From the Vault: The Glorious Hermit Crab, Part 3
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Hello and welcome to Stuff to Blow Your Mind. I am Joe McCormick. Normally on Tuesdays, we would have a new core episode of the show for you, but our team has some stuff going on early this week. So today we are bringing you an episode from The Vault. This is part three of our series on The Hermit Crab, and it originally aired on January 11th, 2024. Uh,

After today's vault, we're going to be back with all new stuff for you the rest of this week. So I guess that's everything. Let us seize the empty shell. Welcome to Stuff to Blow Your Mind, a production of iHeartRadio.

Hey, welcome to Stuff to Blow Your Mind. My name is Robert Lamb. And I am Joe McCormick, and we are back with part three in our series on hermit crabs. Now, if you haven't heard the first couple of parts of the series, you might want to go back and listen to those first.

But also, if you just want to start here, that's fine. I don't know if there's any particular order you need to do these in. In the previous two episodes, we talked about Rob's recent in-person observation of terrestrial Caribbean hermit crabs in the wild, which sounds fascinating, watching them scuttle about and do their business. We talked about the way hermit crabs fit into the crustacean family tree, how they differ from so-called true crabs or the brachyura family.

how they evolved to depend on exogenous mobile shelter in the form of things like gastropod shells. We talked about how hermit crabs forage and compete for shells within a kind of economy, and how this leads to an interesting phenomenon called vacancy chains, with parallels in the markets for some certain human resources, such as housing and certain kinds of jobs.

We discussed some surprising evolutionary relationships, such as the widely supported idea that free-living king crabs, yes, even the kind you eat, probably evolved from a hermit crab ancestor. So the lineage, if this hypothesis is right, the lineage evolved once from free-living crabs to

to the hermit crab form, where it developed a soft, wormy abdomen and evolved to depend entirely on these externally sourced shells. And then some branches of that family evolved once again to abandon the external shells and become fully hardened all over, become these free-living crab-like organisms again. King crabs are also anemura. They're also not so-called true crabs.

And also we discussed some fascinating alternatives to the common relationship between hermit crabs and snail shells. The majority of hermit crabs do prefer to live within the shells of gastropods, snails, whelks, periwinkles, those kind of things. But there are also hermits that take up residence within living sea anemones or solitary corals. And so we talked about the reasons those relationships could be mutually beneficial.

That's right. And as we discussed, too, I mean, there's still so much research going on concerning hermit crabs and the discovery of new, particularly aquatic hermit crab species and just fully understanding terrestrial hermit crabs as well.

So, you know, we're not going to be able to touch on everything in this trilogy, but we are going to finish the trilogy here. We're going to finish our story of Hermit Crabs, and we're going to get into a few remaining and perhaps surprising areas of discussion. So the first thing I wanted to talk about today is

was that I was quite interested to find some meditations on hermit crabs in the writings of the late Stephen Jay Gould, the American paleontologist and popular science communicator. So first of all, I did find that Gould wrote a good bit on the hermits to kings hypothesis that we talked about in the previous episode, where king crabs are thought to have probably evolved from hermit crab ancestors. Yeah.

Did he have a particular take or was he just generally reporting on the back and forth among evolutionary scientists? Well, I saw that he wrote on this subject. I did not read everything he did write on this subject, so I don't know where he landed in the end. I'm just going to assume he probably landed where everyone else seems to be and that is, well, most people agree that this hypothesis is probably correct. It seems to be the scientific consensus.

That seems likely to me. But beyond that, I found a really interesting anecdote about hermit crabs in an essay called Nature's Odd Couples from Gould's 1980 collection, The Panda's Thumb. This essay was great because the core observations from Gould are fascinating, but it also sent me off on a pretty good tangent that I hope you'll enjoy about snails with what look like bloody teeth. Yeah.

