Speaker 1: Hey, welcome to Stuff to Blow your Mind. It is Saturday,
Speaker 1: time for another vault. And hey, if you listen last Saturday,
Speaker 1: you know what's up this week. It's Mud Part two,
Speaker 1: So sink in and enjoy more of this exploration. This
Speaker 1: one originally published seven eleven, twenty twenty three.
Speaker 2: Welcome to Stuff to Blow Your Mind, production of iHeartRadio.
Speaker 1: Hey you welcome to Stuff to Blow your Mind. My
Speaker 1: name is Robert.
Speaker 3: Lamb and I'm Joe McCormick, and we're back with part
Speaker 3: two of our series on mud. Now. In the last episode,
Speaker 3: we talked about some sort of definitional constraints on the
Speaker 3: idea of mud, and yes, it is the mud you're
Speaker 3: thinking of, as in wet soil, typically composed of small
Speaker 3: particles of the silt or clay particle size variety. But
Speaker 3: we also talked about mud in the sort of geohistory
Speaker 3: of Earth, in the history of how the continents were
Speaker 3: colonized by early plants and animals terrestrial life, and how
Speaker 3: the presence of mud sort of was sort of driven
Speaker 3: by the presence of plants on Earth's continents, and then
Speaker 3: how the build up of mud on the continents from
Speaker 3: there sort of shaped the way the continents developed. But
Speaker 3: before that, we also talked about a passage in The
Speaker 3: Fairy Queen, which is a late sixteenth century English epic
Speaker 3: poem by the poet Edmund Spencer, in which the author
Speaker 3: talks about his belief that the mud of the Nile,
Speaker 3: and maybe just mud in general, spawns monsters. And I
Speaker 3: knew we were not done with the idea of monsters
Speaker 3: that grow out of mud. Surely there's going to be
Speaker 3: a lot of that going around. And Rob, I think
Speaker 3: you had one as well, didn't you.
Speaker 1: Yeah. I actually looked into this a little bit last
Speaker 1: year because I worked a mud monster into the script
Speaker 1: I wrote for Thirteen Days of Halloween last year, and
Speaker 1: I was looking for inspiration regarding mud monsters, and at
Speaker 1: least at the time, I didn't find as many as
Speaker 1: I thought I would, But I did find one really
Speaker 1: interesting one. This one is a yokai from Japanese traditions,
Speaker 1: and it's known as the Dora Tabo. This name means
Speaker 1: either mud man or rice paddy man, and this yokai
Speaker 1: is generally described and depicted as a humanoid made out
Speaker 1: of mud, or at least a torso of a humanoid
Speaker 1: made out of mud, emerging from the mud of a
Speaker 1: rice patty, grasping with its arms and staring out through
Speaker 1: a single eye in its head as it wails at
Speaker 1: the night.
Speaker 3: It's brutal looking. It's got a kind of mud skeleton
Speaker 3: like you can see the ribs at least.
Speaker 1: Yeah, it's a frightening looking yokai, that's for sure. Of course,
Speaker 1: frightening in yokai doesn't necessarily mean it's going to try
Speaker 1: to kill you, And well that's how it basically breaks
Speaker 1: down in this one. I have a really fun yochai
Speaker 1: book that my son and I read last year. This
Speaker 1: is from Hiroko Yoda and Matt Alt titled Yokai Attack.
Speaker 1: It's a fun little book that has some great illustrations,
Speaker 1: and they point out that the Doro Tabo is not
Speaker 1: generally believed to be dangerous. It cries and frightens those
Speaker 1: who encounter it, but that's about it. Some traditions say
Speaker 1: that it originated as a man who lost his hard
Speaker 1: won farmland and now haunting the rice fields, cries for
Speaker 1: its return in the night, wait.
Speaker 3: The return of the fields. Like as the mud monster,
Speaker 3: he wants to now again be the rightful owner of
Speaker 3: the fields.
Speaker 1: Yeah, yeah, you know, it's like this was my place
Speaker 1: and now you've taken it from me, you know, basically
Speaker 1: haunting one oh one. Right. But the authors here also
Speaker 1: share that the Doro Tabos origins go back at least
Speaker 1: as far as Sakan Toriyama's famous eighteenth century Yokai book
Speaker 1: Tales of Monsters Than and Now, and while it might
Speaker 1: be based on pre existing folk tales, they think it's
Speaker 1: more likely the creation of Toriyama himself. And yeah, it's
Speaker 1: one of these things where it's the frightening spirit here
Speaker 1: loses some of its appeal when it seems that it
Speaker 1: might have been little more than the embodiment of a
Speaker 1: crude sexual metaphor to stick a pole in the rice patty.
Speaker 1: So maybe its origins are less spooky and more just
Speaker 1: kind of skeezy. But still, and the thing is, you
Speaker 1: can see that too if you look at some of
Speaker 1: these illustrations. I mean, it's the monster's appearance is vaguely phallic,
Speaker 1: and the authors point out that Sakan may have been
Speaker 1: referencing brothels that were located north of Edo Castle at
Speaker 1: the time. But whatever the road to get there, the
Speaker 1: result is a pretty cool looking mud monster.
Speaker 3: Now, while we're on the topic of the intersection between
Speaker 3: mud and monsters, there is a movie example that I
Speaker 3: know we have to talk about. It's one not of
Speaker 3: a monster made of mud, but of a hero who
Speaker 3: must defeat a monster by using mud. And you horror
Speaker 3: movie geeks out there, I know you already know the
Speaker 3: one we're thinking of. It occurs in the transition to
Speaker 3: the third act in the original Predator, the movie starring
Speaker 3: Arnold Schwarzenegger and basically every other guy with muscles that
Speaker 3: you could think of in nineteen eighty seven. So, I
Speaker 3: know a lot of you have probably seen this movie,
Speaker 3: but just in case you have, ut I'll explain the
Speaker 3: setup to the mud scene. So the premise of the
Speaker 3: movie is that Arnold Schwarzenegger is leading a group of
Speaker 3: private military contractors on a hit for the CIA in
Speaker 3: the jungle somewhere in Central America. Unbeknownst to them, they
Speaker 3: just happen to be jumping right into the hunting grounds
Speaker 3: of an alien from another planet who likes to come
Speaker 3: to war zones on Earth to hunt humans for sport.
Speaker 1: Yeah, he likes it hot, he likes it violent, and
Speaker 1: that's why he's here.
Speaker 3: That's right, And I always took it to mean that,
Speaker 3: like the predator seeks out war zones because it's like,
Speaker 3: you know, the humans aren't gonna notice as much that
Speaker 3: people are going missing.
Speaker 1: Yeah, there's always a lot of there's already distress, there's
Speaker 1: already people vanishing. It can get in and do its
Speaker 1: thing without having to worry about stirring up the locals
Speaker 1: too much.
Speaker 3: Oh, but it's also because the predator wants to hunt
Speaker 3: like the toughest, like armed humans, Like he's specifically looking
Speaker 3: for humans of the Arnold Schwarzenegger with a machine gun variety.
Speaker 1: Yeah.
Speaker 3: So in this movie, the alien has all kinds of
Speaker 3: technology that gives the alien an advantage over humans. So,
Speaker 3: for example, it can put on a cloaking device that
Speaker 3: makes it nearly invisible to the naked eye. But it
Speaker 3: also has a huge advantage in that instead of just
Speaker 3: seeing the world in the visible spectrum of life like
Speaker 3: we do, it sees in infrared. So the body heat
Speaker 3: of a living organism really pops out of the background,
Speaker 3: making any warm blooded animal easy to track in the forest.
