From the Vault: Crabs Eat Everything Around Me, Part 1

your Mind. My name is Robert Lamb and I'm Joe McCormick. And today we're gonna be talking about crabs. I think this will be the first episode in a in a series that we're doing here at least two parts to this, because the crabs are ravenous and we're gonna be talking all about crabs eating things. You know, this is kind of a holiday tradition for so I figured how many years ago it was that we did uh, we did

Christmas Crabs. We talked about the Crabs of Christmas Island as our Christmas episode, and and so it feels appropriate that as we enter into the holiday season here with in November and December, that we should return to the world of crabs and the feasts that crabs engage in. Have you ever noticed how the crabs come earlier every year? At least it feels that way. But yes, anyway that this will be a feast day of an episode because it will all be about crabs feasting sometimes things feasting

on crabs, mostly what crabs themselves feast on. It's funny how crabs are are a natural source of feasting related content. Uh, Rob, I I think you saw my note about this beforehand, but I discovered the strangest Google results phenomenon before we came in here. What I found out earlier today was that when I do a Google search for crabs, it's five letter word crabs. You'd think the first result would be what like Wikipedia page for this animal, but no,

the first result is seafood restaurants featuring crabs. They're trying to sell me some crab legs and drawn butter. And then the second result is the is like a health node about pubic lice. And then finally the third thing in the result is about the actual animals, the decapod crustaceans. Well, um, after you mentioned this, I had to try it out for myself. And and granted I'm not going in like fresh,

you know, I do use Google quite a bit um. Uh. So for me, when I did a search for crabs c R A B s um, the number one hit is sponsored seafood content, but then it's the wiki for the decapod crustaceans, and then it's pubic lice in number at number three um, and then it's more pubic lice, and then it's some stuff about the crab nebula I think video content about the crab nebula uh, and then it's back to pubic lice once more, before rounding out

page one search results with the Britannica dot com article about decapod crustaceans. Okay, so as our top three go basically, Google just thinks I'm going to be more interested in uh in in the lice than you are. I have no idea. I mean it could. I mean we were both probably searching for crabs all morning um and and

perhaps yeah days before as well. So it seems like, I mean, I don't know how these algorithms work, but it seems like they would have gotten into their robotic minds that these are gentlemen who are interested in decapod crustaceans, and we should serve them up even more of it. Guy, I don't know, it's all mysteries in there. Who knows the mind of the machine crabs that that order all those results for us? Um, But I wanted to come

back to uh this uh image in amber. So there's a study that was just published in Science Advances earlier this year by Javier lukeway at All, and it was called Crab and Amber reveals an early colonization of non

marine environments during the Cretaceous. So this discovery concerns a fossil found in a piece of amber mind in modern day me and Mar dating back roughly a hundred million years or so, so squarely in the middle of the Cretaceous period, containing a remarkably well preserved specimen of a crab bearing the author's note, large compound eyes, delicate mouthparts, and even gills. Basically it's wholly intact. The whole thing is in there. Yeah, it's quite impressive looking in the

way that it is um its body. It's position too, it looks like it is like throwing up its clause and a defensive position that we've all seen. And I think or you haven't seen it in person, you've probably seen a picture of it, of a crab like on the beach saying stand back, mammal, do not make me

pinch you. Um. So it's as if, through you know, across uh, this is vast stretch of time, the crab is warning us to stay back with such ferocity that the very forces of geology like conspired to preserve this this uh, this ants it's doing. And yeah, maybe I maybe I sound silly, but I give this image five out of five coal hods. I am profoundly stirred by this crab trapped in amber. And and not just because it you know, it looks like that haunting mosquito and

amber prop from Jurassic Park. But but there's something a little bit more to this too, because it raises these questions like how did a crabred million years ago get stuck in tree resin to become part of a fossilized piece of amber. We don't know the answer to this, but the researchers hypothesized, well, maybe this was a crab that lived a partially arboreal lifestyle. There are crabs today that climb trees as part of their lifestyle. So maybe

this crab was climbing trees for some reason. Uh and uh, and and maybe it's also just because it causes you to realize that crabs existed and we're already beginning to come out of the oceans to move inland from the beaches hundred million years ago when dinosaurs were at their apex. And I always love those realization moments where you have like, oh, yes, animals of this kind and this kind actually did live alongside one another, terrestrial dinosaurs and terrestrial or semi terrestrial crabs.

And Robert, I think you'll be very familiar with the the the did they fight mindset. Right as soon as you imagine that, the my sort of like eight year old boys brain starts going, did they ever fight each other? Dinosaurs versus crabs? I don't know how much of a fight that would have been, but I guess more more relevantly I could say, did they ever eat one another?

And Uh, you actually gotta give you credit because you turned up the source on this for the copper Light study that found a pretty good case that yes, at least the eating was going one way. Yeah, but the details of this I was surprised at because you know not not to say that that some like smaller you know, beach combing dinosaur wasn't also hunting and gobbling up crabs. But the evidence here points to a different mode of consumption, right.

