Speaker 1: Hey, welcome to Stuff to Blow your Mind. This is
Speaker 1: Robert Lamb. Today is Saturday, of course, so I have
Speaker 1: a vault episode for you. And oh, this one published
Speaker 1: a year ago this very day. This published on one
Speaker 1: four twenty four. It is part one in our series
Speaker 1: on the Hermit Crab. I hope you enjoy.
Speaker 2: Welcome to Stuff to Blow Your Mind, a production of iHeartRadio.
Speaker 1: Hey, welcome to Stuff to Blow your Mind. My name
Speaker 1: is Robert.
Speaker 3: Lamb and my name is Joe McCormick. And we're back
Speaker 3: after the holidays. All right, I guess you've already been back, Rob,
Speaker 3: I'm back for the first time.
Speaker 1: Now, Yeah, that's right. I left a little early and
Speaker 1: then and then I came back to you know, scrambled
Speaker 1: together a few episodes. But now it's time to return
Speaker 1: proper with a true core episode of Stuff Below Your Mind.
Speaker 1: But we're ringing in the new year once more with crabs,
Speaker 1: because of course, crab content is suitable for any holiday,
Speaker 1: and there is an abundance of it, you know.
Speaker 3: I don't know if it's just the name of Christmas
Speaker 3: Island that created this correlation, but I think we tend
Speaker 3: to do crab content in the winter have you noticed
Speaker 3: that that's not on purpose, at least not on my part.
Speaker 1: No, this is great. I think the Christmas Island crab
Speaker 1: thing kicked it off a bit a while back. That's
Speaker 1: part of it. For sure. There's something maybe holiday centric
Speaker 1: about crabs. It also helps that sometimes my family and
Speaker 1: I travel during the winter break and go somewhere where
Speaker 1: crabs are abundant. And yeah, I'm excited to talk about
Speaker 1: crabs once more because over the holidays, my family and
Speaker 1: I were fortunate enough to once more visit Glover's Reef,
Speaker 1: a partially submerged atoll located off the southern coast of Belize.
Speaker 1: Tremendous fun. We stayed on a small island all week.
Speaker 1: There were other human certainly, but we spend as much
Speaker 1: time as possible getting into the water to snorkel to
Speaker 1: check out the fish and the coral. But the predominant
Speaker 1: land organism was, without a doubt, the terrestrial hermit crab.
Speaker 3: So this is a holiday with crabs underfoot.
Speaker 1: Yes, I mean, I don't think anyone ever stepped on one,
Speaker 1: but they were everywhere. Most hermit crab species are aquatic,
Speaker 1: as we'll probably touch on several times during this episode.
Speaker 1: But I'm going to be talking mostly about the terrestrial variants,
Speaker 1: like those that I encountered on this island, that still
Speaker 1: depend on the ocean for reproduction, but which live most
Speaker 1: of their lives on land, and that comes with various
Speaker 1: complications and innovations. And also they're very visible. You know,
Speaker 1: you don't need a snorkel, you don't need a dive
Speaker 1: suit to engage with the world of the hermit crab
Speaker 1: because on places like this they are everywhere and they
Speaker 1: are widespread. You don't also don't have to go to
Speaker 1: Belize to encounter hermit crabs, terrestrial hermit crabs, even they
Speaker 1: are out there.
Speaker 3: So roughly, how big were or how big was the
Speaker 3: range of the ones you were seeing? Is are we
Speaker 3: talking like silver dollar size or hand size? Like what
Speaker 3: are we dealing with here?
Speaker 1: Yeah? The size differential is one of the things that
Speaker 1: makes hermit crab watching in the wild so fun because
Speaker 1: you never know exactly what size you're gonna encounter. Like
Speaker 1: some of the very small ones, you know, oh so cute,
Speaker 1: it's the size of a dime or something, you know,
Speaker 1: it's very small. But other times it'll be like I'm
Speaker 1: probably exaggerating to save the size of a catcher's met
Speaker 1: but at least the size of a very large fist,
Speaker 1: you know, just a just a big chonker of a
Speaker 1: hermit crab. And as you're going, as we were going
Speaker 1: about on the little pathways on the island, you know,
Speaker 1: they would be moving around pretty much all the time.
Speaker 1: That they're very busy. They're constantly trooping about, they're scavenging,
Speaker 1: they're competing for shells. Though I don't think we ever
Speaker 1: directly observed this, but clearly it is happening. And if
Speaker 1: you come across one while it's say, crossing the sand path,
Speaker 1: they'll suddenly stop, and then if you get a little
Speaker 1: bit closer, they'll retreat into their shells, and as they
Speaker 1: do that, that'll cause them to roll over onto their back,
Speaker 1: and then of course they cap the shell opening with
Speaker 1: their larger claw and then give them enough time and
Speaker 1: then get back up and they continue on with their business.
Speaker 3: Mm hmm.
Speaker 1: So yeah, there's just something magical about her crabs, at
Speaker 1: least to someone like me who doesn't get to observe
Speaker 1: them all the time. But even the team on the
Speaker 1: island here, they seem to find a certain amount of
Speaker 1: joy in the creatures, despite how accustomed they were to
Speaker 1: their presence. I heard that one of the cooks brought
Speaker 1: some shells for the crabs with her from the mainland,
Speaker 1: with the names of each of her children written on them,
Speaker 1: and then and then would enjoy like running into various
Speaker 1: crabs who would claim these shells and make them their homes.
Speaker 3: Oh, that's funny. So like when people write funny things
Speaker 3: on a dollar, you know, it's like, are you expecting
Speaker 3: to encounter this again?
Speaker 1: Yeah? Yeah, And yeah. There's just something they're like a
Speaker 1: little like io machines, you know. There's just something about
Speaker 1: how industrious and relentless they are as they scavenge the terrain.
Speaker 1: For instance, at this place that we were staying, this
Speaker 1: a place called Off the Wall. The communal dining area
Speaker 1: at the place has a sand floor, and Jim and Kindre,
Speaker 1: who run the place, told us that first thing in
Speaker 1: the morning, when you go in there, the sand is
Speaker 1: completely devoid of human footprints because during the night the
Speaker 1: crabs have come, the hermit crabs have come, and so
Speaker 1: in the morning they are only crab tracks, and not
Speaker 1: even the slightest crumb left behind, because they have come
Speaker 1: and claimed everything.
Speaker 3: Crab wipe.
Speaker 1: Yeah, so I love it. After experiencing all that, I
Speaker 1: was like, well, we've got to find some more things
Speaker 1: to talk about with hermit crabs. We've talked about them before,
Speaker 1: but now we're going to go in a little more depth.