Speaker 3: So by the end of the second act of the movie,
Speaker 3: this alien has trophy hunted Arnold Schwarzenegger's entire team, only
Speaker 3: Arnold has left, and just when you think he's done for,
Speaker 3: he ends up he's running away from the alien. He
Speaker 3: ends up crawling on his belly across a muddy river bank,
Speaker 3: so that his entire body ends up covered in mud.
Speaker 3: And I will note that the mud. I was just
Speaker 3: thinking back on the scene. It does appear to have
Speaker 3: a lot of clay sized particles. I think that's a
Speaker 3: clay rich mud.
Speaker 1: Yeah, it does look look very clay rich.
Speaker 3: But anyway, so yeah, Arnold Swartzenegger ends up total. He's
Speaker 3: totally covered in mud. He's lying there on the river
Speaker 3: bank waiting for the predator to finish him off, and
Speaker 3: to his surprise, suddenly it seems like this alien hunter
Speaker 3: can't see him. The mud has made him invisible to
Speaker 3: the alien. So finally he has an advantage to even
Speaker 3: the playing field against this enemy with overwhelming technology, and
Speaker 3: sort of that sets up the big conflict in the
Speaker 3: third act. It's a great twist. I remember when I
Speaker 3: first saw the movie as a kid, I thought it
Speaker 3: was genius.
Speaker 1: It's pretty great, and it's been very influential because you
Speaker 1: see this either directly referenced in so many films to
Speaker 1: come afterwards, or films will find sort of a new
Speaker 1: way to do the same thing, like our hero accidentally
Speaker 1: finds some sort of protection from from some sort of
Speaker 1: an enemy, or you know, accidentally finds this key strategy
Speaker 1: that they can employ against said enemy.
Speaker 3: Now, while if I remember correctly, I think nobody in
Speaker 3: the movie actually explains how this works. You're just left
Speaker 3: to sort of figure it out for yourself. But the
Speaker 3: way it is presumed to work is that by covering
Speaker 3: his body in mud, Arnold Schwarzenegger here has masked his
Speaker 3: the heat signature of his body because it's now the
Speaker 3: mud is the same temperature as the rest of the environment,
Speaker 3: so he just blends in.
Speaker 1: Yeah, now, this is a scene that's a lot of
Speaker 1: fun to dissect, and maybe maybe almost too fun to dissect,
Speaker 1: Like you can get a little too wrapped up in
Speaker 1: trying to break down whether this will work or not,
Speaker 1: and you have to at the end of the day
Speaker 1: remind yourself, well, we need to experience it through the
Speaker 1: you know, the cinematic excitement of the scene. But still
Speaker 1: there are a couple of key conversations about this. I
Speaker 1: found one that was really interesting that I had not
Speaker 1: run across before from a book titled The Sensory Modes
Speaker 1: of Animal Rhetorics by alex Ey Parrish, and at one
Speaker 1: point in the book, Parish examines this scene and it
Speaker 1: seems to have a mostly high opinion of the sequence.
Speaker 1: He points out that quote, infrared radiation is nearly impossible
Speaker 1: to detect through any amount of water, so the wet
Speaker 1: mud masks Dutch's heat signature. Dutch is the character that
Speaker 1: Arnold plays from the Predator once his high tech mass
Speaker 1: becomes damaged in one of the earlier struggles. I think
Speaker 1: one of the It's been a while since I've seen
Speaker 1: Predator in its entirety, but I think part of it too,
Speaker 1: is that the Predator sees an infrared but it has
Speaker 1: kind of like a it sees everything in infrared, and
Speaker 1: it has some of these technological filters that can throw
Speaker 1: on to sort of refine that a bit.
Speaker 3: Yes, and it may it may have lost some of
Speaker 3: its capabilities in previous combat. Yeah, I'm not sure. Though.
Speaker 1: Now we'll come back to sort of the you know,
Speaker 1: the science of this. I should point out though, that
Speaker 1: I believe Parrish's main interest in this is not really
Speaker 1: about like the direct infrared radiation and thermal science of
Speaker 1: the scenario, but he's he's more interested on this sort
Speaker 1: of this idea of this being an interaction between two
Speaker 1: beings with entirely different sensory understandings of the world. And
Speaker 1: he likes this example because quote Dutch is able to
Speaker 1: think outside his own lived exprience and quickly adapt to
Speaker 1: an alien way of sensing the world. So humans can't
Speaker 1: detect infrared radiation without the aid of technology, and therefore
Speaker 1: most of us are just essentially blind to this realm
Speaker 1: of senses, the direct experience of it, certainly, but also
Speaker 1: perhaps just sort of the idea of it. And know,
Speaker 1: you throw in a very stressful, life threatening situation like
Speaker 1: that depicted in the movie, and you know it adds
Speaker 1: his extra layer to it. So it's kind of neat that. Ultimately,
Speaker 1: the quality that Dutch has that makes them an effective
Speaker 1: hero in the movie is not that he has big
Speaker 1: muscles or he can blow things up. He can do
Speaker 1: all of those things, unless those skills seem to serve
Speaker 1: him well against other humans, But at this point in
Speaker 1: the movie, it is essentially he's essentially about to be killed.
Speaker 1: His only his trick to surviving is being able to
Speaker 1: think outside of the human experience and realize why I'm
Speaker 1: part of its luck too. Obviously that he just happened
Speaker 1: to get so muddy, happened to fall into that water.
Speaker 1: But then the you know, being swift enough to realize, oh,
Speaker 1: this is what is happening. This is what has given
Speaker 1: me the edge.
Speaker 3: Yes, But I guess that brings us back to the
Speaker 3: question of would something like this work in real life, Like,
Speaker 3: I don't know, how would it change your infrared heat
Speaker 3: signature to cover your body in mud?
Speaker 1: Well, as I know a number of you out there
Speaker 1: are familiar with this already because we have I think
Speaker 1: there's a lot of crossover between our listeners and viewers
Speaker 1: of the TV show MythBusters. But yeah, there is an
Speaker 1: episode of MythBusters that busted this myth. They experimented with
Speaker 1: a thermographic camera and they found that it would work,
Speaker 1: but would only work for a very brief amount of
Speaker 1: time until the mud heated up from the human body
Speaker 1: temperature underneath it. Hmm. Okay, And I've seen some other
Speaker 1: analyzes that line up with this as well, arguing that okay,
Speaker 1: it could work, but probably not for as long as
Speaker 1: it seems to work in the movie also based on
Speaker 1: how relative little mud is involved. So I take that
Speaker 1: to mean if Arnold aka dots here had just been
Speaker 1: completely mud monstered himself, like he didn't even look like
Speaker 1: Arnold anymore, you could make a better case for it working.
Speaker 1: But then it would have looked a little silly like.
Speaker 1: Part of the appeal of the scene too, is that
Speaker 1: you know, Arnold's face and muscles are covered with this
Speaker 1: clay like mud slime.
Speaker 3: You can still see the muscles clearly defined, but he
Speaker 3: looks like he's sort of covered in gray paint.
Speaker 1: Yeah, now, Joe, I think you've seen this as well.
Speaker 1: But the twenty twenty two film Prey cleverly adapts this,
Speaker 1: having our hero in this movie, instead of covering themselves
Speaker 1: with mud, they ing just a traditional medicine that it's
Speaker 1: described as it lowers one's body temperature through medicinal means
Speaker 1: and is able to then give the hero the same advantage.