So this is a study published in Scientific Reports in The lead author was a professor Karen Chin, who is Curator of Paleontology at Colorado University Boulders Museum of Natural History. And uh so this was by by Chin, Feldman and Tashman called Consumption of Crustaceans by mega herbivorous Dinosaurs, dietary flexibility and Dinosaur life history Strategies. So this is a copper light study, and you've gotta love a copper light study. Copper light, of course, is fossilized animal dung. This is

dung that has become a mineral of the Earth. And the top line on this is that, uh collections of fossilized dinosaur feces from seventy five million years ago found in modern day Montana revealed that some giant herbivorous dinosaurs

weren't always strictly herbivorous. Now, this would not be the first time a subject like this has come up on the show before, I think It was in our episodes on the Minotaur that we talked about evidence of bovines, cows and bulls and related animals sometimes eating flesh and in addition to their mostly vegetable diets. But it looks like maybe something similar was going on with giant herbivorous dinosaurs. So these feces probably belonged to hadrosaurs or the duck

build dinosaurs. And it looks from the contents of these copper lights like these giant herbivores sometimes would supplement their vegetable diets by eating rotten wood and crustaceans. You can tell by these, uh, these remains preserved in the fossilized dung which are full of wood, fiber and crustacean shells. Now, again, this this raises these wonderful questions like how did this happen? Why?

And you could imagine it's possibly some kind of accident, maybe a duckbill dinosaurs eating a rotten log for some reason, trying to get some kind of nutrients from all this rough rotten wood, and the rotten log just happens to be full of crabs. But to come back against that, against the accident hypothesis, I just want to read briefly

from the press release describing this study. Quote, the size of the crustacean shell bits in the copper lights indicate the crustaceans were at least two inches in length and perhaps larger. Uh. And this is according to the lead author, Karen Chin. Individual crustaceans comprised from twenty six of the width of a common had restored beak, suggesting it was

unlikely that crustaceans were unwittingly swallowed. Uh So, the ideas, it looks like whatever these crustaceans were, maybe they were crabs. We don't know for sure what they were, but there have been fossilized crab claws found from around the same area and going back even further in time, So there

were crabs around these station. Shells could have belonged to crabs that were smashed up too much in the in the copper light to know for sure, but they could have been crabs, and they would have been big enough that it kind of seems unlikely they just accidentally went into the hadrosaur's mouth. It seems like the hadrosaur would

kind of have to choose to eat the crab. Yeah, I mean, I'm also For me, it just makes me wonder, like what was the digestive system of a hydrosaur, Like it was just it seems like an industrial processing plant. You know, it's just rotten wood. Uh, it's all these these are these these fairly large like whole crustaceans and or their shells embedded in it, and you just you

just eat that down because you're still hungry. And it may not have been about just obtaining raw calories like they may have been searching for a specific nutrient like we see in some other cases of otherwise herbivorous animals sometimes eating say bones or something where they're looking out certain types of minerals, maybe calcium or something. It could have been the case that maybe eating eating crustaceans like crabs for the drsaurs was linked to the reproductive cycle.

They may have been seeking to bulk up on calcium or something. We don't know though, but oh whatever the answer there, I just I love it. So mega herbivorous or so called herbivorous dinosaurs eating crabs or crab like crustaceans seventy five million years ago and crabs a hundred million years ago getting frozen in amber for all of time. Uh, it just it just fills my you know, I got butterflies under my skin, all over my limbs. It's like, this makes me so happy. Yeah, I mean for the crabs.

Though this is just another couple of pages in the history of the crab planet, well right, because it all it raises the question going the other way, the one we're saying we didn't know if we could answer. But so it looks like some dinosaurs in some cases eight crabs or crab like animals, other crustaceans. But the other question would be did crabs ever eat dinosaurs? I don't know about you. I could not find anything, any evidence

to directly address that question. As far as I know, there is no physical evidence anybody's aware of, uh, to settle this issue. But I would say, if we can't find an answer to the question based on everything else we're going to talk about in the series, I think I would argue that in the absence of any evidence,

our default assumption should be yes. I believe so. I think based on what we know about the nature of crabs in general and the sort of things they do eat, it it only makes sense that that they would they would partake of dinosaur meat if they came across it in their environment Alright, well, I say from here on out, for the rest of the series, we're just going to be looking at crabs eating all kinds of stuff. So, uh so, rob if you're ready, let's let's begin the

crab feast. Yeah. But like just like with human feast, it's not enough to know what you're going to be eating. It's it's also about how you're going to eat. Uh, you know that, So we should we should probably start there with how crabs go about, uh consuming their various feasts. Right. So, crabs are of course a verse subgroup of the order of decapod crustaceans, So the decapod as in having ten feet, they are crustaceans. So there, you know, creatures with an exoskeleton.

In order to grow bigger, they have to molt, so they have to shed their hard exoskeleton and come out with a soft one while they can rapidly increase in size and then reharden that. Crabs of course live in all kinds of environments. They originally come from the ocean, but over time and evolutionary history, like we saw with the crab preserved in amber, they started to move out away from the ocean and eventually into freshwater environments, and

there are even land crabs. So as to the question of how and what do crabs normally consume, well, there are a lot of different species of crabs, and some of them have different dietary specialization, so there's no one answer to that question. But if you just want to sort of be general overall, it seems like the majority

of crabs are not especially picky. Uh. Many crabs appear to be omnivorous opportunists who will eat pretty much anything they can shove into their mouths, and this can include everything from vegetation just gobbling up algae and fresh plant material leaf litter to uh to eating meat of course, scavenging scavenging carry in which crabs do a lot, or just getting little bits of organic or animal detritus, to actively hunting live prey with their claws, which some crabs

do so as to diet. Crabs are all over the map. But the next thing I wanted to mention this was new information to me when when I was getting ready

for this episode. So animal bodies, you know, they've usually got some kind of special equipment to help them extract the maximum amount of nutritional value from their food, and this often involves either chemically or mechanically breaking down the food from its original form, often to increase the surface area or the ease of access to nutrients by the digestive system, So there might be some kind of chemical breakdown as well. So you know, you know, you know

