite often enough of Bobit Worm stories doesn't happen in the wild. It happens in people's aquariums. So many saltwater aquariums are built using something called live rock. So they're pieces of natural wreath covered in beneficial bacteria and tiny marine organisms that help create a healthy ecosystem, right? Because saltwater tanks are very tricky.

SPEAKER_02 45:25

Yeah.

SPEAKER_01 45:26

Every now and then, though, that rock arrives with a basically an unexpected passenger, a tiny bobbit worm. Nobody notices. The aquarium gets set up, everything looks great. Weeks go by, sometimes months.

SPEAKER_02 45:39

Start disappearing.

SPEAKER_01 45:40

Sometimes even years. Yep. And then fish start disappearing. All right. So people are like, this is strange. One bite, well, one fish gone, another fish gone. You know, maybe a shrimp, something else just vanishes. Water quality is perfect. You know it's not that. Did it jump out of water? Nope. You can't figure it out. Meanwhile, that whole little monster is just living under your decorations in the tank, minding its own business. And so eventually you catch it. Because again, even if you're cleaning the tank, right, you figure because it has the beneficial bacteria on it, most of the time when you're cleaning saltwater tanks, you pull it out for one thing. Exactly. Yeah. And because you need that healthy bacteria. So it can just hang out in there and just live for as long as it needs to. And in some cases, hobbyists have discovered bobit worms that had been living hidden under their aquariums for years, growing to several feet long before anybody even realizes that they're there. Oh my gosh. So now I just finger gets taken off. Right? So now I was like, okay, well, don't trust sand because you have no idea what the heck is could be a freaking bobbit worm in there. Just crazy. So but why right? So, scientists, why do they love them? Despite the fact that you never want to meet one, bubble worms are pretty cool animals. They're not mindless monsters lurking in the sand. People knock off a lot of worms. They're just like, oh, it's a worm. They're monsters lurking in the sand.

SPEAKER_02 47:07

They're just not mindless.

SPEAKER_01 47:08

Yeah, they're they think they are monsters. They're intentionally coming for you.

SPEAKER_00 47:16

Yeah, yeah, yeah.

SPEAKER_02 47:17

So let's not give them too much cred.

SPEAKER_01 47:19

Yeah, yeah, right. So, but they help keep wreath ecosystems in balance by controlling populations of fish and other animals. And when prey isn't completely consumed, those leftovers become other food for other organisms. And so, unlike the other two, the parasites, this one it it has at least could the ecosystem, I guess we could say, do without it? Probably. However, it's kind of convenient that it goes up and it either eats it, if it doesn't get the whole thing, that it's pieces of it and other things get to eat. So it is pretty cool. And it is Yeah, and it is an ambush predator. It's been around for millions of years, so clearly it's survived doing this. You know, for a reason it's gotten away with it, it's beneficial, so it's kind of kept doing it. So anyway, that is a bobbit worm. But definitely that was the coolest one of the year three. That was cool. Yeah, the other ones are just disgusting, but still bobbit worm, still, I'm like, no thanks. Yeah, yeah, yeah. Could do with could do without it. The ecosystem could probably do without it.

SPEAKER_02 48:29

Exactly. The sloth. The sloth is probably beneficial to the ecosystem. I just personally could do without it. I feel like a lot of food, there's a lot of biomass that a lot of things are eating sloths.

SPEAKER_01 48:40

Yeah, exactly. Yeah, exactly. But yeah, I feel like it would adjust. All right, guys, that's everything for this episode. Next week we continue with another mini episode. Until then, make sure you check us on check us out on Instagram, on Wildly Katie and Laura or Wildly. And then if you can support us on Patreon, it helps keep all of this going so we can keep bringing you all of this content. And so go support us there. And I've been doing and posting long videos on there too of all my birding stuff. So go check that out. Until then, we will talk to you guys next week. Yeah.