Do they sweat blood? Will one kill you? What are cocaine hippos? Is Moo Deng… okay? Actual real life Hippopotomologist Dr. Rebecca Lewison explains how hippos have some of the best – and worst – PR. We chat about pet hippos, subspecies, daily diets, the current state of hippo conservation, the absolute chaotic affection we have for pygmy hippos, their role as ecosystem engineers, what’s up with their nostrils, and how to keep a hippo in your pocket. Also: how to flatter your friends into planning a group vacation. Visit the Lewison Lab at SDSU and follow Dr. Lewison on Google ScholarA donation went to The Wechiau Community Hippo Sanctuary (WCHS)More episode sources and linksSmologies (short, classroom-safe) episodesOther episodes you may enjoy: Pinnipedology (SEALS & WALRUSES), Wildlife Ecology (FIELDWORK), Cucurbitology (PUMPKINS), Culicidology (MOSQUITOES), Scatology (POOP), Conservation Technology (EARTH SAVING)Sponsors of OlogiesTranscripts and bleeped episodesBecome a patron of Ologies for as little as a buck a monthOlogiesMerch.com has hats, shirts, hoodies, totes!Follow Ologies on Instagram and BlueskyFollow Alie Ward on Instagram and TikTokEditing by Mercedes Maitland of Maitland Audio Productions and Jake ChaffeeManaging Director: Susan HaleScheduling Producer: Noel DilworthTranscripts by Aveline Malek Website by Kelly R. DwyerTheme song by Nick Thorburn
Oh, hey, it's the fish soup that you spilled all over the kitchen, which actually did happen to me, Hallie Ward. And this is Ologies. It's a podcast where we explore an ology a week. So you are tuning into a chat about hippos. It will leave you changed. It changed me.
We've got a true hippopotamologist, a professor of biology at San Diego State University, whose research at Vassar and UC Davis focused on vulnerable wildlife populations and conservation and, of course... Hippos. So they know way more about hippos than most people ever will on the planet. And they're in a very elite club of hippopotamologists.
And I asked her all of my very not smart questions as well as yours. If you want to submit a question ahead of time before we record... You can become a patron at patreon.com slash ologies. It costs about 25 cents an episode to join. It helps fund the show.
You can also buy ologies merch at ologiesmerch.com or you can support for no dollars by leaving us a review, which helps convince me that I'm not broadcasting to an assortment of dolls in a basement. And I read all your reviews, such as this one from Chris F., who writes, Hippos, hippos. You might know, you probably know that hippopotamus in Latin, it means river horse.
If you didn't know that, I'm going to give you a second. It's hippo means horse, potamus means of the river, hippopotamus, river horse, these beasts. They are artidactyls, meaning that they have an even number of toes, like a bison or a deer and a giraffe. Those are all in artidactyls.
And after elephants and rhinos, hippos are the largest land mammal, even though the common hippo's scientific name is hippopotamus amphibius. Terrestrial animal? We'll get into it.
So point your weird little ears our way to learn about knife teeth, blood sweat, swamp hippos, pet hippos, subspecies, their daily diet, the current state of hippo conservation, the absolute chaotic affection we have for Mudang. How many people hippos kill a year for real? If you need to apologize to a hippo. Who are hippos' best friends? Their role as ecosystem engineers.
If you have ever been brainwashed about a hippo, what's up with their nostrils? How to keep a hippo in your pocket? And tips on flattering your friends into planning a group vacation. With conservation biologist, professor, and actual real-life hippopotamologist, Dr. Rebecca Lewison.
Rebecca Lewis in She, Her.
Thank you so much for doing this. As someone who studies hippos, this is a busy time of life for you, and we will get to why. How long have hippos been part of your bread and butter?
I started studying hippos as a graduate student. I was at UC Davis doing my PhD in ecology, and I kind of stumbled into this project to work on hippos. My interest in was to study behavioral ecology. At the time, I just really loved, it was fascinated by sort of the minutia of animal behavior. And I thought, oh, this will be perfect.
I'll study hippos, which anyone who actually studies behavior will be laughing when they hear this because you think like, no, no, no, no. You study behavior on small things like birds or squirrels, not hippos.
Not her. She dedicated her research to a notoriously challenging terrestrial species. What the hell happened?
But I had this opportunity because I had spent time in Kenya as an undergrad and so could speak some Swahili and had traveled around and just had a fair amount of field experience. And so I got this amazing opportunity and kind of just fell into it and didn't realize what I was getting into at the time and sort of entering this amazing world of this understudied animal.
So it might be easier to see the behavior of spiders if they're living in the lab and stuff. Exactly.
You can't study it in the lab. You can't manipulate it at all. They're actually really hard to study, period, because they spend almost all their time in the water. You couldn't pick something less studyable if you tried.
You know, pop culturally, there's no lack of hippos.
Who didn't play Hungry, Hungry Hippo as a kid?
I played it all the time. They don't even eat marbles in real life, right? They definitely don't.
What are they eating? Are they eating mostly plants? They are eating mostly plants. So they are herbivores. They eat grass. So we can be a little bit more specific than that. They're basically like lawnmowers. They eat a tremendous amount of grass and it has to be pretty short grass. Why? Well, because it's just wait till we unpack this.
Like hippos are amazing head to tail, but they don't really have a neck. They don't really have any structures in the back of that part of their spine. So they can't really lift their heads up like when you think of like giraffes or elephants. They can't do that. So they're really limited by the grass height.
No neck. Hippos are neckless. And so are they foraging the grasses on the banks of rivers or are they coming up on land?
Yes, that's a great question. And it's a little bit of a yes. They do forage on the banks. But what you'll see if you're in a place where there are a lot of hippos is you really know a lot about where hippos are going because they have these trails. And you can look down on the trail and see like a hippo print, another hippo print. So they just follow these trails for a really long time.
So they're really well established to what we call grazing lawns. So areas of short grass that are some distance away from usually the water where they're in.
So they have stomped down a little highway that leads to a food court of short grass. It's like a free buffet, but it only serves short grass. If hippos are like the size of a car, a small car, and they're eating just a very particular kind of grass down a long trail, how are they getting enough calories to have so much cake, to have such dump trucks?
