Thirst, Part 3

Because there's this interesting thing where after you drink a glass of water when you've been dehydrated, it takes some number of minutes, maybe on the order of tens of minutes, before that water actually gets absorbed through the digestive system and ends up in the blood and makes a difference systemically throughout the body. And yet you still feel that that thirst quenchiness after you have just the first class of water. You're not continue senuous lee chugging for ten

to twenty minutes, at least hopefully not. But to start off today, I wanted to come back to the question of how it is that the body detects the and anticipates the coming changes in your blood and your blood osmolality, which again is the concentration of dissolved substances like mineral salts in your in your body's water content, and how it anticipates those changes to provide you that delicious feeling

of having your thirst quenched by a glass of water. Now, in the previous episodes, we already talked about a few ways that the mouth and the throat might detect the the introduction of water into the body and and sort of sin signals to the brain saying hey, okay, you can put the thirst on hold for now. There there are there are soon coming changes to the body's hydration levels.

And one of the ideas we talked about was the possibility that temperature plays a role, because maybe there there's some evidence that the power of water to cool the mouth and throat sends quenching signals to the brain. And also there was some evidence that rodents were using sour taste receptors in the mouth to detect the presence of water. But Rob, maybe you can sent me straight on this one. I don't think it was clear that triggering the sour

taste receptors actually led to the quenching of thirst. Rather, it seemed to encourage more drinking behavior when the mouse was thirsty. Is that right, Yes, that's my understanding of these findings. But I was actually reading about um a few more studies on exactly this question of of how thirst quenching happens. What is the mechanism that leads to these changes in the brain that tell you, ah, you

are thou art now quenched. So the first thing I wanted to talk about was a study that was reading about a New York Times article from eighteen by Veryy Greenwood called you get thirsty and drink, how does your

brain signal you've had enough? And this is where referring to a paper that I think came up in passing in the previous episode, but it was by Vanyte Augustine at All in Nature called Hierarchical Neural Architecture underlying Thirst regulation, And this research has been looking at exactly this question we just brought up, and they confirmed that, of course, there there is a complex of neurons in the brain that appear to cease activity after a thirsty mouse drinks water.

So there are some neurons that are apparently signaling that generating that thirst motivation state. But then when a roadent takes some water in through the mouth, those neurons shut up, they go quiet. So this would be the neural mechanism to register quenching. But the question is what is the

direct mechanism that that leads to the changes in those neurons. Now, this New York Times article summarizes the findings as explained by the first author on that paper, Vannyte Augustine quote, Intriguingly, what these cells are responding to is not the presence of water itself. Mr Augustine said, The researchers discovered that letting a mouse take big gulps of water would spur the neurons into action, but giving it water in gel form, which had to be chewed before it could be swallowed,

did not. Neither did providing water in tiny two second long SIPs, even when the animals consumed the same total amount of water. In fact, giving the mice oil to drink had just the same effect on the neurons as

gulping water. So that last part is a little gross, But based on this finding, uh, it would kind of imply that a major mechanism leading these thirst neurons to to say, okay, thirst has been quenched, would have something to do with like muscular movements in the throat, the kind of gulping that you do when you're guzzling down a bunch of water really fast. But technically maybe it doesn't even have to be water. It's just any fluid

that you're gulping. I mean, as humans, we don't drink a lot of just straight oil, but we do drink a lot of things that are that are to varying degrees removed from from from you know, from from just a neutral water. Uh So this would make sense, right, But if you if you hydrate yourself in some other ways, so like the examples that you say, consuming water in gel form where you can't like gulp it down, really that still hydrates you, but that apparently does not lead

to this immediate quinching signal in the brain. Similarly with drinking water in very small, isolated SIPs. I guess in those cases you would eventually hydrate yourself and your thirst will eventually go away, But it will be more likely that your body has to just become systemically hydrated before

the thirst goes away. It's not that sudden quinching reward feeling. Now, there was an interesting detail offered here about reasons that the body might need to have this reaction where we turn off thirst very quickly after getting a drink, like why not just wait for your blood osmlality to reach

the ideal level. Well, in previous episodes, we we talked about one reason for this, which is that you know, if you actually did have to wait for your your body's water content to get all leveled out right before your thirst went away, you might you might like kill yourself drinking gallons and gallons of water because you know over the course of the tens of minutes that it takes for this change to to take hold. But there's another reason one of the authors of this paper brings