Speaker 3: Well, it turns out I think hermit crabs are very
Speaker 3: interesting and there is a lot we can talk about.
Speaker 3: So I guess we will start with the basics. What
Speaker 3: are hermit crabs? Are hermit crabs crab? The answer is
Speaker 3: sort of. Hermit crabs are decapod crustaceans that means decapod.
Speaker 3: They're ten legged invertebrates with a hard exoskeleton that grow
Speaker 3: by molting, so they shed their old exoskeleton and emerge soft,
Speaker 3: and then a new exoskeleton hardens when they need to
Speaker 3: get bigger when they grow bigger. But they are considered
Speaker 3: distinct from what are called true crabs. True crabs belong
Speaker 3: to the infraorder Brachyuria. Hermit crabs belong to the related
Speaker 3: infraorder animura a n O m U r A. They're
Speaker 3: close cousins to true crabs, but different. Other animurins or
Speaker 3: false crabs include the lithodoidea or the king crabs. And
Speaker 3: the Porcelinidae, which are the porcelain crabs. And one thing
Speaker 3: animurins generally have in common is that. Okay, so these
Speaker 3: decapods all have five pairs of legs ten legs total,
Speaker 3: and in the animurans, the last pair of legs farthest
Speaker 3: away from the head is fun sized. So these animals
Speaker 3: are still decapods, but a lot of them look like
Speaker 3: they have only eight legs instead of ten, or maybe
Speaker 3: six legs and two claws. Those front legs, the chelli
Speaker 3: or the claws are legs, but in crabs they're often
Speaker 3: claw shaped, but they look like they have only eight
Speaker 3: legs instead of ten because the hindmost pair is tiny
Speaker 3: and often hidden or tucked away under another body part.
Speaker 1: Yeah, and we'll get back to this particular detail later
Speaker 1: on in our discussion. If not this episode, then perhaps
Speaker 1: the second episode.
Speaker 3: So animurans have ten legs, a lot of times it
Speaker 3: looks like they only have.
Speaker 1: Eight.
Speaker 3: Hermit crabs belong in the taxonomic superfamily Pagurroidea, and with
Speaker 3: a few exceptions, they are mostly notable for exactly what
Speaker 3: you're thinking of their dependence on externally scavenged material for
Speaker 3: armor and shelter. Usually this armor is a shell that
Speaker 3: once belonged to a gastropod, such as a snail, a periwinkle,
Speaker 3: or a whelk, though there are some animals in the
Speaker 3: family that don't need scavin shelter at all. We can
Speaker 3: talk about those in a minute, and there are a
Speaker 3: few that rely on things other than mollusk shells. One
Speaker 3: example cited in a paper that I'll get to in
Speaker 3: a minute is the discorso Pagurus schmitti, which takes up
Speaker 3: shelter not in a gastropod shell, but in empty polyheat
Speaker 3: worm tubes. The hermit crabs that do rely on external
Speaker 3: mollusk shells have bodies that are actually shaped by this need.
Speaker 3: So while true crabs have hard exoskeletons covering their entire bodies,
Speaker 3: hermit crabs have what you might call non calcified abdomens.
Speaker 3: So the front facing part of a hermit crab's body
Speaker 3: the head, the thorax, and the front pairs of legs
Speaker 3: and claws. These all have hard exoskeletal coating like any
Speaker 3: other crab, but the part of the hermit crab the
Speaker 3: abdomen in what you might call the tail or the Telson.
Speaker 3: This doesn't really resemble a crab body at all in
Speaker 3: a lot of species. It looks kind of like a
Speaker 3: curly fat worm, and it does not have a hard exoskeleton.
Speaker 3: The abdomen is flexible, soft and vulnerable. It is covered
Speaker 3: in an external coating, but it's just very thin and soft.
Speaker 3: It's very uncrab. This is the part of a hermit
Speaker 3: crab that curls up inside the externally sourced shell.
Speaker 1: Yeah, so if you're just encountering hermit crabs out in
Speaker 1: the wild, or even seeing them in a an enclosure somewhere,
Speaker 1: you're probably not going to see this part of the
Speaker 1: organism with its abdomen inside the shell. As we've been discussing,
Speaker 1: it actually walks on its second or in third pairs
Speaker 1: of legs. The first pairs are modified to form pinchers,
Speaker 1: and its fourth and fifth pairs of legs are small
Speaker 1: and specialized to grip the inside of the shell. It
Speaker 1: also has appendages called europods at the end of its
Speaker 1: abdomen to aid and securing that shell. So, you know,
Speaker 1: all these things aiding to sort of grip and hold
Speaker 1: on to that shell that it has taken on as
Speaker 1: its shelter. The larger left europod hooks the central post
Speaker 1: of a shell, and they can also use this europod
Speaker 1: to hold on to other things when they are out
Speaker 1: of the shell, Like I've read about how they can
Speaker 1: attach to say like a tree or something, and it
Speaker 1: can also use it to maintain balance.
Speaker 3: Yeah, so I think it's interesting that the hermit crab
Speaker 3: is an animal. Its body is shaped in for double purpose.
Speaker 3: So the front end of it is shaped for facing
Speaker 3: the external world. It has the chelly, it has the
Speaker 3: claws like many other crabs you would think of, but
Speaker 3: the back end of it is shaped entirely for holding
Speaker 3: on to this piece of mobile shelter. And the concept
Speaker 3: of mobile shelter, while not completely unique, is pretty unique.
Speaker 3: What makes the hermit crab interesting To read a quote
Speaker 3: from a highly cited paper on hermit crabs that I
Speaker 3: was looking at by a biologist named Brian Hazlet. The
Speaker 3: paper is called the Behavioral Ecology of Hermit Crabs. Haslet writes, quote,
Speaker 3: Many animals utilize exogenous shelters, but almost all eight hundred
Speaker 3: species of hermit crabs are mobile while sheltered, the combination
Speaker 3: of mobility and protection afforded by this lifestyle must contribute
Speaker 3: to the large numbers of these crustaceans found in virtually
Speaker 3: all marine environments as well as in tropical terrestrial shores.