Yeah, it's crazy. We think they eat somewhere between like maybe 50 to 100 pounds. We don't 100% know because it's hard to tell. And obviously in captivity, their diet is much better. You'll see them like eating watermelon or pumpkins, you know, if you've seen the videos. So they're not necessarily super particular on the species of grass, just the height of the grass.
So I think these grazing lawns are there because of them. And they continue to get mowed down by hippos. And they're pretty long lived. So I'm sure they have a lot of information that they store. And if you want to study, like if you were a graduate student and you were captivated by foraging behavior, that's what you do. You'd follow the paths. You'd sit in a vehicle and you'd get some...
crude night scope and you'd watch them for hours and hours and hours. And that's basically what I did. Are they nocturnal? Yes. They only come out of the water at night. What? And we think that's because of thermoregulation, right? They're adapted to be in the water. They don't do well if there isn't standing water and they'll die without that. So in the dry season.
And so for most of the year, they are only coming out of the water at you know, when it's dusk and getting dark. So yeah, what I would do is sit, I would drive my Land Rover to the place where that foraging lawn was and then I would sit on the roof with a pretty old school night scope and watch them forage. That was, that's what I did for about a year.
When would you sleep? Would you sleep during the day?
I have some crazy stories of falling asleep and like waking up to elephants at my eye level because I would fall asleep. Like you said, I wasn't getting enough sleep. But yes, I would sleep during the day and try to stay up. And I would have to do it when there was some full moon because it was really crude. It was, you know, mid 90s. So we had night scopes, but nothing like we do now.
What happens if you're asleep on top of a Land Rover watching hippos and an elephant wakes you up? That's a good question.
The incredible thing is what I remember doing is picking my head up and I'm literally at eye level because I was on the top of this pickup truck and I literally just picked my head up. I saw an elephant and I was so tired. I just put my head down and went back to sleep. No. Yeah.
Did you think you were dreaming for one second?
I think I woke up in the morning and I definitely was like, What? But, you know, for people who work in the field and yeah, obviously I was careful and, you know, followed all the protocols I was supposed to follow, but amazing things happen.
Just a normal day on the job for a hippo ecologist. So you're absolutely in a safari park of life or you're surrounded by something that sounds like a fever dream. What are you doing when you're watching them at night? Are you taking notes like this one went and did a poop on this one or this one seems to be crying? I know.
So I'm going to say it out loud and then people are going to think like, what scientists do, what? But I was actually counting the number of bites and steps. I know, I say it out loud and I just think, what? And it does sound like minutiae to me too, but it's fascinating. Like we know what we do. What do hippos do? How far do they go? Can they just go anywhere?
Like you were asking those questions initially. So I spent all this time trying to understand sort of their strategy. How do they make it work? How do they get enough? How do they decide where to go? And how do you make choices about where to forage?
And so when we see hippos in zoos, they are opening their gaping maws and a whole pumpkin goes in. But do they have that kind of experience ever in the wild?
They don't. Hippos in captivity, all the accredited places that hippos are living, takes amazing care of the animals. They give them lettuce and pumpkins and watermelon and amazing things and very, very well fed. But no, nothing like that happens to hippos in the wild.
How long do they live? You said they live a long time?
Yeah, we think they live around 30 to 40 years in the wild. And in captivity, they can live quite a bit longer.
Okay. They're horses of the river, right? Like water horses? Yes. How are they extracting calories from a bunch of grass? Do they have stomachs like hippos? I mean, stomachs like horses?
Oh, thank you.
Okay, so memory said they are incredible head to toe. So they have incredible stomachs. So anyone who's like fascinated by stomachs, there's not going to be a very large slice of listeners, but
You out there?
They have all this interesting stomach structures that actually is similar to what cows have. They are not ruminants, but they do have this like blind sack. They have like this three chambered stomach, but they do something similar to ruminants. So they don't have like cud, but they keep things in their stomach a really long time.
And I think that gets to your question, like way more than elephants are like conveyor belts. It goes in and it goes out. And if you see an elephant poop, I don't know who has, but you'll notice like, oh, I know what that is. It looks just like what they just took in. But for hippos, not so. So it really breaks down a lot so that this three-chambered stomach has this ability to extract resources.
So even though 50 to 100 pounds sounds a lot for wild hippos, like you said, they're size of a VW bus. And so they're using this three-chambered stomach structure to extract all the nutrients and keep things in their stomach kind of a long time.
So if you're a hippo doing your thing, it's say a Thursday and you're eating an average of 75 pounds of mowed grass, which is about two huge garbage bags full of lawn clippings per day. So much salad. Your favorite dressing, I guess, is mud. There's no croutons. Maybe you got some accidental worms in there, but you're eating dirt grass. It's the breakfast of champions. It's the lunch of champions.
It's the dinner of champions. How many pounds are we talking of hippo?
So they're about like 2,500 to 3,000 pounds. In the wild.
In the wild. And then pygmy hippos, by contrast. Pygmy hippos, by contrast, are about 400 to... So there are only two species of hippopotamuses or hippopotami. Either word is legit and fine. I thought there were maybe 10 species of hippopotamus, but there are two. The common big-ass hippo that you're used to is a hippopotamus amphibius, and then there's the pygmy hippo, Coeropsis liberiensis.
You don't need to know those names, but there's just two species. And pygmy hippos are one-sixth the size of a regular hippo or a common hippo.
Really, really quite a bit smaller. Yeah.
That's kind of like a pig, right? A big pig.
Absolutely.
Wait, how come I didn't know about pygmy hippos until now?
This is the reason most people don't. It's because pygmy hippos are only in West African countries. And even within West African countries, they're only in four of them. And they're very, very secretive.
Whereas the big hippos that you're used to are just like here. They're like, I'm in the river. What's up?
So we think of common hippos right there, this iconic animal of the African savanna, right? You'll see a picture of like a big hippo gaping with a sunset behind it. Until 2006, we hadn't even ever had a picture of pygmy hippos in the wild.
No.
And it's because they're very rare, right? They're an endangered animal. And there used to be a very large forest complex there. in Sierra Leone and Liberia and Guinea and Cote d'Ivoire that kind of went over that entire region. It's largely been lost or there's been a lot of habitat loss of that forest. And that's what pygmy hippos rely on. They're also solitary.
So they don't do this big group aggregation that we see with common hippos. So it's not surprising. They're secretive and solitary cryptic forest animals. And there's very, very few of them.