Speaker 3: Over the predator. That was a good twist.
Speaker 1: Yeah, now, I guess you could argue that Dutch was
Speaker 1: also cooling his body temperature because you know, he first
Speaker 1: jumps off a waterfall I think, into this water, then
Speaker 1: he gets covered in the mud. But I can't imagine
Speaker 1: that this on its own would have been enough to
Speaker 1: make a difference, Like it wouldn't have really, It's not
Speaker 1: like he was jumping into like freezing water down there. However,
Speaker 1: this is just occurring to me now. If we think
Speaker 1: of what we see in Predator as sort of the
Speaker 1: myth that spawned by some sort of an event that
Speaker 1: actually happened, I could imagine a situation where Okay, Dutch
Speaker 1: is running for his life, jumps into the cold water,
Speaker 1: crawls through the mud, is covered with the mud, but
Speaker 1: instead of then having a direct confrontation with the predator,
Speaker 1: already has some distance and the predator is not able
Speaker 1: to scan him from a distance in this short time
Speaker 1: it takes for him to then get the rest of
Speaker 1: the way out of range and find a place to hide.
Speaker 3: Yeah, or in the real world scenario just has a
Speaker 3: much thicker coating of mud, like they didn't have to
Speaker 3: be concerned in the real world about making sure you
Speaker 3: could still tell it was arnold.
Speaker 1: Right, Yeah, but then I guess you're doing like there
Speaker 1: are all sorts of complications that arise there too, like
Speaker 1: how much mud can you cake on? Your body without
Speaker 1: it slouching off. How can you move with all that
Speaker 1: mud on your body? So there are limitations there as well,
Speaker 1: I think if memory serves and it could be wrong
Speaker 1: on this, I think in the MythBusters episode they found
Speaker 1: that there were ways to to sort of mask your
Speaker 1: your your heat signature, but you had to, you know,
Speaker 1: use some sort of like a thermal suit to do that.
Speaker 3: Well, I was just thinking, if you if you make
Speaker 3: it so that you're not giving off a visible heat signature,
Speaker 3: wouldn't that just mean you're retaining the heat and therefore
Speaker 3: you would get really hot?
Speaker 1: Hmm. Well, you know, in this we're getting really into
Speaker 1: the more and more into the thermal regulation side of
Speaker 1: the whole scenario, which is fortunate because as we venture
Speaker 1: into the world of real life and animals that often
Speaker 1: cake themselves in mud, wallow and mud and ultimately use
Speaker 1: mud for other things, you don't really find animals covering
Speaker 1: themselves in mud to mask their I our signature. But
Speaker 1: we're going to look at several examples here of animals
Speaker 1: using mud for various purposes in their lives, and I
Speaker 1: think we're going to begin with probably the most notable example,
Speaker 1: the most famous example of a mud loving animal.
Speaker 3: That's right. So, one family of animals whose relationship with
Speaker 3: mud is quite well known is the family Suidy, the
Speaker 3: family containing all the animals commonly known as hogs, pigs, porkers,
Speaker 3: and swine, most notably to humans SEUs domesticus, the common
Speaker 3: domestic pig now pigs, along with plenty of other animals
Speaker 3: like elephants, rhinoceroses, some bovids, etc. Wallow in mud, and
Speaker 3: wallowing is defined as coating the body surface with mud,
Speaker 3: often simply by lying in a pit of muddy water,
Speaker 3: or even sort of rolling around or wiggling in a
Speaker 3: pit of muddy water. But when I thought about it,
Speaker 3: I realized I didn't really know why pigs wallow. My
Speaker 3: best guess was that it had something to do with temperature,
Speaker 3: but I didn't know. So to answer this question, I
Speaker 3: dug up a paper, a paper in an animal behavior
Speaker 3: journal exploring exactly the question of why pigs wallow in mud.
Speaker 3: So the article was by Mark Braca called Review of
Speaker 3: Wallowing in Pigs, Description of the behavior and its motivational
Speaker 3: basis in the journal Applied Animal Behavior Science from the
Speaker 3: year twenty eleven. And there's some interesting motivating context for
Speaker 3: this paper, which is that it was really aimed at
Speaker 3: informing decisions about animal welfare in a domestic context or
Speaker 3: in agriculture, because, of course people keep pigs domestically as
Speaker 3: a farm species and sometimes even as pets, so to
Speaker 3: treat them humanely means understanding what their needs are. And
Speaker 3: it has been widely observed that pigs wallow in mud
Speaker 3: when they can. So is this something that pigs need
Speaker 3: to do for their well being? And if so, why
Speaker 3: do they need to do it?
Speaker 1: So?
Speaker 3: The paper consists of a literature review of the existing
Speaker 3: evidence on why domestic pigs and related species such as
Speaker 3: wild boares coat their bodies in mud. I guess the
Speaker 3: first question is what does this actually look like? Well, like,
Speaker 3: when pigs and wild pigs and bores wallow, what do
Speaker 3: they do? Bracket writes that if a pre existing pool
Speaker 3: of mud is not available, pigs will often make their own.
Speaker 3: They will like dig to make their own wallow, and
Speaker 3: the pit of mud or muddy water where pigs wallow
Speaker 3: the verb is called a wallow the noun so it's
Speaker 3: kind of like how you shower in the shower. They
Speaker 3: wallow in the wallow. When a wallow is available, the
Speaker 3: pig will usually begin by rooting, which means repeatedly pushing
Speaker 3: the snout in and sort of rooting and digging in
Speaker 3: the mud, and then they will enter the mud with
Speaker 3: the four body first, headside first, and then wiggle and
Speaker 3: roll around in the mud, sometimes until much of the
Speaker 3: body or occasionally even the whole body is covered in mud. Now,
Speaker 3: how much of their body they submerge in the mud
Speaker 3: has been observed to correlate somewhat with temperature. According to
Speaker 3: mcgloone in nineteen ninety nine, when the temperature is above freezing,
Speaker 3: pigs will stand in the cool water. When the temperature
Speaker 3: goes up from there, more often they will lie down
Speaker 3: with their utters submerged in the water, and when it's
Speaker 3: even hotter, they will sometimes like roll around and coat
Speaker 3: most or all even of the body in mud. But
Speaker 3: more often the parts of the body they get coated
Speaker 3: in mud are the sides and the underside. The author says,
Speaker 3: if the wallow is deep enough and the temperature is
Speaker 3: high enough, sometimes a sow will submerge its entire body,
Speaker 3: so only the head and the snout is poking out.
Speaker 3: But on hot days it's normal for a pig to
Speaker 3: keep fifty to seventy five percent of its body surface
Speaker 3: covered in mud. Now, some observers do note that pigs
Speaker 3: will exhibit wallowing behavior even in cold weather. That'll come
Speaker 3: back in a bit, but they just they clearly do
Speaker 3: it more often in hot weather. Apparently becomes really prevalent
Speaker 3: around seventeen to twenty one degrees celsius, which is about
Speaker 3: sixty three to seventy degrees fahrenheit. So sometimes a pig
Speaker 3: will stand or lie down in the mud and just
Speaker 3: hang out there. Other times, the pig will get in
Speaker 3: the mud, get a coat of the mud, and then
Speaker 3: leave and let it evaporate as the pig goes about
Speaker 3: its business, maybe returning later to get another coat. Pigs
Speaker 3: are often seen scratching off their coats of dried mud
Speaker 3: against a tree or other scratching post type object. So
Speaker 3: you might get in the mud, get mud all over
Speaker 3: your skin, let the mud dry, and then scratch against
Speaker 3: a tree to get the dried mud off. But what
Speaker 3: purpose biologically does mud wallowing serve. Well, one of the
Speaker 3: most obvious and widely recognized benefits is thermoregulation. As we
Speaker 3: were talking about wallowing in mud, clearly helps pigs keep cool.