the equipment. You've got Humans have teeth that we chew with and that that mashes food up and increased surface area. You've got gastric acid secreted by the cells in the lining of your stomach. But then you know they're all kinds of other strategies. Spiders will vomit digestive enzymes over and into their prey to uh sort of reduce the nutritious parts down to a fluid or mush that they can then slurp up with the mouth. And they also do have a form of chewing with their jaws, which

are called chillissory. But crabs have one of the most glorious digestive aids I think I've ever read about. So if you ask the question do crabs have teeth, I think the answer would have to be yes and no in a couple of ways. So Obviously, crabs do not have teeth like us. Uh. They typically eat first by using their claws to tear food into small chunks before bringing it up to their mouth parts, and then they

usually have a number of different moving mouth parts. These consist of um these things called maxilla heads, also known as jaw legs, which are sort of like hands within the mouth. These are are modified a little leg parts that will sort of grab bits of food and pass them inward and onward to other parts of the mouth known as the mac silly and the mandibles, which can further shred the food apart into smaller pieces that can

be swallowed. But then once the food is swallowed, it is inside the digestive system where the most amazing feature appears, and it's this. Crabs, along with other related crustaceans, have an organ known as a gastric mill, which is more or less teeth inside the stomach. They've got gut teeth. They can chew with the insides of their stomachs, And

this is another one that really got me. This is also worth googling some pictures of if you can, because there there are some uh some photos you can find on the Internet of like gastric mills, how having been extracted from the inside of a of a crabs digestive system, and they it's hard to describe how they look. They've they've got the kind of they're like a semi translucent pinkish orange, uh sci fi weapon hood. I don't know it's but it's also kind of beak like. It's very unnerving.

I think, what are the interesting things about about the way of crab eats? And especially as evident if you're watching, um it's a close up video of a crab eating, is that there even more so with other creatures this there's this sense of meticulous um disassembly. Uh, the crab is not so much I mean, it is consuming, but it is also just uh just taking whatever it is consuming completely apart. It is disassembling matter and putting it

into itself. Well, yeah, the crab makes you think about how much how much humans actually need to use tools for the kind of disassembly that they do leading into into eating say meat or something you know, like so humans devote a huge amount of their tech know logical energy over the history of time into creating like tools for butchery of food, cutting food into smaller and smaller pieces that are manageable that you can bite into, chew up,

and all that. The crab they've they've got their disassembly tools right there on their body. They've got the claws, they've got the maxilly and the mandibles, and then once the food's inside, they've got additional opportunities for chewing. You don't have to stop chewing once you have swallowed. So the way the gastrit mill works is that it's sort of choose the food from inside the stomach by grinding it between these hard parts like plates or surfaces that

are moved around by powerful gut muscles. And so while I was reading about the gastrit mill, I came across a really interesting piece of research from twenty nineteen that I just had to mention as as we're going along here, and this was by Jennifer R. A. Taylor, Maya S. Devrees, and Damian O Alias published in the Proceedings of the Royal Society be In in nineteen called Growling from the Gut co Optation of the gastric mill for Acoustic communication

in ghost Crabs. So the short version of this discovery is that you've got this animal, the ghost crab scientific names quadrata, and it will sometimes make a threatening sound by way of having evolved. Quote a novel stridulation apparatus on the clause that is used during agonistic interactions. So, strigulation is any sound that is made by an animal rubbing pieces of its skeleton or exoskeleton together. The very common example you can think of is the sounds made

by crickets or grasshoppers. That's strigulation. They rub parts of their legs or their carapists together, and that makes this chirping sound that is useful to the animal for some reason, maybe for maybe for mating, or maybe as warning signals or something. The ghost crab appears to use this stridge relation of rubbing its claws as a as a warning sign, as signs like Hey, I'm threatened, I am dangerous. I've got these big claws. You do not want to get

near me. But in addition to the strigulation they make with their with their claws, to quote from the abstract of this paper, by a tailor at all quote, but they also produce a rasping sound without their claw apparatus. We investigated the nature of these sounds and show that oh quadrata adopted a unique and redundant mode of sound production by co opting the gastric mill the grinding teeth

of the fore gut. Acoustic characteristics of the sound are consistent with strigulation and are produced by both male and female crabs during aggressive interactions. Uh so, yes they are. Actually they can like chirp like a cricket with the grinding teeth inside their stomachs in order to have a redundant way of making this aggressive sound display that they

when they're being threatened. And the authors actually speculate as to why they would have this redundancy why be able to make this sound with two different parts of their body? They write, quote, A key advantage of using gastrixtrigulation over the claw apparatus is that it provides signal while freeing up the chel a for postural display and attack readiness.

So you know, basically this this allows you to have claws out to be maximally visually threatening and maybe maximally dangerous if a fight actually does start, while still making the grinding scary sound. So yes, anyway, crabs and related crustaceans gastric mills. The chewing doesn't have to stop once you go down the gullet. And like we said, a lot of crabs are not very picky eaters, So who knows, maybe maybe if you could be taken apart into small

enough pieces, you would go down the gullet. Than I guess from here we're going to start getting into the various meals of the crabs. You know, what do they use this uh, this fabulous uh equipment for? And I guess that I was thinking that one of the best places to start would be talking about crabs eating humans, because obviously that's going to be one of the most pressing questions to us the humans, right. Uh, Sure it eats, but will it eat me? How delicious am I? Do

