Animals That Eat Poop

of American Thanksgiving. It's a time when people eat too much, and they eat a lot of gray and brownish foods that are too rich. They probably shouldn't be eating all of this stuff, but they do anyway. So it's a perfect time to talk about poop eating. Cram down the gullet with loving care, uh, in the presence of one's family and and in laws and all that. Now, before anybody turns us off, I do want to drive home that most of what we're gonna be talking about in

this episode, UH relates to animals eating poop. As the title of the episode implies. At the very end, when when everyone's ready, we may talk a little bit about humans, but first we will deal with animals before we deal with the added complexities of human beings. Now, I'm sure the listeners out there are wondering the same thing I was. So I got back from vacation to find you super excited about animals eating poop, and I was like, well,

what got you going on this, Robert? Why did you fling yourself headlong into a pit of coprophagia for the week of Thanksgiving? Well? I originally had the idea to do it after watching a David Attenborough narrated special titled Spy in the Pod, which is fun. It's a fun little show in which they have a remote control robot it's hanging out with elephants, and they briefly cover coprophagia practiced by elephant calves, which we'll get to in this episode.

And I thought, well, that's interesting that a new spin on something that I'd largely just dismissed as being essentially an act of both of human defilement but also abnormal animal behavior. And I thought, well, this sounds like kind of a grim top kip topic, but certainly thanksgiving us the time to do it. Um. I think we've talked about what like poisonous foods and stuff like that. Yeah, it kind of fits in with what we've done and were those aren't we Yeah, yeah, it's just running at

least two and three Saturday. Yeah, but but anyway, anyway, and looking into the topic, then I realized, oh, this is a fascinating topic. And in the grand tradition of our episodes on cannibalism, h b clity, and necrophilia, I think that there's a there's an awesome challenge in tackling something like this, something that is generally considered very abnormal behavior for humans, and looking at it from just the the boiled down, no nonsense, uh animal side of things,

like what is it? How does it make sense within the realm of animal biology and behavior, and then how might what might we apply that to the human scenario even Yeah, the sort of like brute chemical energy realities and and uh microbiological ecology of the world. In in that kind of context, poop eating begins to come into

focus as a beautiful thing. Yeah, you know, as I discussed in our our Halloween two thousand and eighteen episode Horror Anthology, Volume one, UM, there's an episode of Night Gallery in which a character is tricked into believing himself cursed to an irreversible transformation into a human earthwork, and it's Leslie Nielsen with an iPad like shooting at walls. Yeah, the a man with no fear who has eventually overcome

with fear of becoming a worm. And I said that one of the reasons we find this concept so horrifying

is that it reduces us to our alimentary track. We fear the worm at the heart of our being, and I think that we see that reflected in this episode as well, in thing that kind of reduces us to just our digestive system tends to have an inn aid horror to us because we're definitely going to be touching on the microbiome and all of this the importance of gut bacteria, which continuing research tells us just is far more important than than we ever imagined in the past.

I mean, the worm dictates much of our health and even our mind. Yeah. We might get into this more as the episode goes on, but it is so fascinating that we have, uh, such a such a deep disgust and revulsion for the products of the human digestive system. Yeah, And it is just it's I mean, a certain amount of it is is learned for sure. But I think part of it too is that we're just we're not a coprophegic species, so we do not engage in this uh routinely or is a part of of normal behavior.

I mean really, in the grand scheme of things, we're weird for not doing it. While we tend to look at it the other way. We we if we see an animal consuming its own poop or the poop of another creature, we think all of that is grotesque, how inhuman of this non human creature. Well, just think about the sensory difference, Like the world must just look and smell very different. If poop is delicious to you, or or even without even getting into idea of it's delicious

or not, but if it is, under any circumstances nutritional. Yeah, so it really turns things on its head. But let's talk about some of the reasons, like the basic reasons that excrement consumption might be desirable for an animal before we get into species specific examples. Sure, well, one is obviously going to be that feces contain nutrients. I mean, by the time they come out of you, you have not gotten all the possible nutrition from it. That's right.

Given digestive system does the best it can to break down the nutrients it needs from a meal, and then it passes on the rest. But sometimes it can't digest everything of value in there, and this may require the creature itself or another scavenger to give all or part of the excrement a second pass, maybe even a third pass, who knows. And also you have to consider the different

species require different kinds of nutrients. So what might not be all that useful to you, or you might possess an excess in order to excrete in waste might be something that is very useful to a different organism. Yeah, and two other points here too that certainly we'll get into examples of are that that first of all, you definitely think of you can think of that poop sometimes as a as a first draft. You know, not everything is finished, not everything has been been harvested. And then

also think about what the human digestive system does. It takes the energy in the form of plant and or flesh, and it transforms that into a form that can be absorbed and digested, and it doesn't all take place like in your throat. You know, it's it's taking place at at at various points throughout a given creatures digestive system. Now that the next big reason, of course, relates to the microbiome. Yes, and this is huge. It's just sort of coming into focus, I think in in the past

few decades, how enormously important the microbiome is. How your gut flora is. It determines a lot about how your body works and who you are, right and the gut floor is reflected not only in what's going on inside of you, but also in what is coming out of you. So you know, we we don't like to think of ourselves as a worm, obviously, and we don't like to think of ourselves as an organism at all. But if we do, we tend to think of ourselves as a

single organism, splendid, perfect ape. I am an animal, I am one thing. Yeah, I'm the animal even But of course there's more to us than all of that. We're a multi cellular construction of maddening complexity, and we're literally host to an ecological community of commencial, synthiotic, and pathogenic micro organisms. We're learning more and more about the role

