The Fascinating Lives of Bleeding Heart Monkeys (Part 1) | Nat Geo Live

So National Geographic asked us here tonight to tell you about a day in the life of gelada monkeys and what it's like to live alongside them. For the past decade, the vet and I have spent years living alongside this species in a unique kind of alpine out-of-the-way corner of Ethiopia. But before we get too far into monkeys, we need to start with geography because this is the key to understanding the species' success. And we're at National Geographic, after all, so we kind of have to start with this.

If we look at this, we have a map of Africa, and you can see this is an elevation map of Africa. If we just highlight the mountains in Africa, you'll notice a pattern emerges right away: They all cluster kind of into the east. You might think of Kilimanjaro when you think of mountains in Africa, but that's just a speck on this map. Eighty percent of all mountains in Africa are located in one country: Ethiopia. Ethiopia stands apart; it's the roof of Africa.

So this is where Rebecca and I found ourselves a decade ago, living at 11,000 feet out of tents overlooking the Great Rift Valley. It was a big adjustment to a new environment for us, but there was an even larger adjustment that we had to make—adjusting to an entirely new society: primate society. One full of lovers' quarrels, tragic loss, and their never-ending obsession with food. I was a little bit dubious about how this was going to work out when I first got there, but to be fair, the monkeys were a little bit dubious about us at first as well. However, we kind of grew into getting used to each other.

To start off with, this was never part of my own long-term plan. In fact, growing up as a kid, I was interested in a remote region a little bit further north—the Arctic. I read a lot about Arctic explorers and became interested in how plants and animals can survive in such a difficult ecosystem. So as I was finishing up my college program, I started looking for field jobs and came across one that was related to monkeys in the mountains of Ethiopia. I thought, "Hmm, this is interesting. This is a different direction; I'd like to know a little bit more about this."

So I just sent off an email to the other person that posted the ad, and I got a short, you know, kind of terse reply back from a satellite email account. In this, I was introduced to the Guava Gelada Research Project, which was founded by Drs. Peter Fasching and Nia, anthropologists based out of the U.S. I asked a couple of questions, I was like, "What's the deal with this? Can you give me some information? I might like to apply." And so Peter wrote back, he said, "You know, thanks for your interest. This is a position for no pay for one year, so we moved to a really remote part of Ethiopia. The climatic conditions are pretty tough here, you won't have much contact with your family, and the food situation at campus is kind of bland, but..." And he really sold this part: "We have a solar-powered fridge that you can start treats in if you really want, but the fridge is also full of fecal samples, so you have to really wrap them up really well."

It's very earnest about this: "It's like, 'Okay, well, you know, this sounds kind of intriguing.'" And then he had this other comment, "It's beautiful here." It's like, "Okay, I think you've ticked all the boxes; maybe it's time for me to apply." And so he asked a couple of questions of me: "What kind of research experiences or winter camping or whatnot do you have that make you feel qualified for this position?"

So I grew up in suburban New Jersey, had never been camping before in my life, and I'd done a research project on squirrels before in college. So I threw my best pitch together and sent it off over the satellite airwaves, and somehow a couple of weeks later, I had a ticket booked to Ethiopia to arrive in Addis Ababa a couple of days after my college graduation.

So a little insight into my psyche at this time point in my life was revealed. Well, it's kind of digging through all the emails to prepare for this talk; this is the final email that I wrote to Peter, you know, this PhD biologist that I had never met before, and I really wanted to impress. I signed off like this: "That's about all for me. I'm off to Taco Bell for maybe the last time this year. Let's hope I won't need that anti-diarrheal medication earlier than planned. Regards, Jeff." I don't know what I was thinking. It seemed like a good idea at the time, but I really want to thank them for giving me the opportunity to go to this place. And then, upon a little bit further reflection, I thought maybe there weren't that many applicants.

Alright, so in September of 2007, I joined Jeff at the Casa where he had spent the summer. Now, I had just graduated from college where I'd studied physics and philosophy. I'd mostly spent time in the library and the lab, and like Jeff, I grew up in the suburbs. At this point, I also had never been camping. So as I was about to leave for the field, I sent Jeff an email introducing myself, and he wrote back with really long, lengthy replies—details about daily life at the Guava—so full of his thoughts and feelings. He seemed like he was pretty lonely up there.

We arranged to meet at the airport in Addis Ababa, and he sent me a picture so I knew who to look for, which he now knows. So at this point, I basically thought Jeff was crazy. Getting on that plane, I was actually pretty anxious about the upcoming year. But to step back for a minute, that summer of 2007, I had decided more or less overnight that I wanted to become a primatologist—to spend the rest of my life studying primates. It was because of this book by Robert Sapolsky called "The Primates Memoir," where he details daily life in the field in Kenya studying baboons and all the colorful field adventures that go along with it.