These little big babies, they live in Northwest Africa in forests. They keep to themselves. They come out at night like Mothman, and they're little. They're like farmhog size. As for how long humans have been, like, gazing at them from behind a fence, according to this 1972 paper, The Care and Breeding of the Pygmy Hippopotamus in Captivity says,
The first time they were introduced into captivity was in 1873 in a Dublin zoo. And I was looking to try to find out more about that. But instead, I stumbled upon an article about a Scottish zoo who just a few months ago welcomed the birth of a baby girl pygmy hippo. And then they made the decision to name her Haggis. In all fairness, she does resemble kind of a gray lump made of skin.
But they didn't have to go there. But yeah, the people, they want the baby pygmy hippos. With little sign that Mudung fever is waning, it seems this bouncy pig is more than earning her keep. Forced out of their land and hunted to near extinction in the wild, but in captivity, absolute slay.
San Diego Zoo, you know, fantastic zoo. When I used to go with my kids and we'd be standing at the pygmy hippo, people would say, oh, these are just baby hippos.
Oh, that's got to be infuriating for you.
What did you say? I corrected everybody, whether they wanted it or not. But they do look, honestly, to me, they look very different. But I can understand why people maybe think they're the same thing, only smaller. So for everyone listening, they're absolutely not. Pygmy hippos are a separate species. And actually, evolutionarily, they split. from common hippos like millions of years ago.
Really? Yeah.
So it's convergent evolution? Yeah. And a lot of the structures that they have are not that similar. But one of the things that I know people sometimes get fascinated about common hippos is that they are most closely related to whales and cetaceans. No. No.
That's true? No. That is 100% true. No. What? That's right. Common hippos, the big ones you're used to, they're most closely related to whales. Whales.
Yes. And we know this from all lines of evidence. It used to just be morphology, morphological evidence, and they did looking at fossils and different parts of the animals. But as Science progressed and we started using genetic information. They've used all sorts of genetic tests to demonstrate that they are in fact sister taxa, cetaceans and hippos. No.
I have so many questions. Mouths. Mouths. I'm thinking like baleen, huge, insane mouths on whales and hippos. Why are mouths so big?
Why are their mouths so big? That's a good question, actually. So pygmy hippos don't have the gait like common hippos do, right? Common hippos have like 180. They can actually open their jaws that much.
Unhinged, you know?
And it is a good question why, because it's not like they're eating pumpkins and big things in the wild. I will say that male hippos, sometimes you'll see male hippos engaged in what looks like, we're going to say like this mortal combat. I don't think it usually results in mortality, but they do use their gape
both, I think, against other hippos, you know, if they're having a territorial fight, and other animals. They're pretty badass. How big are their teeth? Well, so they have different types of teeth. They have sort of molars, and then they have canines, which come up, which can be 9 or 10 inches. And then they also have incisors. The canines are actually most similar to elephant tusks.
What are they used for? Again, it's probably just some type of defense.
That's so much tooth for someone that eats grass. So much tooth.
And it's a bummer for them because those canine teeth actually do have ivory. Oh. So it's not as high quality as elephants, but it's one of the reasons that hippos have gotten wrapped up in the ivory trade. or legal ivory trade is because they're canines. So those are the ones that are sort of the curved ones coming out of their bottom jaw have Ivory, made of ivory, yeah.
These tusks, these mouth harpoons, grow their entire lives. And the bottom incisors, they jut straight out for better stabbing. And though females do have smaller teeth than the males, male tusks can be over 20 inches long or 60 centimeters. Why so big? Because they use them to gore the mouths of their rivals in this spitty, bloody jab battle. It looks like chewing on glass.
Now that I know that they are sister taxa to whales. Yeah. Swimming. How are they swimming? They got no flippers. What's going on?
All right. You ready? They aren't even swimming. No. They can't swim. They sort of glide, walk, run along the bottom. So they're never in deep water? They can be in deep water. They can be submerged. They can stay under for about five to six minutes, but they're not actually swimming. I guess if you think about like if you were doing aqua aerobics.
I was just going to say, this is like going to the Y. What? Yeah. Don't try this with them, but it is just like that.
And so how are they underwater for five or six minutes and what occasion do they have to use that feature? Yeah.
Yeah, that's a really good question. What are they doing under there? So one thing, remember we talked about them being related to whales. They have nostrils on the top of their... So if you look at a hippo, let's see, how do I describe this?
So essentially your nostrils face your feet, right? Don't put your fingers in there, but you know they're facing your feet. They're pointing down. Hippo nostrils are like on the top of their head and they're facing the sky. Like, you know, Shrek's ears? that's like their nostrils. But they also have ears that look like Shrek's ears.
So they kind of have like a Shrek's ears for ears and then a small Shrek's ears that are actually their nostrils. It's just unsettling. I like it.
And they actually have muscular and anatomical features that are similar to blowholes. So the nostrils close when they go underwater. And when they come up, one of the ways you know that there's a hippo there is because you hear the right, when they blow out. And so that's similar to what we see with cetaceans, right, when they come up and they're blowholes.
So there's actually some characteristics of their nostrils that are similar to that. What do they do underwater? It's hard to know because we really, it's very hard to see. Jacques Cousteau famously like put this fake hippo and people have tried this, like deploy like a autonomous, you know, vehicle in the water dressed up as a hippo.
Bernard touches a fleeing hippo. and then cannot resist petting her baby. It was not a very good idea.
It doesn't go very well for the daughter of the vehicle, right? The hippos are just like, no, get that thing out of here. So it's pretty hard to see what they're doing. And mostly they're in water that is not clear. You can't see anything.
I was going to say, it's like a chocolate river. That's right. Hippos killing people. let's talk about it because they cause more human fatalities than sharks, which we, as if we don't have it coming, like we have a coming so hard, but how are they lethal?
I do want to say as I, because I think I have to represent for the hippos on this one, that more hippos die as a result of hippo human conflict than humans, which is not to underestimate the devastation that happens when there's a fatality, but I don't think hippos are naturally aggressive to people. The biggest threat that they face is habitat loss. They rely on fresh water.
We rely on fresh water. We want to put a farm next to a river because that's where it's easy to grow crops. That's where they live. They're obligate in the water. They have to be there. So it's not like they can just pick up and move. There has been an increase in hippo human fatalities recently. And I think it's really just an indication of habitat loss.