that our microbiome plays every day. Certainly but it certainly plays an important role in digestion, and one microbiome can make certain diets more advantageous, and when out of balance, can lead to illness. So, for an extreme example, and one that I think ties in nicely with today's episode, just can consider uh, fecal microbiotic transplants f m t s. This was all over the news and you know, comedians

had a big time with it. Sounds crazy, Yeah, Like I feel like it certainly sounded crazy years ago, but less so today. I feel like at this point, everybody's kind of like, oh, yeah, that that that makes sense. They're gonna be situations where the microbiome needs to be restored, and to do so, a fecal transplant is sometimes the answer. But what's crazy is this, to a very large extent, is an example of the modern Is it basically the modern medical version of exactly what some animals are doing

when they consume feces. We just have more elegant uh and uh, you know, modern delivery system in place. If you want a more palatable analogy, just think about all of the commercials for probiotic yogurt and stuff. Yeah, exactly, this is the probiotic yogurt. Of the animal world. They can't go and uh and and and buy something at their local grocery store. Uh. They have a more old

fashioned and effective means of taking care of the scenario. Now, these cases we've been talking about, our cases where it's clearly part of an animal's natural life cycle to consume feces to get something that it needs, whether that is living microbes or some kind of nutrients. But there are also probably cases where coprophagia is a sign that something is wrong, right, I mean, animals and captivity may engage

in coprophagia. Puppy male dogs, for instance, can learn to confuse dog food with feces due to the horrid conditions in which they are sometimes raised. Adult elephants may engage in it due to captivity issues, and certainly, as we may touch on at the very end of the episode, humans may engage in such behavior due to dementia. But again,

human coprophagia is is very rare with the animals. I feel like, once once we take into account the cases where it makes sense and is a part of their natural behavior, even the unnatural cases make a little bit more sense, you know, because with the human if a

human consumes of feces. It is a human doing something that does not make sense within uh at any other point in humans life, whereas a dog a puppy, say, eating feces is is doing something perhaps out of place or out of in a frequency that doesn't sit well with their natural behavior, but is not unheard of in

their natural behavior. Well, maybe we should talk about the idea of coprophasia as a natural behavior of dogs, because I so I can't speak directly to coprophasia, but I go out walking my dog and it is clear to me, based on the directions that the dog pulls, that feces are incredibly interesting to him. He's very interested in getting up close to them. I've never let him linger there with enough time to see what he would do if

the smelling were allowed to evolve into munching. I don't know if that would happen, but I've often suspected now there could be other stuff going on there. For one thing, I think feces probably a lot of these feces are dog feces, and they probably contain a lot of interesting sensory information smell wise, like he can learn about the other dogs in the area by smelling the poop, I

would assume, I mean probably just food interest. Yeah. I mean it's worth remembering that dogs live in an entirely different sense world in regard to smell. Yeah. But but I also do wonder like, Okay, if I wasn't there to pull him away, to gently drag him back on the leash, would he eat these feces? Well? I certainly no other dog owners who have to deal with, say the dog trying to get into get at the cat litter, Yes, to eat cat feces, yes, for example, And we're we're

about to touch on that as well. Uh. I feel like this is probably the example of coprophasia that that our listeners are most well acquainted with um because dogs are popular pets and they do engage in this kind of behavior from time to time. And I mentioned it can be quite disruptive of the sort of anthropomorphizing we

often do with our pets. Right, we teach them like we treat them like little fur babies, and if the names, yeah, and if and even the food we pick out the artificial uh, I mean the the prepackaged of food that we purchase for our animals. I mean those are foods that are marketed to appeal to both dogs but also to humans, where the humans are like, yeah, that's the kind of thing that I would eat if I were

a dog. And so the idea then of of of consuming cat feces is generally kind of repugnant, and we have to I'm I'm I'm guessing there probably comes a point in any kind of like dog ownership. I mean, I feel like there's certainly that point in cat ownership to where you you really have to to remind yourself, oh, yeah, this is an animal, and it's and it's living in a strange environment by hanging out in my house all

or most of the time. But so when coprophigia occurs in dogs, I guess there are a couple of questions we could ask. First is how common is it? And second is why are they doing that? So, first of all, it is a minority of dogs that eat poop, but not a tiny minority. Aeen study in the journal Veterinary Medicine and Science by Heart at All used a large survey of dog owners to look at specifically that the question was about dogs eating dog feces. This study is

not about dogs just eating poop in general. Maybe other animals, and it found the following. About seventy seven percent of dog owners had never seen their dog eating poop, about twenty three percent had seen their dog eating poop at least once, and about sixteen percent had seen their dog eating poops six or more times, so about a quarter try it at least once within view of a human.

Roughly one in six dogs seem to eat poop a lot, and the lead author on that study was a veterinarian named Benjamin Hart, who directs the Center for Animal Behavior You See, Davis. One thing you might notice if you

google like why is my dog eating poop? Is you'll get websites of self proclaimed dog experts of all kinds offering, uh, you know, many different answers, and speaking to Karen Bruillard in an article for The Washington Post, Heart said that the reason you get all these different answers is that nobody knows for sure why dogs eat poop, and they're basically all just guessing. Fortunately, Heart says that this behavior is gross as it might seem, is not usually dangerous

to the dog's health. But does Heart have an answer about why dogs do it in the first place. Well, not a definitive one, but the authors of the twenty eight team paper do have a hypothesis and it goes something like this, So modern dogs are descended from some ancestral variety of wolf, and wolves don't like poop within their own den. They they like to go out somewhere

away from the den to do their stuff. And this is probably an evolved defensive behavior because the feces of wild wolves often contain the eggs of intestinal parasites like hookworms or pinworms or cosidia, and there there could be genes probably selecting for behaviors that would help prevent your brothers and sisters and other close relatives in the pack

from catching your intestinal parasites. However, maybe sometimes you get a sick wolf, a sick wolf that's in the pack and is not able to leave the den in order to poop. In that case, it would actually make sense to eat poop within the den as quickly as possible, since it usually takes a couple of days for parasite eggs in poop to hatch and become dangerous. So rather than let the poop in the den just sit there for a couple of days and become a potential bio hazard.