But it really wasn't much of a stretch from knowing who I am; I really love animals. I've always loved animals as a kid. Visiting my grandparents in southern India, I would go out on the streets and kidnap baby cows, like you see here, take them back to the house thinking they were common property. And on that very same trip, I actually had my first experience with a monkey. It was at the temple that you see right here in southern India. To make a long story short, I was closely observing a group of monkeys when one ran up to the one that was closest to me, took its finger, and stuck it directly into the butt of that monkey. This monkey turned around horrified, and the first thing it saw was me. So I got bitten in the calf, much to my parents' horror.

I was hoping the experience of Geladas would be a little bit better. As I prepared to leave for the field, I sent Jeff a final email. I said, "You know, you've been in the field a couple of months now; you must be dying for something from the U.S. to, you know, remind you of home." He replied, "I'd like a single pack of Rolo's candy." This confused me; I didn't really take it seriously. I said, "You want maybe five or ten?" He said, "Nope, just one." I was confused, but I realized over time that that's just Jeff.

So we lived alongside these monkeys out of tents in the Ethiopian highlands. We lived next to farmers—farmers who lived in farms that neighbors' Guadas, that look kind of like this. They grow wheat and potatoes and barley, and on our off days, we would be invited to these farms to enjoy their delicious Ethiopian coffee and injera. Here are Shoah and Ben Toka D'su—guys are brothers. They've worked for our project for about ten years now and they've become really close friends. But at first, they were pretty confused about what exactly we were doing because they see Geladas every day. They almost see them as pests sometimes. They said, "You know, why are you interested in working with these monkeys? Why do you follow them around all day and relentlessly pursue their feces?"

The answer, of course, is that we are primates—humans are primates. And by studying our close relatives and their complex societies, we can hopefully better understand who we are. And we also have a duty to protect vulnerable species like Geladas. Some Geladas today are confined to habitats like this grassland that's been turned into farmland. So habitat loss is really affecting the species, and you can see that contrast between the Guava and this picture here.

But now let's think about what it's really like to be a Gelada and a Gelada researcher, and that starts in the morning.

So a day in the life of a Gelada begins much as you might expect, much as we might begin our own days. They slowly wake up and roll out of bed, except for Geladas, their bed is a cliff on the edge of the Great Rift Valley. And they do this because the cliff represents safety for them. That may seem a bit counterintuitive, but it's a place of refuge from predators, where they can sleep.

Fortunately for Geladas, they have incredible climbing abilities. Their short, stumpy fingers let them get up these steep slopes without any trouble, and they don't seem to have any sort of fear of heights. I've seen juvenile monkeys playing right on the edge of precipitous cliffs without seeming a care in the world. And so that's how they begin their day: just with a big climb.

In contrast, researchers and photographers want to get to the cliffs before the monkeys make it to the top; that's when the action starts happening. So we wake up a bit earlier in the pre-dawn chill of the Afro-Alpine Highlands. This means waking up in the frost several days and, you know, grabbing a quick coffee in our kitchen tent and then hustling up this hill.

We start the day in winter clothing, like big puffy jackets, and walking up the field. At 11,000 feet, you get tired and start huffing and puffing really hard and get covered in sweat. A couple of hours later, we'll be walking around in t-shirts, fighting off dehydration. It's a unique aspect of the mountains of Ethiopia and any mountains in an equatorial place where you get summer every day and winter every night. This poses all sorts of challenges to plants and animals that, you know, live in these areas as well. Something from the lowlands wouldn't survive up here, so we're surrounded by specialists, and among them, Geladas stand out as one of the most charismatic.

So they climb to the top of these cliffs, and they bask on the edges of the rim of the Rift Valley for a while. Adult males come up first; they're a bit bigger than the females and they have longer fur coats so they can handle the cool Alpine air. They'll just sit there, kind of stretch, maybe yawn as the sun comes up, and then they're followed by the females and the juveniles. They'll huddle early in the morning when it's cold to preserve warmth, particularly looking out for their little ones.

But pretty soon, the whole herd is right on the edge, and their morning routine begins. So this involves, you know, running their fingers through their hair, sisters cleaning other sisters, looking for little parasites that they'll pop off and then pop into their mouths. They're not just obsessed with being clean; this is a really important part of their day to build social capital with one another. It allows them to build coalitions that, later on, when monkey politics get a little bit complex, come in very handy.