Speaker 3: Pigs actually have comparatively little in terms of internal biological
Speaker 3: mechanisms for fighting off the heat, especially compared to some
Speaker 3: other species. They have fewer sweat glands than humans. For instance,
Speaker 3: And there was a paragraph in this paper that actually
Speaker 3: made me feel so much emotion about what it's like
Speaker 3: to be a pig, about how hot it must be
Speaker 3: to be a pig, especially a domestic pig. Do you
Speaker 3: mind if I read this.
Speaker 1: Rob, Yes, let's do so.
Speaker 3: Bracher writes. For several reasons, pigs are prone to overheating.
Speaker 3: Their sweat glands are hardly responsive to elevated temperatures, Subcutaneous
Speaker 3: fat may result in a relatively high insulation value, and
Speaker 3: their barrel shaped body reduced this body surface to body
Speaker 3: mass ratio, and this reduces heat exchange. In addition, compared
Speaker 3: to wild boar, domesticated pigs have shorter snouts and this
Speaker 3: reduces their ability to pant. Furthermore, while domesticated pigs have
Speaker 3: sparse hair cover and larger ears, their ears are not
Speaker 3: very mobile and vascularized as in the case of elephants,
Speaker 3: and their circulatory system has a limited capacity. Finally, pigs
Speaker 3: may be producing considerable amounts of heat eg due to
Speaker 3: muscular activity and feeding, fighting and play, and very high
Speaker 3: production levels, growing up to about one kilogram per pig
Speaker 3: per day, producing up to thirty piglets per sou per year.
Speaker 3: So this just sounds like pigs are busy getting and
Speaker 3: stayin hot. It is hot to be a pig, you
Speaker 3: need to find ways to cool off. So because of
Speaker 3: the convergence of all these limitations and their vulnerability to heat,
Speaker 3: pigs have to supplement their basic internal or anatomical cooling
Speaker 3: capabilities with behavioral ones. And this could in some cases
Speaker 3: be as simple as reducing your movement and seeking out
Speaker 3: shade when the sun is high, But it also includes wallowing.
Speaker 3: So strong is a pig's desire to wallow that in
Speaker 3: some cases, if water and mud are not available in
Speaker 3: the pig's environment, they will lie down against any wet
Speaker 3: surface they can find, or even lie against their own
Speaker 3: feces and urine. Pigs really want to get their skin wet.
Speaker 3: But it's interesting to consider the complexity of how the
Speaker 3: wallowing works, like it's more complex than simply the way
Speaker 3: we would jump in water, say, get in the pool
Speaker 3: to cool off. We all know that it is cooler
Speaker 3: to be in the pool than out of the pool,
Speaker 3: and studies show this is of course true with the
Speaker 3: puddles of mud and pig habitats, even if they're in
Speaker 3: direct sun. But this is not just about the time
Speaker 3: that the pig is physically in the mud in the wallow,
Speaker 3: because if you think of the pool analogy, when your
Speaker 3: skin is wet as you slowly dry off, it takes
Speaker 3: a lot of energy to turn the water clinging to
Speaker 3: your skin into water vapor, and that results in a
Speaker 3: heat transfer from your body to the water as it
Speaker 3: makes that costly phase transition into vapor. So you can
Speaker 3: think of why you feel cold after you get out
Speaker 3: of the shower, even if the shower water was hot.
Speaker 1: Yeah, this is a great point, and with I found
Speaker 1: this with a child. This this period of transition between
Speaker 1: getting out of the swimming pool and going you know,
Speaker 1: back into the house or the room or whatever like
Speaker 1: this is pivotal. Smaller bodies thrown into the mix as well,
Speaker 1: because yeah, they're instantly colder when they get out of
Speaker 1: the pool, but they cannot go back in the pool,
Speaker 1: and you're going to I think we have diminishing returns
Speaker 1: of trying to heat back up in the pool, and
Speaker 1: for you know, again a small bodied child, this is
Speaker 1: gonna be an even more dire situation. They need those towels,
Speaker 1: They need to get to a warm shower somewhere as
Speaker 1: they can warm back up right.
Speaker 3: And this is all so actually the same principle by
Speaker 3: which sweat cools your body, water evaporating from the skin
Speaker 3: makes your body cooler. It's a cooling technique. But another
Speaker 3: thing you might know from getting out of the pool
Speaker 3: is that water drips and evaporates off of the skin
Speaker 3: pretty quickly. So once you leave the pool or the shower,
Speaker 3: whatever it is, the cooling potential of evaporation is relatively
Speaker 3: short lived, probably on the order of just minutes under
Speaker 3: a hot sun. I'm reminded of a time I was
Speaker 3: hiking in a Big Bin National Park in Texas under
Speaker 3: you know, this is a desert environment where like the
Speaker 3: sun is beating down and I remember I was very hot.
Speaker 3: So I took like an icy water bottle that I had,
Speaker 3: and I poured the water just all over myself, like
Speaker 3: on my head and down my back, so my shirt
Speaker 3: was soaked in water. And I remember, so I was like, okay,
Speaker 3: so I'll be good. You know, I'm like wet with
Speaker 3: this icy water. My clothes are wet. I should be
Speaker 3: good for a while, but I don't know how long
Speaker 3: it was, but it felt like within fifteen minutes I
Speaker 3: was bone dry. So being wet and evaporating helps you
Speaker 3: cool off, but it doesn't last that long. Here's the
Speaker 3: genius of mud wallowing. These studies unwallowing show that an
Speaker 3: animal such as a wild pig, coated in mud stays
Speaker 3: wet much longer after getting out of the wallow than
Speaker 3: the same animal coated in water alone. Mud keeps you
Speaker 3: wet longer than water and the mud Essentially, it seems
Speaker 3: like it helps create a matrix for trapping water against
Speaker 3: the skin, which will still provide the benefits of evaporative
Speaker 3: cooling as it dries. But the mud may take hours
Speaker 3: to fully dry into a crust, while water alone is
Speaker 3: gone in minutes. To read from the study here, quote
Speaker 3: wallowing in mud leaves a coat of mud on the
Speaker 3: pig's lateral and ventral surfaces and limbs. This superficial layer
Speaker 3: of caked mud assists in relieving hyperthermia through a vaporation,
Speaker 3: acting as a kind of quote wet suit, helping to
Speaker 3: keep cool in a warm environment. Water in mud on
Speaker 3: the skin of a pig took two hours to evaporate
Speaker 3: compared to fifteen minutes when water alone was used, and
Speaker 3: the evaporation rate was seven hundred to eight hundred grams
Speaker 3: per hour per meter squared. Hence, mud is more effective
Speaker 3: than clean water in temperature control because mud allows the
Speaker 3: evaporation process to continue for a longer time, so for
Speaker 3: cooling the body in hot conditions, mud is an upgrade
Speaker 3: from clean water.
Speaker 1: All right, that makes sense. Yeah, it's the water just
Speaker 1: flows right off you. The water evaporates, but the mud,
Speaker 1: the mud sticks.