I deserve to be eaten by crabs? Um? And I think it's an understandable question. I mean, on one hand, like we are concerned with with this question with any creature on some level, you know, we have to have that that that that box checked off or or empty? Will it eat me? Uh? Is it incapable of eating me? Does it want to eat me? Uh? These are always questions that we have about other creatures in the animal kingdom and the various horror movies and animal creature flicks

that we uh we watch. They don't help matters either, because, on one hand, we have our giant crab movies in which giant crabs, you know, in addition to occasionally wanting to take over the world or destroy whole cities, they want to grab people with their claws and either try to eat them, or it's implied that that crab is grabbing you because it wants to eat you, or, in the case of Attack of the Crab Monsters by Roger Corman, not just eat you but also absorb your soul and

intelligence in so doing. Right, But then, uh, we also have countless movies in which we see crabs scavenging, uh, you know, crawling around on the corpses of humans who have probably been dispatched by some kind of slasher or some sort of monster that it itself that it that is not concerned with eating the human. Uh. This is like a standard scene. And oh goodness, I was trying to think of specific examples, and I couldn't come up with one. But I know I've seen it over and

over again. Like cut from the you have a dark scene with something spooky happening, an attack is um is shown or implied, and then it's daylight and cops are discovering a body and their crabs on it. I can think of two examples. One is in Joy Laws after the initial tack attack at the beginning, when they discover the body of the first victim on the beach, their crabs everywhere, and it makes the police sound sick. Um.

Second one is an even better movie. It is I Know What You Did Last Summer, in which there's a part where the nineties teen slasher movie where Jennifer Lovehwood finds a body in the trunk of her car. She did not put it there. I think she's being messed with by a killer and it's covered in crabs that are presumably scavenging it. So yeah, and I think there are various other films. I thought I've seen a Jellow film where they're there there crabs on a body. It's

just it makes sense. They're discovering a body, put some crabs on it, um and uh, and it'll make it a little a little creepier um. And then it it. You know, it does, because it's like this person is not only dead, but now they are the domain of the crabs. Um. So in thinking about this, though, it reminded me of a bit of Um. I guess it's folk wisdom that I learned from my mother in law, uh, and that is, don't eat crabs after hurricane. Have you

ever heard this before, Joe? I think maybe you and I have talked about this off Mike, maybe, Okay, because I was. I was looking around for more on this online, and I found some sort of echoes of it, but I did not find enough on it that made me satisfied that this is not something that just originated with my mother in law or her family, or like, you know, a local area that like her parents were in or something.

But I'll continue to discuss it here and certainly if anyone out there has heard the same thing or is privy to the same folk wisdom and has some insight into why it is, uh, well, obviously we would love to hear from you. But the notion here seems to be, uh that, Okay, those crabs in the wake of a hurricane, they have been feasting on the flesh of people who died in the storm, and therefore they should be avoided.

I can understand that. Yeah, yeah, I mean it's I guess a lot of it comes down to the idea that if these crabs have been eating humans and we eat those crabs, it's kind of cannibalism by proxy, right, Yeah, And generally we don't eat like a lot of even if we're eating meat, we're not eating carnivores, or we're not eating animals that are that are eating a lot of meat. We tend to consume herbivores. Yeah. Well, I mean if you're eating seafoods, you're probably eating a lot

of cars. Well yes, yes, the seafood for sure. But yeah, but I also I did find some just looking around, I saw some people like asking and some of these like question websites saying is it okay to eat? Like they were kind of applying the same concern to just see life in general, like should I be concerned that the fish that I'm eating might have themselves eating human flesh? Well that's a sticky idea, they'll get in your head. Yeah. Yeah. So I decided to look into it a bit more.

And I was looking. First of all, I was looking at a few different sources in uh. They included Coastal Angler magazine and also additions of the Sun Sentinel. Um. And so it's worth remembering that hurricanes are destructive not only the humans and human civilization, but they also impact marine environments. This can result in extra dead sea life in the water, and that includes crabs. And this can often be due to um reduced dissolved oxygen in the water,

rapid salinity changes, and violence surf. And this can certainly impact crabbing as a human enterprise, either by damaging the equipment that's necessary for crabbing or disrupting key crabbing locations. And this applies to other organisms as well. Um. It can you know, be especially rough on oyster seed grounds for instance. And as far as oysters go, the other key issues related to hurricanes and other storms is flood runoff from the mainland carrying various chemicals into their environment.

And as oysters or filter feeders, they can pick up those chemicals um and that can then be composed a danger to human means consuming those oysters. Uh. And of course there are other potential risks involved with eating raw shellfish as well, But as far as I can tell,

this doesn't really impact crabs so much. Um. But I wanted to look a little bit more about the you know, the idea of of corpse eating crabs First of all, I wanted to sort of check my my assumptions on this and and find out, well it is as true or am I just sort of learning this from movies?

Do crabs want to eat human bodies? Um? And And luckily you know, there's a lot of material out there in the world of forensics UM in biology UM, human corps in water may be set upon by fish, water, rats, crabs, um, various other creatures. According to UM. One paper was looking at by zerin er Call and Urdum Hoskuler in post mortem animal attacks on human corpses came out and so this applies to shallow water as well as deep water, where crabs will uh may even gnaw the bones that

they find down there. Wow, now apparently some crabs are going to be more indiscriminate than others. So yeah, yes, you know, we have to be careful we talk about crabs because if there's not just one type of crab there, they are multitude, and they all have different strategies and

different environments and different temperaments. UM. I believe blue crabs in particular are often observed to scavenge human flesh band and that probably has to do again with like environments in which law enforcement or finding bodies and bodies are retrieved and uh, and that's gonna happen to be the same environment where the blue crabs are active. Another type of crab that we've talked about on the show before, the coconut crab. Uh. They seem to generally be game

for for anything. So it seems like a safe assumption to say that, yes, you've you've given the opportunity. The coconut crab would feast on human flesh as well, But as for other species, I would say, check with your local crab. I don't know if they want to eat you or not. UM, And a lot of it's gonna depend on are you where that crab is, what is that crab normally and so forth. Now, I was also looking at an article title Decomposition and Invertebrate Colonization of

