How do you calculate the number of chimpanzees living in the forests of Nigeria? If you’re National Geographic Explorer Rachel Ashegbofe, you listen carefully. After discovering that Nigerian chimpanzees are a genetically distinct population, Rachel began searching for their nests to study them more closely. Now she’s teaching her community how to be good neighbors to humans’ closest genetic relative—and potentially save them from extinction.
(Sounds of walking through the forest)
RACHEL ASHEGBOFE (PROJECT DIRECTOR, SW/NIGER DELTA FOREST PROJECT): So it's just two of us. And then there was the marijuana growers who had like automatic weapons with them. And we stumbled upon them in the forest. And they saw us too.
AMY BRIGGS (HOST): This is the hot, humid forest of southwestern Nigeria. It’s a tropical jungle teeming with life: There are these 50-foot trees stretching for sunlight, scaly pangolins (sort of imagine a possum trying very hard to be a pine cone), and elusive chimpanzees.
Rachel Ashegebofe, a Nigerian chimpanzee researcher, was out with a team member looking for signs of chimpanzees when she found herself face-to-face with a drug cartel.
RACHEL ASHEGBOFE: They were like, who are you? Where are you coming from? Where are you going to, you know? And they had their guns flashing right in front of us.
BRIGGS: Rachel was in trouble. Marijuana is illegal in Nigeria and so is farming in protected forests. Rachel is the project director for a forest conservation group and sometimes comes to uproot farms like this one. But usually she’s prepared with motorcycles, guns, and lots of backup. But if these men knew who she really was, they might not let her and her colleague leave.
ASHEGBOFE: They were armed and we are not. We couldn't challenge them. So I used the other weapon, which is natural to me, or to any woman. So I played in that female card like, Oh, just a woman researcher student who is going into the forest looking for monkeys. Have you seen any monkeys lately? So, yeah, that was my strategy to avoid being killed.
BRIGGS: The strategy paid off.
ASHEGBOFE: For a typical Nigerian—an average Nigerian man—it's unthinkable that a woman—an educated woman—would go into the forest. So, of course, in his mind, he's thinking, Yeah, she must be right, that she's just a student because it doesn't make any sense that a woman is doing what I am doing.
BRIGGS: But under all that pressure, in the back of her mind Rachel was already thinking of coming back to reclaim this small patch of forest.
ASHEGBOFE: Right there, my GPS is on. It's taking record of that particular position. And then we use the GPS coordinates from that particular location to trace them back later—this time around to get them arrested and destroy their farms and their campsite.
BRIGGS: This forest that Rachel watches over is one of the last strongholds of a unique group of chimpanzees that could become extinct in just a few years.
I’m Amy Briggs, executive editor of National Geographic History magazine, and you’re listening to Overheard, a show where we eavesdrop on the wild conversations we have here at Nat Geo and follow them to the edges of our big, weird, beautiful world.
This week, we meet a trio of women dedicated to learning all we can about Africa’s chimpanzees.
It’s been 60 years since Jane Goodall did her pioneering research, and since then, new generations of conservationists are stepping up to protect Africa’s most endangered chimps today.
More after this.
BRIGGS: I’d like to play you a little clip from a National Geographic documentary released way back—well, not that way back for some of us—in 1984: Among the Wild Chimpanzees.
Documentary voice-over: For centuries there were fearsome tales of a half-human monster roaming the African forests. Even in modern times, knowledge of the elusive creature—the wild chimpanzee—was largely based on speculation. Then, in 1960 a daring young Englishwoman set out to sort fiction from truth.
BRIGGS: It’s probably not too hard to guess whom this documentary is about.
Voice-over: Her name? Jane Goodall. She was 26 years old and destined to make scientific history.
BRIGGS: Jane Goodall had been hired to go on this expedition in what is now Tanzania by an anthropologist named Louis Leakey.
He thought observing great apes could help us understand how ancient humans lived.
