Research Communications

A Wild, Wild Life 

Primatologist Hogan Sherrow tracks the chimpanzee communities of Africa to uncover the secrets of humanity’s closest living relatives

Oct. 28, 2010

The male chimpanzees of Ngogo were out on patrol when they heard shouts.

A group of them charged toward the threat. At the crest of a hill, they met a party of males from the neighboring community.

The chimps attacked back and forth in waves, screaming and jumping, grabbing and biting at one another. Ngogo’s alpha male fought a big male from the other group; they wheeled around a tree before taking off in opposite directions. Other chimps rolled in balls of fists and teeth.

In the eye of the storm, Ohio University primatologist Hogan Sherrow scribbled observations as fast as he could into a notebook.

“I’m sure there was some serious adrenaline and testosterone going through my system,” he recalls. But he knew Ngogo chimps had never attacked a person, and he was less concerned with being injured than with recording the chimps’ behavior. “I was aware of the chimps, and the chimps seemed to be somewhat aware of me. There’s a comfort level you can reach where you feel you’re not in serious danger.”

Hogan Sherrow
Hogan Sherrow. Photo Credit: Kevin Riddell.

Sherrow has acquired that comfort during the 12 years he’s been conducting field research. Armed with a doctorate in anthropology from Yale University, he has observed everything from squirrels on the University of Oregon quad to Javan gibbons in Indonesia (thanks to a Fulbright scholarship) and cheetahs and baboons in Namibia.

For the last 10 years, he has focused on chimpanzees—just as he’s wanted to do since the ripe old age of eight, when he read about Jane Goodall in an issue of National Geographic.

When he isn’t teaching biological anthropology to undergraduates, Sherrow spends summers observing chimp communities, learning about humanity’s closest living relatives—as well as ourselves and our origins.

Sherrow has spent the bulk of his chimpanzee-observing career in Kibale National Park, a 300-square-mile preserve in southwestern Uganda that is home to 13 different species of primates. In addition to conducting research, he assists the Uganda Wildlife Authority with determining how best to protect the parks and reserves that contain the nation’s chimp communities.

Sherrow studied the Ngogo chimp community for his doctoral thesis, which included a focus on chimp adolescence. He found that chimps' teen years last longer than previously thought and that their adolescence length varies, as it does in humans.

That work “helps us think about variation,” says Sherrow. “We can’t paint all chimp communities with a single brush.”

Sherrow gathered further evidence of community variation when he observed the first case in Kibale of chimps using tools to forage for insects. The primatologists who’d been studying the Ngogo and Kanyawara communities for as many as 17 years had begun to suspect that the chimps didn’t use tools. Kibale doesn’t have many termite mounds that require devices for termite-fishing, and no one had spotted nut- cracking stones or ant-dipping sticks either.

One afternoon, Sherrow noticed a group of chimps chewing the ends of reed stems into fans, poking them into a log, and eating the insect parts they pulled out. They were using tools, just for a different act than the primatologists had expected.

“I was in the right place at the right time,” he says. “But that only happened because we had a habituated group that we could follow all the time.”

Habituating chimps—getting them used to having humans in their midst—is the most critical, and delicate, part of setting up a field site, says Sherrow.

Successfully habituating and observing chimps often involves 10- to 13-hour days in unrelenting heat with no chimp contact to show for it. But for Sherrow, the rewards are more than worth it.

“You have days when you’re spending 12 hours 15 feet away from them, and they completely ignore you,” he says. “They appear to not care that you’re right there, writing in your notebook and taking video. Those days are brilliant.”

Uganda Map
Map Illustration: Tina Ullman.

One of Sherrow’s research specialties is male aggression. Male chimpanzees are territorial and xenophobic, meaning they’re hostile toward chimps who don’t belong to their group. Fights can break out if members of different groups meet in the forest, and aggression can turn lethal.

Sherrow has provided evidence that such attacks, while not common, can have important consequences for populations. When he was following the Ngogo chimps, he witnessed the killing and eating of infants from neighboring communities. His observations supported the hypothesis that such killings are driven by territorial disputes—an idea that has since been supported by observations that chimp community borders can shift after years of intercommunity aggression.

In addition to revealing more about chimpanzee behavior, these findings impact the way we think about human behavior, evolution, and modern society, Sherrow says. Because chimps, humans, and bonobos have a common ancestry, comparing and contrasting our behavior helps define what makes us human.

“I think studying these things will deepen our understanding of why humans fight wars,” says Sherrow, adding that “it’s one more thing we share—fighting over territory. It’s not unique to humans and chimps, and I wouldn’t say the chimps are ‘going to war,’ but the patterns of behavior are similar.”

The same goes for mating habits and other behaviors we share with chimps, but not our more distant relatives.

“A lot of our behaviors are really basic,” he adds. “We don’t realize how simplistic they are until we look at animals.”

Another thing we share with chimps is what Sherrow calls “heavy reliance on learned behavior,” a combination of mentorship and practice makes perfect. Sherrow has seen younger Ngogo male chimps latch on to older ones as social role models, grooming them and learning critical behaviors such as how to hunt and integrate into the community.