So what's the source of all this drama? Surprise, it's us. Do those happen with overturned boats or bites or how does it?
Yeah, it definitely happens with people fishing in boats. It happens with tourists in boats. It does sometimes happen on land because hippos are crop raiders. Turns out they love eating. We just said they love pumpkins. If you plant some, they'll come eat them. It's not usually pumpkins, but like corn or beans. They do a lot of crop breeding to their defense.
You put the food right next to where they live.
Yeah. It's like donuts in the break room. What are they supposed to do?
Yeah. And much higher quality nutritionally than anything else that they're eating. So it makes sense to them. But it's a definite problem and it's really tough to develop deterrents. you know, people talk about electric fences, but a lot of this is happening in places where there might not be electricity or a lot of infrastructure.
And so it's a real challenge to figure out how to get hippos and humans to coexist.
How are hippo numbers? We know that the pygmy hippo is not doing so great, but how are hippo numbers in general?
Common hippos are in 38 countries. And so it's a challenge to to get all that information. But our best guess is probably something around 130,000, which is not a lot. In the world? Yeah. I mean, well, recently we only count the ones in Africa.
So aside from zoos, are there hippos outside of Africa? Oh, we will discuss.
Yeah, in Africa. And that's about probably a third of the amount of elephants that we have. And so it's a real issue. And the problem is when I would tell people, oh, I study hippos. First of all, that's crazy. And we're concerned because their numbers are declining.
If you're in a place where there are a lot of hippos, someone's going to turn around behind you and be like, excuse me, do you see that large group of like 50 to 100 hippos? But they aggregate. And so it may seem like there's a lot of them, but there's been a tremendous amount of loss of habitat. And, you know, 130,000 is not very many.
Yeah. I would have thought there were millions out there. Yeah. And when it comes to distribution, 38 countries is so many countries. But if you had a map of the world, where do we think they are that they're not? And what would surprise us about where they are? Like when it comes to their range, what do most people think versus what's the reality?
Yeah. I think most people know, like I said, sort of East African countries, Kenya, Tanzania, Uganda, Zambia, South Africa, Botswana has a lot of hippos. The place that we know hippos are probably most vulnerable right now is West African countries because there's much more population growth, less habitat for hippos, a lot more pressure on freshwater resources.
And so I think there's probably people in countries like Nigeria or Guinea or Guinea-Bissau that they may not even know that they have common hippos because they exist in such low densities.
And Rebecca says that while there are only two species, there is debate about whether up to four subspecies exist since West and East African hippos are so isolated from each other geographically.
And there's some disagreement of whether there are or aren't subspecies. But there are potentially as many for subspecies.
When you say disagreement, what is that like in the hippo community? Are there conferences? Do people not speak to certain colleagues anymore? What are hippo people like?
There aren't very many of us. And part of it is because hippos are really hard to study. They're these animals that are hiding in plain sight. They're in the water during the day. It's very difficult to tell them apart, right? With elephants, we have big ears that you can identify individuals and you just can't. And they're just not on a lot of radars for conservation organizations.
So they haven't gotten a lot of funding. The hippo community is thin on the ground. Oh. Well, you mentioned big ears.
Why do they have such tiny ears?
That is a good question. We don't really know, but it could have to do with the fact that most animals that develop in the water, like sea lions, have pretty tiny ears, right? And so I think we don't tend to see animals that have, you know, come up evolutionarily in the water with big ears.
I guess there's a reason we don't go swimming in gowns. Exactly. You don't want too much drag. You mentioned the nostrils being like blowholes. The Jungle Cruise at Disney. You've been on it?
I have been on it.
You're not far from Anaheim. What I recall from that ride is that there's a lot of puns. I believe there's some racism in it, but also there's a depiction of hippos as like nature's ultimate predator. Do you recall anything about that? I do.
It looks like the hippos are going to attack the boat, but I'm going to scare them off like I did my last relationship.
I don't remember engaging too many people, but I certainly told my whole family and the people I was with, this is not accurate. There's a lot of that. The one thing people ask me when they find out that I work on hippos is kind of where we started. Do they really kill more people than any African animal? I don't know who started that, but it certainly wasn't me. And I don't think it's accurate.
It is not fact-based. I think snakes kill way more people than hippos. I think the reason it started sort of this urban legend is because it's surprising. It's surprising that for people to know how fast they move on land. And the answer is faster than us. You know, maybe 19, 20 miles an hour they can run. They can move extremely fast in the water.
And I think that there has been an increase in hippo-human conflict. And that takes people by surprise because they're not particularly aggressive, I think, naturally. I think what we're really seeing is habitat loss. They're under tremendous pressure. And so the number of attacks is on the rise. But I just want to tell people now, I don't think hippos kill humans.
more people than any other African animal.
I mean, hello, mosquitoes.
Yes, exactly. That's who started this whole thing. It was the mosquito lobby trying to point the finger at hippos.
It goes like, we did a mosquito episode recently, and it's like, mosquitoes, other humans... Yeah. Snakes, like dogs with rabies, like whatever. Humans and mosquitoes are the ones you got to watch out for. Absolutely. Can I ask you patron questions? Yeah. Okay. Your questions about hippos in a moment, but first we're going to fling some cash at a worthy cause.
And this week it's going to Weichau Community Hippo Sanctuary, which is a community-led tourism attraction project. It's located at Weichau in the Upper West region of Ghana. And they say that hippos help regulate both aquatic and terrestrial habitats and are great ecosystem engineers. So it's a great cause to find out more. You can go to wilderinstitute.org. The link is in the show notes.
So thank you for the heads up on that, Rebecca. And thanks for the money, sponsors. Okay, your questions. You can submit yours via patreon.com slash ologies. It costs one hot dollar a month, although the upper tiers let you leave us audio questions. So let's dig into the bag and let's get those answered and find out how to make hippos happier. Deborah Brunner said...
Sadly, everything I know about hippos is from the Jungle Cruise at Disneyland. So I was wondering, is it true that hippos are really only dangerous when they're blowing bubbles and wiggling their ears?
I don't think that's true, Debra. Okay. I think bubbles and wiggling is not the thing you have to worry about. I think the real thing you have to worry about, people ask me like, what do I do to sort of like fend off an attack? And you know, the answer is like, wait, why are you in a place where hippos can attack you? The thing we need to do is avoid them and not be in those spaces.