Speaker 3: So Hazlit is sort of saying the hermit crab plan
Speaker 3: is a successful plan, clearly shown by the diversity of
Speaker 3: these species found all around the world. That this is
Speaker 3: a plan that works because sourcing shelter from outside the
Speaker 3: body that you can take with you when you move
Speaker 3: works really well. But it also comes with costs, and
Speaker 3: we'll talk about those costs as we go on. One
Speaker 3: thing I think to understand is that in general, while
Speaker 3: a hermit crab can leave its externally acquired shell and
Speaker 3: it can survive for some time outside of its external shell,
Speaker 3: the acquisition of a shell for external armor is not
Speaker 3: optional for a hermit crab. It's not like a nice
Speaker 3: to have. It is essential for survival in the wild,
Speaker 3: and the hermit crab's evolution has been shaped by the
Speaker 3: need for these externally sourced shells.
Speaker 1: Yeah. Yeah, this is not just somewhere it goes to
Speaker 1: sleep at night like. It has to have this with it,
Speaker 1: and if it does not have the shell, then it
Speaker 1: is highly vulnerable to predation. Exposure. It very well likely
Speaker 1: will not survive without it.
Speaker 3: Right, So I want to turn to a paper I
Speaker 3: was reading for a general overview of hermit crabs and
Speaker 3: related species. This was an overview published in the journal
Speaker 3: Current Biology called the Hermit Crabs by Mark Brifa and
Speaker 3: Sophie L. Moles in two thousand and eight. And they're
Speaker 3: going to pat the picture here of the kind of
Speaker 3: hermit crab family tree. So there are currently more than
Speaker 3: eight hundred known species of hermit crabs. Most of these
Speaker 3: species live in the ocean their marine, with a few exceptions.
Speaker 3: One is a species called Clibinarius fontic cola, and this
Speaker 3: is the only known freshwater hermit crab which lives in Vanuatu,
Speaker 3: that's a volcanic archipelago in the Pacific. And there are
Speaker 3: other freshwater and amurans, but they are not hermit crabs.
Speaker 3: So this is the one freshwater hermit crab out there.
Speaker 1: I should throw in that the hermit crabs that we
Speaker 1: were observing in the wild, I believe are the Caribbean
Speaker 1: hermit crab, and this is a variety that's common to
Speaker 1: the West Atlantic, Belize, Southern Florida, Venezuela, and the West Indies.
Speaker 3: Yes, and the ones you were observing you were saying
Speaker 3: were terrestrial or semi terrestrial, right, they spend a lot
Speaker 3: of time on land.
Speaker 1: Yeah, these were land boys. We did see one variety
Speaker 1: and I didn't identify this one one variety of aquatic
Speaker 1: hermit crab out law snorkeling. But yes, the ones that
Speaker 1: I'm mostly talking about here are hermit crabs of terrestrial
Speaker 1: hermit crabs.
Speaker 3: So there are about a dozen species of land dwelling
Speaker 3: or semi land dwelling hermit crab descendants in a family
Speaker 3: called Sinobotids. This family includes one famous species that has
Speaker 3: shed its need for an externally acquired shell altogether, and
Speaker 3: that is the coconut crab or robber crab. We've talked
Speaker 3: extensively about these before, but the coconut crab is the
Speaker 3: largest land dwelling invertebrate in the world. I can have
Speaker 3: a leg span of up to one meter and can
Speaker 3: weigh almost five kilograms or about ten pounds. They live
Speaker 3: mostly in coastal areas throughout the Indian and Pacific oceans.
Speaker 3: I think we talked a good bit about coconut crabs
Speaker 3: in our series on the Christmas Island crabs that we
Speaker 3: did several years back. This was the the animal where
Speaker 3: we were talking about the field notes of Darwin from
Speaker 3: the Voyage of the Beagle, where he's like, you know,
Speaker 3: they make really good eat and you boil the fat
Speaker 3: under their tail and it makes a quart bottle of
Speaker 3: limpid oil. And then he also tells a story about
Speaker 3: how they like locked one inside of a biscuit tin
Speaker 3: with wire and using its claws it was able to
Speaker 3: essentially like rip the tin out and escape the box.
Speaker 1: Oh man, there's a whole horror movie for you right there. Yeah,
Speaker 1: it would be Charles Darwin and crew on the Beagle
Speaker 1: having to fight off the killer coconut crab.
Speaker 3: They come and they just find the empty box. They're like,
Speaker 3: it's loose. No one knows where, you know, as long
Speaker 3: as we're throwing around.
Speaker 1: Charles Darwin quotes there's another place in the Voyage of
Speaker 1: the Beagle where he mentions hermit crabs. This is not
Speaker 1: a particularly insightful quote. It's just a mention, but I
Speaker 1: still had to drag it out. Quote. In every part
Speaker 1: art one meets hermit crabs of more than one species,
Speaker 1: carrying on their backs the shells which they have stolen
Speaker 1: from the neighboring beach stolen. And yes, there is a
Speaker 1: fair amount of shell theft as we'll get into. As
Speaker 1: long as you're thrown around quotes unrelated, I want to
Speaker 1: throw in this quote from Aristotle from the History of Animals.
Speaker 3: Is he going to tell us where they come from?
Speaker 1: Yes? Yes, you will reveal the at the time, you know.
Speaker 1: Non controversial hypothesis on crab origins quote. The hermit crab
Speaker 1: grows spontaneously out of soil and slime and finds its
Speaker 1: way into untenanted shells. As it grows, it shifts to
Speaker 1: a larger shell, as for instance, into the shell of
Speaker 1: the neartes, or of the strombus or the like, and
Speaker 1: very often into the shell of the small cirrix. After
Speaker 1: entering a new shell, it carries it about and begins
Speaker 1: again to feed, and by and by, as it grows
Speaker 1: it shifts again into another larger one.
Speaker 3: Okay, I give Aristotle half credit on this. I think
Speaker 3: he's a bit wrong on the spontaneous generation out of
Speaker 3: slime and soil, but he correctly observes the shell shifting
Speaker 3: behavior of hermit crabs, which is a major feature of
Speaker 3: hermit crabs society that we'll have to talk about later
Speaker 3: in the episode.
Speaker 1: Yeah, he's absolutely wrong on spontaneous generation. We don't ever
Speaker 1: really have to drive that home. But in a weird way,
Speaker 1: like in a very general way, the idea of like
Speaker 1: matter becomes crabs, nature becomes crabs. Maybe not that far off,
Speaker 1: as we'll discuss later on.
Speaker 3: But apart from the coconut crab, there are various other
Speaker 3: species of hermit crab that live basically would live their
Speaker 3: adult lives on land, though they still usually live out
Speaker 3: part of their life cycle in the water, with females
Speaker 3: releasing larvae into the sea, and apart from these exceptions,
Speaker 3: hermit crabs are marine species.