Especially chimpanzees, because they are so similar to humans—they are tied with bonobos as our closest living genetic relatives.
Jane spent months watching the chimpanzees and slowly introducing them to her presence.
JANE GOODALL (film clip): I discovered not far from camp that there was a peak overlooking two valleys. And from this vantage point I was able to gradually piece together the daily behavior of the chimps.
BRIGGS: And eventually she was able to watch them close up and pioneered the study of chimpanzees in their natural habitat.
GOODALL: The chimps very gradually came to realize that I was not dangerous after all. I shall never forget the day after about 18 months, when for the first time a small group allowed me to approach and be near them. Finally I had been accepted. I think it was one of the proudest and most exciting moments of my whole life.
BRIGGS: Jane Goodall made all kinds of incredible discoveries about chimpanzees:
Like they make tools to hunt termites. And kind of like birds, they build complicated nests to sleep high in the trees. And they seemed to have their own set of chimp etiquette and could be kind or cruel to each other.
Jane stayed at that spot, now Gombe Stream National Park, in Tanzania. She was there for decades, and set the groundwork for chimpanzee research to this day.
Jane Goodall’s research started in Central Africa. But there are other groups of chimpanzees who live all across the continent—some have been isolated from each other for hundreds of thousands of years. Studying those apes would fall to more recent generations of primatologists.
BRIGGS: So what was it like for you when you first saw a chimpanzee in the wild?
KATY GONDER (BIOLOGY PROFESSOR, DREXEL UNIVERSITY): Well, so that's a very good story. Actually, it's a story I get made fun of a lot for, but I'll tell you anyway...
GONDER: ….what happened.
BRIGGS: This is Katy Gonder, head of the biology department at Drexel University. She started studying chimpanzees in the ‘90s.
GONDER: When I first went to Nigeria, chimpanzees were believed to be extinct in Nigeria.
BRIGGS: Jane Goodall wrote in her 1986 book The Chimpanzees of Gombe that apes were extinct in Nigeria. And that’s what most Western biologists believed at the time.
GONDER: I didn't even believe that there were still chimpanzees. And my Ph.D. adviser, John Oates, was like, no, no, no, they're still there. Go and look. So we tracked them for three days and we found them. And it was such a powerful experience.
BRIGGS: People in Nigeria knew the chimps were there and how to find them.
GONDER: So I was with this gentleman named Salamu, who knew everything about animals. And I was in my first year of graduate school. And I told Salamu—I said, Look, Salamu, I'm a professional primatologist. I will go up to them and get a picture. You stay back here.
BRIGGS: It was a big moment for Katy, on the cusp of taking a picture of an animal that was supposed to be extinct.
GONDER: So I snuck up on these chimpanzees. I had my camera in my pouch and everything. So I snuck up and snuck up. It's like, I don't know, 45 minutes or an hour. I finally got right up underneath them, and I was like, this is it! And I took my Velcro thing and I went WHEECK and I went in and grabbed my camera. And all of a sudden chimpanzees were like, WHO-WHO. And they started throwing stuff at me. And so all I have is this picture of my eye and blurry vegetation as I saw them. And Salamu? He laughed and laughed and laughed. But it was such a powerful experience. It really was. I mean, there's just nothing like seeing wild apes. But for many years after that, every time I would go back to Gashaka-Gumti, Salamu would say, Ah, here comes the professional primatologist. So yeah, I ate a little bit of humble pie for many years after that.
BRIGGS: Despite the humble pie, Katy continued to go back and gathered more evidence: Pictures, fur, and fecal samples.
Katy was able to extract DNA to compare these chimpanzees with other known groups of chimps.
GONDER: When we did that, what we found was that they were very, very different from any other chimpanzees around.
BRIGGS: So in 1997, Katie proposed that this group of chimpanzees be considered its own subspecies.
Now a subspecies is kind of what it sounds like. Different, but not different enough to be its own separate species.