Now, if you're a commercial fisherman in an area that has hippos, you know, it's a different situation, but most of us aren't.
So yeah, here's an idea. You don't want to see the sharp end of a tusk. Stay out of the river. If a hippo picked a lock and arrived in the middle of the night in your living room, dripping with river poo, would you not grab the baseball bat between your bed and the nightstand and ask it in no uncertain terms to scram? I know you would.
Speaking of certainty, do hippos know when they've found the one? Steph Simmons, Ann Arbor, Michigan, asks,
I'm wondering if hippos are monogamous. Do they mate for life?
No, they are not monogamous. They don't mate for life. And in fact, they don't really form bonds like that. So hippos are something called polygynous, which means there's a single male, the dominant male, and lots of females that he probably mates with. Hello, ladies. And that herd is like that, sort of with one male and lots of females until...
another dominant male comes over and challenges that hippo for that territory so when you see the you know national geographic pictures of two hippos with big gapes sort of going at it with those big teeth we were talking about like what those are for those are territory fights for control over one of those polygynous herds got it they're kind of like in a bar fight
A little bit. Yeah. They're showing off a little too.
Exactly.
Amanda and Eli Loves Vultures both want to know, Eli says, I love hearing scientists describe animal sounds, wheezes and honks and croaks. Oh my, what do we know about the sounds they make and what don't we know? That is a great question.
And the answer is we know almost nothing about hippo communication. Why not? They're communicating in the air like we are, but they're also communicating in the water. And we don't really understand how they're doing it. We can record them. And people have done that. And they describe sort of clicks and other types of noises underwater.
Yeah.
Like that, right? It's not a great one. I'm probably not going to call them in. But I think it's these crazy noises. And we really don't know anything about what it means, what they're saying, how they're even communicating in the water.
I so appreciate that you're able to mimic them like that. Do people ever try to get them to come to them? No one that I know.
I think it's interesting because honestly, it just feels like one of the wonderful mysteries of hippos, but it's also one of the things that's kept them, I think, off the radar and kept them sort of in this area of we see you, but we don't know anything about you. It's just that they're so tough to study.
We need more hippopotamologists. We absolutely do. Several listeners asked this question that was absolutely not on my radar whatsoever. Amanda Nugent asks, is there a plan for the cocaine hippos in Colombia from Escobar's estate? Kayla White, all caps, all caps, no punctuation, said, please, please, please talk about Pablo Escobar's hippos. please, it's my favorite story to tell new people.
It will be your new favorite story, especially for inquiring patrons, Alan Gross, Stephen Lee, Teresa Gleason, Kristen Love, Matt Goff, Jen Squirrel-Alvarez, A Softly Boiled Egg, Christina Hammerberg, Lucy Vinn, Sigwani Dana, Gregorius of Tomsk, and Pavka34, who needed to hear about these cocaine hippos.
Yeah, it's a really crazy, crazy thing. So if you're just new to this, Pablo Escobar, who is a very famous narco trafficker, had four hippos, three females and one male on his ranch and compound. And upon his death in 1993, for some reason, they just left them.
Okay.
Cut to this many years later. And now there's probably around 200 hippos roaming wild in this area of Columbia called the Magdalena River. Turns out it's a great place to be a hippo. Oh, no. So hippos do really well under good conditions. It's one of the reasons why hippos can start having babies like four years earlier in captivity. It's because the conditions are so good.
So that's what we think happened in Colombia. There's grass everywhere. It's never a dry season. They never lose water availability. There's unlimited food, unlimited resources, and that's why we've seen this population explode. So what do we do now that there are 200 and maybe more hippos in Colombia? It's a really tough problem.
There have been some suggestions and solutions that they've tried, but all of them take a lot of money. They've tried darting some with contraception. They've tried castrating some of the males. They have actually culled one individual, so they've shot him. And that may sound terrible to some people, and I'm obviously not
concerned about hippo welfare, but I'm also concerned about the welfare of Colombians who live there. And there's lots of rare and endangered species in Colombia. There's no easy solution here. From my perspective, my focus is on protecting hippos in Africa. And that's where we need to be focusing our resources.
So the idea of people have talked about like trying to send them to captive facilities, but It doesn't feel like a great use of resources to me because that's not really where they're supposed to be at all. The only reason they're there is because someone had hippos as pets.
I guess this sort of dovetails into the question of meat. Rebecca Morrison, Tinaz, Michael Sherman, Daniel Schmaniel, Jess Sunter, several people asked, do people eat hippos?
They do. And I never have. I'm a vegetarian, but people do eat hippos. There are some groups of folks who have taboos in certain countries, in certain areas against eating hippos. But in most of the places where I've been, people do eat them. They have very thick fat layers and sort of like pigs. And I've heard that they are extremely yummy and, you know, people eat a lot of the parts.
And so that's a lot of meat for a lot of people.
And a few listeners, reigning Emily and Andy Pepper, hoped that I would bring up what patron Mackenzie King wrote instead of a question, offered, this feels like a great place to drop the fun fact I have about hippos. Mackenzie writes, in 1910, Robert Broussard, a Louisiana senator, proposed that hippos be imported from Africa to Louisiana to be the new version of beef in America.
This was due to corporate beef monopolies, beef shortages, and super high prices on beef nationwide. I was like, whoa, Raining Emily, Andy Pepper, and Mackenzie, I didn't even know about this. So yeah, the American hippo bill was introduced by Robert Broussard, or as fellow Louisianans called him in the early 1900s, Cousin Bob. And though he had the blessing of Teddy Roosevelt...
New York Times food writers who attested that hippo brisket was fatty and tasted like lake cow bacon. And Broussard even had the support of some ecologists looking to solve the invasive water hyacinth problem that was plaguing New Orleans.
New Orleans.
Alas. As you know, no swamp hippos lurk in our dark American waters. Our sprawling Bass Pro shops don't sell hippo calling devices to locals. We don't get to see invasive hippos learning to use crosswalks or trying to mate with hot dog carts. But yeah, in other countries, if they got a hippo, they may eat a hippo.
And one of the threats to hippos is unregulated hunting. And in large part, it's because they just sit in the water. You can take them out with a muzzleloader, you know, an old gun. They're just sitting right there. And then you have 2000 pounds of meat. So in some places where there's been civil unrest or really hungry people, which makes a lot of sense, right?