Speaker 1: Absolutely. We'll come back to some of the ramifications of
Speaker 1: this in a bit now.
Speaker 3: According to Brifa and Moles, there are five families of
Speaker 3: hermit crabs, and it breaks down like this. You've got pagurity,
Speaker 3: which are the right handed hermit crabs, and you've got diogeneity,
Speaker 3: which are the left handed hermit crabs right handed, left handed,
Speaker 3: What does that mean? We'll come back to that. Then
Speaker 3: you've got cenobitity, which are the land hermit crabs. You've
Speaker 3: got parapagurity, which are the deep sea hermit crabs, and
Speaker 3: you've got pilochelady, which are symmetrical hermit crabs. Though the
Speaker 3: more than eight hundred species of hermit crabs display different
Speaker 3: local adaptations and behaviors, for the most part, it seems
Speaker 3: like hermit crabs take what you can get foragers, which
Speaker 3: is true of many true crabs as well, But hermit crabs,
Speaker 3: for the most part, they will eat bits of dead
Speaker 3: organic matter, both animal and vegetable. They will eat live
Speaker 3: prey when they can catch it. Like true crabs, most
Speaker 3: hermit crabs are not very picky about food. Whatever they
Speaker 3: can get in their mouth, they're probably gonna eat.
Speaker 1: Yeah. Yeah. Both times that I was in believes there
Speaker 1: was a lot of fun to be had, especially with
Speaker 1: the kids, of leaving something out for them with permission
Speaker 1: of course, like I'm talking about the like like a
Speaker 1: cracked coconut, and then seeing the hermit crabs eventually swarm
Speaker 1: over the material.
Speaker 3: So while foraging for food is of course essential for survival,
Speaker 3: so is foraging for shelter. We will have more to
Speaker 3: say about this as we go on, but obviously a
Speaker 3: huge part of the hermit crab's survival revolves around acquiring
Speaker 3: a good shell to live in, and the majority of
Speaker 3: these shells come from As we've said, mollusks like snails,
Speaker 3: but hermit crabs don't have to fight the snail for
Speaker 3: its shell. They generally move into the shell that is
Speaker 3: left behind behind after a snail dies. Also, finding a
Speaker 3: shell is not a one time pursuit. Hermit crabs grow
Speaker 3: larger throughout their lives, which means they need to trade
Speaker 3: up for bigger shells, which can lead to very interesting
Speaker 3: mass behaviors. More on that later. One thing the authors
Speaker 3: of this overview point out is that the gastropod shell
Speaker 3: filled by a hermit crab is not only a hard
Speaker 3: surface to protect the soft part of the body, the
Speaker 3: soft abdomen, it also forms a kind of shelter against
Speaker 3: the external environment. Now what kind of shelter against the
Speaker 3: environment would a hermit crab need. One example I recall
Speaker 3: from some documentary footage I saw years ago, was the
Speaker 3: idea that a hermit crab that's on land is under
Speaker 3: the hot sun, and if it's got soft body parts
Speaker 3: exposed outside of the shell, it could quickly sort of
Speaker 3: bake and dry out without the shelter and moisture provided
Speaker 3: by a shell.
Speaker 1: Yeah, absolutely, Yeah. There again, we have to keep in
Speaker 1: mind that even they are terrestrial, they are linked inherently
Speaker 1: to the ocean, and especially when you're dealing with tropical
Speaker 1: heat environments. Yeah, they've they have to use that shell
Speaker 1: also to protect themselves and carry around some moisture.
Speaker 3: So I think it makes sense to look at a
Speaker 3: hermit crab's external shell in two different ways that both
Speaker 3: have some truth to them. On one hand, you could
Speaker 3: look at the external shell as an outsourced exoskeleton. It is,
Speaker 3: you know, it's like doing the role that would normally
Speaker 3: be done by the hard kiteness outer skeleton of a
Speaker 3: true crab. But another way to think of it is
Speaker 3: that it's like a portable burrow. And this is the
Speaker 3: point that Brian Haslitt was making in that quote I
Speaker 3: read earlier about the idea of mobile shelter. Lots of
Speaker 3: animals find holes to hide in, and rocks or other
Speaker 3: objects with recesses to provide a protective home. Hermit crabs
Speaker 3: find protective recesses that can actually come along anywhere with them. Now,
Speaker 3: I wanted to come back to the concept of ace symmetry,
Speaker 3: which we already mentioned Rob, you brought it up earlier,
Speaker 3: and it came up in the idea that there are
Speaker 3: these different families of hermit crabs, the right handed hermit crabs,
Speaker 3: the pagurady and the left handed hermit crabs. The diogeneity.
Speaker 1: Yeah, this is all very important because we think about
Speaker 1: the asymmetry of the crab in this case, and this
Speaker 1: lines up with the asymmetry of the shells that they
Speaker 1: are probably going to be inhabiting.
Speaker 3: Right, So, one thing is that hermit crabs have a
Speaker 3: directional curve in the abdomen. The abdomen can kind of
Speaker 3: curl in a spiraling direction one way or the other.
Speaker 3: But there's also an important difference in the size of
Speaker 3: the claws. And from what I could tell, it was
Speaker 3: the claw asymmetry that was primarily used to sort these
Speaker 3: animals into the different families. One claw is often bigger
Speaker 3: than the other in hermit crabs. Now, why would the
Speaker 3: animals be asymmetrical in this way. Well, so, the gastropod
Speaker 3: shells most often inhabited by hermit crabs also have right
Speaker 3: handed or left handed spirals as you're saying, Rob, and
Speaker 3: the abdomens are curled so that they fit into the
Speaker 3: chiral shell. Meanwhile, one claw is often bigger than the other,
Speaker 3: so it can function as what the authors call an operculum,
Speaker 3: which in general means a structure that closes an opening
Speaker 3: or an aperture, but in the context of gastropods like snails,
Speaker 3: it has a specific meaning. A lot of snails are
Speaker 3: able not only to retract the soft parts of their
Speaker 3: bodies into their shells when threatened, they actually have a
Speaker 3: movable hard plate that they can use to close the door,
Speaker 3: essentially to block the opening of their shell behind them
Speaker 3: after they retract, like a solid trap door. And this
Speaker 3: is the snail's operculum. And the interesting thing is it
Speaker 3: seems that hermit crabs evolved claw a symmetry at least
Speaker 3: in part to fulfill the same function as the operculum
Speaker 3: of the snails that formed the shells that the hermit
Speaker 3: crabs take over after the snails die. So Brifa and
Speaker 3: Moles right that a hermit crab can use its larger
Speaker 3: claw to close off the aperture of its shell after
Speaker 3: it retreats when threatened. And this connects to what you
Speaker 3: were talking about seeing rob where the hermit crabs, you know,
Speaker 3: they might flip over on their back and then cover
Speaker 3: up the opening of the shell with one claw, maybe
Speaker 3: the bigger claw.
