Milwaukee holds a key to the survival of the bonobo, our evolutionary cousins.
by Erik Ness
Milwaukee Magazine, March 1996
Awakened from a nap, Kitty is disoriented, her world askew.
She unfurls her long, graceful fingers, blindly rummaging through unfamiliar space. Only the day before, she had been in Atlanta, her home for seven years; she now sat on a loft in a small room in a Milwaukee basement. The flight, like too many that go through Chicago, had been hell. She missed an early plane, then missed her bedtime. In the morning, she had eaten, carefully explored her new home—fingering every surface as the blind will do—and gone back to sleep. Now she groped for a rope and swung gently over to the cage door, her gentle bonobo face pressed against the wide mesh. Her lips pursed in a greeting kiss.
“Good morning, girl,” coos Barb Bell. Kitty’s eyes look unfocused, but they are hardly vacant. She lets her working senses size up her visitors. “These animals don’t do well in quarantine,” explains Bell, the bonobo keeper at the Milwaukee County Zoo. She showers soft-talk on the fragile Kitty, gently stroking her fingers where they grip the bars.
Across the hall, also in quarantine, Kitty’s traveling companion, Linda, was awake, peering curiously at us. Her cage was adjacent to the main holding pen, and she had spent part of the night chattering with the resident group: Maringa, 24, the matriarch and queen bee; Lody, 23, the elder male; their offspring, Lomako, 11, and Eliya, 5; Laura (Linda’s daughter), 26; Laura’s son, Murph, 5, and eight-month-old daughter, Yatole. The gregarious bonobo often crosses paths with other groups in its wild home in Zaire. It’s more of an event in zoos, and Linda hadn’t seen her daughter in two years. The excited outcome was a good round of screeching and hooting all around.
Bonobos are profoundly social beings. Their close cousins, the chimpanzees, also are very social, but their culture is aggressive, male-dominated, sometimes even war-like. Bonobos live within a peaceable matriarchy, and the females do not reign with the same degree of force as do male chimpanzees. Sexual contact, not aggression, is used to diffuse tension. Other than humans, they are perhaps the only mammals known to have sex for non-reproductive purposes. Some even call them promiscuous.
Also called pygmy chimpanzees, bonobos are only about 15 percent smaller than chimpanzees, but they are considerably more elegant. They have longer legs, narrower chests, smaller ears, a darker face and hair parted neatly down the middle. Though they can walk upright with greater ease, they are generally more arboreal than chimps. Bonobos are also highly endangered, and the County Zoo is part of an international effort to halt the species’ death spiral. More than one-tenth of all captive bonobos now live in Milwaukee, twice as many as last year. Kidogo, 21, and Makanza, not quite 2, also came from Atlanta, and another was born here. The only other U.S. zoos with bonobos are those in San Diego, Columbus, Cincinnati and Fort Worth.
With only about 100 bonobos in captivity worldwide, zoos must be careful to avoid inbreeding. Kitty and Linda had been in Atlanta as part of a nationwide cooperative breeding program coordinated by Gay Reinartz, conservation coordinator for the Milwaukee Zoological Society. Kitty, 45, had never given birth, and researchers wanted to find out why Linda, 40, has produced more young—11—than any other captive female.
Now they were coming home for their twilight years, but because of this routine quarantine, it would still be at least 30 days before they could touch another bonobo. Laura would get a TV for stimulation, but that wouldn’t do much for Kitty, who is mostly deaf and has inoperable detached retinas in both eyes. She was going to have to tough out the quarantine in the quiet darkness, with encouragement from the zoo staff. No doubt she was lonely and a little scared, but it had been a far easier journey than her first, when she was ripped violently from the far-flung rain forest of central Africa.
On July 25, 1995, Laura had her second child, Yatole, and Linda became a grandmother. Yatole is a reminder of better times for the bonobo. Long ago, legend says, a courageous young woman named Miesi went walking to visit her fields. It was a time of war, and on the forest path, she was surrounded by enemy warriors. Miesi was afraid, but cautioned her captors that her husband was right behind her with a band of hunters. “Run away, before he catches up!” she warned.