There could be a selection pressure favoring an impulse in wolves and their dog descendants to immediately eat fresh poop within the den before it goes over the edge and becomes a risk. And this hypothesis is actually consistent with another thing that researchers have found about dog coprophagia, which was that in dogs who eat who do eat poop, more than eight percent prefer poop that is fresh, no

more than two days old, you know. On the other hand, James Serpel, a professor of veterinary medicine at U PEN, was also quoted in that post piece, and Sir Pell says he finds that the din cleaning hypothesis for coprophagia, that that could be plausible. That might be the case, But Sirple also points out that poop eating dogs tended more often to be rated by their owners as generally

greedy eaters. And that's a quote greedy eaters. So we can't rule out the possibility that the cause is simply dogs with a strong scavenging instinct and some large and indiscriminate appetites looking for a bit of extra nutrition. Well, let's take a quick rake and then when we come back, we will explore coprophagia among elephants. Thank you, thank you. All right, we're back, So Robert, it's time to talk about elephant coprophagia. So obviously, there's nothing cuter than an

elephant calf than a baby elephant. You know. It's just like, if someone shows me a YouTube video of a baby elephant doing pretty much anything, I'm gonna watch it. I don't know, what about a screeching adult possum, Well, that's fun too. I also really like it when skunks stand on their their fore legs and wave their their hinders in the air. I'm pretty much game for any animal video. But there's something about an elephant calf, you know, it's

just so adorable. I think it has something to do with the the large head with the kind of wispy hair, do you know what I'm talking about? The triggers. I think some of the baby schema instinct like that. The part of the idea of the baby scheme as that we are we are triggered with, uh you know, like caregiving instincts when we see a creature with a large forehead and apparently large brain case because it looks kind of like the proportions of a human baby and baby elephants.

They strike me as being kind of like that, right, And then they start eating a little poop, and we're not sure where we're how we're supposed to feel about the whole situation. And this is in the wild, mind you, this is observed in the wild. This is not just a zoo thing or anything. Um, So it leads us

to ask, you know, what purpose could this serf? Well, the poop contains vital bacteria for breaking down plant cellulus, and by consuming some of its mom's dung, an elephant calf essentially gets that microbiome boost towards the consumption of food. So it's it's vital in them making that leap from just just sustaining themselves on their mother's milk to actually

eating as an adult or semi adult elephant. And then they're also going to get some nourishment out of the deal as well as roughly two thirds of an elephant's diet uh ends up coming out the other end undigested. I guess this would be a diet heavy and rough plant matter. Oh, yeah, you know it. So they're they're eating elephants obviously eat a ton they're eating a lot of plant matter, but even their impressive anatomy is only

able to absorb so much of it. By the way, speaking of elephant poop, uh, it's pretty incredible as well due to its a seed distribution. Powers. This was kind of a tangent I happened upon in my research. You know, we often forget this about this when we're considering the ecological impact of elephants and h and also you know some of the ramvoications of their dwindling numbers. But just consider the Asian elephant, which has lost its habitat and

ninety percent of its population over the last century. Um. And these stats come from on the Importance of Elephant Poop by Sarah Zelinsky, published in Science News. She points to a two thousand fifteen ecology publication by a Secca at all uh that points to three plant species in particular that have evolved to benefit from elephant seed distribution, including the so called elephant apple apple, which I was

not familiar with. Um. Most animals can't actually eat the elephant apple because it's just so tough, and as with wild guava, which is another example of this, it's far more likely to germinate if it passes through an elephant rather than say a cow or a buffalo. So key. Key here, of course is the fact that the seed itself has to be undigested in order to actually germinate

and grow new plants. Yeah, and there of course a number of plants that depend on distribution methods like this, like the an animal eats the fruit and then poops the seeds out somewhere, often helping transport the seeds somewhere along the way. Yeah, I feel like this is something this kind of comes back to how humans perceive poop. We we tend to think again with that that sort of worm analogy. On one end of the worm is food, delicious food, and on the other end is just poop,

just utter utter law. It's heaven and hell. You know it's good and evil. But really, you're and most animals would be able to attest to this, have the gift of reason and language that the poop still has a lot of good in it. It's not just this, uh, this transformation from like you know, a hundred zero, it's not heaven in hell. It's more like dinner and leftovers. And you might find, in fact that the leftovers have already been conveniently cut up into pieces for you exactly.