up that's in this Greenwood article in the Times. Quote, aside from the specter of water intoxication, there are good reasons to drink only the minimum amount necessary when an animal lowers its head to drink, dr Oka speculated, and that's Dr Yukioka. Uh, it's in quite a vulnerable position. Quote. If you double the time of ingestion, that should double the risk of being prey. He said, Uh. And I

thought that was interesting too. I mean, I think it is true that in the natural environment, as we brought up in the previous episode. Going for water is often putting yourself in a vulnerable position, you know, maybe um, exposing yourself from hiding or shelter and sort of turning

your attention away from scanning your surroundings. Yeah. I mean in many cases too, they the access point to the water might not provide much in the way of cover for smaller animals, and then for larger animals there may be you know, bodily positions they have to get into to drink that put them in a greater state of vulnerability, Like I'm thinking of of a drafte for instance. The

draffe of course is a pretty formidable animal. Uh, but but still there's a certain awkwardness present when it actually has to drink water. Sorry, I just started thinking about game or fuel. Um, yeah, this is this says. I have no research to back this up. There's just observational material for me. But I think everyone knows that I enjoy watching the squirrels and um, we have a bird bath outside, uh, near our feeders, and the bird bath is positioned right up against the fence, and the squirrels

drink from that all the time. But I wonder how much I wonder how much of that is that they're able to drink from the bird bath while essentially remaining in a vertical position attached to the to the fence, like they don't have to, you know, go across the clearing. They have I guess, pretty good cover for a squirrel. Those squirrels are bold in other ways that, you know, make you think that they're they're less concerned, or they're or they're in control of the situation as far as

potential predators go. So, if you happen to have sitter squirrels and rover squirrels, your bird bath is positioned in such a way that even the sitter squirrels could could get to it, I guess so. But then, yeah, I don't know. I'd be interested to hear what anyone else out there has observed with their squirrels and drinking water from bird baths and other water water sources. They seem to like one thing versus the other. I don't know. They certainly drink more water than my cat. I'll give

them that well. Anyway. There was another article from the very next year, also in the New York Times, also by Greenwood, covering follow up research from some of the same scientists. So this was published May nineteen just called the Neurobiology of Thirst, and this is summarizing a study published in twenty nineteen in the journal Neuron where the

authors oh again. The first author on this one was Vanite Augustine and it was called Temporally and spatially distinct thirst Satiation Signals UM and the authors here found that the pleasure we get from drinking when thirsty is once again not directly related to hydration. It is a reward pathway separated by both time and space from the body's

hydration and osmolality monitoring mechanisms. And one of the major findings in this paper is that though drinking water is associated with a dopamine release, this this is a typical signal that the brain is expecting a reward. Right you know, things that you want, you want to get and feel good when you get them. That that's often that involves

a dopamine release. But the feeling of rewards in the brain here is apparently not tied to becoming hydrated after being dehydrated, but specifically to the act of drinking water through the mouth. So if you're dehydrated and then you suddenly receive water through an I V or even via a direct injection into the stomach. Your thirst will eventually go away after your body adjusts to the new fluid levels, but you won't get that feeling of reward satisfaction or

the corresponding dopamine release. Those come specifically from the activity of drinking, the gulping of water through the mouth. And picking up on this, I was actually looking at one more paper that had an interesting finding I wanted to mention.

This other one was a little leer. This was from published in Nature called thirst neurons anticipate the homeostatic consequences of eating and drinking, and this is by Zimmerman at All and this study found, among other things, a dual track monitoring system for thirst management, so along the lines

we've already been talking about it. It found that if you take mice and you give them some salt and make them thirsty, drinking water rapidly inhibits neurons in a region of the brain called the sub formical organ or SFO, and that leads to thirst quenching. And of course this is before there is any notable change in blood osmlality. But it also found that if you take these thirsty mice and you give them very salty water and and

the opportunity to drink it. They will drink it, and initially they will gulp it down and it will inhibit the sf O neurons and apparently quench thirst just like the fresh water. But the quenching doesn't last for very long, and they right quote. This initial decline was reversed after

approximately one minute. This indicates that the rapid anticipatory response to drinking has at least two components, an immediate signal that tracks fluid ingestion and a delayed signal that reports on fluid tonicity, possibly generated by an esophageal or gastric osmo sensor. So if you put all of this together, it seems like you've got at least three different time dependent levels of of sort of the body's quench watch uh. And so you put them all together, and you've got