Unbelieving, the enemy set about to kill Miesi, when suddenly a cry rose from the forest and the trees began to shake. A troop of bonobos sprang screaming from the brush, attacking with branches. Bonobos are three times as strong as humans and very smart, so the warriors dropped their weapons and ran. To this day, Miesi’s rescue is honored by her descendants, who will not eat bonobos. They call bonobos yatole.
The Mongandu people share that taboo, believing that bonobos once lived as their brothers. And according to evolutionary biologists, Mongandu legend is not complete fiction. Bonobos, along with the rest of the great apes, share 98 percent of our genes. Five to 7 million years ago, bonobos, chimpanzees and humans all diverged from a common ancestor. While the harsh savanna environment is thought to have spurred human evolution, the bonobos’ forest home has changed relatively little in that time. If bonobos also have changed comparatively little, they may closely resemble our ancestral species.
Indeed, if you see a bonobo walking upright, you might think you’re in a National Geographic special on human evolution. When they stand, bonobos closely resemble an artist’s conception of Australopithecus, the prehominid nicknamed Lucy by anthropologists. “That’s what we always say about Laura,” says Bell. “She’s Lucy.”
Perennial favorites at the zoo, apes are a fun-house mirror of evolution. “People love looking at the similar behaviors, the similarities in appearance, the things that they wish they could do publicly that the bonobos get away with,” explains Reinartz. “We can’t scratch our behinds and pick our noses in public, and they’re doing it.”
And the sex? For bonobos, sex is a stress reliever and replacement for aggression. For example, when Laura was brought into the group a few years ago, she rubbed genitals with Maringa, the matriarch, then the males put on a little show. “Everybody copulated, and then they sat down and ate,” remembers Bell. “With gorillas, we all sit there with fire extinguishers and hoses and you expect some bumps and bruises and gashes and blood. With the bonobos, it was like: ‘Hi, I love you; where’s breakfast?’”
Bonobos are among the rare animals that copulate face to face, and the coupling is not exclusively heterosexual, either. Females form strong pair bonds, in part by genital rubbing. The males also will rub behinds, or “penis fence” as they hang from trees. This may sound X -rated, but keep in mind that the average encounter lasts only 13 seconds. Sex is important, but it’s not an obsession. During an average zoo visit, you’re not likely to feel like a voyeur.
As crowd-pleasing as earthy behavior is, nothing draws interest quite like mother and child. When Yatole was born, Laura often retreated high on a platform at the back of their cage. There she lolled about, cradling her infant on her stomach away from prying eyes. Soon she became less shy, though no less protective.
When her daughter was about six weeks, Laura treated a gathering crowd to a captivating maternal display. As Yatole suckled, her eyes darted about, her delicate face contorting expressively. When she finished, Laura cradled her daughter in her lap, wobbling her head deliberately in what the keepers call a happy head. You could almost hear Laura say “kootchy-kootchy-koo,” and she grinned wildly whenever Yatole responded with her own happy head. Curious Murph wandered over, bent his head down and kissed his little sister. Eliya approached more tentatively, but Yatole reached her slender hands back and just barely touched Eliya perhaps for the first time.
Through the glass partition, less than a yard away from this domestic bliss, the crowd was entranced. Dozens of people—mostly women—pressed close, crowding in for a first look at the newborn. The thick glass was meant as a barrier, but across it flowed the same raw maternal energy nurturing Yatole on the other side.