So Gould opens this essay with a quote. He opens by talking about a quote from Alexander Pope's poem, An Essay on Man. And it's a, it's a rhyming couplet. It goes like this from nature's chain, whatever link you strike 10th or 10,000th breaks the chain alike. And he kind of starts by appreciating some ways in which this quote is both is and is not true. So Gould,

In the sense in which the spirit of the quote is true, organisms throughout an ecosystem are all connected by various types of relationships. There are energy relationships. You know, some organisms eat one another or affect how one another can acquire energy. There are information relationships. Sometimes organisms learn about something from another one and so forth. And these relationships can be both direct and indirect relationships.

So things that happen to one organism can ripple through the whole ecosystem in surprising ways. On the other hand, it's

it's obviously not the case that the chain of nature, to use Pope's image here, is completely destroyed any time one link is broken. Gould writes, quote,

It could not be, for extinction is the common fate of all species, and they cannot all take their ecosystems with them. Species often have as much dependence on each other as Longfellow's ships that pass in the night.

And to add to this, I would just say it's a very safe estimate that more than 99% of species that have ever existed are already extinct. The American Museum of Natural History uses the estimate that it's more than 99.9% of all species that ever existed.

So obviously, it's just not the case that a single link is broken and the entire chain is necessarily shattered or life couldn't exist today. Ecosystems, in many cases, survive and adapt. They adapt to changes in their makeup.

But to come back on the other hand, it's absolutely true that the extinction of one organism in an ecosystem can be absolutely devastating and it can lead to secondary extinctions. And from a human perspective, a major danger here is the lack of predictability in these kinds of relationships. Like sometimes we can predict what these relationships and domino effects would be, but sometimes we can't.

We don't always know what would happen to a whole environment and ecosystem when one species is taken out of the equation. That's right. And we've talked about that before in terms of situations where there is very much an organism we would like to remove from the ecosystem or from parts of the ecosystem, such as, say, a mosquito.

or some other pest, something that is interfering with human aims and industries. But the question always remains, like, well, what else is that organism doing? What eats it? What is kept in check by it? And so forth. And so there are all these spiraling concerns. And, you know, it's kind of like that...

It reminds me of that old saying, I think from some movie or another about how if you're going to rob a bank or something, you know, there are like so many ways you can mess up. And if you can think of like three of them, you're a genius. It's it seems like a similar situation. Anytime humans want to mess with the ecosystem, with the introduction or removal of certain species, there are the things that you know can occur or likely will occur if you change it. But then there are all these additional ripple effects that you cannot necessarily predict.

Right. So it's not the case that breaking one link in the chain necessarily shatters the whole chain, but it does change the chain and you might not like the way it changes. Yeah. Yeah.

So we don't always know what's going to happen when one species is taken out of the equation. And in fact, we can assume the organisms in question don't know either. And what's more than that, the algorithm of evolution itself, in the metaphorical sense that it can know anything, cannot be said to know in advance what will result from extinctions, which is why so many organisms evolve so

dangerous, precarious relationships. In many cases, organisms evolve unbreakable dependencies on another specific organism. For example, a predator that is specialized to eat only one type of prey. If that prey organism disappears, the predator is doomed. Or,

or a plant that relies on a specific animal to help it pollinate and reproduce. One common example cited here are yucca plants and yucca moths, which both rely on one another in a system known as obligate mutualism. Yucca plants have to be pollinated by yucca moths, and yucca moth larvae grow in the yucca plants and grow by eating some but not all of the yucca seeds.

And though with the yucca plant, the yucca moth, the relationship goes both ways. Some of these relationships don't go both ways. Sometimes they're only one way. Again, think of the predator that can only eat one species for food.

So while these highly dependent relationships can be helpful specializations at a specific time in a specific environment, they're good for helping you survive. Now, they're sort of analogous to like putting all of your life savings in a single stock, you know, like if the company's doing well, that's great for you. But if it goes bankrupt, you lose everything. Right.

And sometimes evolution selects for creatures that do not have diverse survival strategies. They're all in on a single ecological partner. And this brings us back to Gould's essay where he talks about a couple of examples where we see what happens to a pair of species that either depend on each other or one depends on the other in this way. The odd couples of the essay's title, what happens to them after a sudden disruption?