Speaker 3: So thermal regulation seems to be the most widely accepted
Speaker 3: explanation for why pigs wallow, and the one with the
Speaker 3: most evidence behind it, but there are a ton of
Speaker 3: other possible or partial explanations that have been offered. And
Speaker 3: one reason for this is that there have been observations
Speaker 3: that while pigs wallow less in cold weather, they still
Speaker 3: wallow some. So if they're doing it even when it's
Speaker 3: like really cold outside, it probably must serve some purpose
Speaker 3: in addition, you know, like some other purpose in addition
Speaker 3: to just avoiding overheating. So what are some of the
Speaker 3: other explanations that have been offered. Well, a number of
Speaker 3: them have to do with various types of grooming in skincare.
Speaker 3: So imagine this pig has ectoparasites on its skin. It
Speaker 3: might have fleas or lice or ticks or something. The
Speaker 3: pig cannot reach back and pick all these parasites off.
Speaker 3: Pig is, unfortunately, by way of evolution, stuck in barrel mode.
Speaker 3: But the pig can wallow and by getting in the
Speaker 3: mud and lying in it, wiggling around, wiggling around, that
Speaker 3: may kill or dislodge some of those parasites. But then
Speaker 3: the benefits continue even after the pig gets up out
Speaker 3: of the mud and the mud dries into a crust.
Speaker 3: The pig can go scratch its body against posts like
Speaker 3: trees or the pin wall or whatever to remove the
Speaker 3: mud crust and probably remove trapped parasites along with it.
Speaker 1: Oh, I'd never thought about that.
Speaker 3: Yeah, So this has been documented as an anti parasite
Speaker 3: behavior in water buffaloes. It is assumed by many to
Speaker 3: serve the same function in pigs, but there's some countervailing
Speaker 3: evidence that. Like the author here sites a study from
Speaker 3: two thousand and five that looked for evidence that wallowing
Speaker 3: reduced parasite loads in wild boar and actually did not
Speaker 3: find any correlation. So the picture on that one seems mixed.
Speaker 3: But there's also it's also been proposed that maybe having
Speaker 3: a layer of mud helps protect pigs from biting insects
Speaker 3: like flo and mosquitoes. That would make sense, and furthermore,
Speaker 3: a layer of mud could also help provide protection against sunburn,
Speaker 3: to which domestic pigs are susceptible. Domestic pigs can get sunburned.
Speaker 3: Being relatively hairless and not having a lot of natural
Speaker 3: skin protection against the sun, they are vulnerable to sunburn.
Speaker 3: Though I was thinking it's interesting that usually the mud
Speaker 3: ends up on the sides and the underside of the pig,
Speaker 3: more so than on the back of the pig, which
Speaker 3: would be the part that's in the most direct sunlight.
Speaker 3: But I don't know few other possible ideas. Maybe there's
Speaker 3: some kind of health benefit not related to heat. Pigs
Speaker 3: have been observed to wallow more when they are suffering
Speaker 3: from disease, and it's also been hypothesized that pigs wallow
Speaker 3: in order to perhaps disinfect wounds because mud in some
Speaker 3: cases can have bacteriocytal properties, but this is another hypothesis
Speaker 3: that was not There was found to be no correlation
Speaker 3: in that same two thousand and five study that found
Speaker 3: no correlation with parasites on wild boar. At least, there
Speaker 3: are other ideas that maybe it has some relationship to
Speaker 3: sexual behavior, such as scent marking or advertising mate fitness,
Speaker 3: but this also seems uncertain. So I'd say the picture
Speaker 3: is definitely plays a role in thermoregulation, and the fact
Speaker 3: that pigs also do it when it's very cold makes
Speaker 3: it seem like maybe it may have some other functions
Speaker 3: as well, but we're less certain about what those are.
Speaker 1: This is all fascinating. Yeah, with pigs and mud, I
Speaker 1: just always I kind of just had the loose understanding
Speaker 1: while they're doing it to cool down. But yeah, it
Speaker 1: sounds like it's sounds like there are more dimensions to that,
Speaker 1: And ultimately, these additional dimensions cast light on many of
Speaker 1: the various other examples of wallowing and mud behavior that
Speaker 1: you see in animals. You know, and we're certainly not
Speaker 1: going to get into all of these examples today, but
Speaker 1: you can see how a number of these explanations can
Speaker 1: and do line up with these other species.
Speaker 3: Right, so you might you know, elephants, rhinoceroses, hippos, water
Speaker 3: buffalo other bovids all engage in wallowing behaviors, and to
Speaker 3: some extent they probably share some of the same biological purposes.
Speaker 3: In fact, there was an interesting passage I did want
Speaker 3: to read from this paper about the evolution of wallowing,
Speaker 3: so the author rights quote. Wallowing, defined widely as covering
Speaker 3: the body surface with a mud like substance, is common
Speaker 3: in mammals such as servids, carnivores and primates. Pigs, however,
Speaker 3: prefer to wallow more specifically in mud, mainly for thermoregulatory
Speaker 3: reasons for cooling, and in this respect it resembles mud
Speaker 3: wallowing seen and other large animals giant tortoises, crocodiles, elephant, seals,
Speaker 3: and in particular in the large hairless mega herbivores such
Speaker 3: as elephants, rhinos, and water buffalo. Pigs probably also descended
Speaker 3: from a large ancestor. By contrast to for example, the horse,
Speaker 3: an odd toed ungulate whose ancestor, the eohippus, was far
Speaker 3: smaller than his descendant. So if I get what the
Speaker 3: author is going for, here it sounds like he's suggesting
Speaker 3: that it's interesting that these species that engage in wallowing
Speaker 3: today tended to be things that had large bodied ancestors. Obviously,
Speaker 3: having a large body means that your cooling needs are
Speaker 3: more acute. And you know, a horse, on the other hand,
Speaker 3: evolves from something with a small body that has less
Speaker 3: acute cooling needs.
Speaker 1: That's fascinating. And yeah, the Galapagos tortoise in particular, I
Speaker 1: mentioned the giant tortoises. Yeah, this is a great example.
Speaker 1: I got to I mean, my family and I got
Speaker 1: to go out and see some of these animals in
Speaker 1: the wild. And there was one particular morning where, yeah,
Speaker 1: a lot of the tortoises had not yet emerged from
Speaker 1: their nightly mud. Some were just coming out, but some
Speaker 1: were still just you know, firmly parked in alone in
Speaker 1: this kind of wallow of mud, and it was going
Speaker 1: to be maybe a little bit the morning was going
Speaker 1: to have to warm up a bit before they started
Speaker 1: coming back out again.
Speaker 3: But of course, the animal uses of mud are by
Speaker 3: no means limited to wallowing and thermoregulation. I mean, in
Speaker 3: a way you can almost think mud is not quite
Speaker 3: like water, but it is close to like water in
Speaker 3: that it is a material and a habitat.
Speaker 1: That's right, and there are various other things that animals
Speaker 1: do with mud that are worth mentioning here. One neat
Speaker 1: place to start is geopogy. This is something that's been
Speaker 1: known of an animals since at least the time of Galen,
Speaker 1: and it's been known that you many animals on occasion
Speaker 1: will eat soil or clay or something that might be
Speaker 1: considered mud. This is one of the issues in talking
Speaker 1: about how animimals use mud, as we fall back into
Speaker 1: the issue of definitions that we discussed in the first episode.