Speaker 1: Yeah, exactly, Yeah, I got to see this happen so
Speaker 1: many times. It's like, imagine some sort of futuristic crab
Speaker 1: that has evolved to use abandoned human portagoons or you know,
Speaker 1: portable toilets, like you say, at concert venues as its home,
Speaker 1: and then it has eolved its larger pincher to be
Speaker 1: the exact shape needed to serve as the door of
Speaker 1: that portagon.
Speaker 3: I thought you were going to say it has evolved
Speaker 3: a claw that can say either vacant in use. I
Speaker 3: guess it would never want it to say vacant, so
Speaker 3: it says in use on its claw.
Speaker 1: Yeah. I mean, and maybe it wants people to goe.
Speaker 1: That's how you get mimics. That's exactly how to get mimics.
Speaker 3: So anyway, you end up with these asymmetries. You have
Speaker 3: right handed and left handed hermit crabs, the Pagurids and
Speaker 3: the diogenids, respectively. There are also what are known as
Speaker 3: symmetrical hermit crabs called the pilocelids, which actually do unlike
Speaker 3: the others. They have hardened exoskeletons on their abdomens, though
Speaker 3: they do still hide in burrows like in recesses in
Speaker 3: wood or rock that are thought to leave these burrows
Speaker 3: to feed. So they're related animals, but they live somewhat
Speaker 3: different lifestyles. Now we need to talk more about the
Speaker 3: selection of shells among asymmetrical hermit crabs and how that
Speaker 3: important biological need shapes hermit crab behavior and even what
Speaker 3: you might call hermit crabs society. One thing you might
Speaker 3: naturally wonder about with hermit crabs and the selection of shell,
Speaker 3: is one shell as good as the next? You know,
Speaker 3: is any shell just as good as another? And the
Speaker 3: answer is no, not at all, in multiple ways. One
Speaker 3: big factor is, of course size. A shell that is
Speaker 3: too small or too large will greatly reduce a hermit
Speaker 3: crab's fitness, and studies show that when a hermit crab's
Speaker 3: shell is too small, for one thing, it just increases mortality.
Speaker 3: Too small a shell means the hermit crab is more
Speaker 3: likely to die, but it also has less room to grow,
Speaker 3: and females with smaller shells produce fewer offspring. So it
Speaker 3: is not good for a hermit crab to have too
Speaker 3: small of a shell. However, it doesn't just want the
Speaker 3: biggest shell possible, because if the shell is too big,
Speaker 3: that increases the energy cost of carrying it. So you are,
Speaker 3: you know, massively wasting a lot of energy lugging around
Speaker 3: a shell that is heavy and too big for you.
Speaker 3: It's kind of like, I don't know, being encumbered in
Speaker 3: D and D or something. You know, you've got too
Speaker 3: much of a load. This is harming your ability to
Speaker 3: do everything else.
Speaker 1: Yeah.
Speaker 3: Absolutely, so finding a shell of just the right size
Speaker 3: is crucial, and that right size will change throughout the
Speaker 3: hermit crab's life as it grows.
Speaker 1: Yeah, so let's get into this a bit more, like
Speaker 1: it's such an important aspect of the hermit crab, and
Speaker 1: it's you know, it's the first thing we think about,
Speaker 1: but it really defines almost everything about their social interaction.
Speaker 1: And it's interesting to think about hermit crab society, or
Speaker 1: at least you know that think of them as social
Speaker 1: organisms because we call them hermit crabs, which is a
Speaker 1: bit misleading because in human history and into sort of
Speaker 1: common usage, what is a hermit hermit is someone who
Speaker 1: withdraws from society and or civilization. So it might lead
Speaker 1: you to believe that hermit crabs are also loners in
Speaker 1: a certain sense. They are, but you know, that doesn't
Speaker 1: mean that they don't have interactions with others of their kind.
Speaker 1: In fact, they have a lot of interactions, and they're
Speaker 1: very complex. So don't be too literal in thinking that
Speaker 1: a hermit crab is an actual hermit, in the same
Speaker 1: way that you wouldn't think that a king crab actually
Speaker 1: rules over decapods or something.
Speaker 3: Right, and this hue is decrees.
Speaker 1: Yeah. Yeah. As Mark e. Elidra pointed out in an
Speaker 1: article for Natural History Magazine back in I believe twenty nineteen,
Speaker 1: hermit crabs live actually highly social lives, absolutely full of drama,
Speaker 1: just way more drama than you'd expect your local human
Speaker 1: hermit to have, I'd wager.
Speaker 3: Yeah, I mean, I guess unless hermits were like constantly
Speaker 3: fighting one another to try to trade clothes.
Speaker 1: Yeah, or a pillar. You know, if you have your
Speaker 1: your pillar, develloers, it'd be like, no, I want the
Speaker 1: I want the taller pillar.
Speaker 3: Yeah, I'm gonna do exactly. I'm going to bang my
Speaker 3: pillar on your pillar until you give me your pillar,
Speaker 3: unless I decide I want my old pillar back.
Speaker 1: So the various dramas that they encounter and instigate, includes,
Speaker 1: but is not limited to, according to Eldra, commotion of
Speaker 1: social aggregations, intergenerational inheritance of homes, life or death, competitive struggles.
Speaker 1: So the author points out that in contrast to a
Speaker 1: lot of other social organisms you might think about, terrestrial
Speaker 1: hermit crabs socialize with non relatives, and this is crazy
Speaker 1: to think about. The reason, he points out, is that
Speaker 1: while they spend most of their lives on land, we're
Speaker 1: talking about terrestrial hermit crabs again, not the aquatic ones.
Speaker 1: They spend most of their lives on land, but they
Speaker 1: are born in the sea. That's where the larva larvae
Speaker 1: are released. They become mixed in the ocean, and then
Speaker 1: they land on far flung shores via the tides. So
Speaker 1: I want to read this quote from Eldra. He says, quote,
Speaker 1: By the time an immature crab first arrives on land,
Speaker 1: it is therefore far away from any of its relatives,
Speaker 1: encountering instead only an assortment of non kin. Moreover, because
Speaker 1: the abundance of terrestrial hermit crabs on shore stretches of
Speaker 1: beach often measures in the hundreds of thousands or even
Speaker 1: the millions. Each crab is but a stranger within a
Speaker 1: vast crowd.