I should also point out that this has been a practice among elephants and elephant can for quite some time. Uh. There was a forty two thousand year old baby female mammoth double lube and she was found to have adult mammoth poop in her digestive system. This seems to be just a part of how you first of all, wean and then also prepare the the the microbiota of the

young elephant calf. Now speaking of similar large mammals with also very cute babies, I was reading just a little bit about the importance in the the freshwater food chain of some rivers of hippo poop. You know, hippo has to do a similar thing. They come up out of the water to eat a whole bunch of you know, rough plant matter, and then they retreat back into the water to just poop it all out, poop it all

out straight into the water. Uh. And this this ends up forming an important nutrition source for fish and other organisms downstream. But of course, too much hippo poop can lead to problems like eutrophication, where there's too many nutrients in the water. I imagined. This is one of one of the many challenges of keeping hippos in an artificial environment is having to clean up water all the time. Oh, I was actually reading something about this. Uh, I wish

I could remember the details. But in regards to uh, Pablo Escobar's hippos, yes, his his hippos which are sweat supposedly still running amok something like that. Yeah. Um, I also remember I've done some hippo poop research in the past. Um, actually a fair amount of, I guess just hippo aanous research, because you've got like a special variety of leech that is only attracted to the hippoanus. They also do that great thing with their tails, the spinning. Yeah, it's the

whirling tail poopy go around. Yeah, it's like a sprinkler system for fresh hippo feces. Well, now that we have that image in your head, let's turn to what I think might be the most impressive variety of coprophagic organisms. This would be the order Lego Morpha, or the Lego morphs. Bunny rabbits, yeah, rabbits, hairs pike has presumably the easter

bunny as well. I don't know, I think I warned people when we mentioned this episode was coming up that they would be treated to an utter ruination of the cuteness of bunnies. But maybe instead, if you're open minded enough, this will even expand your bunny cuteness appreciation and higher dimensions of consciousness. I think I'm more in that that that area. Like when I first started looking into it, I was like, yeah, maybe this is a little gross,

but no, like, no, this is amazing. Like I'm not sure I had any reason to find wonderment in bunnies and rabbits before, you know, accepted if it's some sort of cool predation method by something that eats them. But no, this, this is amazing what we're going to talk about here, and it forces you to rethink not only rabbits, but I think digestion itself. Okay, so what does normal rabbit

feeding look like? What are they eating? What do they do? Oh? Well, you know they're eating carrots the cartoons, if they've taught me correctly, you know they're they're eating plants. They're in a diet with a lot of a lot of greens and uh and you know the gardens of English gardeners when they can get in there though. Funny side fact, I was actually just reading a paper that mentioned some opportunistic carnivory of rabbits, not of rabbits by rabbits. Oh,

that would make sense given everything we've learned about squirrels. Yeah, I think this was an isolated case. It's not like this is super common, but it had at least been observed. Well, they've also been observed plenty of times engaging in coprophagia, and it's actually a clever way by which they overcome some of the shortcomings of their digestive systems. So their

hind gut fermenters, and what does that mean. What means that the bacterial fermentation that breaks down much of the plant matter they consume, it takes place in the hind gut. In rabbits, this is in the secum and and so yeah, you're having all of this, like vital breakdown of the material taking place rather late in the process. And yet most of the nutrient absorption takes place in the stomach and the small intestines, which is of course earlier in

the process. So you have this weird situation where there's so much of the nutrients that they need are not really coming online until it's basically poop ready for depositings. So it's kind of like one of those movies where the plot doesn't make sense until everything comes together right at the end. Kind of you kind of need to see it again after you've seen it to put everything

together exactly. It's also worth noting that we're dealing with creatures that are small, gutted and uh and have very high metabolisms, which also plays into the scenario. So what's the what's the rabbit to do? Why you simply run it all through again you watch the movie again. Uh and but but it's more elegant than that. It's it's more amazing than simply okay, well they're they're poops, still have a lot of nutrients, so they eat their poop again. They have two types of poop WHOA, so they have

poop toggling. Essentially, they produce what is called a sika trope or night feces or night poops, if you will. While normal daytime feces is brown and hard, the night poops are dark, soft and coated in mucus, and these they eat up right away. Generally, this has taking place, I understand, like basically the early more the early hours of the morning, uh hand, or you know, the the

very latest portion of the night. However you want to slice it, thus night poops, and they eats up up so swiftly that I'm to understand that many pet owners don't even know what's happening. Uh, And in doing this they absorb those vital nutrients on the second pass. In fact, if a rabbit doesn't eat its night nightpoops, that means there's something wrong with it. So according to help Doc,

my rabbit is not engaging in coprophagia exactly. I mean, that's basically the reversal we see, the reversal of human expectations for coprophasia. According to the Cornell veterinarian paper Coprophasia and Animals, a review by Slave and Brand, the night poops are quote swallowed like pills, and in the case of the pika for instance, uh, the night poops are essentially a mix of partially digested moss and gut bacteria. And it's actually six times more nutritious than the moss itself.

So it's almost like cooking increases the nutritional profile of food. Well, we've talked about it fro from the human perspective, cooking is the externalization of digestion. It's technological digestion. Yeah, so yeah, this is this is cooking via the pike a gut. They also point out that young rabbits begin eating their mother's night poops before moving onto the consumption of their own. So again we see this kind of weaning process similar

to what we saw in elephants. And uh. This also supply supplies nitrogen, protein, sulfur, and vitamins, and up to on consumption of night poop may be necessary for these creatures to intake adequate levels um um of these substances. Okay, so now that we have expanded your mind about cute bunnies, I assume it will be less of a leap for

people to find out that rats consume feces. Right. Oh yeah, I feel like this should be a no brainer, like it really, I think people are going to be surprised that they don't eat as much poop as as rabbits do. But a single rat consumes a varying amount of its own dung. We're talking between five and fifty percent of

its own fecal output. And as with rabbits, we see some key nutrients in here made absorbable via that first round of digestion, and it's a way for them to hit target absorption levels prevent them from eating their own poop. And young rats experience a depression and growth rate of about fifteen and it's especially useful as a way for them to make up for shortfalls in their natural dietary nutrients.

So whereas human adults tell human children like don't drink coffee, that will stunt your growth, your adult rats would tell their their rat pups, don't not eat your poop, that will stunt your growth. Exactly. It's also been observed to boost the rats and microbiotic performance. And in fact, thiamine is produced in the rats intestinal tract and is not absorbed. They have to eat it then to pick it up.