And one of the examples he talks about is a hermit crab. So Gould recounts some of his days as a graduate student when he was writing his Ph.D. dissertation on the land snails of Bermuda. So he was in Bermuda and he says while he was exploring the shores and the beaches there,

He would quite often come across hermit crabs, but not just any hermit crabs, large hermit crabs crammed into a shell that was way too small for them. He would talk about like their big claw protruding out of the shell. And he says that these tiny shells that they were trying to fit into were shells of the narrated snail.

Which he points out includes the what he calls, quote, the familiar bleeding tooth. That was not familiar to me. I had no idea what he's talking about with the bleeding tooth there. I had to look that up. And so I'll come back to that in a minute.

I can't wait. But on the general subject of the Neretid snails, this is a fairly lengthy digression, but I had to look up this animal because they came up a couple of times. We talked about Neretids in the first episode of this series, and I didn't really know anything about them. So I looked them up and I found some interesting backstory. Neretids or Nerites are named after a minor sea god from Greek mythology who was called Neretes.

And it seems that the main written source on the Neretes myths is the second to third century Roman author Elian in his book On the Nature of Animals.

I think this specific text came up in a series we did not too long ago on beavers, because Eilean is the source of the ancient story about how male beavers would bite off their own testicles and offer them up to hunters to make the hunters stop chasing them. I believe we judged this story not true, but Eilean has a lot of interesting animal facts of that kind. But he also has some backstory on the narrated sea snails.

So I'm going to alternately quote from and summarize Elion's text here. This is from the A.F. Schofield translation of Elion's On the Nature of Animals. He writes, quote,

Then this was funny. He goes on to make some excuses for why it is OK that he's about to tell a couple of stories in the middle of this very serious book. He says it is going to sweeten the work. So, OK. Yeah, like a little bit of a little bit of lead sprinkled into your wine, right? Exactly. Yeah. The lead sugar.

So anyway, there are two stories about how this animal came to exist. And in both cases, the stories trace back to an extremely handsome hyperhunk deity named Nerides, who is the son of the sea god Nereus and of the sea goddess Doris, the daughter of Okeanos.

So in the first story, we learn that Nerides was so overwhelmingly handsome that he became the favorite of the goddess Aphrodite and she fell in love with him. And Elian writes, quote, And when the fated time arrived at which at the bidding of the father of the gods, Aphrodite also had to be enrolled among the Olympians. I have heard that she ascended and wished to bring her companion and playfellow. That'd be Nerides.

But the story goes that he refused, preferring life with his sisters and parents to Olympus. And then he was permitted to grow wings. This, I imagine, was a gift from Aphrodite. But even this favor he counted as nothing. And so the daughter of Zeus was moved to anger and transformed his shape into this shell.

and of her own accord chose in his place for her attendant and servant Eros, who was also young and beautiful, and to him she gave the wings of Nerides.

Very spiteful, very much like her father. That's true. So, Nerides liked his home in the sea. He was not ready to move in with Aphrodite's family on the mountain. So, you know, even though she gave him wings and everything, he didn't want to budge. So she transformed him into a sea snail out of revenge. And it's interesting, it says...

Specifically that he was transformed into the shell. I assume that means the whole animal, including the snail. It would be funny if it just transformed him into the shell and a snail had to live in him. But that would very much fit with a lot of what we've been talking about with hermits.

I guess that's true. And so this story, it kind of matches the general form of these Greco-Roman metamorphosis stories. You know, somebody offends a god in some way and they're transformed into something else. But I was wondering, like, why a snail in particular? I'm not sure if I'm missing something about this story, but I feel like Elion's next story has a little bit more of a hint about that element, like why he would be transformed into a snail. Yeah.

So the next story starts the same. Nerides was a young, extremely handsome sea god. But this time, instead of becoming the favorite of Aphrodite, he becomes the favorite of Poseidon and he becomes Poseidon's charioteer. Hmm.

So, Elian writes, quote,

Only the boy favorite was his escort close at hand, and before them the waves sank to rest and the sea parted out of reverence to Poseidon, for the god willed that his beautiful favorite should not only be highly esteemed for other reasons, but should also be preeminent at swimming.