Speaker 3: However, you know, if you think of a human analogy,
Speaker 3: imagine a bunch of very selfish humans are thrown into
Speaker 3: a mix of you know, they're all living together beside
Speaker 3: one another, and not amongst their kin, just amongst strangers.
Speaker 3: And you know, maybe imagine they're not very they're not
Speaker 3: very nice people, they're not very inclined to be helpful
Speaker 3: to others. They still might find reasons to hang out
Speaker 3: around one another, even if they're mostly selfish. And one
Speaker 3: of those reasons might be the need for trade or
Speaker 3: an economy of sorts exactly.
Speaker 1: And what are they going to have an economy of
Speaker 1: sorts about, Well, it's going to be the shell, of course.
Speaker 1: I also like how this idea it kind of matches
Speaker 1: up with the you know, the huge stereotype that one
Speaker 1: encounters of big city life, particularly in movies from like
Speaker 1: the seventies and I guess into the eighties as well,
Speaker 1: Like nobody's related to each other in the city. You
Speaker 1: go to the city, it's just everybody's for themselves. You're
Speaker 1: gonna you're gonna lose your shell in that big city.
Speaker 1: I guess it's kind of kind of that way with
Speaker 1: the crabs here. But anyway, the shells that they use,
Speaker 1: like you've been saying, yeah, these are scavenged from dead mollusks,
Speaker 1: but this is also key. Uh, they have been remodeled.
Speaker 1: These are remodeled homes. Elidra points out. Uh, the crabs
Speaker 1: you when they have when they have a fresh shell
Speaker 1: that is going to like this is okay, something has died,
Speaker 1: as the snail has dyed, and now I'm going to
Speaker 1: make this shell into a home. You can't just put
Speaker 1: it on and wear it out. Uh no, No, you
Speaker 1: need to use chemical secretions to weaken the shells calcium carbonate,
Speaker 1: as well as additional physical sculpting via your appendages. You're
Speaker 1: going to change the shell into something that absolutely suits
Speaker 1: you and absolutely suits your purposes. Right.
Speaker 3: So this is another way in which one shell is
Speaker 3: not necessarily as good as any other. Size matters a lot,
Speaker 3: which is a sort of inherent feature of the shell,
Speaker 3: but also the the remodeling condition of the shell matters
Speaker 3: a lot. There are shells that have been recently renovated,
Speaker 3: and that's much more desirable than a shell that is
Speaker 3: a real fixer upper.
Speaker 1: Right, right, And this is unique to terrestrial hermit crabs,
Speaker 1: and we'll get it more into why in a second.
Speaker 1: But yeah, as Lighter points out, it's absolutely necessary for
Speaker 1: terrestrial hermes because they can't depend on water buoyancy to
Speaker 1: help them carry that shell around. It's just the basic
Speaker 1: reality of living out of the water, and some of
Speaker 1: these shells can be quite hefty for the crab, and
Speaker 1: so by reducing the shell mass, they're lowering the energy
Speaker 1: cost of just traveling across land, and they do a
Speaker 1: lot of traveling. Additionally, shell remodeling increases the internal space
Speaker 1: in the shell, allowing not only more room for the crab,
Speaker 1: but more room for increased water reserves to keep the
Speaker 1: organism from drying out. Like we mentioned earlier, the importance
Speaker 1: of this being a way to help them sustain themselves
Speaker 1: when they are living times in very hot environments. He
Speaker 1: also points out that while aquatic hermit crabs would conceivably
Speaker 1: benefit from shell remodeling as well, because you know, even
Speaker 1: though you have buoyancy, lighter shells could still be a benefit, right,
Speaker 1: more internal space could still be a benefit. However, aquatic
Speaker 1: hermit crabs have to contend with shell expert predators in
Speaker 1: the ocean, organisms that are highly evolved to bypass shell protections. Therefore,
Speaker 1: it would be a mistake to sacrifice any of your
Speaker 1: shell's protection in order to get any of these benefits. Meanwhile,
Speaker 1: on land, the terrestrial hermit crabs have far fewer shell
Speaker 1: specialists to contend with, and lighter points to various research
Speaker 1: that shown that like your average predator that would be
Speaker 1: messing with a hermit crab is just not going to
Speaker 1: have like the bite power or the not going to
Speaker 1: have the tools necessary to crack open even a partially degraded,
Speaker 1: a partially remodeled hermit crab chosen shell. Now, Joe I
Speaker 1: included a photo. This is from Lydra's paper and an
Speaker 1: example of an unmodified versus a modified shell. The central
Speaker 1: axis is often removed, but the shell again retains protection
Speaker 1: against the bite strength of terrestrial predators.
Speaker 3: Yeah, and one thing you can see in this picture
Speaker 3: is that a lot of the effort in the remodeling
Speaker 3: seems to be focused on the interior of the shells,
Speaker 3: sort of like expanding the interior cavity and making more
Speaker 3: room there and smoothing it out.
Speaker 1: Yeah, and certainly, you know, removing some of the additional
Speaker 1: protection of the shell. But again it's apparently not going
Speaker 1: to matter for terrestrial variants now. Like we said, one
Speaker 1: of the huge factors in hermit crab societies is of
Speaker 1: course the need for these shells and the fact that
Speaker 1: as the crab grows and molts, they'll need to abandon
Speaker 1: smaller shells in favor of larger shells. And as Lidra
Speaker 1: points out, there's some really interesting about all of this quote.
Speaker 1: Over time, remodeled shells have come to dominate the housing
Speaker 1: market of terrestrial hermit crabs. Exhaustively sampling these housing markets,
Speaker 1: I have found few unremodeled shells, and also few shells
Speaker 1: that are still in the process of being remodeled. Most
Speaker 1: shells have already been completely remodeled. Remodeled shells present a
Speaker 1: superior home, and as with any superior resource, it is
Speaker 1: understandable that terrestrial hermit crabs should prefer remodeled shells over
Speaker 1: unremodeled shells. However, over evolutionary time, a mere preference has
Speaker 1: transformed into an absolute dependence. As remodeled shells accumulated, terrestrial
Speaker 1: hermit crabs came to specialize in living in them, to
Speaker 1: the point that life in unremodeled shells became nearly impossible.
Speaker 1: My field experiments revealed that after an early life stage,
Speaker 1: most terrestrial hermit crabs cannot survive in unremodeled shells for
Speaker 1: even a single day.