Cadavers in Coastal marine Environments by GAYL. S Anderson from two thousand and nine, and in this the author points out that um in saltwater environments, crabs, crayfish, and barnacles are generally the most important arthropods from a forensics point of view, and they point out that crabs, especially we'll

we'll just get right in there. They'll go for the facial flesh and the eyes, the open orifices of the face are I mean, just think about this practically, Joe, don't to like, if you're gonna start munching on a human, Uh, all those holes in the face, that's just a great place to get started, you know. Yeah, that's the that's like the oysters on a chicken. Yeah, so that's that's generally where they start. But once they get going, apparently

they can rapidly d flesh a body. Um. I was looking around to see if I could find some hard numbers on that because I know a lot of times it is of key interest in forensics. Um, you know, Okay, animals will do this to a body, Scavengers will do this to a body. How long does it take for them to do it? Because then we can time the you know, the death of of this particular individual, or we can time when their body entered this environment. I could not find any any time. That doesn't mean they're

not out there. So if you know those, if you haven't to have like a you know, some sort of study that involves a stop watch, a human cadaver and a whole bunch of blue crabs, then send it my way. I would look to take a look at it. Do your personal eco friendly funeral plans involve crabs crab burial? I mean, why not? Why not? So I want to come back to the question. Okay, uh So, First of all, okay, I think we can say it's safe to say that

crabs definitely will de flesh the human form um. Now, as for this idea of there being something bad about eating those crabs after they have tasted human flesh, um, again, I think there is a sort of superstitious view there, and there's perhaps this you know, revulsion of the idea that you might eat something that has eaten people, and then you know, to some extent you are engaging in cannibalism by proxy. Now, where this gets interesting, though, is

when you start looking at the subject of cholera and crabs. Um, Joe, had you ever uh were you privy did any of this information before? No? I mean cholera And I know cholera is typically a water borne illness that has spread through contamination of water sources by infected people. Yeah, yeah, and uh, and so when you think about cholera, you tend to think about. You didn't think about a sewage. You think about you know, you know, poor water treatment,

water sources, that sort of thing. UM. But apparently crabs and UH and some other shellfish can also UH be a means of acquiring cholera. Now as and I was looking around him mostly mostly when we're talking about this,

we're talking about UH some some particular situations. And there have been particular outbreaks that have been linked to the consumption of crabs that that are infected with cholera um, or at least they have cholera like clinging to the bacterium, clinging to their their shells, UH, to the hard parts

of their body. For instance, there was an outbreak in nine in coastal Louisiana and it was blamed on improper storage or cooking of crab the crab and the crab and in questions seem to have have you know, the cholera bacterium clinging to it. Apparently there was a similar

case in Texas UH previous decades. I was able to find some news footage from the late seventies from like from Louisiana Public television where they were talking about this UH, and it was quite interesting because you know, it was it was a big deal. There were a lot of questions like, Okay, what's happening here, Why did these crabs have cholera? Why are people you know, what's going on? And then there was concern over how is it gonna

impact the crabbing industry and just people's lives in general. Um, and uh, yeah, it was quite interesting because you know, to be clear, cholera is generally we think about it as a as a human situation. You know, this is

where you you find the cholera. Cholra are pathogenic to humans. UM, So they're not actually you know, infecting uh, the crustaceans in question here, but it would be a situation of them being in waters infected uh, that that are tainted by cholera or potentially and this seems to be like a less firm point. It seems like potentially if you had these crabs coming in contact with the bodies of humans that had cholera, they could partitually get it that way.

But it seems like for the most part we're talking about just water that is say, tainted by untreated sewage, and and you have people in the population that had cholera contributing to said sewage. I see, So it seems like moral of the story is definitely properly cook your your your seafood. Yes, definitely, that's that's that's a proper storage, proper cooking. Um. And that seemed to be the main

point they were getting to in this situation. I believe based on some of the follow up information was looking at from the CDC, it seems like this had to do with UM with with the with pollution of the water, either due to some sort of a sewage situation, sewage treatment, or sewage run off from something else, potentially something linked

to U two ships UM but um. Looking also at the CDC, they point out, quote, brackish and marine waters are the natural environment for the ideologic agents of cholera H Vibrio colorad UH zero group zero one or zero one three nine. There are no known animal hosts for Vibrio colorade. However, the bacteria attached themselves easily to chitten containing shells of crabs, shrimps, and other shellfish, which can be a source for human infections when eating raw or undercooked. Now,

I know what you're saying. You're you're probably thinking to yourself, well, that still doesn't answer the question can can Does that mean you can catch cholera from a crab that eighty human being with coolera? I'm still I'm still not sure. I don't but but I don't think any of the evidence is pointing to that being like the primary way that you would get sick from, uh, you know, for meeting a crab, or that has anything to do with with concerns over eating crabs post hurricane. So I'm not sure.

I'm not sure. I can't ask my mother in law anymore about this, but I have this suspicion that perhaps it's kind of a kind of like a Cajun stew of like maybe a little bit of folklore in there. Also maybe a little bit uh, left over stemming from this late seventies um, you know, fear about cholera and the crabs. Uh, and you know, perhaps some other stuff to on in there as well, um uh. And also maybe she was just you know, messing with me. Yeah nothing.