Take, for instance, Siberian tigers in Russia and Sumatran tigers in Indonesia. They’re both still tigers, but evolving in these two different places gives them different traits—from visible things like size and coat to differences at the genetic level.
Same principles apply for chimps. For example, the chimpanzee subspecies Katy observed doesn’t seem vulnerable to the simian version of HIV, like the chimps of Central and East Africa.
Before Katy wrote her paper, the local people already had a sense that there were different kinds of chimpanzee living in the area.
GONDER: They said this all the time. They said, you know, there's two different kinds of chimpanzees here. And for years I was like, oh yeah, right. There's two different things everybody just talks about. But, in fact, now we have all this camera trap data. So they like literally were really telling the truth. But they were saying, well, there's ones that are light brown and ones that are really dark, and that's what they meant.
BRIGGS: Subspecies also develop different technologies based on where they live. Each chimp group passes down different generational knowledge to their kids, like how to use tools to hunt for food and crack open nuts found in the region.
If a subspecies goes extinct, so does all of their particular chimpanzee culture and biology.
Katy says that extinction could deeply impact all the other living things in the forest that depend on the chimps.
GONDER: Usually when those animals are lost, it's a sign that the ecosystems are not healthy anymore, and they play a really important role in the forest, like chimpanzee poop is very important, not just for my genetic studies but also really important for—chimpanzees eat fruits and then they disperse seeds, and they're you know, they're basically the farmers of the forest. And that's really quite an important role.
BRIGGS: There are four known subspecies of chimps. The one that Katy observed is now known as the Nigeria-Cameroon chimpanzee.It is the rarest subspecies.
And one of the places their numbers are threatened the most is in western Nigeria, where only a few small pockets of them survive.
BRIGGS: Do you think that there's hope for the survival of chimps in western Nigeria?
GONDER: I do, but, you know, it will require constant surveillance in order for them to survive. There are very, very, very few of them left. I know firsthand how hard it is to find them. Several years ago, I went into a place called Ise Forest in Nigeria, and we found the Nigeria-Cameroon chimpanzee.
BRIGGS: Katy went to western Nigeria to find DNA samples. She spent six months looking without seeing a single chimpanzee.
So she hired a group of hunters to help track them—and together they spotted a group of chimps at the edge of a destroyed marijuana farm.
GONDER: And I thought, my goodness, I have found them, but I probably just sentenced them to death. Now these hunters know where they are. And so I just made the decision to never go look for them again. It just wasn't worth it.
BRIGGS: Ise forest is where Rachel Ashegbofe works.
BRIGGS: So how long do you think this particular group of chimps would last without conservation, without these efforts?
ASHEGBOFE: We estimated no more than five years. Like we even think five years is an overestimate.
BRIGGS: Rachel grew up in Nigeria. Her first jobs were in forest conservation.
But when she found out about the small pockets of chimpanzees in danger of extinction, she felt like she had to help them.
ASHEGBOFE: I really—was really concerned that if I didn't step in or intervene, we could as well say goodbye to this population of chimpanzees surviving in southwest Nigeria and the Niger Delta.
BRIGGS: Rachel has been studying the chimpanzees in southwestern Nigeria for about eight years. She estimates that there are only about 25 chimps living in her protected area.
And they’re not easy to observe.
ASHEGBOFE: So chimpanzees in this part of the country where I'm working are very, very shy, as in very wary of humans.
BRIGGS: One reason Jane Goodall was able to learn so much about chimpanzees was that she spent years slowly showing a few of them that she and her team weren't dangerous.
But in Ise, chimpanzees have learned that humans are dangerous. And because the chimps keep their distance, Rachel and her colleagues almost actually never see them. So instead, she studies them by listening.
ASHEGBOFE: When chimpanzees are excited, they really find it hard to hold it in. So, yes, they'll make that kind of sound (imitates chimpanzee sound). You know, they would scream loud, like this is festival. This is a feast.