one system that's like are you gulping fluid? If you are, oh that's very good, very good, thou art quenched. But then there's a second system on a slight delay from that one, roughly one minute of delay in mice, It's like, wait a second, what exactly was that you were just gulping. Was that oil or was that super salty water? You know, what, what are you trying to pull? And if it well, if it was not good fresh water, then it will cancel,

cancel the quench and return the thirst. And then finally, I guess there's just the direct blood volume and osmalality monitoring, which is on a much greater delay than the other two. Uh So, first of all, reminder, if anyone else, if anyone is interested in the whole drinking saltwater thing, we did a whole episode on drinking saltwater a while back. You should be able to find that in the archives. Not a good idea was It was one of the

main findings there. But the the other thing, I think, and we've kind of we've kind of touched on this a little bit already, but um, you know, it would be a mistake to think of like, okay, it's just you know, what's drinking water, water in water out. Um, you know, even if you you then acknowledge, okay, well you know the levels have to be just right. But it's it's more than that. It's not like organisms just one day we're like, hey, there's water we can drink

that we should use this to our advantage. Now, like we are of water, so it's like water in am water if all of doubt of things in water, um, etcetera. So it's it makes sense that there would be a more complex relationship with multiple triggers that uh you know

that that we're still trying to understand. Yeah, I mean, as we said at the very beginning, you you are the direct descendant of creatures that long ago lived in the ocean and all of your ancestors, just like you brought the ocean with you onto land, the ocean is now inside your skin. Yes. Oh, and before I wrap up, this last study I mentioned also documents interesting evidence for the the oral cooling mechanism of thirst quenching that I

brought up in the previous episode. So the authors here say that quote we found that are playing cold but not room temperature metal to the oral cavity of awake thirsty mice was sufficient to rapidly inhibit SFO neurons. Thus, temperature dependent modulation of SFO neurons may explain the enigmatic connection between oral cooling and thirst, including why thirsty rodents will avidly lick cold metal and humans report that's sucking

on ice chips rapidly relieves thirst. That's interesting. I hadn't really thought about that with sucking on ice chips, though obviously, I mean that's I think that's something we all do if we have access to iced drinks. Of course. The thing with with ice, of course, is that ice melts

in your mouth as well and actually serves to hydrate you. Right, But that the the cooling effect of having the ice in the mouth may provide a level of of thirst quenching sensation that goes beyond the actual amount of water you're taking in from that ice. This gives me a great idea, um so showrunners and so forth, of the Witcher.

If you're listening, I would love to see a scene where Henry Cavill's uh Witcher character share some wisdom and he's like, sometimes when when I'm thirsty, I just have a good lick of my sword takes you know. It would be gre Haven scene everyway. It's just kind of licking is the blade of his sword. I've never heard this before that apparently thirsty, thirsty rodents will lick cold metal.

But yeah, yeah, but and it's good enough for mice, it's good enough for the Wincher, I think all Gerrold is just gonna that's that's how you cut your tongue, buddy, That's how you cut your tongue. Oh, you know, it reminds me of brom Stoker's Dracula. We have that wonderful scene where Gary Oldman's elderly Dracula licks the blood from the straight razor. See, he was thirsty and he quenched the thirst, but also hopefully the blade was cold enough

that that also had an effect on him. Well, I guess after all these studies we looked at on on on the quenching mechanism, I'm wondering, so the two main different ones have emerged. One is the oral cooling mechanism and the other is the gulping mechanism. You know, the muscular movements in the throat is you're swallowing large amounts of water. Uh. And I'm I guess I'm not sure if these two different explanations are competing or if they're complementary.

Maybe they both play a role in in regulating these thirst neurons in the s f O. I'm not sure than now, given all the things we've discussed about the complexity of thirst, sensations and water acquisition by various organisms.

I thought it might be um be interesting to to look at a couple of examples that, in different ways seem to hijack mechanisms of related to thirst and our relationship with water, not only ours, but also some other organisms for the benefit of a life form, not the life form that is uh that is potentially thirsty, but a life form that is um uh that is hijacking that organism, uh, such as a parasite or a virus.