Maybe that's familiar with the ways of the of coastal Louisiana and so forth. Well, I mean, I would say, whatever the base of this, uh, this piece of advice or folk wisdom is, I would say that it's probably always going to be different. I mean, unless you're in some kind of like farmed bond villain scenario, it's always going to be difficult to know whether or not a crab that you have actually acquired to eat like what

it has been eating in its past. Yeah. I mean, you just never really know if it had eaten a part of a human or not. But the odds are probably against it. Yeah. Yeah. And um, and in terms of other crab and just crabs in general, like eating humans, like another area to get into as well, would a crab kill a human and eat it? And uh, this

does come up from time to time. I think there was you know, largely you know, unproven and to a certain extent at least discredited theory that coconut crabs consume to aviator Amelia Earhart, or at least consumed her remains

after she crashed. Um. Again, I don't think there's any proof for this, and and I don't know that anyone is actually arguing that the crab crabs would have killed her, but um uh, you you know, it's one of those things where you can make any kind of argument for Okay, what if somebody was sufficiently injured and then crabs came upon them. Could the crabs deal the killing blow? Could the crabs be the one to finish you off? And I guess it's like with the dinosaurs, like could have

Could crabs kill a dinosaur? Well, I guess so if they had enough of an advantage, uh, you know, if the if the prey was severely weakened. Um, But I don't know. It seems kind of pointless to to worry about this too much. I mean not to be insulting, but a crab is not really a particularly analytical creature, so I don't think it could size us up and figure out what part of the body it needed to

attack in order to finish us off. We are not part of a crab abs like natural uh you know, habituated diet, so I don't think it would have instincts about what part of the body to attack to finish us off. So I would say, if a crab attacks the human is probably just randomly pinching at whatever parts of the body it can get at. So my guess would be that it would be very unlikely for even the most powerful crabs, even your coconut crabs, to to

really initiate a successful deadly attack on a human. But there is something about maybe it comes back to that defensive display of the crab. It's so impressive, even though it's small, uh, that it just reverberates through the human psyche and takes on the form of say, crabs attacking hercules and myth or crabs rising up against humanity in Roger Corman films. And so we just get it just

shows how effective that display is. We're like, we we know that crabs not actually gonna come over here and and and whoop us uh, but but it takes on these, uh, these enormous forms in our mind mind right, I mean, the the rasp of the gastric mill does not lie. There's no reason to go messing around with that thing,

putting your fingers into its pinchers and stuff. But I am generally curious though, So if anyone out there again, if you've heard anything about this, um, this bit of a folk wisdom that you shouldn't eat crabs after a hurricane, or that eating crabs that of eating humans is is is somehow specifically a bad idea. Uh, fill me in. I would love to know more before we move on. I just wanted to say about the coconut crabs thing.

I had also come across that people supposedly claiming that that Amelia Earhart was eaten by coconut crabs, really without any evidence to say that. I think people were just kind of guessing, oh, what if this happened. Um. But but that did make me think back on on Charles Darwin's comments about how coconut crabs actually being delicious and under their tails having that big mass of fat which turned into wonderful limpid oil. Remember that, Oh yes, I

do remember that. Yeah, you know, this reminds me was I was looking around, um, you know, doing various searches on fatalities related to coconut crabs, and I did find, um, I think a couple that occurred. Uh. And but they didn't have anything to do with crabs attacking people. They had to do with the coconut crabs haven't eaten something that contained a toxin and then when that crab was consumed by humans resulted in fatality. Oh, that would make sense.

So I think, oh, yeah, ultimately crabs dupos the greatest risk to human beings in the form of you know, of of tainted food, of one sort or another, but that can be that can be said for a lot of things. It's as with our past Thanksgiving episodes on dangerous foods. Um, you know, any kind of if food is cooked improperly or stored improperly, prepared improperly. Um, you know,

it's it's pretty easy to get into dangerous zone. Oh yeah, I mean one of the points we made repeatedly in that series is if you're actually just like tallying up edge cases, all kinds of strange things can seem very dangerous. You know, Uh, improperly washed, packaged greens, bottles of peanut butter and all kinds of stuff. Yeah, I mean, I'll go ahead and throw this out there. Don't try and eat um a live crab hole. I think you're probably going to hurt yourself. May have to go to the

hut of the hospital over that. Yeah, don't go for the had restore Crudeau. Yeah, alright. The next example of the next course in the crab Feast I wanted to talk about is, uh, maybe the I can't remember for sure. This may have been the thing I was reading about

that gave me the idea to do this episode. Um, And this is one where you can actually watch the video I'm about to talk about yourself, because the subject here is a field recording that was uploaded by the Monterey Bay Aquarium Research Institute or in Bari, originally captured in two thousand eleven. You can find it on their YouTube channel now. And this took place on an expedition

led by a researcher named Peter Brewer. So the team here was investigating oil seeps and methane hydrates along the seafloor off the coast of British Columbia. Again, this was back in two thousand eleven, so this would have been on in the ocean off the west coast of Canada. And methane hydrates are a very strange and fascinating phenomenon. I again didn't know a lot about them before I started researching for this episode, and this has really captured

my mind. So these are essentially chunks of solid icy material containing large amounts of methane alongside regular water molecules. So it's got methane gas or H four, which is

a naturally forming hydro hydrocarbon. Methane is the primary constituent of so called natural gas, as well as being a byproduct of bacterial decomposition of organic matter that gets buried down in the sediment at the bottom of the ocean, and pockets of natural gas underneath the modern sea floor, or just generally any methane content in the sediment or

