Introduction:
In Their Habitat
When Jane Goodall first headed to the Gombe Stream Chimpanzee Reserve at the behest of the archaeologist Louis Leakey, it was July 1960 and the country was called Tanganyika. It took four months of watching chimpanzees through binoculars before Goodall finally managed to win their trust enough that a male with a gray beard let her observe him at close range.
National Geographic three years later introduced the world to Goodall and the chimps she named David Greybeard, Mrs. Maggs, Count Dracula, Huxley, and Goliath. She was not the first person to study chimpanzees in the wild. But with her patient constitution and the help of bananas, she was the first person from whom wild chimpanzees did not run, allowing her to document in detail their daily lives, social structure, tool use, hunting, and emotions.1 Like an explorer who makes first contact with a remote tribe, Goodall penetrated a community, complete with its own culture, that until then had been known only to its own members.
Nearly half a century has passed since Goodall made her initial visit to what is now the Gombe Stream National Park in Tanzania, and the catalog of sites conducting long-term studies of wild chimpanzees by 2010 included Mahale Mountains National Park in Tanzania, Kibale National Park and Budongo Forest Reserve in Uganda, the Taï National Park in Côte d'Ivoire, Bossou in Guinea, Fongoli in Senegal, and the Goualougo Triangle in the Republic of Congo's Nouabalé-Ndoki National Park. The many other researchers who "habituated" wild chimpanzee communities also needed much patience, especially since the field now looks askance at making chimps feel comfortable with the presence of humans by provisioning bananas and other foods, which Goodall and others later recognized disrupted the animals' natural behavior. So while it is not easy to gain the trust of wild chimpanzees and to observe them at close range for extended periods—habituation took five years in Taï—clearly, humans have figured out how to do it.2
In 2006, I set out to observe the world of chimpanzee research at close range, and that, too, required that I slowly build the trust of individuals in a foreign community. It was hardly the first contact between a journalist and primate researchers—which in part explained why my many phone calls and e-mails for a time went unanswered. I also did not want to simply interview people for a few minutes on the phone. I wanted to see the scientists doing what they do in their natural environments, from the rainforests of Africa to the laboratories, zoos, and sanctuaries where captive chimpanzees live in many countries. That added another obstacle: great apes are endangered, which means that few exist, and even fewer humans devote their lives to studying them. Apes also live in places where entry is tightly restricted, and it can be just as difficult to receive permission to visit a protected national forest to see a wild chimp community as it is to be invited to a biomedical research facility to see a captive one. So I had to be patient with my requests.
From the outset, I understood that many in the community had received too much media interest for their own tastes. They did not exactly run and hide away in the trees when they saw a journalist coming, but they knew both the benefits and the perils of publicity, and they preciously guarded their time—and access to the animals they studied. It made good sense. Goodall is arguably the world's most famous living scientist, and many of those who have followed in her footsteps—including the ethologist Frans de Waal, the evolutionary biologist Richard Wrangham, and the psychologist Roger Fouts—have written popular books and magazine articles themselves and been featured prominently in an endless stream of documentaries. Dian Fossey, who studied gorillas in Rwanda also at the behest of Leakey, became the subject of a Hollywood blockbuster, Gorillas in the Mist. Biruté Galdikas, the "orangutan lady" and the third of "Leakey's Angels," has garnered two appearances on the cover of National Geographic, written four books, and had several books written about her. In his native Switzerland and elsewhere in Europe, the chimp researcher Christophe Boesch has a high profile, and the same is true of the primatologists Tetsuro Matsuzawa, Toshisada Nishida, and Kinji Imanishi in their native Japan.
In time, most every request I made was granted, and people graciously invited me to watch them hike through rainforests, conduct biomedical and cognitive experiments with live animals, examine bones and brains from dead ones, and even collect and then study chimp sperm under a microscope. My travels took me to Uganda, Japan, Germany, England, Russia, and all over the United States. Only one place I wanted to visit ultimately froze me out: National Geographic actually blocked a trip I had planned to the Republic of Congo to observe researchers studying chimpanzees and gorillas in the remote Goualougo Triangle; the husband-and-wife team of scientists working there had welcomed me, but then were forced to rescind their invitation because the magazine funded them and wanted to monopolize their research for a story. I mention this not to complain, but to illustrate the peculiar inner workings of the community, as well as to explain the great satisfaction I felt each time I managed to finally visit researchers at their work sites. They had, in a sense, become habituated to my presence. At the very least, they tolerated my watching them do their business, and more often than not, I was greeted with enthusiasm and a genuine eagerness to help me understand and communicate what I was seeing.
Unlike many authors of books about chimpanzees, I am not a researcher or even connected to one. That means I do not emphasize my own original findings, I have no agenda, and I, too, struggle to cut through the scientific jargon to distill the significance of specific studies. My aim from the start was simply to explore anew a question that tickles at the human mind, and which with the publication of the chimpanzee genome in 2005 was pushing answers into novel directions: What are the dividing lines between humans and chimpanzees, between us and them?