Oh interesting, so uh. The first one I want to mention here is is one that definitely affects humans, and that is raybies. Now, I imagine I think everyone has heard of rabies, if not buckling, because I'm gonna share a little bit though. This is obviously a topic that you know, we could really bust out if we wanted to and give a full episode treatment. But even if you're just vaguely familiar with rabies, uh, you know, you might not grasp the full danger and horror of this

particular zoonotic viral disease. I think a while back I've read at least somebody making the case that rabies is a contender for like the worst disease known. Yeah, it is pretty horrifying and for a lot of people in UM in the world, particularly and let's let's say the United States, you're lucky enough to to live largely removed from it. Um. I think that the US is sometimes

class of classified as being free of canine rabies. Now there are still cases of canine rabies that pop up, and there are deaths that occur, but but not at the same rate as as other parts of the world where the problem has not been contained as well. So it's uh. Rabies is caused by the virus Lissa virus,

which essentially means rage poison. It's named for the Greek goddess Lissa, the goddess of rage, fury, and rabies Uh, the daughter of Nicks, sprung from the blood of Laurnus um and Uh, and she pops up in different tales, like, for instance, that the urging of hera, she inflicts madness on Heracles, and in some tellings she's also involved in the punishment of the hunter Acteon, who's torn apart by his own mad hunting dogs. And in memory Serves, there

are some interesting treatments of this UH. This latter tale in art I think he he looked at a god or something to that effect. You know, you don't have to do much to get to torn apart by dogs when you're dealing with the Greek pantheon. Yeah. I don't remember all the details, but I think he makes Artemis angry for some reason, and then he's a hunter. But then he's transformed into the quarry like he's trying it is formed into a stag or something, and then his

own hunting dogs hunt thatch. Right, there's some transformation involved there as well. So humans have been exposed to rabies for a very long time. It's um. It's thought that it probably originated in Old world bats and especially flourished during the heyday of of dog domestication. So it is, you know, it is. It is definitely tied to the

canine world. According to the History of Rabies in the Western Hemisphere by Velasco Villa at All, published in Anti Viral Research UM, the earliest record of a disease affecting humans that's consistent with rabies and associated with dogs is found in the Eshnuna cuneiform law tablets in ancient Mesopotamia dating back to the eighteenth through nineteenth centuries b c. Wow, Yeah, and I believe memory served it. It concerns like laws concerning um dogs biting people, like if you you have

a dog and it bites somebody. And of course we have other references to UH to either cases that seem like they could be rabies or we feel pretty strongly are referring to rabies. Aristotle wrote seem to have wrote of it in three thirty b c. Quote dogs suffer from the madness. This causes them to become very irritable,

and all animals they bite become diseased. Democratusts and Hippocrates also wrote of it as well, And there are comparisons to raging dogs in the Iliad that it seems like maybe you're less certain that this is referring, because of course a dog can rage. I guess it doesn't have to be rabbit. But they are also mentions of the dog star Ryan exerting a malignant influence on human health and UH and rabies is just a terrible disease, especially when you really get into what it can do to

an organism and what it can do to human being. UH. To day, it's vaccine preventable, and the vaccines keep improving, but once clinical symptoms appear, it is fatal. According to the World Health Organization, in cases domestic dogs are responsible for spreading it to humans. Again, in the United States, it is effectively we're effectively canine rabies free, though you will still find cases that occur and deaths that occur. So um, it's it's still possible, but it is largely

under control. In other parts of the world it's not the case. And so um, you know, this is all a great reminder why it is important to get your dog rabies vaccine and to also get yourself immunized if you come into contact with the disease, and that time is very important. They're right, Yeah, So that the incubation period for rabies is typically two to three months, but may vary from one week to a year. And I think it depends on like the viral load on you know,

being introduced into your body and some other factors. And then there are two forms of the disease that are possible in humans. So once you know this virus is in your system, uh. One version is paralytic rabies. This only occurs in about twenty of cases, and it consists of gradual muscle paralyzation, coma, and death. It's often misdiagnosed, but again, like twenty of cases, this is what occurs.