Speaker 1: What's mud, what's not mud? What is more? What would
Speaker 1: you more consider silt and sand and so forth? When
Speaker 1: does mud become dirt? So all of those questions and
Speaker 1: uncertainties remain in effect, but at least in some of
Speaker 1: these cases, animals would be eating something that you might
Speaker 1: define as mud. There are three main reasons for them
Speaker 1: to do this that are recognized. One is to control parasites,
Speaker 1: I believe endo parasites in this regard. Another is for
Speaker 1: mineral contents such as iron, sodium, and magnesium something in
Speaker 1: the mud that they need for their diet. Another factor
Speaker 1: is to help metabolize toxic compounds. You know. They are
Speaker 1: various examples of this in the Animal Kingdom, where at
Speaker 1: least during part of a season, an animal bite might
Speaker 1: be forced to eat some plants that are a little
Speaker 1: rougher on the gut, and the added mud or dirt
Speaker 1: into the system will help sort of balance all of
Speaker 1: that out. Geofogy also factors into some human traditions as well,
Speaker 1: sometimes as a medicinal practice or other times as part
Speaker 1: of a survival dietary substitution practice. Though again we're focusing
Speaker 1: on mud here, and this ultimately goes beyond just mud,
Speaker 1: so it's a stretch, I think, to spend too much
Speaker 1: time on it, but mud is certainly on the table
Speaker 1: in the Animal Kingdom. Now. Another big one, of course,
Speaker 1: is building with mud. Humans, we should note, are famous
Speaker 1: for building with earth and mud is a big part
Speaker 1: of that, and we're going to discuss more about humans
Speaker 1: specifically in the next episode. But of course we're not
Speaker 1: the only animals to make our homes out of mud.
Speaker 1: There are a few key examples to discuss here. I
Speaker 1: think one of the most impressive, though, and one that
Speaker 1: I think a lot of people, if not everyone, out there.
Speaker 1: All some experience with is that of the mud dauber
Speaker 1: or the dirt dauber or the mud wasp.
Speaker 3: As a child, I remember really wondering what the word
Speaker 3: dauber meant.
Speaker 1: Yeah, yeah, I grew up hearing of them as dirt daubers,
Speaker 1: which is kind of a silly name. And also since
Speaker 1: it's like it's it's mud, that's I mean, ultimately it's mud.
Speaker 1: But then the mud dries. That's another one of the
Speaker 1: definitional problems here is that is then mud mud only
Speaker 1: remains mud for a little bit and then it becomes
Speaker 1: like dried mud or dirt and so forth. But anyway, yeah,
Speaker 1: the mud wasp, I'll call them mud the mud wasp
Speaker 1: moving forward, because it sounds a little more serious. These
Speaker 1: are various species of I believe, two different families of
Speaker 1: parasitoid wasps. I definitely encountered these a lot during my
Speaker 1: own childhood. The resulting nests kind of look like imagine
Speaker 1: a like a pan flute composed of cylinders that instead
Speaker 1: of being made out of you know, some sort of
Speaker 1: you know, like metal tubing or bone tubing or wooden
Speaker 1: tubing or what have you. Instead, those are made out
Speaker 1: cylinders of dried mud. And if, when say cleaning out
Speaker 1: an old shed or something, you happen to break some
Speaker 1: of these cylinders open, well, there's an additional level of surprise.
Speaker 1: You might find that they are full of the remains
Speaker 1: of tiny spiders, because while the adults are typically nectar drinkers,
Speaker 1: the young require the meat and the bodies of host
Speaker 1: organisms in the form of spiders, which they cram in
Speaker 1: these cylinders by the dozen. If you've never seen this before,
Speaker 1: I highly recommend looking up some images on your favorite
Speaker 1: image search system because it's grizzly. These chambers are just
Speaker 1: filled with the remains of spiders because they need to
Speaker 1: be in there. The young can hatch in or on
Speaker 1: these spiders and then consume their precious meat. Now an
Speaker 1: interesting wrinkle considering mud wasp nests, however, is that, as
Speaker 1: you may have noticed, while they'll naturally build their nests
Speaker 1: on naturally occurring wood or naturally occurring rock conditions, human
Speaker 1: structures of varying styles and materials often offer great environments
Speaker 1: for them. Particularly, you know, if it's something that's exposed
Speaker 1: to the elements at all, if it's open at all,
Speaker 1: So barns, sheds, this sort of thing. These are often
Speaker 1: significantly encrusted in mud wasp nests, to the point that
Speaker 1: someone may have to come around eventually and scrape them off.
Speaker 1: I think I've even seen them form on window panes,
Speaker 1: that sort of thing. In some cases, they're even building
Speaker 1: their own mud dwellings on human dwellings or creations that
Speaker 1: are made out of mud or stone or earth of
Speaker 1: some sort. And they've been doing this for a very
Speaker 1: long time. In fact, as pointed out by Finch at
Speaker 1: All in a twenty nineteen paper I was looking at
Speaker 1: in coordinary geochronology, the radiocarbon dating of these nests, when
Speaker 1: attached to things like ancient human rock art and relatively
Speaker 1: open rock dwellings, can be incredibly insightful. So we're talking
Speaker 1: like late Plustocene nests here, which which have fossilized. The
Speaker 1: primary innovator of this approach was an Australian geochronologist named
Speaker 1: Richard Burt Roberts Bert being like the nickname you can
Speaker 1: call him Bert apparently, and the hope was that, given
Speaker 1: the wide world distribution of mud wasps, this would become
Speaker 1: something of a standard tool for dating certain sites of
Speaker 1: archaeological interests. I've read some other papers that seem to
Speaker 1: indicate that this didn't quite come to pass. There might
Speaker 1: actually be limited practical value, but it's still pretty interesting
Speaker 1: and apparently maybe in some cases can be incredibly insightful
Speaker 1: when dating something of conditions are just right, all right.
Speaker 1: So that's some added detail on a case of an
Speaker 1: organism using mud that, again I think a lot of
Speaker 1: us are familiar with due to the distribution of mud wasps,
Speaker 1: and also, you know, is a fairly safe thing to
Speaker 1: encounter as a kid. But an example I wasn't familiar
Speaker 1: with concerns fiddler crabs.
Speaker 3: Oh interesting, now, if I recall, fiddler crabs played a
Speaker 3: big role in our series called The Lesser of Two
Speaker 3: Crab Claws about asymmetry and nature.
Speaker 1: Yeah, yeah, and here they are once more, or at
Speaker 1: least two species of fiddler crab. Anyway, So I was
Speaker 1: reading about this in a two thousand and three article
Speaker 1: by Christy at All published in Behavioral Ecology and Sociobiology,
Speaker 1: and they pointed out that you have there are a
Speaker 1: couple of key examples of fiddler crabs that do something
Speaker 1: interesting with the materials that they bring out of their burrows.
Speaker 1: So obviously, one of the things about digging a burrow
Speaker 1: is you got to bring all that dirt up right.
Speaker 1: It's kind of like in the movie The Great Escape.
Speaker 1: What do you do with all that extra dirt from
Speaker 1: digging the tunnels. You can't just stup in one place
Speaker 1: because then the guards will notice. So you've got to
Speaker 1: sneak it around. You've got to put it in the
Speaker 1: cuffs of your pants and secretly deposit it just all
Speaker 1: over the yard.
Speaker 3: Man, how much dirt can you fit in the cuff
Speaker 3: of your pants.
Speaker 1: Well, a little bit at a time, or as much
Speaker 1: as possible at a time to try to avoid detection.
Speaker 1: But you know, the crabs don't have to worry about that.
Speaker 1: So the crabs bring these materials out of the burrow,
Speaker 1: and in a couple of species, you see male fiddler
Speaker 1: crabs essentially to some degree building something out of it
Speaker 1: next to their burrow. For instance, there's the musical fiddler crab.