BRIGGS: And she studies them by getting her hands dirty. By collecting their poop.
BRIGGS: So this might be a little gross. How do you know if the poop comes from a chimpanzee?
ASHEGBOFE: I mean, it's a very interesting question. And I'm going to tell you this story because it's quite—it's so funny how this happened. So this was a few years ago, and at that time, chimp poop—collecting chimp poop—was so important because one of the objectives of the work we're doing at the time was to determine their genetic linkage. So I was so desperate to get chimp poop.
BRIGGS: Rachel explained how she and a small group had spent a week in the forest searching for a poop sample without success, until the very last day of their trip. They woke up at 5 a.m., hoping to hear a chimp call and track it to its nest and… treasure.
ASHEGBOFE: We heard the sound, and I was so happy. And I was like, this is it. Today we're going to get chimp poop.
BRIGGS: They had a good idea of what direction the nests were in, but finding them wasn’t easy.
ASHEGBOFE: We didn't see a single nest. I got so depressed. We just walked forward a bit. And then I stopped and I was like, I smell something, stop here. I smell something. And we started to search the ground everywhere there. And voilà! We saw chimp poop. And, you know, how did I know it was chimp poop? Number one, instincts. Number two, they smell almost like human poop.
BRIGGS: I'm so glad you offered that up. I didn't want to ask.
ASHEGBOFE: It smells really bad, but guess what? I just didn't care. Like I was just happy seeing them. At that point I was just so happy to see poop.
BRIGGS: Like Katy Gonder, Rachel is also looking for genetic samples to show that this group is unique. Maybe even unique enough to be considered its own subspecies, separate from the chimps Katy observed in other parts of Nigeria.
ASHEGBOFE: So the southwestern chimps have been isolated for a very long time—to such an extent that they have built a type of genetic pool that is significantly unique. So the probability that there could be a subspecies is very likely than it is unlikely.
BRIGGS: Declaring a new subspecies can lead to more funding and resources to protect the chimps in Ise Forest.
In 2018 Rachel teamed up with genetic researchers at the Copenhagen Zoo, and presented a study showing that this group is genetically different from the rest of the subspecies.
ASHEGBOFE: And that has brought us to where we are now, where we discovered that the chimpanzees in southwestern Nigeria, although they are closely related to the Nigeria-Cameroon chimpanzee, but they are really quite unique group.
BRIGGS: Whether or not these chimpanzees could be their own subspecies is still up for debate. To find the answer Rachel needs more data. And that means more poop.
It took 10 years for the Nigeria-Cameroon subspecies to be widely accepted. But the chimps in western Nigeria might not have that much time. Nigeria as a whole will be up against some pretty big hurdles for conservation in the next few decades.
ASHEGBOFE: By 2050 the UN estimates that Nigeria will have the third largest human population in the entire world, after China and India.
BRIGGS: Nigeria’s growing population needs work and food; so new farms and towns are driving rapid deforestation there.
ASHEGBOFE: I don't know if you get the picture. It's that bad, like you worked in an area that used to be forests. You observed, say, for example, elephants in that area or you had chimps in that area. And then go back the following year and found that place is no more forests. It's people living there now, like a township— like a rural township is now in place of where used to be forests, where elephants used to walk.
BRIGGS: A big part of Rachel’s job is convincing the local community that the forest is worth saving in the first place.
BRIGGS: And it sounds like so much of your work, too, is in, you know, working with that other group of great apes, you know, Homo sapiens, human beings.
BRIGGS: What is their role in conservation? What are their reactions?
ASHEGBOFE: It’s been a lot of work. In the beginning, they were very, very opposed to any conservation—any suggestions for conservation—because really you can't blame them. The forest is where many of them get their livelihood from. But many of them are beginning to see that conserving this forest is equivalent to conserving our lives as well.
BRIGGS: Part of this work is finding new jobs for people who used to work as hunters or loggers—and giving them a role in protecting the forest and the chimps who live there.