Stand behind that glass long enough, and you can see the whole family affair. It’s easy to tell bonobos apart from one another, and once you learn their names, you can quickly begin to identify their personality traits. There’s Maringa, the groomer—she plucks herself and the others nearly bald. Five-year-old Eliya is curled up beside her for an afternoon nap, which will last until Murph, who is the same age, decides he wants to play and grabs her bedding away. Murph escapes to the ropes, but Eliya is the champion acrobat and she badgers him mercilessly. Eleven-year-old Lomako, meanwhile, is running and pushing a milk crate across the floor in a young stud’s display of bravado, while Lody, the elder male, joins the ruckus by charging crosswise at Lomako and dragging a tangle of vines. It looks random, but they do it again and again, with choreographed precision. Then they all stop to eat. All things considered, they seem like a pretty functional family.
They’re also watching us. Once I was seen in the company of their keepers, they recognized me afterward. When their old keepers stopped by for a visit after many years, the bonobos spotted them among the crowd of zoo visitors and went bonkers.
The kinship of apes and humans seems obvious here, but pushing that notion beyond mere romantic fancy was a small-scale scientific revolution orchestrated by pioneering anthropologist Dr. Louis Leakey. For decades, Leakey and his wife, Mary, scoured Tanzania’s Olduvai Gorge for fossilized human ancestors. Their skeletons didn’t reveal behavior, but Leakey guessed that observing great apes would, and he recruited a trio of young women to do this work: Jane Goodall, for chimpanzees; Dian Fossey, for gorillas; and Birute Galdikas, for orangutans, though Leakey once suggested she study bonobos instead.
Goodall, the first close observer of primates in the wild, enthralled the world with her discoveries: primitive toolmaking, cooperative hunting, even rudimentary warfare. Leakey proudly proclaimed that anthropologists would have to either redefine humans or accept chimpanzees as a member of the family.
But what if Goodall had ventured into Zaire instead of Tanzania? Handed a different mirror, would we have seen different things in ourselves and reached a different evolutionary understanding of who we are?
In a provocative Scientific American article, former University of Wisconsin-Madison primatologist Frans B.M. de Waal speculates: “Just imagine that we had never heard of chimpanzees or baboons and had known bonobos first. We would at present most likely believe that early hominids lived in female-centered societies, in which sex served important social functions and in which warfare was rare or absent.”
Goodall wrote that chimps lived in “the shadow of man,” but the shadow falls both ways.
The Zaire River cleaves a wide, muddy arc across half of Africa, splitting its country and continent in two. North of the river, from Tanzania to West Africa, live chimpanzees. South of the river lies one of the last crumbling citadels of big wilderness—a huge swath of tropical forest with few human inhabitants. Here live the elusive bonobos, confused with chimpanzees until the early part of this century, when an anatomist poring over old bones in a musty Belgian museum realized the skull before him was not a juvenile chimpanzee, as labeled, but a different species altogether.
Science is just beginning to study the bonobo in new, remote research stations that take weeks to reach. But there is little time to spare. In the last two decades, the bonobo population, under pressure from hunting and logging, has dropped by half.
Before 1976, the principal threat to the survival of bonobos and other primates was the pet and zoo trade. At the time, pet monkeys were sold by mail order, and zoos commonly mounted collecting safaris. Because full-grown wild apes are immensely strong and not easily handled, it was easiest to catch infants. But a bonobo mother, like all apes, will die trying to protect her child from hunters; many did and still do.
Kitty, Linda, Maringa and Lody were all caught in the wild. While no one knows for certain, life in captivity must have begun something like this: Forest hunters killed their mothers, then captured the distraught infants. The mothers were eaten by hunters or sold as bushmeat; the young were put in crude cages and carried to the nearest river. Traveling by boat to Kisangani or the capital, Kinshasa, the infants were either sold at market or directly to animal dealers. For each that survived, many others died from the trauma of losing their mothers and traveling.
The cruelty and devastation of the pet and zoo trade led to the Convention on International Trade in Endangered Species, adopted in 1976. Under the treaty, endangered species cannot be traded without permission from the governments of both origin and destination. With the official wild trade effectively shut down, zoos began to focus on captive breeding programs.