Speaker 1: This is Leptusa musica, and this one will build what
Speaker 1: it's called a sand hood next to the burrow. So
Speaker 1: this is just like I mean, picture kind of like
Speaker 1: a pile of sand. The image that I found of it,
Speaker 1: it looks kind of like wave, though it's kind of
Speaker 1: like a sail made out of piled sand. It's roughly
Speaker 1: the same height as the crab.
Speaker 3: I think of it as sort of a popped collar
Speaker 3: around the neck hole of the burrow entrance.
Speaker 1: Yeah, yeah, I think that's reasonable. Now you would be
Speaker 1: fair and saying, well, that sounds a lot like sand
Speaker 1: and significantly less like mud guys, But don't worry. There's
Speaker 1: another one, and this is Bebe's Fiddler Crab. Bbe's Fiddler
Speaker 1: Crab sometimes builds mud pillars next to their burrows, and
Speaker 1: this seems to help them attract females for mating. H Now,
Speaker 1: as the authors point out here, this is where it
Speaker 1: it's more interesting is apparently females do seem to prefer
Speaker 1: going over and hanging out near males and burrows that
Speaker 1: have a mud tower, or in the case of the
Speaker 1: musical fiddler Crab, that sand hood. They do seem to
Speaker 1: prefer it, but the practice might not have evolved for
Speaker 1: makee choice. So, in other words, a lot of times
Speaker 1: things like this occur, and we talk about it being
Speaker 1: like a signal of fitness, like saying, look, I mean,
Speaker 1: clearly I'm the one to mate with because look what
Speaker 1: I have throught, you know, look at this thing that
Speaker 1: I can. Look how much sand I can pile up, right,
Speaker 1: And that seems to be kind of like our basic
Speaker 1: way of understanding it. They argue in this paper that
Speaker 1: it may serve These may serve as sensory traps, providing
Speaker 1: shelter for crabs, which crabs, you know, crave to avoid predators.
Speaker 1: If you've ever walked around on the beach, you know
Speaker 1: how this works. The crab doesn't really want to be
Speaker 1: moving out in the open for long. It prefers to
Speaker 1: stick to to crevices and shadows because and of course
Speaker 1: holes and burrows could because there's safety there. And so
Speaker 1: the idea here is that selection pressure emerges out of
Speaker 1: the increased survivability of shade building mail fiddler crabs. So
Speaker 1: the fiddler crabs that have their sand or their mud
Speaker 1: piled in such a way as to allow for a
Speaker 1: little extra shade, a little extra shelter for themselves and
Speaker 1: for females they might be mating with. Uh, these are
Speaker 1: the ones that tend to survive.
Speaker 3: Hmm. Okay, so not just a mate signal, but an
Speaker 3: actual uh actually useful for survival, right right?
Speaker 1: Yeah, and I think they're Their argument, if I'm understanding
Speaker 1: them correctly, is that, yeah, it's it's more about that
Speaker 1: survivability than any kind of signal that they're they're sending
Speaker 1: out there, any kind of fitness signal, though, I mean,
Speaker 1: just as far as you know, I'm looking at these
Speaker 1: pictures and I think I can't stack sand or mud
Speaker 1: that high where it towers over me. I mean this
Speaker 1: one of the of BB's fiddler craft.
Speaker 3: You're thinking I should go mate with that crab.
Speaker 1: Well, no, I mean I just admire. It's like, could
Speaker 1: I stack mud up in a pillar or a column
Speaker 1: that's twice as tall as I am? No, I would
Speaker 1: be crushed by the mud.
Speaker 3: Other factors are obviously hats off to the fiddler crab,
Speaker 3: to the BB crab specifically.
Speaker 1: Yeah, all right. Mud, but of course is also a
Speaker 1: nest building ingredient. Various birds collect mud in addition to
Speaker 1: other elements to build their nest, using the mud as
Speaker 1: kind of a you know.
Speaker 3: Glue or mortar.
Speaker 1: Swallows are the best example of mud use in birds,
Speaker 1: but various birds use mud to some degree. But still,
Speaker 1: if you haven't seen a swallow nest, you should look
Speaker 1: at one. It looks like a muddy mess. This is
Speaker 1: not the bird nest that your kindergarten teacher kept in
Speaker 1: a shoe box to show you.
Speaker 3: Now, this one looks like a real disaster if it
Speaker 3: gets wet.
Speaker 1: I should also, of course mention beavers once more. We
Speaker 1: did a series of episodes on beavers not too long ago.
Speaker 1: Beavers obviously also use mud in their constructions, which are
Speaker 1: made out of wood and mud for the most part. Yeah,
Speaker 1: but I want to get to the best example of
Speaker 1: a mud organism, organism that thrives on it and in it,
Speaker 1: and that is the mud skipper. So in the last episdisode,
Speaker 1: we discussed mud as this intermediate environment that likely played
Speaker 1: a greater role in the evolution of land animals than
Speaker 1: we often consider. Right. It was one of the things
Speaker 1: that I mentioned in the last episode was like you
Speaker 1: think of that that illustration, that simplistic illustration and a
Speaker 1: lot of old science textbooks of the primary organisms coming
Speaker 1: out of the water and taking the land, and it's generally,
Speaker 1: you know, it looks like it's at at your local park,
Speaker 1: or it looks like maybe it's at the beach or something.
Speaker 1: You know, I often think of also if that Treehouse
Speaker 1: of Horror episode where the creature crawls out of the
Speaker 1: water and Homer Simpson sets on it or steps on it.
Speaker 1: Africat which one it is.
Speaker 3: I'm thinking of a fish with human feet like that,
Speaker 3: like Julius Caesar's horse in that drawing.
Speaker 1: Yeah, but like we discussed like these kind of these
Speaker 1: these muddy environments, muddy waters and muddy shores and mud flats,
Speaker 1: they were. They were probably a lot more important than
Speaker 1: we often give them credit. And even today, when you
Speaker 1: consider the mud flats found in coastal wetlands around the world,
Speaker 1: you'll find vital ecosystems that are home to various specialized organisms.
Speaker 1: And yeah, the mud skipper is a mud specialist. You
Speaker 1: may like to go mudding, but the mud skipper lives
Speaker 1: in the mud. This is the mud skipper's world.
Speaker 3: You're in my world now. Yeah.
Speaker 1: So there are twenty three extended species of mud skipper.
Speaker 1: They're members of the vast Gabba daet family. More than
Speaker 1: two thousand species and more than two hundred of gen era.
Speaker 1: I've seen that count lower as well, but it's still
Speaker 1: a lot. There are a lot of Gobi's.
Speaker 3: In the world.
Speaker 1: But Gobi's you know what I'm talking about. Most of
Speaker 1: you probably do Gobi's. They have kind of a telltale
Speaker 1: look right their heads, their overall morphology, they look like Gobi's.
Speaker 1: There's kind of I don't know how else to explain it.
Speaker 3: They all kind of look like they're saying, hey, guys,
Speaker 3: what's going on? Exactly?
Speaker 1: Yeah, there's a I think there's some Gobies on SpongeBob Like.
Speaker 1: They're very Spongebobby in there. Parents. Now they're fifteen gen
Speaker 1: era of air breathing Goby's. But the mud skippers here
Speaker 1: in particular, belong to the genus Periophthalmus, and they have
Speaker 1: several defining features of note here that aid them in
Speaker 1: their muddy habitat. So, first of all, they have fused
Speaker 1: pelvic fins which form a disc shaped sucker, which aid
Speaker 1: them by allowing them to sort of attach to surfaces.