But the story goes from here that Helios, the sun god, was jealous of the speed of Nerides and transformed him into the snail with the spiral shell. And Elion says, commenting on the story here, that he doesn't know why Helios was angry at Nerides, but guesses that either Poseidon and Helios are enemies or

Or perhaps that Helios was jealous that the handsome guy was down in the sea with Poseidon instead of flying among the stars with him. Yeah, I mean, really, it's standard God drama right here. But exactly. But in this version, at least, Nerides is known for being fast, right? So he's fast and then he's transformed into a snail. Something seems more fittingly ironic about that punishment. Yeah.

Oh, yes, yes, you're right.

Their diet most of the time consists of algae that they eat off of rock surfaces in the water as they crawl around on a rock, sort of scraping up algae and eating it. And they tend to be pretty small or sort of considered small to medium snails. So it is quite pitiable to imagine, as Gould describes, a population of hermit crabs where even fairly large individuals are trying desperately to cram into these tiny shells. ♪

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like in-depth interviews and a roundup of the week's top headlines. Listen on the iHeartRadio app, Apple Podcasts, or wherever you get your podcasts.

I'm Jason Alexander. And I'm Peter Tilden. And together on the Really No Really podcast, our mission is to get the true answers to life's baffling questions like why they refuse to make the bathroom door go all the way to the floor. We got the answer. Will space junk block your cell signal? The astronaut who almost drowned during a spacewalk gives us the answer. We talk with the scientist who figured out if your dog truly loves you and the one bringing back the woolly mammoth. Plus, is

Does Tom Cruise really do his own stunts? His stuntman reveals the answer. And you never know who's going to drop by. Mr. Bryan Cranston is with us tonight. How are you, too? Hello, my friend. Wayne Knight about Jurassic Park. Wayne Knight, welcome to Really, No Really, sir. Bless you all. Hello, Newman. And you never know when Howie Mandel might just stop by to talk about judging. Really? That's...

It's the opening? Really, no really. Yeah, really. No really. Go to reallynoreally.com. And register to win $500, a guest spot on our podcast, or a limited edition signed Jason bobblehead. It's called Really, No Really, and you can find it on the iHeartRadio app, on Apple Podcasts, or wherever you get your podcasts. Now, the one thing I said I was going to come back to was that Neurite Dick Gould mentions by name in his essay, the so-called bleeding tooth.

He doesn't say anything else about it, so I got curious about this as well. And I found a good photo with some interpretive text on the website for the Bailey Matthews National Shell Museum in Florida, USA. Rob, I attached the pictures for you to look at here. And first of all, I got to give credit to whoever named this because they're right on the money. It does look like a pair of bloody teeth. Absolutely disgusting. This is easily the most disgusting shell I've ever seen. Usually I'm a big shell fan.

No matter what kind of creature lives inside it, like show me the shell. And yeah, it's just generally pretty stunning. Or even a very plain shell is pleasant to behold. This is gross. This looks like misshapen teeth emerging from inflamed and recessed gums.

It's what like the dentist would scare the children with on The Simpsons. Yeah. Yeah. You'll see brochures with images like this at your local dentist office. Makes me kind of want to make a fake brochure with images of this shell and just sort of slip them in among the other brochures next time I go in. It makes me want to leave this session and go like brush and floss right now. Yeah. We can take five. See you later. I'm in favor of dental health.

Anyway, so yeah, you can look these up, the bleeding tooth neurite. Anyway, this is on the inside of the shell orifice. So you can imagine it's kind of a spiral and it's got the opening. So if you're looking at the opening, the side of the aperture that is closest to the central column or axis of the shell, that's where the bloody looking teeth are.

And the museum page says that this is the species Nerida pelleronta, and it's a snail commonly found on shores throughout the Caribbean and Florida. It reaches a maximum of about two inches or about 50 millimeters in size. And in an interesting parallel to the shell remodeling we saw in some land-dwelling hermit crabs,

The bleeding tooth snail will sometimes dissolve the interior surfaces of its own shell to give itself more space inside and also to make room for a kind of water tank reserve, to make room to retain reserves of water inside the shell, which is apparently useful for the snail during low tide.