The other, however, is the the the the incarnation of of rabies that certainly brings to mind these ideas of strange curses from the gods, you know, the really horrible stuff, and that's furious rabies. Symptoms here include hyperactivity, excitable behavior, hydrophobia, the fear of water, and sometimes aerophobias, well, fear of drafts of fresh air or you know, blasts of air, that sort of thing. And eath occurs in these cases

within a few days due to cardiac arrest. Now, I gotta admit I've always heard uh rabies described as or associated with this idea of hydrophobia, which obviously, yeah, that means fear of water, But I never knew exactly what

to make of that, Like what does that mean in practice? Yeah, because it's you know, when you start thinking about like the things that are a viral infection does like, you know, to to what extent is it about prolonging that virus or or or you know, achieving something and it's um uh, you know, and in it in its cycle um and uh and as you look into it, it's it's really quite interesting. So, um, again, this is the really horrible

fate the furious rabies. If one comes down with this person's behavior and mood is drastically altered, anxiety, hallucinations, confusion, paranoia, terror, and they tend to experience both a profound thirst and a severe in a bill clity to quench that thirst. So what does all this mean? Well, keep in mind

that saliva is central to rabies transmission. Uh. You know, if you think of if you just hear the words rabid dog, the image that probably comes to mind is that of a dog frothing at the mouth, right with the frothing saliva right. And it's generally understood that I guess the saliva is what transmits the disease. Like if you are bitten by a dog that has rabies or by an animal that has rabies, the saliva will transmit it to your blood. Is that a real route of transmission? Yes,

that is the primary route of transmission. Um Bites and scratches are are the most common ways that it is, uh just transmitted. There are other ways, you know, basically any infected fluid um could do it. But those are uncommon compared to bites and scratches, especially when you're you know, think of a dog, think of think of even you know, a bat or or any other organism that would carry rabies.

The bite is the thing, and it's steered in these cases by you know, enhanced aggression and uh and altered behavior and seemingly you know prod. The mouth is primed to transmit the virus by excess infectious frothing saliva. Okay, so much in the same way that respiratory viruses that are spread by aerosols or droplets might tend to cause the infected person to cough or sneeze in order to

further spread themselves to other people. Uh. This disease that is spread often by saliva into blood through bites, uh, it would tend to cause the infected animal too froth in the mouth with a lot of infectious saliva and to be irritable or or aggressive in ways that would lead to biting. Right, And that brings us back to this question of hydrophobia. Like, then then for what reason, you know, seemingly like what role does does the fear uh? And does this terror at the idea of water have

to do with anything UM so humans. This appears to manifest as a kind of panic that sets in when presented with water and difficulty in or inability to drink, like attempts to drink may result in spasms. There is some clinical footage you can find online of of individuals UH that have been diagnosed with rabies attempting to drink water, and I do not I do not very disturbing footage, so I don't recommend seeking it out. But if you find yourself in need of of of the visuals for

this UH, there there is some documentation online. I believe a case in Vietnam is is typically UH typically sided here. Now, does the difficulty with drinking water UH when someone is infected with rabies usually have something to do with difficulty in muscle control, for like swallowing through neurological routes. Yes, yes,

definitely so. And the in the insidious nature of all this, though, is that since the individual is prohibited from drinking water by the infection UM or at least the drinking water becomes excruciatingly difficult UH, saliva production increases. You have hypersalivation and they can't swallow the excess saliva um. And that's and they can't wash away this excess for frau things saliva. So in other words, it primes the victim's mouth to

be this potent transmitter of the virus, especially through a byte. Uh. So it's um. Yeah, it has a real insidious quality to it. But as as horrible as rabies is. Againfortunately there are vaccines that exist, right, Yes, so again all a great reminder you get your pet vaccinated for rabies. And if you come into contact with a with an animal that that has rabies or may have had rabies, Uh, you definitely need to go to a doctor. They can take care of it. You don't want this, this is

this is not an illness you want running its course. Yeah. Now I wanted to share another example though that seems to go or potentially goes in the opposite direction. Uh. Rabies inhibits thirst and and and alters thirst in that direction. But if we look to uh, to to the world of the horsehair worm, we see something that that that may possibly be involved in generating excessive thirst in the host. So uh, this would have to do with parasitoid worms

from the phylum Nematamorpha. Uh. They're known as horsehair worms because their threadlike round worms that resemble the hair of a horse's tail or maine. Now some of you may have seen these before. Um, these are creatures that you'll sometimes find living free in a puddle or stream. I think I saw one once like this while while walking on on on on my mom's property. But you can also see occasionally burst out of the body of a cricket, mantis, beetle,