Speaker 3: Wow, Okay, I did not realize that.
Speaker 1: Yeah, yeah, because you know what's the current hermit crab
Speaker 1: to do? If you need a shell, Well, you could
Speaker 1: remodel your own shell technically, but most crabs simply can't
Speaker 1: do this anymore, in large part because they end up
Speaker 1: too big to access the inner parts of a fresh shell.
Speaker 1: So only the smallest immature hermit crabs actually can get
Speaker 1: in there and do this, which paradoxically often means that
Speaker 1: they're left with oversized shells. But as such, all terrestrial
Speaker 1: hermit crab individuals highly prefer a remodeled shell over a
Speaker 1: fresh one. Even if they can fit inside that fresh
Speaker 1: shell and conceivably remodel it and make it their own,
Speaker 1: remodeling the shell is still a last resort. Ledra stresses
Speaker 1: that this is this is the only factor that ensures
Speaker 1: the continued creation of remodeled shells. That some hermit crabs
Speaker 1: are going to be put in a position where they
Speaker 1: have no choice, wow, because I mean they can do
Speaker 1: other things to it should not like a hermit crab
Speaker 1: is left without any thing and there, and we'll touch
Speaker 1: on how this occurs. In a moment. They may use
Speaker 1: something like a bottle cap and that might buy them
Speaker 1: a little time, but they need a shell. The thing is,
Speaker 1: you don't just find many emptied remodeled shells. He points
Speaker 1: out that on a given beach, the only empty remodeled
Speaker 1: shells you're likely to find are the ones that have
Speaker 1: been physically compromised in one way or another, so like
Speaker 1: they're they're broken, they don't actually protect the hermit crab anymore,
Speaker 1: or they're clogged with a rock something like that, they're
Speaker 1: no longer functional. The competition for remodeled shells is intense,
Speaker 1: and they're just you're just not going to As a
Speaker 1: hermit crab, you are not going to find them out
Speaker 1: there unless you're extremely lucky. As such, hermit crabs have
Speaker 1: to remain vigilant at all times, always looking out for
Speaker 1: a bigger shell, because either you need one or you're
Speaker 1: about to need one, so you need to always be looking.
Speaker 1: And also you have to be peeking over your shoulder
Speaker 1: because there's probably someone eyeing your shell, that is looking
Speaker 1: for a slightly bigger shell, and they're trying to decide
Speaker 1: if it's worth trying to take it from you.
Speaker 3: Right, So this leads to the fact that hermit crabs
Speaker 3: very often get into well, I guess there's some debate
Speaker 3: over how exactly to characterize these encounters, whether they are
Speaker 3: purely agonistic fights, or whether you might consider them in
Speaker 3: some way a kind of trade or negotiation. Maybe we
Speaker 3: can talk about that some more in the next episode.
Speaker 3: But they get into these encounters that lead to shell swapping.
Speaker 1: Yeah, they're at the very least aggressive negotiations. Yeah, but
Speaker 1: so I'll continue to categorize them as battles. But yeah,
Speaker 1: give with that caveat in mind. Basically, what seems to
Speaker 1: be happening is one crab will attempt to flip the
Speaker 1: other on its back and force its opponent out of
Speaker 1: their shell. But as Lijra points out, this kind of
Speaker 1: thing can last hours and it might just end in
Speaker 1: a stalemate. It might just end in everyone just going
Speaker 1: home or carrying on with the shell they had two
Speaker 1: hours ago. And that alone, I think that's pretty fascinating.
Speaker 1: Most animal competitions and struggles are fascinating, but it's the
Speaker 1: onlookers that make this even more interesting. Leider writes, quote.
Speaker 1: As bystanders gather at the site, and as the moment
Speaker 1: of evictioneers order emerges out of the chaos of commotion
Speaker 1: in the aggregation, the crabs array themselves literally into a line,
Speaker 1: each holding the shell of the crab ahead of it.
Speaker 1: This social formation emanates from the pair of antagonists, with
Speaker 1: the line of crabs there after being size ordered from
Speaker 1: biggest to smallest unquote. Because if a crab is forced
Speaker 1: to give up its shell, the winner will leave its shell,
Speaker 1: and this will set off what's called a vacancy chain.
Speaker 1: All of the onlookers will have a shot at leveling
Speaker 1: up their current shell situation to a new one that
Speaker 1: is slightly bigger.
Speaker 3: You can find video of this online. By the way,
Speaker 3: there are multiple documentaries that have captured versions of this,
Speaker 3: and it's amazing to see they literally do just organize
Speaker 3: themselves in a size ordered line where they're each grasping
Speaker 3: the shell of the slightly bigger one, like feeling around
Speaker 3: on it, trying to make sure that it's what they want.
Speaker 3: Because the whole process, by the way of in which
Speaker 3: Hermit crabs assess a shell for the qualities they want
Speaker 3: is interesting on its own. There seem to be some
Speaker 3: visual processes going on. They you know, look at a
Speaker 3: shell to assess from a distance whether it's something they
Speaker 3: would want. But that's never enough. They have to inspect
Speaker 3: it physically. They like feel all over it with their
Speaker 3: antennae and their chelly, you know, the claws and the legs.
Speaker 3: And then usually they will want to sort of like
Speaker 3: dip into it with their legs and maybe they're abdomen
Speaker 3: to see if they fit right, and they may end
Speaker 3: up changing their mind and wanting to go back to
Speaker 3: the previous shell, though obviously that could be a tricky
Speaker 3: thing if a bencha, Yeah, hermit crabs are lined up
Speaker 3: all trying to level up at the same time. It
Speaker 3: is an amazing thing to see.