Yeah, yeah. This is essential to what we were talking about in the first episode here on hermit crabs, about the chemical and physical augmentation of the shells that hermit crabs use. And so most of the shells that hermit crabs are competing for have been augmented, have been remodeled. Yeah, and it's interesting that I think we've uncovered at least two different ways now.

sort of initially hidden ways that you might not know about just by looking at them, that some hermit crabs have evolved the same adaptations to shell life as the snails that originally made the shells they inhabit.

So the first example we talked about was hermit crabs evolving asymmetrically sized claws so they can use one claw as an operculum, which means an aperture covering, you know, a door to close a hole. And they use that larger claw to close the hole of the shell when they retreat inside. And the parallel with the snails is that many snails have the same adaptation. It's part of their bodies. They often have a hard plate called an operculum.

that closes over the shell aperture when the snail goes inside to hide. So like the hermit crabs evolutionarily recreated that function with their claws. And now we see examples of both snails and later hermit crabs that inhabit the same types of snail shells, taking a calcified shell of a fixed size and then dissolving some of the interior surfaces of that shell to make more room or make it better suit their needs.

Yeah, it's amazing. But anyway, so after this whole narrative digression, coming back to Gould and his essay, so he says that he saw all these hermit crabs in Bermuda trying to survive by cramming their big old bodies into the shells of narrated snails, which were way too small for them.

But then he says one day he came across one of these larger hermit crabs with a better fitting shell, a much bigger shell. And this was not from a narrated snail, but in this case from a whelk. It was a species called Cetarium pica, commonly known as the West Indian top shell.

And this is a larger variety of sea snail, which is eaten as food in many places throughout the Caribbean. But when Gould went in for a better look, he realized that the cetarium shell occupied by this hermit crab was no ordinary gastropod shell. It was a fossil.

Oh, my goodness. Yeah, a living crab inside a fossil shell. So Gould writes that it seemed the fossil had probably been dislodged by the tide from an ancient sand dune where the original shell was deposited roughly 120,000 years ago, probably deposited there by an ancestral hermit crab.

So hermit crab takes the shell out of the water up to this area. It gets buried in the sand. It gets fossilized. And then 120,000 years later, the fossil comes out and a hermit crab claims it. That is amazing. I mean, you would hope that he would get those specially antique car tags for that shell, right? Yeah.

So Gould continued to study the hermit crabs in the following months, and he saw that most of them were confined to these cramped narrated shells, but the few lucky animals to possess a whelk shell always turned out to be living in a fossil.

So Gould did some library research and he discovered that he wasn't the first person actually to make this observation. He had been beaten to it by the Yale taxonomist Addison E. Verrill in the year 1907. So what on earth was going on here?

Well, Gould found that Verrill had had researched the same issue and Verrill had gone back through the history of Bermuda to try to find references to these whelks to see if anybody recorded ever seeing them alive or.

And it turns out that some of the earliest written records of the island actually do mention the whelks. So here to read from Gould, quote, Captain John Smith, for example, recorded the fate of one crew member during the Great Famine of 1614 to 1615. Quote, one amongst the rest hid himself in the woods and lived only on whelks and land crabs, fat and lusty, many months. Yeah.

Is that fat and lusty? Is that describing the the the whelks and the land crabs or just the land crabs or the guy who is eating them? I think this is the guy eating them. I just imagine him just laying about fat and lusty, just stuffed with these creatures.

Snail and crab for many months. That's got to wreck you. That's got to wreck you. That's so bad. Gould goes on to say, quote, another crew member stated that they made cement for the seams of their vessels by mixing lime from burned whelk shells with turtle oil.

Okay, so some of the earliest references to these animals are people eating them and grinding them up and burning the shells to make cement.

And then also the last evidence that Verrill could find of living cetarium whelks in Bermuda was, quote, from kitchen middens of British soldiers stationed on Bermuda during the War of 1812. So, yum. Military rations, including a lot of sea snail here. All right. We can definitely see where all this is going.