So if rats are are permitted from eating their own feces, such as with a laboratory via laboratory tail cup, you'll have to add vitamin K to their diets to make up for it. And similarly, they require B complex if not allowed to ingest their own feces. And with rats, just as we saw with with with rabbits, it begins with the young eating the mother's feces with the pheromonal

encouragement of the practice. Maternal rat feces contains high levels of the oxycolic acid that's lacking and pre weened weaning rats, and this is a steroid that promotes immune development in the intestinal tract. So part of what you're saying is that when you find rat poop in the back of a kitchen cabinet or something, there actually probably was originally more rat poop there and they just they took some

of it along with them. I'm not sure on that, you know, I'm not sure when they're I don't think it was really reflected in this main uh Suave and Brand paper, like when they're eating the poop, if this is only occurring like mostly close to home, or if it's going to occur in your cabinet potentially. Now, another animal that is famous for wallowing in its own filth, of course, is yield poor sign that's right, uh, the pig. And this is another animal where people would be like, yeah,

that that that makes sense. A pick would probably eat its own poop. Um adult pig poop is rich in iron, and piglets will, according to Suave and Brand, consume about twenty grams of maternal feces per day, and this plays a role in preventing iron deficiency anemia in the piglets. Now beyond the realm of pigs, it's also been seen in non human primates, with B twelve and fatty acids coming into play for some monkeys, but it does not serve as a major source of nutrients in non human primates.

Will come back to non human primates in a bit. In horses, however, between the second and fifth week after birth, a full will apparently eat part of the mother's feces, and it also occurs in mature horses that have low protein diets. I'd like to just read a quote from that Suave and Brand paper. Actually they say quote. Coprophagia is essential for some species of animals, providing nutrients which

contribute to growth, development, and maturation of the animals. The practice must be considered in the interpretation of comparative investigations done with coprophagous and non cooperate agus animals. The impact of coprophasia in laboratory studies using rodents and rabbits could seriously influence test results, especially in the fields of nutrition, microbiology, pharmacology, and toxicology. So what they're saying is science needs to

take way more poop eating into account. Basically, Yeah, and this is something I still reflected in some other papers I looked at where they said, there's just there hasn't been enough research on some species and they're they're poop eating. I mean, certainly rabbits have received a lot of attention, but but this is a this is an interesting point about especially UH lab mice and rats that we're studying

to understand so many things about about human physiology. Now while we're on the subject of animals that are probably less surprising to find out that they that they engage in some poop eating. Obviously, insects and invertebrates of various kinds are going to figure big into this kind of picture.

In fact, I remember I had a biology teacher ones who was talking about his expeditions to the jungles of South America, and he talked about how you know, in the morning, if you if you were out in the rainforest, and you would you would venture out away from the

camp to release a large bowel movement. After the coffee hour, UH, you could basically sit there and watch it become a chemical beacon for invertebrate forest life, where we're slowly thinking all these insects and different kinds of species would just descend on it from all around. And uh, that image is stuck with me ever since I would kind of like to see that. Yeah, it's far It's a far different scenario in our urban environment, where if you go out and poop on the sidewalk in the morning, you

may attract attention. But but but may I don't know. I'm joking, But I mean it's not like we don't have a lot of insect life in the city. Yeah, I guess we do. Yeah, I mean you will certainly see flies on poop. I mean it's a cliche for a reason. Now. One of the most impressie consumers of of poop in the insect world is, of course, the dung beetle. These are amazing animals they are and um, and yeah, I think we tend to be cool with

the dung beetle. I mean, the dung beetle is kind of funny because of what it's doing, especially if you're watching a variety of dung beetle that rolls the poop away. How come dung beetles don't seem as gross to us as the flies and maggots that land on poop. I think part of it is that they're generally we're generally when we're watching videos of it, we're watching dung beetles that are rolling away like animal poop, and yeah, animal poop,

and specifically herbivore poop, which tends to be far nicer poop. Like, really, if you have to, if I had to deal with a bunch of poop, like just to scoop it, you know, give me, give me horsepoop the day of the week, it looks more like mud with some hay in it, right, And basically it is. I mean, just think back to the elephant poop example and all the all the stuff that is still in there unabsorbed. But we have a lot of different types of dung beetles. I've seen the number.

I've seen it as low as five thousand, but I've also seen it sited is like eight thousand different species of dung beetles, and they can be found on every continent except Antarctica. They thrive in numerous environments as well,

not just grasslands. So I feel like sometimes we have a false idea of dung beetles just based on seeing like one or two segments in a nature documentary, and they given their name implies they subsist almost exclusively on the extrement of other organisms, although they can sometimes feast on carrion leaf, litter, mushrooms, and decaying fruit. Some of the species famously roll balls of dung away from the pile. Everybody's seen this, like the the image of them pushing

it like a boulder, like somebody in tartar Us. You know, Oh yeah, because that's one of the things they make. They make a bee line, they make a straight line, and they use some incredible strength and also some some fairly incredible navigation U techniques to to really pull this off, because they have to be fast. A dung, as we've discussed, loses its nutritional punch rather quickly. Uh So it has

to the ones that actually roll it away. They have to roll it away in a straight line, get it somewhere where they can deal with it, and they might have to deal with competing dung beetles on the way. Now you might not know the answer to this, but why is it that dung loses its nutritional value over time? Is it? Uh? Is it the microbes in it that are consuming a lot of the nutrients. I think that

is the case. Yeah, I mean, and it's almost like the dung is alive and dying, you know, and it has to be uh, it has to be dealt with whether quickly. Um. Now, I mentioned that you know varieties that roll, they're dung. While rollers are certainly the most famous, there are also tunnelers, so they tunneled down into the poop. And then there are dwellers that dwell atop the poop. Um.