(Ranger trainees chanting)
BRIGGS: This is a group of new ranger trainees hired by Rachel. They’re heading out on their first mission to shut down an illegal farm.
ASHEGBOFE: So this is the season when they do cultivate marijuana. So we've got our hands full.
BRIGGS: The trainees are able to quietly arrest the farmers. They tie them together around the waist with a long rope, like beads on a string.
Then they destroy the crops and burn the campsite.
ASHEGBOFE: We took them to the community. And when the community saw that we arrested these people, you know, their attitude towards us did like a 360. You guys are great, you guys are fantastic, wow! Now we see the reason for this conservation area. We are working together. We are here for them not just for chimpanzees, but we are here for them as well. And we are partners with them, not against them, as they initially thought.
BRIGGS: Chimp conservation has a long tradition of hands-on work. Jane Goodall did it. Katy Gonder does it. And now Rachel is doing it too—and bringing more people in the community to the party.
Each woman has had to face the unique challenges of their own time and place, adapting their approaches in the face of new threats to chimpanzees.
Rachel still has a long way to go before Ise and its chimpanzees are secure. It isn’t clear whether the forest will survive in the long term. But at least now it has a fighting chance.
There’s a lot of truly fascinating information about chimpanzees that we couldn’t include in this episode—there just wasn’t room. But we’ve put together a few links for the curious explorer in our show notes.
Like the research that is still going on today at Gombe Stream National Park into the social lives of chimpanzee mothers.
Or read about how chimpanzees were declared endangered by the U.S. Fish and Wildlife Service in 2015, making biomedical research on them illegal. Now hundreds of those chimpanzees live in sanctuaries across the U.S.
And subscribers can dive into the National Geographic online archive to see the many articles written by Jane Goodall.
That’s all in the show notes. You can find them there in your podcast app.
And while you’re there, be sure to rate and review us in Apple Podcasts. It really helps other listeners find us.
Overheard at National Geographic is produced by Brian Gutierrez, Jacob Pinter, Laura Sim, and Ilana Strauss.
Our senior editor is Eli Chen.
Our Senior Producer is Carla Wills.
Our executive producer of audio is Davar Ardalan.
Our fact-checkers are Robin Palmer and Julie Beer.
Our copy editor is Amy Kolczak.
Hansdale Hsu sound-designed this episode and composed our theme music.
This podcast is a production of National Geographic Partners.
The National Geographic Society, committed to illuminating and protecting the wonder of our world, funds the work of National Geographic Explorer Rachel Ashegbofe.
Whitney Johnson is the director of visuals and immersive experiences.
Susan Goldberg is National Geographic’s editorial director.
And I’m your host, Amy Briggs. Thanks for listening, and see you all next time.
Did you know that chimpanzees hunt tortoises? Catch up on all there is to know about Pan Troglodytes through National Geographic’s chimpanzee fact sheet.
Chimpanzee moms form strong bonds with their children. Take a look at some of the latest research on the social lives of chimpanzee mothers.
And for subscribers:
Travel back in time to Jane Goodall’s original 1963 article for National Geographic, just three years after she started her field research at Gombe Stream National Park.
Or take a look at the entire National Geographic Magazine Archive.
Learn more about Rachel Ashegbofe’s work through the website for the South West/Niger Delta Forest Project.
Jane Goodall continues to be a conservation icon and she even has a podcast of her own called The Jane Goodall Hopecast. You can listen to the first episode here.
For Disney+ subscribers, you can also watch National Geographic’s 2017 documentary film Jane, which features rare footage of her chimpanzee work, and 2020 film The Hope, which focuses on her career as an environmental activist.
If you like what you hear and want to support more content like this, please consider a National Geographic subscription. Go to natgeo.com/explore to subscribe today.
The National Geographic Society is committed to illuminating and protecting the wonder of our world. Learn more about the Society’s support of its Explorers.