Yeah, because apparently no record of them turned up in the many years since then. It appears that while these sea snails, the whelks, still exist elsewhere, they were locally extinct in Bermuda. So Gould observes another one of these scenarios, kind of like the post-apocalyptic movie we talked about in the first episode, where in that case it was the land hermit crabs fighting over a scarce pool of these orca

Yes, yes, that's my understanding.

So, yeah, in this case, they would be in a position to where the desired shells are no longer around or around in such short supply due to human interference that they have but one option. Right. Right. So the shells they really want, or at least once they get larger, the shells they really want are an extremely scarce resource. There are maybe some shells still kicking around within the hermit crab economy, though gold remains.

says, you know, he never came across those. But he says that they're still recycling shells of the previous centuries from before these animals were wiped out. And these shells, you know, they're strong, but they don't last forever. They get battered around by the waves. They get knocked on rocks. They get damaged over time. Stuff happens to them. So that supply is going down. And the only options they have other than that, which apparently those are already very rare, are

These these, quote, new shells, which are actually fossil shells coming down from the fossil dunes like they come out of the earth sometimes or these tiny narrated shells, which are too small for them. So, yeah, it's a kind of it's a kind of sad situation there.

And he actually does make exactly the comparison that we made in the previous episode to kind of like a post-apocalyptic Mad Max scenario where it's just this dwindling supply of original resources being fought over. And it probably means that the hermit crabs in this specific location do not have a bright future ahead. This essay is from, I don't know,

probably the late 70s or around 1980. I don't know exactly what their status is now. Yeah, because...

I imagine the fossilized shells were heavier. At any rate, they would not be ideal, but they are close enough and they're all that the crabs can upgrade to in this case. So that's fascinating. It's also, one can't help but sort of put a fantastic spin on it and imagine the hermit crabs gathering and they're like, the humans have destroyed our prized shells. We have no choice but to retrieve the fossil shells. Right.

that of course may resonate with arcane powers. Well, that's fascinating. I had no idea that we had hermit crabs trooping about in fossilized shells. That's amazing. Oh, and by the way, if you get a chance to read the Gould essay, the thing about hermit crabs is only the first half of it. The second half is actually an interesting sort of meta story about science because the second half is about another relationship, one that is alleged to

to have existed between the dodo and a plant that had an obligate relationship with the dodo and how that allegedly would have affected the plant when the dodo was driven to extinction by human activity. But that story actually has a postscript in the essay because then later research came along to challenge the suggestion that it was the extinction of the dodo that affected the plant.

So overall, it's an interesting essay. You want to, I guess, find the version with the postscript that hashes out all of the debate and controversy about that second story. ♪

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All right. For the last phase of this episode, I want to dive a little bit more into mythology concerning hermit crabs. So we've discussed crabs in the show before, obviously, and we've touched on the at times surprising lack of supernatural and divine crabs in global traditions. We touched on a few examples, the more notable examples in our 2021 episode on crabs eating weird stuff. I can't remember if

what title we went with on that. That may, it might be the actual title, but we talked about the various things that crabs eat and the curious ways that they eat them, eat the stuff. You know, they, they basically like, uh, take it apart. It's like reverse 3d printing, uh, with their, their tiny, um, uh, feelers and mouth parts. Um,

But in that, for instance, we also mentioned another example that's not really an example of a mythology about a lobster, but the invocation of mythology and the naming of, in this case, the squat lobster, Kiwa hirsuta. This is actually a species that I mentioned briefly in one of the previous episodes, and it's named after a Maori sea god.

So again, not a direct connection to mythology, but like an invocation of mythology. But I was wondering once more about all this. I was like, okay, are there any myths or folktales involving the hermit crab? And once more, not a lot of examples came up. And you can probably tease that apart different ways. Is it that hermit crabs are just ubiquitous in certain areas and therefore mythological?

not deserving of such treatment or in other areas, they're just not known and therefore they're not invoked. Um, or, you know, there's plenty of room too, for things to just become lost. Not everything that, uh, that, uh, that indigenous peoples and, um, and ancient peoples thought and believe have been passed down to us. But I did find some interesting thoughts about how hermit crabs maybe just maybe fit into the Mayan pantheon. Oh,

Oh, interesting. So of note is a particular guide depicted in the Mayan codices, those folding books written by the pre-Columbian Maya civilization in Mayan hieroglyphic script that survived colonial destruction.