So these are the things that the mountain. Yeah, basically there's king of the mountain, there's king under the mountain, and then there's he who rolls poop away from the mountain. Uh. And those are the three categories the at of poop. Now, according to Believe it's Dr John M. Capinera. A one point five kilogram or three point three pound load of elephant dung was observed to attract sixteen thousand dung beetles who eight buried and rolled it away in less than

two hours. Less than two hours. That's that's incredible, and that's that's difficult to imagine. But you know, if you have an entire swarm of dung beetles. I almost don't believe that two hours all by insects. Well, well, maybe we'll check that in qua and make sure that holds true. No, I'm sure I believe it. I believe it all right. Well, according to the San Diego Zoo, the average domestic cow drops dung like ten to twelve times per day, and each pat of poop can produce up to three thousand

flies within two weeks. In some parts of Texas, dune beetles bury about eighty percent of cattle dunge. So just imagine what life would be like without dung beetles around to to con whom the poop Robert, That sounds like a messy planet it would be. But thank thank God for the dung beetles. All right, let's take a quick break and when we come back, we will discuss picture plants than alright, we're back this time with a non

animal feces consumer. Well, it's much less surprising, I guess, than animals eating poop to hear of plants benefiting from poop, because obviously, you know, you could think about fertilizer and stuff like that. They're there are nutrients in poop that can sink into the soil and nourish the roots of a tree or something like that. But I want to talk about a more direct kind of fecal gobbling by plants, and that would be, of course, the case of picture plants.

Now we've discussed picture plants on the show before. These are generally carnivorous plants with these picture cup shaped leaves that form a pit trap. And the general predation strategy

of these carnivorous plants goes like this. So you have a delicious smelling chemical lure, some kind of actor or something to attract insects to your picture, and then the insects land and try to feed, or at least try to investigate, but the edges of the picture slippery, and then the insect falls into a pool of liquid down inside the cupped leaf. Now, once in the liquid, the insect dies, and then the body is digested by enzymes down in the pit, and the plant of course feeds. Now.

This is often especially important because the picture plant needs those arthur pod bodies is a source of nitrogen, which is a crucial nutrient for them, and which is often scarce in the kinds of soil where the picture plants tend to grow, which can be like swampy soil or like heath soil, just not very nitrogen rich. But a curious thing has happened to some picture plants. Some seem

to have evolved a taste for poop. And now I was reading a great piece in National Geographic by Ed Young, one of our favorite science writers, about the picture plant Nepenthes hymnslayan a. And so there were some researchers that Ed was talking about. One was Omar Graph from the University of Brunei, Jerusalem, and he noticed something odd about

this species of plant to pen these Hymns layana. It was sort of low on fluid compared to other picture plants, and it also didn't release obvious chemical attractants for insects, and it tended to have about seven times fewer insects than the pictures of other species. Now, instead of insects in the pictures, there were often bats. There were a type of bat known as Hardwick's wooly bat or Cravoula hardwicki, roosting,

sometimes roosting as families inside the plants. And so Graph work together with Caroline and Michael Schooner from the University of Greifswald to investigate the apparent mutualism between bats and picture plants. Obviously there's some kind of relationship going on here. What is it. You've got big pictures that bats can fit inside, very little fluid, very few insects. But of course the pictures were full of you guess it, poop bat feces, also known as guano, which is incidentally a

great source of nitrogen. Now, the researchers found that the plants were getting so much nitrogen from the guano that they didn't need to kill nearly as many insects. So here's the question, how did the pictures attract the bats? Because bats navigate mostly by echolocation, they determined shapes in their surroundings by making sounds and then listening for those sounds to bounce back off the objects in the environment,

forming a three D sonic map. And there are similar shaped other species of picture plants in the forest, and there's just a lot of stuff in the forest to sort of like muck up your view. So how did the himsleana plants attract the bats? The researchers mentioned before teamed up with Ralph Simon of the University of Erlangen, Nuremberg, who helped out by bringing along a robotic bath head

and so ed Wrights quote. The team found that the back wall of in salayan a, the bit that connects its lid to its main chamber, is unusually wide, elongated, and curved. It's like a parabolic dish. It strongly reflects incoming ultrasound in the direction it came from and over a large area. Other picture plants that live in the same habitat don't have this structure. Instead, their back walls

reflect incoming calls off to the sides. So as the wooly bats pepper the forest with high pitched squeaks, the echoes from in Him's leana should stand out like a beacon. So the researchers also tested this apparent function by modifying some of the plants sort of hidden among shrubbery in a tin full of bats to see if it would change the rate at which the bats were attracted to

the plants, and it did. In a paper published in Current Biology, UH, the authors found that if you took one of these plants and you sort of amputated its reflective surfaces, the bats couldn't find it as quickly and ed writes quote and when given a choe as they

mostly entered pictures with natural, unaltered reflectors. So here's a case where the plant has evolved to instead of specializing in capturing, trapping, and eating insects, it specializes in providing a good home for bats to poop in it, and even changing its own shape over the generations to become a better attractor of bats because it reflects the sounds they make better. Now, this is not the only picture plant that has come to specialize in receiving poop as

a as a main part of its diet. There's another picture plant called a Nepenthes lowy that does something similar by functioning as a kind of delicious toilet for tree shrews in borneo u. The young versions of this plant tend to trap ants and other insects like a normal picture plant would, but the more mature plants, which grow up higher in the air on vines and other plants, they attract tree shrews with sweet nectar, and while the shrews are perched on the plant licking the nectar, the

shrews poop inside the plant, providing crucial nitrogen to the plant and In fact, the mature aerial plants really don't trap many insects at all. They just want poop, that's all. It's just tree shrew come and poop in me. And they've evolved to specialize in this. While most carnivorous picture plants have these slippery rims I mentioned, right, you know, they want a slippery side on the pictures, so the insects fall in, the mature uh plants of the low