Speaker 1: Yeah, to your point about like sizing up the shell,
Speaker 1: trying it on. Like, sometimes you have a situation where
Speaker 1: you remember the asymmetry of shells and hermit crabs here,
Speaker 1: and sometimes you have a you have like a like
Speaker 1: what a left handed crab trying to get into a
Speaker 1: right handed shell or vice versa, And and that's going
Speaker 1: to be a situation where the crab is going to
Speaker 1: quickly realize this does not fit, this is not the
Speaker 1: shell I want to live. We may come back with
Speaker 1: more details on that regarding the left right handedness and
Speaker 1: hermit crabs and shells. Now, Elidra again points out that
Speaker 1: all this competition is based again not on kinship, but
Speaker 1: on selfishness and competition. And he has this wonderful part
Speaker 1: in the paper where he says that it's what's kind
Speaker 1: of the antithesis of something like a US social ant,
Speaker 1: you know, where all the ants and a call in
Speaker 1: the ark, and they work together to ensure the success
Speaker 1: of the colony, the success of their genetic line. But
Speaker 1: that is not the case with the hermit crab. And
Speaker 1: Leidra writes the following quote. If in an alternative world,
Speaker 1: interactions in terrestrial hermit crabs were among close kin rather
Speaker 1: than strangers, then the crabs social lives might be different,
Speaker 1: with individuals potentially being more interested in bequeathing their finest
Speaker 1: shell to a close relative than in stealing the coveted
Speaker 1: shell of a stranger. Now, there have been plenty of
Speaker 1: other researchers and also science journalists and writers and so
Speaker 1: forth that have commented on all of this. Elizabeth Preston
Speaker 1: wrote all about this topic for The New York Times
Speaker 1: in twenty nineteen in an article titled, even hermit crabs
Speaker 1: have wealth inequality. This was based on a twenty twenty study.
Speaker 1: This is because the New York Times paper came out
Speaker 1: a month before the twenty twenty study. This was in
Speaker 1: a December publication, so that's why the dates would seem
Speaker 1: to be in the wrong order here. But that particular
Speaker 1: paper was a comparison of wealth inequality in humans and
Speaker 1: non humans by Chase at all. This was a study that,
Speaker 1: as I recall, received a fair amount of mainstream attention
Speaker 1: at the time because, of course, wealth inequality is always
Speaker 1: a topic of interest among human beings, and crabs are
Speaker 1: inherently interesting. You can throw hermit crabs into any study
Speaker 1: and it's going to be fascinating, even if there's not
Speaker 1: really connective tissue there.
Speaker 3: Well, is there connective tissue here?
Speaker 1: To a certain extent, it seems to okay, I mean so,
Speaker 1: in the study, Chase and his co authors gathered around
Speaker 1: three hundred hermit crabs on Long Island Beach and took
Speaker 1: away all their shells, which, okay for science, I will
Speaker 1: allow this, but you know, obviously I can't help it
Speaker 1: sympathize because this is literally all these crabs care about.
Speaker 1: The researchers weighed and measured the various shells, and then
Speaker 1: they considered how they were distributed across the sample population
Speaker 1: of hermit crab. And this is a quote here from
Speaker 1: that article by Preston quote. The distribution curve they found
Speaker 1: peaked around medium sized shells, then dropped as the shells
Speaker 1: got larger, before tapering off very gradually through the largest
Speaker 1: shells of all this matches the shape of wealth distribution
Speaker 1: curves in many human societies, so it's interesting. But at
Speaker 1: the same time, the New York Times article of citing
Speaker 1: anthropologists Monique Molder, points out that we shouldn't get two
Speaker 1: carried away comparing hermit crabs to humans in this scenario, because,
Speaker 1: first of all, there are plenty of other factors involved
Speaker 1: in human inequality. You know, it's one of those it's
Speaker 1: often described as a wicked problem. You know, it's complex
Speaker 1: enough that you can't just point to necessarily there are
Speaker 1: certainly large factors, but there are multiple factors. And Molder here,
Speaker 1: who again as an anthropologist, speculated that vacancy chains are
Speaker 1: probably also not the only factor in terrestrial hermit crabs
Speaker 1: as well. I mean, you know, there are other factors
Speaker 1: as well into how they are dealing with each other,
Speaker 1: even on the the basis of their shells. Still, you know,
Speaker 1: we can't help but compare ourselves to the hermit crabs. Again,
Speaker 1: part of it is just that hermit crabs are that interesting,
Speaker 1: and we as human beings are that self absorbed. What
Speaker 1: we can't help but see ourselves in the crabs. We
Speaker 1: can help what anthropomorphize the crabs, and you know, especially
Speaker 1: when we see them, you know, in a very complex fashion,
Speaker 1: struggle over limited resources like this. That again, I think
Speaker 1: if you're just casually aware of hermit crabs, you might
Speaker 1: not realize that just any shell, it's not a situation
Speaker 1: where any shell will do, and it is a situation
Speaker 1: where the shells have been augmented, and therefore it's competition
Speaker 1: not just for random garbage left over by dead snails,
Speaker 1: it's competition for mostly previously augmented shells, like the products
Speaker 1: of a hermit crab civilization, if you will.
Speaker 3: Well, that's funny if you think of it as like
Speaker 3: more fighting over fighting over a limited pool of finished
Speaker 3: goods rather than creating new goods. It's almost like a
Speaker 3: human post apocalyptic scenario exactly. Yeah, it's kind of mad Max.
Speaker 1: It's kind of Fallout right. It reminds me that in
Speaker 1: at least some of the Fallout games you do encounter
Speaker 1: a giant hermit crab that is using what some sort
Speaker 1: of like a bus or something like a school bus
Speaker 1: for it's uh, it's abdomen. I can't remember offhand, but
Speaker 1: I remember when I would when I would play the
Speaker 1: most recent Fallout game, I would occasionally encounter that that
Speaker 1: creature and yeah, yeah, I mean it's it's it's interesting.
Speaker 1: Where are they getting all these school buses? What are
Speaker 1: they changing about? I guess they're taking all the seats out?
Speaker 3: Yeah, is it a right handed bus or a left
Speaker 3: handed bus?
Speaker 1: I don't know. Yeah, And are they sizing up from
Speaker 1: different buses? Like they start with a like a shorter bus,
Speaker 1: then they go to a full sized school bus, and
Speaker 1: they're going to like a megabus. Then it's a double
Speaker 1: decker bus. Those are only that's only in Fallout London propertly,
Speaker 1: But you know, uh, you could go wild with with
Speaker 1: the scenario.
Speaker 3: Well, hey, we've got more hermit crab stuff to talk about,
Speaker 3: So join us again next time.
Speaker 1: That's right, we have some more content lined up regarding
Speaker 1: the hermit crabs. We're going to fish around for a
Speaker 1: bit more. Because I'm a hermit crabs. There's a lot
Speaker 1: of research out there. That's one of the reasons I
Speaker 1: felt pretty secure in going in and discussing them again,
Speaker 1: even though we've discussed them in the past, because there's
Speaker 1: constantly new hermit crab research coming out and there are
Speaker 1: some remaining mysteries and controversies about hermit crabs. So we'll
Speaker 1: get into all of that in the next episode. In
Speaker 1: the meantime, we'll remind you that Stuff to Blow Your
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Speaker 3: Huge thanks as always to our excellent audio producer JJ Posway.
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