Hippo populations have declined dramatically because people have needed to eat them to survive.
Allison Ledman wanted to know, are there any other animals besides humans that prey on hippos? Or do predators just know to steer clear?
In general, I think the only predator they really are concerned about is people. They're not worried about crocs. That's when crocodiles, that's the question that comes up. People ask, oh, you know, crocodiles eat baby hippos. Crocodiles do not stand a chance in the water. Oh, really? Mom hippos are extremely protective.
as moms are in lots of places, that there's no chance that the crocodile's going to get them. I have seen lions taking down juvenile hippos, so I know that it happens, but I don't think it's particularly common.
Crocodiles can't even get them. A crocodile will shred your ass up and down and drown you as casually as eating a Snickers, but they can't fight off a hippo. Who would dare? Not many creatures. If they don't have a ton of enemies, do they have a lot of friends?
Like Marissa Kay, first-time question asker, long-time listener, very excited about hippos, would like to know a little bit more about their social structure. Risa Pereni wants to know if they ever cuddle. Do they pair or live separately?
And patrons Mona Finlayson, Prani Kiritsingh, Storm Kitty Hammond, Colin Robotten, Oliver Callis also asked this, and in Bronwyn Iverson's Hugo's words, do they have best friends?
The one best friend I can think of is a really cool mutualistic relationships between hippos and oxpeckers. So if you see hippos that are out of the water or just partially submerged, you'll often see a particular type of bird that sits on them. It's called an oxpecker that actually eats like ticks and other insects. So the bird gets free lunch and the hippo gets cleaned.
So that's definitely a friend. In terms of their social structure, I think they are really social animals themselves. We don't understand like who's related to who in those herds. Again, we can't barely tell them apart. And for most people, unless you spend a lot of time looking at hippos, you can't even tell males and females apart unless they open their mouths.
Their canine teeth for the males are much thicker. Their head structure is different, but like they're not sexually dimorphic, right? Sometimes males and females are really different sizes or different colors. They're all gray. They're all fat. They're all really big and you really can't tell males and females apart when they're mostly submerged.
Sometimes you'll see like creches, which is like groups of females and lots of offspring, like lots of calves, and they can play together in the water. But again, that's because there's these big groups where it's one dominant male and lots of females and their offspring.
You know, speaking of males, people asked about Rob Lara, the poo helicopter, why? Lena Carpenter wanted to know, how do hippos just poop in the water? Like, the water they're in, and then proceed to swim in it like no big deal. Boy, hippo poop spraying, disgust. Do they have middens? Do they just go wherever? There must be so much of it.
That is definitely true. There is so much of it. And we actually think that hippo poop, and not just the poop itself, but all of the compounds like silica and silicon that's in there, are really important nutrients for the water areas, the wetlands, the rivers, the lakes where they live. And there's some evidence that when hippo populations decline, fish populations also decline.
Thank you, patron and first-time question asker Allison Ludwig for asking, do tilapia really swim behind them and eat their poo? Allison Ludwig, they do. So yes, Emily Gee, Ashley Tween, and Rowan Tree, there are symbiotic relationships aplenty in a hippo's life. And so to Gits and Shiggles and Emma Henson, who asked, I have to befriend one before I die. How do I go about this?
The answer is to become a tilapia. You're never going to be bored. You're never going to be hungry. Every day is a feast.
It is true that hippos, when we ask, like, where does a hippo poop? The answer is anywhere it wants. Mostly it is in the water. But with males, we do see that marking behavior. Another crazy thing. Ready for this?
Not really.
So what males do is they come out of the water, they start peeing, and then they spray it backwards. And then with their tail, use that to spread with the stream of the pee and the poop coming out. It's gross, and yet extremely effective. And I think it's territory marking, although we don't really know this, because we really only see males do that.
So we think they're marking their territory, you'll see it as they come out of the water, they kind of do this at a couple places, sometimes they'll smush it against like a tree, or, you know, a rock. And I and we think, again, we don't know this for sure. But we think it's dominant males marking their territory.
Oh, my God. Yeah. Which I've seen it in people's like horrified zoo videos. But I hope that that's like a blessing.
There's just spreading the love, right? They're spreading what they do best. And it is one of the things they do best. They're really important nutrient movers and ecosystem engineers in that way.
Stacey Bendixson wants to know, do they sleep underwater?
No, mostly when they're sleeping, they're resting above the water. So I remember I was thinking like, imagine there's sort of a log, that's the hippo's head. And so mostly when you see them resting, it's they're resting on the bottom. And that's one of the reasons why their nostrils are really at the end of the log, that's their head, is so they can breathe that way.
So they're only underwater, again, at like five to six minutes, maybe max at a time, it could easily be less. They're not sleeping underwater.
Okay. There's no way that they could lung capacity wise, but in general, they're not like snoozing in a pile on the banks though.
They look like logs, honestly, when you go to an area where there's a lot of hippos. And so there's sort of this like small top of the log, that's the hippo that you can see. That's them just sort of And actually I should say, are they sleeping? I don't know. They're certainly resting.
We don't 100% know what they're doing when they're in there in large part because it's not safe for us to get in there and find out.
Do you think that scientists are starting to rely more on like drone footage? Is that helpful in terms of getting kind of closer to them and getting like a better eye on them?
Absolutely. It's an amazing technology that I think has changed a lot. One of the reasons that it's so hard to find out how many hippos we have, that seems like such a simple thing, just go count them like elephants. The problem is when you go do a flyover, right, you take pictures, that's one of the ways that we count, you know, animals in remote areas.
At any one time, there could be 30 to 40 percent of the populations that submerged. Right. They heard a noise and they got scared. And so now they're under the water. So you can't see them. And so drone technology has been amazing opportunity to be able to really count hippos and just get some basic questions like how many are there? Where are they? How are these numbers changing?
And I know it sounds really basic, but. for something that's the fifth largest land animal, we still don't have great data on that.
In terms of the word, the beach master, are you, you're familiar with that term? Is it, there's a really long time ago, a documentary about hippos, and they talked about how there's a beach master of hippos.
or the beach master, a spot in the deepest part of the river is worth fighting for.
And I wasn't sure if this is like a very common term for hippos, and this is just a side note, but that term has stuck around me and my good girl friend groups for decades now, where the beach master is the one in our friend group who now has to decide like where we're going to go to dinner, or someone needs to beachmaster this because I can't deal.