Speaker 1: They can use these to aid themselves in climbing rocks
Speaker 1: and even trees. Namely, now we're talking about mangroves here,
Speaker 1: but we're talking about their roots, their trunks, their lower branches.
Speaker 1: So definitely a case of a fish that can climb
Speaker 1: a tree.
Speaker 3: Wouldn't have thought that.
Speaker 1: But of course this is not the only gobi that
Speaker 1: excels at climbing. There is also a gobi that you
Speaker 1: will find in Hawaii if you visit certain waterfalls that
Speaker 1: I don't know if you'll get to see one. I
Speaker 1: didn't get to see one, but I mean, you know
Speaker 1: they're there, or they're they're sometimes there. These are the
Speaker 1: Oapu Nopili or Stimpson scopie, and these little guys scale
Speaker 1: the vertical cliffs of waterfalls.
Speaker 3: Wow.
Speaker 1: Yeah, you may have seen some videos, some documentary footage
Speaker 1: about these creatures because they're they're amazing and it's an
Speaker 1: amazing journey, especially for something so small.
Speaker 3: You know, I knew about flying fish.
Speaker 1: I don't know why.
Speaker 3: I'm more impressed by climbing fish climbing up trees and
Speaker 3: cliffs than I am with flying fish.
Speaker 1: So coming back to the mud skipper though, Yeah, they
Speaker 1: have specialized morphology for semi aquatic living on these mud flats.
Speaker 1: They can breathe air through their skin and the lining
Speaker 1: of their mouth the only while wet. You often see
Speaker 1: images of them and footage of them with them with
Speaker 1: their mouths opening and so forth. They also do this
Speaker 1: as part of like a defensive display between males It's
Speaker 1: a lot of great footage of that of these males
Speaker 1: combating each other and having standoffs on the mud. They
Speaker 1: are excellent soft sediment burrowers as well, burrowing in the mud.
Speaker 1: This is key to their egg laying. They build these burrows,
Speaker 1: they lay their eggs in the mud. Also, this is
Speaker 1: how they avoid predators. They jump down those burrows get
Speaker 1: out of sight of anything that's trying to eat them.
Speaker 1: And they also use these for thermoregulation as well. They
Speaker 1: also work to maintain an air pocket inside the burrow
Speaker 1: for prolonged stays in low oxygen environments. And you might wonder, too, well,
Speaker 1: how do they bring the mud back up? While they
Speaker 1: bring it up in their mouths. They bring big mouthfuls
Speaker 1: and they spit out these mud balls beside the burrow.
Speaker 1: Joe I included an image of a mud skipper spitting
Speaker 1: mud sort of a ball. It's not as cartoon cartoonally
Speaker 1: ball like as you might imagine, but here's a mud
Speaker 1: skipper spitting mud.
Speaker 3: So this is the equivalent of you're digging a hole
Speaker 3: in the ground with the shovel, you're throwing the mud,
Speaker 3: or not the mud, the dirt over your shoulder. Here
Speaker 3: it is digging in this wet mud, a sort of
Speaker 3: tunnel in the mud, and it is spitting out the uh,
Speaker 3: the the excess that's being voided from the cavity it's
Speaker 3: making exactly.
Speaker 1: Yeah. The other interesting thing about them, like they're their
Speaker 1: morphology positions, their eyes atop their head. They have these
Speaker 1: big eyes that you might not catch what it is.
Speaker 1: It's amazing about them when you're watching them. That makes
Speaker 1: them somehow more relatable and more human like. And part
Speaker 1: of that is is that they blink. Uh, they've and
Speaker 1: they evolved this independently of terrestrial tetrapods.
Speaker 3: Well, I said this about Gobie's earlier in general. But
Speaker 3: the yeah, the mud skippers do seem relatable in a
Speaker 3: way that a lot of fish don't.
Speaker 1: Yeah, and they're just yeah, they're they're crawling around on
Speaker 1: the mud flats. They're engaging in these standoffs with each other.
Speaker 1: And I think the other part is like, unlike a
Speaker 1: fish in the water, of course, in this case, they
Speaker 1: are also interacting, you know, on on a surface. They're
Speaker 1: they're they're out of that three D marine environment and
Speaker 1: here they are on the mud behaving. Is these just
Speaker 1: strange creatures that that you know that almost feel very
Speaker 1: alien compared to anything else because they're they're they're not
Speaker 1: exactly like anything in the water, and they're not like
Speaker 1: anything on the land. They're they're totally doing their own thing,
Speaker 1: and they're doing it in this strange, like muddy, kind
Speaker 1: of slimy environment.
Speaker 3: I mean, I guess they look like a cross between
Speaker 3: fish and frogs, which makes sense because they are amphibious fish.
Speaker 1: Yeah. I want to say, it's BBC's Life, one of
Speaker 1: the David Attenboroughs that has some tremendous footage of these
Speaker 1: guys going about their business, and I think they even
Speaker 1: used to they put a camera down in one of
Speaker 1: their burrows so you can see how that's that's going.
Speaker 1: Some really remarkable footage that's from it's probably at least
Speaker 1: ten years old now, but it's out there.
Speaker 3: See how it's going.
Speaker 1: Yeah, it's it's it's going great down there.
Speaker 3: Now we're the ones saying, hey, guys, what's up?
Speaker 1: Yeah, all right?
Speaker 3: Should we call it there for part two?
Speaker 1: Yeah? I think so. I mean, I think that's a
Speaker 1: good overview of some of the ways that animals use mud,
Speaker 1: Like most of the major categories of mud use and
Speaker 1: some of the more exciting and notable cases. I'm sure
Speaker 1: we left off some interesting ones, So if there's one
Speaker 1: that you really love, just write in let us know.
Speaker 1: We'll highlight it, perhaps in a future episode of Listener Mail,
Speaker 1: Because yeah, it's the realm of mud. Is this world
Speaker 1: that is easy. It's easy for us to take it
Speaker 1: for granted and not realize just how versatile it is
Speaker 1: and how essential it is for various organisms. So we're
Speaker 1: going to have at least one more episode regarding mud
Speaker 1: this Thursday. Tune in for that. This is going to
Speaker 1: be the one where we're going to come back and
Speaker 1: discuss mud and warfare a little bit, but we're also
Speaker 1: going to discuss the importance of mud as a human
Speaker 1: construction material or the creation of mud bricks and so forth.
Speaker 1: In the meantime, if you would like to listen to
Speaker 1: other episodes of Stuff to Blow your Mind, you will
Speaker 1: find them in the Stuff to Blow your Mind podcast feed.
Speaker 1: We have our core episodes on Tuesdays and Thursdays, Listener
Speaker 1: Mail on Monday, Form Artifact or Monster Fact on Wednesday,
Speaker 1: and on Fridays, we set aside most series concerns to
Speaker 1: just talk about a weird film on Weird House Cinema.
Speaker 3: Huge thanks to our excellent audio producer, JJ Posway. If
Speaker 3: you would like to get in touch with us with
Speaker 3: feedback on this episode or any other, to suggest a
Speaker 3: topic for the future, or just to say hello, you
Speaker 3: can email us at contact at stuff to Blow your
Speaker 3: Mind dot com.
Speaker 2: Stuff to Blow Your Mind is production of iHeartRadio. For
Speaker 2: more podcasts from my Heart Radio, visit the iHeartRadio app,
Speaker 2: Apple Podcasts, or wherever you're listening to your favorite shows.