Enter Gay Reinartz. As an undergraduate, she had studied inbreeding in lemurs, and when she moved to Milwaukee with her husband, she visited the zoo hoping to continue her work in conservation genetics. Milwaukee had been almost too successful in breeding highly endangered snow leopards and Siberian tigers. Because there were so many descendants from the Milwaukee cats, other zoos wanted to return 17 of them because they were not eligible to breed.
Reinartz helped untangle the cat crisis, and her role grew as genetics became more important in zoo acquisitions. One day, she found an advertisement for a group of gorillas and a set of bonobos being sold by a zoo in the Netherlands. Intrigued, her research discovered that there were very few bonobos in the United States. “Very shortly, there would have been no alternative to breed bonobos in this country without having very serious degrees of inbreeding,” she says. Reinartz knew that Milwaukee Zoological Society President Dr. Gil Boese wanted to expand the ape collection, and now she had a scientific purpose as well. In 1986, the society purchased the animals for the zoo at a cost of about $600,000, and by December, they were in Milwaukee.
Strategically breeding endangered species marks the evolution of zoos from sedentary circuses to scientific and environmental institutions. In 1988, Reinartz became the coordinator for the bonobo species survival plan, a breeding program under the auspices of the American Zoo and Aquarium Association. Inbreeding is a problem for small populations, whether they are zoo-bound or wild. Survival plans were supposed to keep the zoo gene pool as wide as possible; eventually, their genes might pass back into the wild. Captive populations would also serve as ambassadors, while cooperation between zoos and researchers would further conservation efforts. But as Reinartz learned more about the bonobo, she became increasingly concerned about the wild population in Zaire.
That population is estimated to be between 10,000 and 20,000. All of the great apes are endangered, but because bonobos live only in Zaire, they are hostage to the political vagaries of a single dictator. Zaire is among the most corrupt of African nations, and its rapidly expanding population is young and restless for material gain. Though Zaire has set aside vast reserves, they are poorly protected and none of them includes a habitat for bonobos. Several years ago, 30 percent of the bonobo range was slated for logging, and more is likely to fall. “But the roads put down for loggers don’t just carry chain saws,” says Reinartz. “They carry hunters, farmers and disease.”
Bonobos would not survive by the effort of zoos alone, she realized.
In 1987, the Milwaukee Zoological Society brought Louis Leakey’s son, Richard, also an anthropologist, to town. The younger Leakey posed a simple question: If Australopithecus still lived, would it, too, be housed in the zoo? Reinartz remembers everybody’s face going blank, and the question still haunts her.
Among primatologists, it is neither an academic question nor knee-jerk animal-rights activism. In Milwaukee, keepers are training bonobos to cooperate with basic veterinary procedures, allowing better care of the animals without the trauma of tranquilizers. Using simple rewards of bananas and juice, Bell taught Laura to cooperate with ultrasound during her pregnancy and to tolerate a breast pump. Bell estimates that the Milwaukee bonobos know more than 100 words and can understand them linked in simple sentences.
The training in Milwaukee is designed to help the animals cope with their artificial environment—high intelligence is an observed fact, not a research goal. But chimpanzees in captivity continue to astound language and behavioral researchers. Tutored chimps can master hundreds of signs, and one chimp, with no human training, learned dozens of signs from his companions. One captive bonobo merited an entire book: Kanzi: The Ape at the Brink of the Human Mind. There is even a movement, the Great Ape Project, to endow apes with the basic civil rights of life, liberty and freedom from torture.
Should bonobos be in zoos? “We’re talking about ethical questions that are post facto,” says Reinartz. “We already have them in zoos. Whether it was a good decision to put them here, I don’t know. If Australopithecus were endangered and in zoos, then we should get the most from them that we possibly can. Our duty—whatever the species—is not to let them languish.”