It takes time for the youth of Ngogo to get it right, though.

When males patrol, they go out in single file along the edge of the community and look for other chimps or signs of previous activity. They walk in silence, acting anxious, pausing at ridge tops to listen for other chimps in the valleys.

When the young chimps go on their first few patrols, they vocalize and break sticks and generally make more of a racket than their seniors.

“Their skill level lags behind their participation,” says Sherrow. Or, to put it another way, “They screw up a lot.”

Courtesy of Hogan Sherrow.

Now, with funding from Ohio University and the National Geographic Society, Sherrow is working to set up a long- term research site in Kibale on a chimp community called Wantabu. It would be one of only about a dozen field sites for chimpanzee observation in the world.

“Not many people are setting up new field sites these days,” says Karen Strier, a professor of anthropology and affiliate professor of zoology at the University of Wisconsin-Madison. “It’s really great that he’s trying to do it. The more comparative information we have, the easier it is to put any one study in perspective.”

Sherrow also would like to establish a partnership for Ohio University with Makerere University in Kampala, Uganda, similar to those enjoyed by Harvard, Yale, and the University of Michigan.

In addition, the researcher is starting to develop collaborations with colleagues who study individual human cultures and subcultures, from the Hadza of East Africa to urban gangs and sports teams in the United States, with the intention of comparing human and chimp behavior on a larger scale.

“The point is to gather as much human behavior data as we can from a variety of groups and look for commonalities,” he says.

Facing global threats such as deforestation and bushmeat hunting, chimps— which number only 150,000 today—could disappear by 2060, taking with them a unique window into ourselves and our primate family.

Sherrow, who learned at an early age to respect the environment with the understanding that “if you’re not treating it well, you’re in trouble, too,” published a paper in December 2009 urging his colleagues to step up their efforts to educate people about conservation.

“Some people are doing amazing work,” he says. “But a lot of primatologists have a perspective that it’s not part of their job. We talk about conservation being important, but we could all do more.”

Sherrow puts his money where his mouth is. In Kibale, he hires local leaders as field assistants, talks to villagers—he had to start by dispelling rumors that his team was mining for gold—and brings schoolchildren into a forest they might otherwise only enter illegally to poach.

“It’s amazing what happens when you take the time to do that,” he says. Over the last decade, he has seen residents’ attitudes shift from discussions of where the best hunting sites are to how they can conserve the forest.

He doesn’t stop there, either. Together with his wife, Andria, Sherrow runs a nonprofit project called The Empower Campaign to help AIDS orphans and other vulnerable children near Kibale. Local women’s cooperatives make jewelry and handcrafts that Empower buys at fair trade prices. With the help of students at Ohio University and other U.S. universities, they sell the crafts to raise money for Ugandan schools.

Courtesy of Hogan Sherrow.

Sherrow’s own students benefit from his passion as well. Besides teaching courses in primate behavioral ecology and conservation (they’re paperless), he works hard to get his students research experience as undergraduates so they can directly observe the primates they’re learning about. He set up a partnership with the Columbus Zoo, and he’d like to take select students with him to Kibale in a few years.

“It’s very important for anyone studying primatology to get out in the field,” says senior Morgan Chaney, an advisee of Sherrow’s who studied play behavior in gorillas at the Columbus Zoo and plans to become a field primatologist.

Chaney isn’t the only one to catch Sherrow’s infectious enthusiasm. His classes frequently have waiting lists and attract students from across campus.

That might have to do with his teaching style, such as demonstrating primate calls in class. Says Chaney, “Here’s Dr. Sherrow standing in an ocean of 100 kids, saying, ‘This is a howler monkey, and this is a gorilla, and this is a gibbon.’ And you’re sitting there thinking, ‘I can’t believe this is happening right now.’

While Sherrow cherishes his students, he also wants to reach larger audiences. He appeared in an episode of “MonsterQuest” on the History Channel, searching for escaped chimps in the Everglades, and he continues to pursue television opportunities to talk about the importance of conservation.

Leon Anderson, the chair of the Department of Sociology and Anthropology at Ohio University, notes that Sherrow was able to “really provide a knowledgeable scientist’s view of the situation that countered some of the myths out there” during his appearance on “MonsterQuest,” a show that uses professional scientists to debunk urban legends.

“Viewers are not getting the same thing students get from my lectures, but if they walk away with a better understanding of evolutionary theory or what climate change is doing to the environment right now, a little about where we fit in the animal world, or why we are a primate, I call that a success,” Sherrow says.

Sherrow figures that if nothing else, he owes it to the public to share what he learns, as he estimates that taxpayers fund 80 percent of his research. But he also enjoys it—the outreach, the teaching, even the grueling days in the forest.

As he puts it: “Every day is a good day to be a primatologist.”

By Stephanie Dutchen

This article appears in the Autumn/Winter 2010 issue of Perspectives magazine.