E species don't have a slippery rim. Instead, they've got a rim that the tree shrew can stand on safely and poop comfortably. After all, like you wouldn't design a human toilet with like a lubricated seat, right, you know, you don't want people slipping around. So I also found another more recent study by the same authors of that study ed Young road about and isn't at gop s, but with some other authors in a Journal of Ecology

in two seventeen, called ecological outsourcing. A picture plant benefits from transferring predigestion of prey to a bat mutualist uh So they point out here that you know, mutualism is a type of symbiosis between two species in which both species gain a net benefit from the interaction. UH classic examples would be like animals in their gut flora. The gut flora gets something out of it, you get something

out of it. But also like flowering plants and pollinating insects, where the insect might get nectar and the plant might get reproductive material spread around, you both get a net positive. And so the authors point out that lots of ecologists believe that a lot of times mutualism seems to evolve when a service that an organism originally had to perform for itself could be done better by another species. And

the authors refer to this as quote ecological outsourcing. So an example would be a plant that used to have some, you know, very ineffective way of spreading pollen around, but then insects began spreading the pollen in a much more efficient and targeted way. But of course, how would you test that it evolved this way. Well, the authors came up with a way to test this using that relationship I mentioned earlier between the picture plant nipenhees hims lana

and Hardwick's wooly bat, the care Caravoula hardwicki. And so the picture plant houses the bat like we said, the bat poops inside the plant gets necessary nitrogen, and the authors write about their method quote, we measured the benefits of ecological outsourcing by comparing survival growth, photosynthesis, and nutrient content of in Him's Leona plants fed with bat feces

to those fed with arthropods. To investigate the costs of such outsourcing processes, we repeated the experiment with the closest relative, Nepenthees rafless Cianna that is not adapted to digest bat feces. So the authors found that Him's Leyana plants fed on a diet of poop had better survival growth and photosynthesis than plants of the same species that were given only insects instead. Quote. On average, plants covered nine of their

nitrogen demand from feces under strong nutrient deprivation. But what about those non poop adapted species of plant that got to try out a poop diet in this experiment The author's right quote, Despite raf. Lysiana's higher arthropod capture rate, feces covered a large part of this species nutrient demand as well, suggesting low costs for outsourcing. And then, finally, the author's right quote, outsourcing pre capture and digestion to the mutualism partner seems to be a beneficial strategy for

in Him's leana. It may explain the evolutionary trend of several carnivorous plants to lose their carnivorous traits while increasing their attractiveness to mutualistic partners. On a much broader scale, we propose that ecological outsourcing could be one of the major drivers for the evolution and maintenance of mutualisms. So, in other words, you can think of the bats as providing a kind of predigestion service for the picture plant. The bat eats the nitrogen rich food source, breaks it down,

then releases it into the plant's mouth. It makes sense, right, Why eat the insects directly when you can eat this byproduct of the insects at the bad eats. Yeah, And it also makes me think about you know, when we've talked about the possible origins of predations in the Cambrian period, like if organisms we don't know that this happened, but just if it's possible that predation began when scavenging or organisms eating sort of like dead other animal matter just

sort of transitioned to live animals. Uh, this could be a sort of like backward transition of that kind, right, yeah, I think so, And and again it also forces us to rethink what is going on in digestion, what is going on in the transformation from food to poop? Totally all right, So I want to come back to humans again. So at this point, yeah, if you don't want to hear about human coveraphagia, um, maybe you want to check

out for this episode. But hopefully at this point we've demystified it a bit, uh, and you're ready to hear a little bit about humans and also some of our our our ape relatives. So of course, human a prophagia has long been the subject of various curses, insults, and

of course art. I think we can all think to to various um works of literature or cinema that the drag out coprophagia is, especially as I've seen it popular in like nineteen seventies cinema, especially avant garde stuff where they want to I guess say something like really like stark and disturbing about the nature of human existence. Yes, the spirit of the Marquis assad Yeah, yeah, there's a

lot of of of of poop eating in that for sure. Um. But really, I mean any amount of poop eating tends to stand out in the work and and and you run the risk of it overshadowing everything else that you're attempting to do. A couple of cinematic high points low points, uh that come to mind in this area. There's, of course, uh, the scene in John Waters Pink Flamingos in which the

actor Divine eats dog feces. And I later heard an interview from him talking with the Fresh Air Terry Gross about and talked about like calling the doctor afterwards and claiming that a child had eaten dog feces and he wanted to see, if, you know, if the child was going to get sick, and the doctor was like reassuring

him that it would, you know, would probably be okay. Um. Another great scene, of course is the scene in Caddy Shack where Bill Murray's character retrieves the suspected feces which is actually a candy bar from the bottom of the pool and uh and and holds it up, sniffs it and invites into it. But anyway, the point here is that for humans is largely something that's relegated to the room of madness, perversion, and horror. It's also been done as an act of protest, and indeed it's it's considered

an extraordinary disorder of human behavior when it occurs. We're not like those animals that sometimes eat poop for nutritional deficiency reasons. Right, our closest ape relatives don't benefit from the act as other animals do. Chimps have been observed to do it in laboratory conditions, probably due to dietary

deficiencies or captivity induced behavioral problem. Now, as for guerrillas, I was reading a bit about this in the primate conservation paper UH Coprophasia and Intestinal Parasites Implications to human habituated mountain guerrillas. This is by Grassic and Cranfield from two thousand three, and they wrote that coprophasia is commonly