or other host organism, very much like a xeno morph. Oh. Now, maybe I was seeing something else, but I know I've seen video of something that was like a long, thin worm that was just gradually spooling out of a cricket sexo skeleton to just and it just kept spooling and spooling and spooling, almost like the clown car where you know, fifty clowns get out of a Volkswagen. But it's a worm that seems bigger than the cricket it was inside. Yes,

and it's it's crazy to watch. I have a very vivid memory of being in a junior high band environment and there was a cricket on the floor and somebody in a neighboring section was grossed out by the presence of the cricket, and so they stopped it. And then once they had stopped the cricket, this horsehair worm began emerging from the cricket, which of course only further grows out the individual who'd stopped the cricket. So there's kind

there's some sort of weird, horrific justice in that. Like if you think the crickets grows, will just wait until you see what the encore is. Surely it helped that in band practice that day you were playing Carmena barana. Yeah, if only so. Um. The interesting thing here is that the adults um of this species and in these these these organisms, they are free living in the water, but the larva are are parasitic and grow to adulthood inside the body of an insect. So um, I think you

can all imagine how this probably goes down. Male and female horse hair worms mate and damp soil and fresh water, and then the female lays millions of eggs. These eggs hatch and the tiny larvae insist on vegetation near the water's edge. And then what happens while a cricket or some other suitable host drops by, uh, it ends up eating that larva one way or another. Um either either the you know, like a cricket is eating the grass, or like a mantis is going to eat the larva itself.

And so what happens then is a like a cricket comes along and it it eats the grass that has this uh this larva on it, or if it's a carnivorous mantis, well then it eats a cricket that has already been uh infected by the larva. In either case, the larva winds up inside of another organism. The cyst dissolves, and then the juvenile worm escapes, bores through the gut wall, and starts absorbing nutrients from the host organism. This worm

has a move fast and break things philosophy. It is a it is a disruptor of the internal organs of its host, right, and at this point, it's kind of it's kind of like you can imagine it like a stowaway in the hold of a ship. You know, it's it's rummaging around, it's eating some of the stored food supplies, maybe eating the occasional crew member on that ship um and man, and otherwise also damaging the ship. But it doesn't need if you're stowaway human stow and a ship.

What do you want to do? You want to get to a port somewhere, right and uh And likewise with this worm, it needs to get to water or damp soil in order to uh continue its life cycle. Uh. Now, if if something happens to the cricket, if it's gets stomped in on the floor of a middle school band room, is going to escape, It's going to uh, you know, abandaged ship. But it needs to get to damp soil

or fresh water. So it may be moving fast and breaking things, but it's going to try to do so in such a way that it ends up at a certain place when when the whole thing goes to put right, it needs to steer the host in the right direction. And so this is where we get that bit of parasitic hijacking and action um or at least that's that's one hypothesis of exactly what's going on. That the worm instills a crazed thirst in the host so that it

seeks out water. That's sometimes referred to as the thirst hypothesis m M. An alternate hypothesis states of the worm simply waits till the host finds water on its own and then it jumps out. And it's my understanding that we're really not onecent sure what happens that there. There's some some interesting evidence for for both both hypotheses. Uh. Ed Young and Ted talk Um mentioned that there's research that indicates that this may occur because the organism releases

proteins that alter the crickets brain functionality. Uh so, and and there does seem to be some sort of of It seems like there is a strong case to be made that some sort of hijacking is taking place. And if that's occurring, uh, it may be pushing the animal

towards water via thirst. Okay, so I guess that would mean you might be able to notice this if you had a place where a bunch of insects were getting infected by this parasite, they would be showing a lot of drinking behavior, a lot of water drinking behavior, right. But then again, yeah, there's also the other argument. Well, it's just it's waiting until the water is until it's

until it's drinking. Even even that that would be pretty impressive because it's that like, how does the how does the worm know what's going on inside the darkness of the cricket or the darkness of the mantis that enables the still away to know that there is water or damp soil close at hand. But I was looking at

some of the papers that discussed this. There was a this is of course, this is a much older paper now, but there was a two thousand one study published in the German journal zoo Logishire and zeyger Um that says that the thirst hypothesis has been supported by observations of quote unquote suicidal behavior by infected mantis is in southern France that would seemingly jump into the water and then

immediately outcomes the worm. Um So that would be a case where yeah, like the mantis is not just going to the water, it is to drink and then it bursts out. It's actually jumping in. It's it's it's giving up the ghost. Um So. But I guess with that you still would have to ask your question, at what point is there some hijacking of behavior? Was it the was seeking the water to begin with, or was it something that kicked in when uh, the creature was close