But I wasn't sure if beachmaster is like, no, that's what we call the dominant male. But no, beachmaster is not a familiar term.
It is not a familiar term with me, but it does kind of make sense. There is certainly a dominant male. And again, people always say like, well, where are the rest of the guys? The rest of the guys live in a bachelor herd at some distance away from the rest of the herd. So it's literally all the other males. So
at some point juveniles get kicked out of the main pod and they have to go with the bachelors. And that's where all the other adult males go that aren't the dominant male. So you can find a bachelor herd that's associated with a large polygynous herd.
It reminds me of like on the bachelorette when one gets a one-on-one date and the rest have to hang out at the mansion.
That's exactly it. That they're waiting for their roses. They're waiting for their turn at bat. And they, might challenge that male, right? And that's when you'll see those cool sort of like big gaping fights where they stand off and, you know, fight on the beach. So maybe that's the beach master.
Do a lot of hippo males divergence? Excellent question.
It's very challenging to know how much sneaking there is, right? For a lot of species where there's like a dominant male or even monogamous couples, there's still extra pair copulations, we call it. And I don't know how much sneaking there is. So it's possible that those bachelor males sneak and get access to the females, but we don't know.
And that's something that if we could get like tissue samples or be able to do genetic testing to be able to kind of figure out lineages or which calves are related to which parents. It's so hard to get to them. And it's almost impossible to tell them apart. Hippos just don't have any structures. It's rude probably to say they all look alike, but to our eye, they really do.
When it comes to trying to get DNA samples, their skin seems so thick. You can't just run a Q-tip over their skin and get samples, right? You've touched hippos?
I have touched hippos in captivity. I have touched dead hippos. I have not touched a live hippo in the wild. I've never been that close or in, you know, I wouldn't do that, but it's a great question. Like, how do we get samples? Another question is like, why don't you just put a collar on them? What's the big deal? Go figure out where they go on the collar front.
Turns out hippos don't have a neck. Most of the collars go around the neck. They don't have a neck. What they have is a head that's attached to the rest of their barrel-shaped body. You can't put a collar on them. So most of the technology that we have for tracking rhinos or tracking elephants won't work on hippos.
In fact, a colleague of mine, the first tag that we put, and it wasn't a collar tag. It was like a tag that they attached... just on the skin, wasn't until 2013. And it stayed on for like a kilometer. Amazing feat, but really, really hard. So hard to figure out where they're going. And to get samples from them.
The other thing about hippos, remember we talked about they're amazing from head to tail. They have one of the thickest hides or skins of any animal. hands down. In fact, people used to use hippo skin to make whips because they are the most durable and hardest. So actually even getting a dart or something like that into a hippo, very, very hard.
But they're not a pachyderm.
They are not. Nope.
Apparently, a hippo hide can be two and a half inches thick or six centimeters, which is comparable to a very robust slab of kitchen countertop or a butcher block made out of wet leather. And speaking of leather, yes, you could buy, say, a wallet made from hippo skin. And it looks kind of like... thick, crackly suede.
You could buy it, that is, if you had $99 plus tax and shipping and you wanted it. Now they are, I found some, they're handmade in Indiana by Amish craftsmen and their website has images demonstrating like it's billfold and slots for up to eight credit cards. And I was scrolling to the bottom of the description and I spotted this small disclaimer that said, money and cards are not included.
And I'm like, They must have gotten one email from a customer who was just enraged that theirs arrived empty. But from seeing red to being tickled pink, what a segue. Let's discuss a question from... So... Speaking of their skin though, sweating blood, what's the deal? Do they sweat red? Is it sunscreen? What's going on?
They don't sweat blood, but it is sort of a reddish orange pigment. And that is something that people have isolated because they were able to get it off a captive hippo. And a fantastic group of scientists from Japan in 2004 was able to extract some and figure out like, molecularly, chemically, what's going on here. And it's just, as you said, it's not blood.
It is a secretion, but it is a sunscreen and probably an antibiotic. Oh. And we think that that secretion both protects them from the sun, which we know is very important. We talked about hippos, the need for water and important for their thermal regulation, but also that secretion seems to be an important antibiotic.
I want that a little bit.
I wish I had it, right? I could really use that sunscreen.
Right? A few Mudang questions because, of course. She's the cutest, cutest.
Who could resist this face? Certainly not these huge crowds lining up at a zoo in Thailand to catch a glimpse of two-month-old Mudang. That's Thai for bouncing pig.
Bell Aspiring Garbage Archaeologist asked, is it common or somewhat out of the ordinary for a baby hippo to be as ornery as Mudang? No shade, I wish I could be as ornery as Mudang in public, they ask. Is Mudang ornery for a young pygmy hippo?
You know, I've asked for a couple other places. Like she does seem to have a very lively personality. Nothing that she's done that I've seen, it seems like out of the ordinary. Anybody who's taken care of kids, like they open their mouth all the time. They're pretty demanding and they want attention. And she seems to be extremely healthy and just, you know, a lively pygmy hippo.
What about... some controversy regarding Mudang. Jennifer Gorgon said, I heard there was some controversy about the treatment of Mudang. Do you have an opinion on the issue? Anna Vilnide wanted to know, would love some professional information. Are caretakers riling up some captive animals for the reactions that visitors want to see, they asked.
And whether online content being the goal is harming the creatures that we seem to love so much. And Natalie Jones asked, is Mudang doing okay? It seems like having thousands of humans yelling and looking at you a day would mess up a baby's development. Is this a stage mother type of situation that needs intervention?
One thing that's been wonderful about having Mudang on the scene is that people know about pygmy hippos. And a lot of people maybe didn't even know they existed. They're not just smaller common hippos. This is a separate species. It's endangered. And, you know, I think This will be the only opportunity for most people to ever see a pygmy hippo.
In fact, even people who study pygmy hippos, again, we only got pictures of them in the wild in 2006 from remote cameras, not a person with a camera, a camera out there by itself. There's so much we don't know. And I think that having more people aware of pygmy hippos is great. The thing that really upset me about the story is knowing that people threw things in the enclosure.
You know, there were people throwing shrimp or other types of food. And hopefully everybody who heard that story realized that's the thing that's a danger. Like you can never throw anything into an enclosure that has a wild animal. You may think you're doing you know, something good, but they have a very strict diet.