observed in mountain guerrillas. Adults sometimes eat their own feces following defecation, or the old feces of other guerrillas, which is interesting they didn't I don't think they really went into all this and do this all that much. But it comes back to the whole freshness thing. I wonder, why eat the old poop? But Anyway, infants sometimes eat feces of other guerrillas or other animals, and it's considered normal, and it's been argued that the gut flora explanation is

likely valid here. It's thought that their herbivore diet likely benefits from some level of symbian seating. However, with this sort of practice comes the possibility of parasites, and indeed, a survey identified forty one species of indo parasites from cat to been wild guerillas, twenty nine of which can

be transmitted by coprophagia. However, they also stressed that coprophagia has been quote generally neglected in medical parasitology, except in mentally retarded people with behavioral apparitions such as coprophagia or co prophilia, requiring institutionalization. Again, we're clearly a non coprophagias species. It isn't a normal part of our behavior, so it's

not something we're evolved to do with much proficiency. I was also reading an International Journal of Psychological and Brain Sciences article titled Coprophilia feces lust in the forms of coprophagia, coprio spheres, scatolia and plastering and dementia patients are Thoughts and Experience, which is a good paper, but certainly, um, it doesn't sound like a fund read. It's not exactly a fun read, but it's it was insightful. It's it's not the first thing you want to read during your

coprophagia research. But they pointed out that in primates that the consumption of feast these may serve quote as a behavioral adaptation that provides animals access to energy and nutrients and maybe an important nutritional source for older and ordentally impaired individuals during the dry season. Dentically impaired meaning they just don't have the teeth to handle certain foods. Oh

I didn't even think about that. The idea that, uh, for some animals species could be just an easier food source, and it's something to fall back on when you can't maybe chew up the normal kind of stuff you would be eating. It is predigested, like you said, uh, And then they suggest the following quote, Dimentia patients have a diminished mental capacity that constantly is being reduced towards a

capacity analog to a newborn's possibly acquiring all primordial instincts. Furthermore, as nutritional decrease in the amount eaten, which is all egophagia. That the eating of only a few foods uh together with the loss of weight, is probably the most common disturbance in dementia UH, something that could lead in a search for supplementary food sources. So they point out that.

They also point out the dementia can also result in the hyper sexuality and sexually just uh inhibited behaviors, which could also entail the sort of activity they're also known to make and throw copra spheres in the manner of other primates, which is also curious. So poop balls balls right, Um. They reject the idea though that is linked directly to

dietary deficiency. But I feel like this this is putting like a weird and interesting spin on it, like the idea that it is in dementia patients, which seems to be the the the only area where it really occurs. That it is kind of this primordial return to some like very base h like primate activities. Well that somehow you may be a result of like instincts that are activated but normally inhibited. Yeah yeah, so but again they they say that this is an area that really needs

needs more research. Um, they said, there's actually there's not a lot of hope for dimentia patients exhibiting this sort of behavior, and that more study is needed, but of course also more empathy. There's apparently a tendency in institutional environments to provide less care to such individuals, and if there's hope to be had, they say, it's through empathy and interventions of psychological and pharmacological nature. Yeah, I can

certainly see how that could be the case. Like it's an unfortunate case where like a very gross symptom makes it actually harder for a person to get the care they need, just because like the people who would be providing the care find it repulsive or something. Yeah. Yeah, and then you know, because they're also gonna be they're

gonna be dirtier because of this activity. It just and it, and then you end up invoking all these human taboos, which even in a clinical environment with trained professionals like in in the best of conditions, that can see where it would definitely be Uh, you could definitely prove a challenge. Now to close out with something a little more fun. From that paper, Um, they did point out that quote in ancient Greece. During the orgies dedicated to the god Dionysus,

bizarre erotic fetishes were in constant use. Many depictions of people defecating in clay pots during an orgy proved the narcissistic erotic deviation in ancient cultures. It sounds almost judgmental, right, But they included some images of this, uh in the in the paper. That paper had had a lot of images, a lot of a lot of photos. Um. But again,

I feel like human coprophagia uh. Though certain certainly um a tricky subject, even it makes a lot more sense having looked at how it works within the normal behaviors of many animals. Yeah, I agree. Now I have a question, actually, yes, is dung vegetarian? Well, a lot of the dung we've talked about is is herbivore dung? Yeah, that be a follow up question. I guess, does it matter whether the dung is the dung of a carnivore of or of a herbivore it is an animal product in a way? Well,

I did not. I guess maybe the question would be as dung vegan? Well, I feel like I don't feel like we really discussed any carnivores in this episode. I mean, everything was at least an omnivore, if not a nerbivore. Um. Yeah, I didn't come across any research involving carprophagia among carnivores, so yeah, I'm not sure. Um, I didn't see any articles about cats or big cats or pack hunters, So I don't know. That's a that's a that's an interesting

question to leave out on. I'm not saying we're gonna come back for Coprophagia Part two, but uh, but it is worth worth looking at. Well, here's a question start with on part two. Is dung paleo? I don't know. In some respects, maybe it is that that maybe so maybe so all right, so there we have it. We're gonna go and close it out here. Obviously a lot

of people are gonna have some comments on this. UM. Probably related to your pet rabbits, your pet dogs, maybe farm animals, pet gorilla, pet gorilla's Uh, maybe you you professionally have some sort of inside here. Maybe you've worked with THEMNIA patients, you know, I've uh, we're we're up for any kind of insight into this topic that you, the listener may have to share with us. In the meantime, head on over to stuff to Blow your Mind dot com.

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