In 1925, the psychologist Robert Yerkes teased open many minds with his book Almost Human, which argued that humans and chimpanzees had so many similarities that much could be learned if we studied them more carefully. Almost Human had another agenda that from today's vantage seems unnecessary and downright absurd: to convince people not to revile chimpanzees. "There is intense and well-nigh universal curiosity about these animals, but it is often coupled with strong dislike or repulsion," he wrote. "Perhaps as our ignorance disappears we shall lose also the prejudice and unreasonable dislike which makes many feel that genetic relationship with the monkeys or apes is belittling."3 The fact that chimpanzees were seen by some at the time as "inventions of the devil," as Yerkes noted, could be traced to creationism: Almost Human appeared the same year as Scopes v. the State of Tennessee, which famously put the teaching of Darwinian evolution on trial. Yerkes was doing his bit to combat the creationists of his day, and the mounting evidence for the chimp's humanlike appearance, behavior, and biology made a strong case for the Darwinians, one that continues to resonate.
Goodall, fifty years later, pushed this "almost human" viewpoint to forward an entirely separate agenda. As a leading advocate for protecting the habitats of wild chimps and a foe of researchers who housed chimps in small cages and conducted invasive biomedical experimentation, she believed that a critical mass of humans would most likely come to her cause if they imagined their own hands reaching for the curl of a chimpanzee's finger. Goodall was pursuing noble and worthwhile goals, and indeed she, along with Yerkes and other pioneering chimpanzee researchers, deserves much credit for making people more aware of the intelligence, social needs, and emotional depth of our closest cousins. But I think the need to emphasize our similarities has abated.
With the flood of genetic information now available from many species, the argument for Darwinian evolution no longer requires the chimpanzee-human connection as its linchpin. Advocates also have made much headway in persuading humans to treat chimpanzees more humanely, with invasive research steadily becoming less common, housing for captive chimps improving, and more people recognizing the plight that wild chimpanzees face because of our disregard for their well-being. And there is something fundamentally backward about the "almost human" rubric for chimps. From everything I can tell, no chimpanzee looks at a human and wonders, Is that where I came from? Nor do chimps ponder the possibility that we represent where they are heading. Yet humans from every culture look at chimpanzees and see hints of their more primitive selves.
"Almost human" inherently pushes people to look for similarities. Yet, while we have a lot of chimpanzee in us, we cannot hope to see that clearly unless we can identify the specific features and forces that separate us from them. We have bigger and more complex brains, full-fledged language and writing, sophisticated tools, the control of fire, cultures that become increasingly complex, permanent structures in which to live and work, and the ability to walk upright and travel far and wide. It also is important to recognize that we are not "better" in every regard. No human stands a chance against an adult chimpanzee in a fight or a tree-climbing contest; many diseases that devastate us spare them; and one study even suggests that they have much better short-term memory.
I am not arguing that we should treat chimpanzees with any less respect, that the case for evolution is any less compelling, or that we should conduct studies of humans to better understand chimpanzees. "Almost human" and "almost chimpanzee" represent two sides of the same coin. But people have many misunderstandings about our relationship to chimpanzees, and I am convinced that we have focused too much attention on the heads rather than the tails.
H. A. Rey's children's classic, Curious George, opens with an illustration of George swinging on a vine and eating a banana. "This is George," the text reads. "He lived in Africa. He was a good little monkey and always very curious."
George, as the drawing clearly shows, is a chimpanzee, not a monkey.
This fundamental mistake riles people who study chimpanzees, and with good reason. In evolutionary time, monkeys and apes diverged from each other about 25 million years ago. Humans and chimpanzees split from a common ancestor at most 7 million years ago. So to understand the difference between humans and chimpanzees, as a starting point, it is critical to recognize that monkeys are not apes.
How do we know George is not a monkey? He does not have a tail. All monkeys, save for the misnamed Barbary ape and the Sulawesi black ape (which look nothing like George), have tails. In contrast, no ape—a family that includes chimpanzees, humans, gorillas, bonobos, orangutans, gibbons, and siamangs—has a tail.
The differences between apes and monkeys reach far beyond the tail. But the fact that many people don't know that simple distinction—and that a popular children's book has corrupted young minds since 1941—underscores the confusion about where to draw the dividing lines that separate humans from other species.
As I tour the world of chimpanzees, I do not address every dividing line between us and them, nor do I become chummy with the likes of David Greybeard, the extraordinarily communicative Washoe and Kanzi, or any other knuckle-walking ape. But I introduce many chimpanzees, as well as other apes, including bonobos and orangutans, focusing on the differences that matter. I begin at the most microscopic of differences, looking into the blood, then slowly zooming out for the successively broader, and more encompassing, vantages of the brain and finally the body. I mesh little-known historical tales with the most cutting-edge science to explain the origins of chimpanzee research and reveal where the field is heading. And while few primatologists study both captive and wild chimpanzees, I blend findings from both areas, which often complement or challenge each other in surprising ways.
George, the chimpanzee, is defined by his curiosity. Humans are an extraordinarily curious species, too. But the range of our curiosities and how we satisfy them are distinct, and since the dawn of our consciousness, since the first myth of our origins was passed on, we have explored that particular difference and pondered what, exactly, it means to be human. Chimpanzees are a unique—and rapidly closing—window into our answer.