And this particular god is often cataloged as God-in. That is not what worshipers have said God would have called this god, but historians and researchers would classify them as such. So God-in, but also known under the names Bacab, as well as sometimes the name Poyutun.

Now, according to the article Maya Creator Gods by K. Bassi, God N and the Mayan creator God Itzamna, which is also known as God D in this classification system, these may be different incarnations of the same God.

Furthermore, it seems that there were four different incarnations of God in, one for each cardinal direction, and these are often referred to as not just Bacab, but the Bacabs, but also they are all the Bacab. Essentially, this is like a fourfold God.

And so this particular god is associated with four directions, four colors, four cosmic pillars, but also with the Earth's interior and with its water reserves. Now, as Bassey points out, there are various visual depictions of Bacab, often as a kind of like human with almond shaped eyes,

sometimes with a water lily headdress, other times a net bag headdress. But other times this god is depicted as wearing or inhabiting a turtle shell. Sometimes they take on avian features. They are also sometimes presented as an old man or perhaps an old possum. They also are sometimes depicted as, quote, wearing a spiral shell or emerging from it. Hmm.

Now, Joe, I did not include images of this for you here in our outline because these are very hieroglyphic in nature and they don't necessarily read easily to the untrained eye. But the Bessie does include various examples of what they're talking about here. Now, in this paper, the researchers have not mentioned crabs or hermit crabs at all.

But I did run across some musings by Dr. Nicholas Helmuth on a website that is maya-ethnozoology.org. This website is a project of the Biodiversity Educational Organization, FLAAR, Mesoamerica. He's an expert in Mayan iconography based out of Guatemala. Hmm.

He discusses that there are various representations of god in /pahutun /pahutun/baqab. There's the turtle shell emergent variant, and then there's this version where the god is within a shell. Sometimes it's described as a spiral snail shell. Other times it's described as a conch shell. A conch, we'll remind you, is a variety of sea snail known for its shell as well as sometimes for its meat.

It's often used in a lot of, you'll find it in like chowders or stews, sometimes fried up as well. So the author here points out that while the shell is often glossed over by researchers, you know, people will say, oh, it's a shell, maybe a snail, maybe a conch. I mean, we don't know.

But he points out that, OK, it would be nice to know. It would behoove our understanding of Mayan culture to specify snail shell or conch shell, both of which would have been known to the Mayans. He also stresses that certainly the Mayans and the Aztecs alike were capable, you know, very much of creating imagined combinations of beings. So it's not one of those situations where there has to be this one thing that directly feeds into the idea.

And then, of course, there are many other sorts of shells to consider. But, you know, it's basically it's an interesting question coming from an individual here who has

I believe, you know, on one hand, very interested in Mayan iconography, but also devoted to various projects that involve classifying and chronicling the biodiversity of the region. Anyway, he stresses that a great deal of additional research needs to be done in this area, but he ponders whether the model for Gaudian might have been a hermit crab, if not for the god entirely, at least for one phase of the deity, one of the four aspects of Bacchus.

Ah, that's interesting. So, yeah. So, like, because if you see a spiral shell, one, you might be tempted to assume it is supposed to be associated with the animal that creates the shell originally, but the shell is equally associated with the animals that inhabit it after the original animals are dead. Yeah.

Yeah. Yeah. So this this got me really excited. But then sadly, he doesn't have much to say about the idea because basically it was like, well, you know, maybe this is something we can look into later.

But it was just enough to sort of, you know, to inspire me a little bit and think, well, yeah, what are the possibilities there? And does it mean like that the god occupies different housings like the turtle shell and then the snail or conch shell? I don't think that's necessarily the case or more likely that like just one phase of the entity is perhaps based on a hermit crab.