Juvenile monkeys often imitate the older ones but get some of the details a little bit wrong. I'm not sure exactly what this little guy was looking for in there, but I hope he found it—or maybe I hope we didn't find it. But they lose their attention pretty quickly; they'll do a little bit of grooming and then go off by themselves to play.

So this may look like they're fighting, and it's a form of mock fighting. They'll bite each other and tussle around in the dirt, but again, it's them learning about how to act when they're older. Any mistakes they make now don't really have that big of a consequence; if you make the wrong move when you're an adult, however, things can be a bit more dire.

So we focused on the visuals for the moment, but Geladas have their morning routines in the auditory environment as well. Even on days when you're totally socked in by fog trying to figure out where the herd is, you can just follow your ears, hearing them interacting with each other, or, you know, being conciliatory or sometimes a little bit aggressive.

So if these sounds seem a bit familiar to you, you're actually not alone. Almost 2000 years ago, there was this philosopher named Phyllis Sturgis who wrote about the Sphinx monkey, and he described its voice. Now we have a surrogate for Phyllis Aureus here today. Even the voice is similar to human, except that it is not articulate, but it is like meaningless mutterings uttered rapidly in rage or fear.

Now, Phyllis Sturgis also went on to describe the physical appearance of the Sphinx monkey, which we again have a surrogate for. The body is hairy, as in other monkeys, but the chest up to the neck is bare. It has breasts like a woman and low reddish protrusions resembling millet seeds, which surround the naked parts of the body very prettily, fitting in with the human-like flesh color. In the middle, the face is somewhat round, rather like a woman's.

So as you can probably guess, the Sphinx monkey is a Gelada, and even today, Geladas continue to fascinate humans. They remain one of the most charismatic and enigmatic primates—maybe because of the strange way they look and act, or those eerie similarities with humans, or their deep isolation in the Ethiopian highlands. In 1938, National Geographic actually had an article about Geladas. The article called attention to that red patch you see there on the right in the hourglass shape. This is what they named the bleeding-heart baboon.

But the thing is that bleeding heart isn't actually bleeding, and Geladas aren't actually baboons. Instead, they sit poised on their own isolated side branch of the primate family tree, in their own genus called Theropithecus, the genus of grass-eating monkeys. If you were to go back into the African savanna about a half million years ago, you would see basically Geladas the size of gorillas walking around next to warthogs and zebras and such. But today, only the Gelada remains.

And every day at the Guava, these qualities that make them unique compared to other primates are on full display. So once grooming ceases in the morning and the day is warming up, they make their way to the high plateau where they start feeding. Geladas form the largest groups you see in any primate—up to fifteen hundred individuals densely packed together. The reason that they can do this is that they specialize in grass; they're the only grass-eating primate. Because grass is everywhere, it's no problem to sit right next to your neighbor.

When Geladas eat grass, they pluck blade by blade. This might seem inefficient, but they do it with lightning speed, and they have really dexterous hands. Now, Geladas don't have any special digestive anatomy the way that, say, a cow does, that allows them to digest this energy-poor resource. Instead, for them, the secret is all in the teeth.

Now, if your finger is clean, you might wish to reach to the back of your mouth and rub your finger over one of your molars. You'll notice that it's quite flat. Okay, Geladas, on the other hand, have these huge, rugged molars with a lot of topography that act like scissors to cut through this really tough material. Our research at Wassa has shown that, of any primate, Geladas have the most efficient chewing mechanism, and that's how they survive on this really energy-poor resource.

But at Guava, with this ecologically intact habitat, Geladas eat more than grass: snails and lizards, roots and tubers, and the occasional pollen from the red-hot poker flower. So let's make our way from the herd to the individuals. As they move across the screen, they probably look like an amorphous mass, but in fact, there's some important substructuring to Geladas.

The basic social unit of Geladas is the one male unit. This consists of one male, like the guys you see there in the back, and between two and ten females; this is his harem. This male has sole mating access to all of these females. If females are closely related to each other—sisters, mothers, nieces, and aunts—and like any family, they fight a lot, and then they make up. We can also now return to this picture.

You probably surmise that those beads on the chest aren't actually millet seeds, but they're just beads. These are actually a complex signal that the Geladas are sending to the males, indicating they're ready to mate. The size and color of these beads track the menstrual cycle, so they become more red and bigger until the day of ovulation, and then they get smaller and paler, like you see here. In most baboons, this kind of sexual signal actually occurs on the buttocks, but because Geladas sit on their butts all day feeding, it's moved to a more visible place.