And I think having folks being respectful, you know, being quiet is a great thing when you go see animals in captivity because it is stressful and it is important that we're mindful of what their experience is like. So I appreciate those concerns.
Okay.
Last question from listeners. Kate Cavanaugh said, Hi, Allie. This is Kate in Wake Forest, North Carolina. I served in the Peace Corps in Botswana where I was lucky enough to see hippos in the Okabanga Delta. I'm wondering what your ologist thinks might happen to these specific populations given climate change and upstream development in this region.
Thanks. This is a really important point to talk about, which is We talked about hippos being threatened from habitat loss, which is just us encroaching, developing areas around freshwater. But climate change is another real serious threat, particularly for common hippos, but probably pygmies as well. But they rely on water resources.
And a lot of the places, a lot of the projections of where we think what's going to happen, it means less rainfall, less standing water. I think it's a real threat. it's getting closer as we think about like ensuring coexistence of people and hippos into the future is the fact that the climate is changing and they are so sensitive to these climatic shifts.
So I would say when we think about like winners and losers of climate change, I would put hippos in the loser category, you know, and it's something that we absolutely, it has to be on our radar because these are the resources that they need.
Yeah. Is there any flim flam that you just have to bust that you're like, this is not how it is, other than painting them as absolutely cold-blooded killers who want nothing more than a human's demise?
Yes. The whole they kill more than anyone else. If I can do one thing in my lifetime, I feel like it's dispel that. Why? No, it's not right. It's not accurate. Stop saying it. The other flim flam, I guess, it's really just this idea of like, oh, there's so many of them. It's not true.
Like I know that they are abundant and they come in these big groups, but they're really declining in a lot of places. And even in areas where their populations may be stable, they're losing habitat, either directly from human development or because of climate change on slightly longer scales. But I think that's a really important one. And I care about elephants too.
Like I sometimes come across as like grumpy about elephants. But if I am, it's because elephants just get so much attention. And I know they have incredible behaviors and they, you know, mourn their dead and they communicate where we can't hear them and amazing things. But I think hippos have all of these things too. It's just that we can't see it and we don't know it.
But they're these incredible animals, certainly worthy of a future.
What's the worst thing about being a hippopotamologist?
I think the worst thing is just that expectation of, oh, well, we know everything, but we don't even know how many there are. Like basic, basic things. And that's sometimes frustrating because, you know, you kind of have to start the conversation from the scratch. And so studying hippos is about studying human coexistence with them.
And I'm really hoping that the next generation of scientists can use that technology to really think about innovative ways of to protect people and protect hippos and their habitat.
What's your favorite thing about hippos?
I honestly am captivated by them sort of as these like organisms. Like I said, I am fascinated by all those adaptations, all these things about their body, whether it's their teeth or their stomach or their skin. It's amazing. And it feels like every time you sort of look under another part of the hippo hood, they have another incredible adaptation to being these
semi-aquatic sort of like half whale, half antelope, you know, and that's incredible to me. And I still find myself captivated. I mean, even though I've been studying this for a long time by those adaptations, by all of the things that their bodies are able to do and navigate.
If there were ever one sleeping next to you, would you want to give it a gentle kiss on the nosy?
I would. I know better. We don't touch wild animals in the wild, but they're incredible. So yes, I can safely say that if I happen to find one next to me that just wandered up and I could touch it safely... I absolutely would.
I wonder if they know how much we love them. That is a good question.
They probably don't give a hoot about any of that, but I would love that if that could really translate to people's passion of saying, I want to live in a world that has hippos, that has pygmy hippos, common hippos, and I want to know that they're going to be here for a really, really long time.
Yeah. This whole episode has convinced me that we're in a toxic relationship with hippos. We're the toxic partner because we fawn over them. We love bomb them. And then we take what they need most. We take their habitat and we spread lies about them and then we slander them. So if anything, if you love hippos, just know you're the toxic one in the relationship. Clean up your act a little bit.
It's you.
It's not them. Yeah, absolutely.
So hippo people, happy to answer questions. And we're so very lucky that Dr. Lewis was amenable to answering ours. Thank you again, Rebecca. And you can find links to her research and lab as well as to the Weichau Community Hippo Sanctuary at the link in the show notes. And we also have a link to our new show, Smologies, which are shorter, kid-friendly, classroom-safe versions of Ologies Classics.
They used to be in this feed, but I bounced them to their own feed. So you can look for that show wherever you get podcasts. It's got new green artwork. We are at Ologies on Blue Sky and Instagram. I'm on there as well as Allie Ward. What's just one L in Allie? Thank you to patrons at patreon.com slash ologies for making this show possible. Ologies merch is available at the link in the show notes.
Thank you to Aaron Talbert for admitting the Ologies podcast Facebook group. Love to Mama Kath. Aveline Malik makes our professional transcripts. Kelly Ardoire does the website. Noelle Dilworth is our scheduling producer. Susan Hale is the beach master of a managing director. Jake Chafee edits like a
hip pro and the mighty Mercedes Maitland of Maitland Audio lead edits these into submission every week. Nick Thorburn moaned and honked out the theme music. And if you stick around to the end of the episode, I tell you a secret about my life if you want it. And okay, so this week it's that I wear one of those rings, an aura ring, which I've used for years.
But an aura ring helps track sleep and your steps and stress. And no big shocker, I've started meditating again literally just in the last week. Um, my soul feels like a hairball in a drain over current events. And I can tell on my aura ring that when I do meditate, my heart rate and stress levels go way down. So that is great incentive to like keep at it.
And I was going to tell you guys that is a secret. And I looked at my app today to see like, yeah, it did go down this morning when I meditated, but I also saw this really sharp spike, um, in anxiety today. And I looked and it was like two hours ago and, And I realized it was precisely the time when I spilled a quart of fish soup on my pants and the kitchen floor and inside the fridge.
It was like everywhere. And fish soup of all the things. Iced tea, whatever, fine. Fish soup, like, honestly. Anyway, anxiety spike, deep breaths. We're doing our best. We're all doing our best. I hope you enjoy a nice bath today like a hippo would, or you could treat yourself to a big mud salad. Whatever keeps your skin thick and your spirits buoyant. Go do it. Okay. Bye-bye.
the beach master retains his deep-water kingdom for now.