the or the bedrock below the ocean. Sometimes the methane in these pockets get exposed so that gas can escape up through little holes or rifts in the in the sea floor and float away. But sometimes, under the right conditions, methane that escapes from these pockets does not just float away. Sometimes, because of very high pressure at the bottom of the water column and extreme cold in the deep ocean, the methane gas becomes trapped along with water ice in chunks

of this strange frozen solid. These are methane hydrates, and to be clear, the name is a little bit misleading because methane hydrates are actually not a new chemical compound joining water molecules and methane molecules with chemical bonds. Rather, methane hydrates are what's known in chemistry technically as a class rate, which is a composite in which you've got

molecules of one kind of substance. In this case, methane that are physically trapped within the crystal structure of another type of substance, in this case water ice, so little molecules of methane stuck within a lattice structure of water ice. And because of this unusual structure, methane hydrates can make a literally flammable ice. So you can have a big chunk of this stuff. It looked pretty much like regular ice. You can set it in a dish on a table, but if you hold a match up to it, this

is ice which will catch on fire and burn. And for this reason, methane hydrates are sometimes called fire ice. Now it's generally believed today that large amounts of solid methane hydrates lie buried in formations underneath the sea floor all around the world, though there's debate about exactly how much.

According to a range I found given on a page by the U S Department of Energy, Fossil Energy and Carbon Management site, there could be anywhere from two hundred and fifty thousand trillion cubic feet of methane locked up in hydrates around the world, from that two hundred fifty all the way up to seven hundred thousand trillion cubic feet, and these hydrates contain a really dense concentration of hydrocarbons.

A claim I've seen cited in a number of sources is that one cubic meter of methane hydrate would typically contain a hundred and sixty four cubic meters of methane gas, So a very small volume of this solid material, this icy stuff, the hydrate, if disrupted, will potentially release a ton of gas, which, of course is one reason that methane hydrates have people who think about climate change a little bit can cerned, because it seems that there is

actually a significant amount of potential greenhouse gases that could be released into the atmosphere locked up in these solid icy forms, and if something causes these solids to melt, a lot more stuff can be released into the atmosphere. But anyway, so these methane hydrates exist in these you know, rocky icy formations under the sea floor, but they can also form spontaneously when methane and very cold water mix under high pressure, like at the bottom of the ocean.

So coming back to this video, I was talking about the video captured by the Monterey Bay Aquarium Research Institute team in two thousand eleven. So they were doing a survey for of these methane hydrates and oil seeps at a depth of about one thousand, two hundred and sixty meters, and the team came across a rift in the sea floor that was producing this steady little trickle of bubbles

rising towards the surface. And while the researchers were looking at the stream of bubbles, suddenly, hey, here comes a crab. It just there's a crab coming into frame, and the narrator of the video suggests that the crab may have been attracted by the pulsing in the water column at the side of the gas bend. But whatever the reason, this crab comes ambling over. It's walking along the bottom, and then it comes right up to the hole in the ocean floor that the bubbles are coming out of.

And then, in the first of a series of real awe buddy moments, it reaches out at the stream of bubbles with its claws. It's trying to grab them, very like you know, dog dog chasing its tail behavior. Presumably it thinks that the movement in the water indicates some kind of potential prey or other food source, and you see it repeatedly lunge at the bubble tower with its claws, but of course there's nothing to grab, so it just

sort of hugs the bubble jet several times. But then from here things start geting weirder, because again, what are these bubbles their methane and what can potentially happen to methane at this depth and temperature When mixed with water, it can turn into methane hydrates. So the narrator of this video explains that the methane gas bubbles rapidly form into solid pieces of methane hydrate as they stick to the crabs for limbs, so it's you know, reaching out

to grab the methane bubbles. It thinks their food. Then they the bubbles are freezing into a coating of fire ice on this crabs clause and then trying to explain what happens next, the narrator of this video hypothesizes that the chemical reaction that transforms the methane gas into these solid chunks of methane hydrate uh quote may have given the sensation of something slightly warm and mushy. Uh So, I guess this is just supposition on on the researchers part.

But maybe what they're suggesting here is that the crab thing, oh, I've got some kind of potentially delicious organic goo, maybe from a dead whale carcass or something, and it's all over my claws. Now, so of course, when in doubt try it out, you know, better eat it and see

if it's good. So the crab begins to try to eat the methane hydrate off of its own claws, and this goes very poorly because the hydrate essentially freezes the crabs mouth parts or mandibles, which reminds me of that thing where you know, you stick your tongue to a frozen flagpole, like in that Christmas movie, except I guess here the flagpole would be like stuck to your own mouth and it would be coming along with you. And the narrator of the video actually describes it as quote

a milk mustache of solid hydrate. Well, now I'm beginning I'm growing worried for this crab. This that is that this has really taken a turn. I know, it went from like kind of cute and bumbling to like, oh no, what's going to happen to this crab's mouth? Uh? And

apparently the crab does whatever it's feeling. It does not like it at all, So it starts it's trying to use its claws to remove the frozen methane coating from its mouth, and you can see it's scraping at the solid white mass of hydrate with the tips of its of its claws while shedding flakes of it into the surrounding water. And unfortunately, I do not know the answer to the question did the crab ever get its mouth on frozen I I hope so, but the researchers do

not have an answer to offer on this subject. On the pessimistic side, the narrator claims that pure methane hydrate is twenty times harder than regular water ice, though I couldn't find independent corroboration of that fact. But on the plus side, that like you can see in the video that the crab is doing a decent job scraping pieces of it off, Like you can see the flakes just coming off and floating up into the water. So I'm gonna say with crabs, many things are possible, maybe all

things are possible. And I'm gonna say that it really just it. It scraped and scraped and scraped with those uh, those spiny tips until until it got its mouth parts free and went on to di scavenge many a human corpse.