Some are concerned that captive breeding will preserve only a pale remnant of a species in the zoo setting. Siberian tigers, for example, breed successfully in Milwaukee, but most field conservationists consider them doomed in the wild. Habitat loss is too severe, conservation efforts are meager, and no one knows how much of their behavior is learned and thus irrevocably lost. Chimps breed so well in captivity that there is no room in zoos for offspring, and the females are all on Norplant. Yet a recent reintroduction effort failed when the released chimp could not socialize with its wild brethren.
Geza Teleki, former director of the now defunct Committee for the Conservation and Care of Chimpanzees, is critical of zoos’ focus on captive breeding. “That’s a collector’s mentality that has nothing to do with the preservation of an animal where the vast majority of the population lives in the wild,” he argues. “That’s how you approach a stamp collection, not ecological preservation.”
Teleki believes that zoos could better serve conservation by helping with the health and maintenance of captive animals in places like Zaire. Unfortunately, he says, it’s not happening. “The problem is, zoos in developed countries—primarily Europe and North America—perceive these countries as wasted effort,” says Teleki. “That’s beside the point. Having exploited those species for several hundred years, zoos now have an obligation to try to help local people, who are tryjng to do their best under declining circumstances. They are not doing that.”
To a point, Reinartz agrees: Zoos must reach beyond their exhibits if the bonobo and other endangered species are to survive. She has heard complaints about the cost of the Milwaukee County Zoo’s new Apes of Africa Pavilion, and recognizes a ring of truth. “Two million dollars could go a long way in Zaire. You can’t argue with that. But where is it going? I could have a check for a million dollars for conservation, but who am I going to make it out to? What infrastructure exists for conservation? Just to start throwing money at something is no solution.”
Meanwhile, the bonobo species survival plan is beginning to forge links with field conservation. It has funded research in the wild, and is helping to produce a notebook for school children in Zaire about the bonobo and its cultural and biological importance. Another project sells bonobo T-shirts in the United States, using the profits to send more shirts to Africa. Everyone wears T-shirts in Zaire, and hopefully they, like the notebooks, will raise awareness and make conservation easier in the long run.
But a question remains unanswered: Should bonobos be in captivity? Reinartz is hesitant. “If I had to answer that, my automatic answer would be no. No, uh-uh, they shouldn’t. But if you asked about a toad, I’d pretty much say the same thing. I don’t believe that an animal has more rights to exist over another simply because it is more or less like man.”
Planet Earth may lose 20 percent of its plant and animal species in the next few decades, and many scientists believe that this loss of biodiversity is our gravest ecological crisis. Watching young Yatole cavort in Milwaukee with her family, it is hard to hear the chain saws in Zaire, and harder still to stop them. But the destiny of her species rests now in the hands of the people and politicians of Zaire, the logging companies and, to a small degree, the people of Milwaukee.
Birute Galdikas, the orangutan specialist, wrote in her recent biography that “[a]s we watch the great apes slip toward extinction, we are witnessing our own future on an increasingly inhospitable planet. If we take action to save our nearest relatives and their tropical habitats, we are taking the first step in saving ourselves.”
Wisconsin’s own Aldo Leopold helped invent the science of ecological restoration at Madison’s University Arboretum. “The last word in ignorance,” he believed, “is the man who says of an animal or plant, ‘What good is it?’ If the land mechanism as a whole is good, then every part is good, whether we understand it or not. If the biota, in the course of aeons, has built something we like but do not understand, then who but a fool would discard seemingly useless parts? To keep every cog and wheel is the first precaution of intelligent tinkering.”
“Like animals, we as a species are not bound by countries,” says Reinartz. “We think we are, but we’re not, and we’re certainly not isolated. I know that we have our own human needs here. But we also have a tremendous amount of world authority, capability, and wealth and influence. We need to take more of an interest in the larger world. If animals have to be our peace ambassadors, well so be it. The wealth of this planet, in terms of biodiversity, lies outside our boundaries, and if the health of the planet depends on what those countries do, we better get with it and try to be part of the solution.”