And he also points out that like, he's like, I can't be the only person who has thought of this idea. And yet I can't really find any other references to it. And I looked around, I couldn't really either, but I did find mention of the hermit crabs mythological significance in

in a paper titled Late Post-Classical Ritual at Santa Rita Corozal, Belize, Understanding the Archaeology of a Maya Capital City. This is by Diane Z. Chase and Arlen F. Chase. This is published in Research Reports in Belizean Archaeology.

So Chase and Chase point out that they're basically, this paper deals with an analysis of depictions of various animals in Mayan iconography. They point out that there are several animals that seem to represent the

the underworld and the surface of sort of the surface level of our reality, like the borderland between the, I guess you could call it the natural world or the visual world and the world of the unseen. And furthermore, that these animals could take on supernatural significance as entities that can travel between those worlds or travel at the very barrier of those worlds.

They specify the turtle. And of course, we already talked about the turtle's significance in my iconography depicting this particular deity. But also the caiman, the shark, specifically the shark's fin as it breaks the surface of the water. Like here is an organism that is literally in both worlds at the same time. And they reference the hermit crab. Hmm.

So they point out that, OK, the hermit crab does not really live at that boundary point. It's not like the fin of the shark where it's poking through or anything. It's not like the turtle coming up for air. But they do stress that hermit crabs across many species, of course, are found both on the shore and underwater.

Plus, as we've discussed, we know that terrestrial hermit crabs are still intrinsically bound to the ocean as well. I mean, the reproduction depends upon it. So they are not 100 percent terrestrial. They are still creatures of the ocean that live upon the land. So they reference the creatures as well in comparison to various ceremonial urns.

The lids of which are not merely lids, but represent the surface of the visible world or this barrier between our visible world and the world of the unseen, which in this case would be like the interior of the urn, the interior of this vessel.

You know, just as the surface of the water, both from the standpoint of, you know, surface versus aquatic life, as well as just symbolic thinking, is this barrier point. Ah, that is interesting. And yeah, the hermit crab not only is an animal that could inhabit a kind of boundary environment, but also crosses from inside to outside in that way, you know, crosses from the inside of its shell to the outside to crawl around. Yeah. Yeah.

So I'm left trying to imagine the hermit crab as kind of a psychopomp kind of an entity, like a creature that is here to guide you through to the underworld. I mean, I don't think that's what the authors were directly getting at here. But still, this idea of the hermit crab is this kind of

creature with an innate understanding of the threshold between our world and the next, you know, as this creature that travels both sides. And like I think I referenced in the first episode, you know, I saw the terrestrial

hermit crabs in Belize. And then when I went in snorkeling, I also saw at least one aquatic hermit crab underwater. And so there is kind of a sense of like, hey, you're under here too. You guys are all over the place. You get around. You know what it is to travel between worlds. And apparently across time as well, sometimes living in a house forged 100,000 years ago. Yeah.

No, it is interesting to think of all this, like compared to those other animals I just referenced, like, you know, the sea turtle, for instance, is very majestic to behold in the water. And you can imagine this is a interdimensional traveler. Likewise, the caiman and the shark may take on even sinister qualities like, yeah, of course, these are creatures.

that have ventured into the underworld. But the hermit crabs, you know, they just seem very busy. They seem too busy to really waste much time in instructing you about the barrier between worlds.

Well, Rob, I have greatly enjoyed this exploration of hermit crabs, and I feel like we may have to come back to them because I know there's a lot of stuff we didn't even get to. Yeah, yeah. Again, this is a thriving area of scientific research. New discoveries are taking place. New papers are coming out all the time. So, yeah, we might we might return to the world of hermit crabs in the future. We'll definitely return to the world of crabs. You know, it ain't the holidays unless we're talking about crabs.

All right. We're going to go ahead and close it out here. We'd love to hear from everyone out there. If you have observations concerning hermit crabs, if you have insight on any of the topics we've discussed in these episodes, write in. We would love to hear from you. Just a reminder, The Stuff to Blow Your Mind is primarily a science podcast with core episodes on Tuesdays and Thursdays.

We do Listener Mail on Mondays. We do a short-form episode on Wednesdays. And on Fridays, we set aside most serious concerns to just talk about a weird movie on Weird House Cinema. Sometimes there are giant crabs involved.

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