But anyway, I mean, so this is on top of being just a strange and interesting example of a crab eating something that was not food, because you know, I think anybody who has a dog will recognize that a lot of animals have the impulse of like if if something is ambiguously presenting as maybe food, might as well put it in the mouth and give it a try.

But on top of that, it also shows an interesting thing that we don't usually think about being land levers, which is the role of naturally forming hydrocarbons as a part of the environment that animals would have to interact

with every day. You know, on on the sea floor, there were actually all kinds of ways that organisms regularly interact with I don't know what you might call you know, the constituents of the deep earth, uh, from from the ecosystems that form around hydrothermal vents to these weird interactions between animals and methane hydrates from under the under the ground or under the sea floor. Obviously, for the crab in this video, this was at least a very uh

frustrating and unfortunate random encounter. But some animals actually have a much closer and more dedicated evolutionary relationship with these same substances. With deep sea hydrates gas hydrates like methane hydrate, they're actually marine biological communities that appear in some way

to depend on methane hydrates for their energy needs. And just one example I wanted to mention I found described in a paper from published in the year two thousand and uh nat your viscin sho often um by a cr fisher at all called methane ice worms hesio ska methanicicola colonizing fossil fuel reserves and rob, I've got an image for you to look at while I described this here.

But so in this case, the story behind this discovery was that a bunch of researchers were conducting an exploratory dive with a miniature submarine in the Gulf of Mexico along the sea floor at a depth of fivetys. I guess this was in the late nineties sometime, and they came across a large gas hydrate, a chunk of this stuff, the fire ice that was They said about one meter thick and two meters in diameter, and they said it

had recently breached the sea floor. So I guess this has been this had been some subsurface for a long time, and for some reason it had recently been you know, berthed up from the bottom of the ocean and was now exposed. And this was a big, old chunk of

this stuff. And then the authors write in their abstract quote two distinct color bands of hydrate were present in the same mound, and the entire exposed surface of the hydrate was infested with two to four centimeter long worms, since described as an new species, and they said the density of the worms reached individuals for every square meter. So this was a previously unknown type of polycyte worm that appeared to make a habitat out of these gas hydrates.

It was originally called uh hesio ska methanic cola. I think now it has a different name. I think now the genus is uh sears so s i r s o e so sears so methanic cola uh So. This would obviously raise the question, if you live around gas hydrates at the bottom of the ocean, what do you eat? How do you make a living well. Tissue samples were consistent with the worms acquiring nutrition from a chemo autotrophic organism.

That would mean an organism that makes its own energy by consuming geologic chemicals rather than than by sunlight like a photosynthetic organism would. And the authors in this study weren't able to prove anything conclusive Lee, but they hypothesized that these worms, these new worms, were surviving by eating chemosynthetic bacteria that colonized the surface of the gas hydrates.

So there would be bacteria that that form mats on the surface of these frozen methane hydrates that would metabolize chemicals contained within them in order for the bacteria to survive, and then the worms would eat the bacterial mats. And then the author's right quote, the activities of the polykeets grazing on the hydrate bacteria and supplying oxygen to their habitats appears to contribute to the dissolution of hydrates in

surface sediments. So I guess this would be one thing that explains how these hydrates disappear over time once they're exposed on the bottom of the ocean. But rob I've also attached to an image for you to look at. That's uh, I believe this is a micrograph close up of the face of one of these polykeet worms that lives on the hydrate. It is absolutely terrifying. It looks like some sort of a dark destroyer unleashed from a shadows.

It has a kind of bristling fuzziness, which you would think would make it a little more cuddly, but actually makes it worse. Yeah, though those fibers are not for cuddling, you can tell. And it looks like it has this enormous mouth to like just suck down dreams. Very very true. And yeah, it's mouth, I would say it's mouth actually looks like if you ever see those um endoscopic images of of the larynx or the voice box. Yeah, it also reminds me it has the mouth of some of

the more terrifying muppets. I think you know where their mouth is kind of articulated bad, Yes, like the the hippiup aliens that has that kind of thing going on. Oh god, the Hippiepps are so evil. All right, Well, I think we're gonna have to call it right there for part one, but we will definitely be back next time to continue the crab feast. What will happen when crabs put other things in their mouths while their mouths freeze? Will they find it delicious? Um? You'll just have to

tune in to find out. The world is a buffet and the customers or crabs all right? Uh? In the meantime, yes, certainly right in let us know where your thoughts are in the crabs that we discussed in this episode. Um. But in the meantime you can find other episodes of Stuff to Blow your Mind in the Stuff to Blow Your Mind podcast feed which you will find wherever you get your podcasts. On Tuesdays and Thursdays we have core

episodes of Stuff to Blow your Mind. On Monday's we have listener mail, On Wednesdays we have artifact episodes, and on Friday we have Weird How Cinema. That's our time to set aside most serious concerns and talk about a weird movie. Huge thanks as always to our wonderful audio

producer Seth Nicholas Johnson. If you would like to get in touch with us with feedback on this episode or any other, to suggest a topic for the future, just to say hello, you can email us at contact at Stuff to Blow Your Mind dot com Stuff to Blow Your Mind is production of I heart Radio. For more podcasts for my heart Radio, visit the i heart Radio app, Apple Podcasts, or wherever you're listening to your favorite shows.