to water. So we're not sure exactly. Uh, you know which way way to go? On this as far as I understand based on the research I was looking at. But it seems like either way you're getting into these interesting Um, you're getting into the relationship between the host organism and water. You know something about its Uh, it's bodily awareness of water or the thirst or desire to be in close proximity to water, and of course that

is ultimately what the parasite wants as well. Right, So the parasite either needs a mechanism of making the host to go drink water or knowing when the host is drinking water. Right in case anybody's worried. Uh, it's my understanding that that occasionally humans end up ingesting these things. But I don't think there's there's ever been any evidence or anything to support the idea that they're capable of

hijacking human behavior. Again, if that is indeed what's happening in the case of crickets and mantiss, well, what happens when humans do ingest them, Um, it's just kind of gross. They could like bombing them up. I was looking there were two Japanese cases reported in due to the accidental ingestation of infected insects. I think in these cases that this has occurred via the consumption of vegetables that had

those insisted larvae on them. You're in, some vegetables seem like they'd be a lot better at hiding a little stowaways than others. Oh yeah, I have this consistent problem with broccoli. I love broccoli. I love cooking with it. But I a number of times I've been like giving it a rinse before I cook it or something, and then I'm like, oh, there's just a bug up in the up in the tree limbs. They're hiding out in a little fork in the in the florets. That's true.

I mean, I guess the it's kind of a the kind of thing about broccoli, right, is that the thing that makes it so delicious, that's it's so great to cook because you get you know, all the the oil or the seasoning. It ends up just getting embedded there in all the little nooks and crannies. It also means they're all these additional places that I guess something could potentially hide, or you could just end up with some dirt or grit in there. Maybe I'm just getting my

broccoli from really buggy sources. I don't know. Sometimes I get like CSA broccoli. That's it's it's really nice, good stuff. But there's just like a there's just a big old bug in there, just just like tarantula is crawling out of it through your kitchen and stuff almost. I mean, it's all just a good reminder, you know, wash washer vegetables everybody, even if you're not sure they need it,

you know, you give them a once over. Why not, right, you'll feel better about it, especially if you're if you're listening to this episode whilst cooking. All right, we're gonna go ahead and close out first part three. What do you think, Joe, do you think we'll be back with Thirst four colon Thirst for Knowledge the Return of Jack Thirst. Yes, yes, yes,

we will be back. I'm sure of it. Yeah, like this Thursday, back this Thurst Today, back Thursday, This Thursday, Thirst Part four, Thirst for More Knowledge, the final chapter on the final chapter only on Stuff to Blow Your Mind or some other topic. I don't know. We'll see how I guess. All right. In the meantime, if you would like to check out other episodes of Stuff to Blow Your Mind, you know where to find them there in the Stuff to Blow Your Mind Podcast feed every

Tuesday and Thursday. Uh, you can find it wherever you get your podcasts. You can also go to stuff to Blow your Mind dot com and that will shoot you over to the I heart listing for this show. Um, I think there's a there's a Yeah, there is a link to our our t shirt store there if you just want to pick up some sort of stuff to blow your mind related design on a shirt or a sticker. Um, we actually have a We may be getting some new

ones in the weeks and months ahead. And I know there are some some designs by listeners that I have that I've added in recent months. So there's a leshy t shirt in there. There's um, there's a kind of psychedelic looking mushroom in there. And uh, let's see what's the other one. Oh yeah, there's the Pandora's box, uh shirt. Those are all wonderful designs, So check those out if you want to. Um, pretty fun. And let's see what else.

Oh yeah, Tuesday and Thursday Core episodes, Wednesday's Artifact, Monday's Listener Mail. Friday is weird House Cinema. That's our kind of satisfied most serious matters and just talk about a strange film huge things. As always to our excellent audio producer Seth Nicholas Johnson. If you would like to get in touch for us with feedback on this episode or any other, to suggest a topic for the future, just to say hello, you can email us at contact at Stuff to Blow Your Mind dot com Stuff to Blow

Your Mind. It's production of I Heart Radio. For more podcasts for my heart Radio, visit the iHeart Radio app, Apple Podcasts, or wherever you listening to your favorite shows that the present point four point four Foo