For the Love of Lemurs

To her delight, social worker-turned-scientist Patricia Wright has found the mischievous Madagascar primates to be astonishingly complex

A verreaux's sifaka lemur in Madagascar can leap 30 feet. Frans Lanting
Evolving an unusual appetite, golden bamboo lemurs devour young bamboo shoots, shunned by most animals because they contain cyanide. Lemurs' typical daily dose of the poison is enough to kill a human; no one knows how they manage it. Frans Lanting
A favorite of zoos, ring-tailed lemurs in the wild prefer the ground to treetops, making them easier to study. Frans Lanting

On a steep slope, hip deep in bamboo grass, in the heart of the Madagascar rain forest she saved, Patricia Wright is telling a story. “Mother Blue is probably the oldest animal in this forest,” she begins. “She was the queen of group one, and she shared her queendom with what I think was her mother.”

The animals she is describing are lemurs, primates like us. They are the unlikely product of one of nature’s reckless little experiments: all of them—more than 50 living lemur species—derive from a few individuals washed from the African mainland into the Indian Ocean more than 60 million years ago. The castaways had the good luck to land on Madagascar, an island the size of Texas 250 miles off the southeast coast of Africa. And there they have evolved in wild profusion.

Wright, a late-blooming primatologist from the State University of New York at Stony Brook, has made lemurs her life, tracking bamboo lemurs and sifaka lemurs that live in a handful of social groups in Ranomafana National Park. The story she is telling, to a work party from the volunteer group Earthwatch, is one episode in a running saga from 20 years of field research in Madagascar. If her tone evokes a children’s story, that may be apt. Wright is a matriarchal figure, with straight auburn hair framing a round face, slightly protuberant eyes under padded eyelids, and a quick, ragged grin. The business of conservation has made her adept at popularizing her lemurs, using all the familiar plotlines of wicked stepmothers, families broken up and reunited, love, sex and murder.

A female sifaka lemur perches on a branch over Wright’s head. The graceful creature, a little bigger than a house cat, has a delicate, foxlike snout and plush black fur with a white patch on her back. Her long limbs end in skeletal fingers, curved for gripping branches, with soft, leathery pads at the tips. She turns her head, her stark, staring, reddish orange eyes glowing like hot coals. Then she bounds away in a series of leaps, a dancer in perfect partnership with the trees.

Wright first visited the town of Ranomafana in 1986, basically because she needed a bath. She was looking for the greater bamboo lemur, a species no one had seen in decades. Ranomafana had hot springs—and also a rain forest that was largely intact, a rarity on an island where the vast majority of forest has been destroyed. In the steep hills outside town, Wright spotted a bamboo lemur and started to track it, the first step in getting skittish wild animals to tolerate human observers. “You have to follow them and follow them and follow them, and they’re very good at hiding,” she says. “It’s kind of fun to try to outwit an animal. When they decide that you’re boring, that’s when you’ve won.”

The lemur Wright followed turned out to be an entirely new species, the golden bamboo lemur, which even locals said they had not seen before. (Wright shares credit for the discovery with a German researcher working in the area at the same time.) On a return trip, she also found the greater bamboo lemur she’d originally been looking for.

As Wright was beginning a long-term study in Ranomafana of both the bamboo lemurs and the sifakas in 1986, she came face to face with a timber baron with a concession from Madagascar’s Department of Water and Forests to cut down the entire forest. Wright decided to try and preserve the lemurs’ habitat. She was married, raising a young daughter and employed at Duke University as a new faculty member. Friends warned that letting “this conservation stuff” distract her from research would hurt her career. “But I couldn’t have it on my conscience,” she says now, “that a species I had discovered went extinct because I was worried about getting my tenure.”

Over the next few years, she pestered the timber baron so relentlessly that he abandoned the area. She lobbied government officials to designate Ranomafana as the nation’s fourth national park, which they did in 1991, protecting 108,000 acres, an area five times the size of Manhattan. She also raised millions of dollars, much of it from the U.S. Agency for International Development, to fund the park. She oversaw the hiring of local villagers, construction of trails and training of staff. She sent out teams to build schools and to treat diseases such as elephantiasis and roundworm, which were epidemic around the park. Her work won her a MacArthur Foundation “genius” grant, and Stony Brook wooed her away from Duke with a job offer that allowed her to spend even more time in Madagascar.

Along the way, Wright found time to get to know her lemurs as individuals, particularly the sifakas in five territorial social groups, each of which had three to nine lemurs. Pale Male, in group two, for instance, “was a great animal, very perky,” she tells the volunteers. “He would play all the time with his sister, roughhouse around, go to the edges of the territory. And then one day, Pale Male disappeared. A lemur’s lost call is a mournful whistle, and his sister gave it all day long.” Pale Male had moved away to sifaka group three for an interlude of lemur bliss with the resident female, Sky Blue Yellow, producing a son named Purple Haze.

Lemurs typically sleep on the upper branches of trees. The fossa (pronounced “foosa”), a nocturnal mongoose, has a knack for finding them there. It creeps up a tree, its lean body pressed close to the bark, then leaps out and catches a lemur by the face or throat with its teeth. After a fossa struck one night, Sky Blue Yellow was gone. Pale Male, badly battered, soon also disappeared, leaving behind his 2-year-old son, Purple Haze. Six months passed by the time Pale Male came back bringing a new female into group three, and Wright was there to witness the reunion with Purple Haze. “That baby was so excited to see that father, and that father was so excited, and they just groomed and groomed and groomed.”

Ranomafana, it turned out, was home to more than a dozen lemur species, all with behaviors worth studying. Wright went on to build an independent research station there called Centre ValBio (short for a French phrase meaning “valuing biodiversity”), which now employs more than 80 people and accommodates up to 30 students and researchers.

A few prominent academics say privately that Wright has not produced enough solid science, or trained enough students from Madagascar as full-time scientists, given the funding she has received. (Wright points to more than 300 publications from research at Ranomafana.) Some conservationists complain that she steers initiatives to Ranomafana, sometimes at the expense of other parts of the island. “A lot of people are jealous of her,” says Conservation International president Russ Mittermeier, who gave Wright the grant that brought her to Ranomafana. “But, boy, give me 100 Pat Wrights and we could save a lot of primates.”

Wright was a Brooklyn social worker when her career as a primatologist got its start with a purchase she describes now as “almost a sin.” Before a Jimi Hendrix concert at the Fillmore East in Manhattan, Wright and her husband visited a nearby pet shop. A shipment had just arrived from South America, including a male owl monkey, says Wright, “and I guess I fell in love with that monkey.”

Selling wild-caught monkeys is illegal today. But this was 1968, and the monkey, which she named Herbie, took up residence in the apartment where the Wrights also kept a large iguana, a tokay gecko and a parrot. Monkey and parrot soon developed a mutual loathing. One night, the monkey “made a leap for the parrot, and by the time we got the lights on, he was poised with his mouth open about to bite the back of its neck.” The parrot was sent to live with a friend.

Wright began to read everything she could about Herbie’s genus, Aotus, nocturnal monkeys native to South and Central America. After a few years, she decided to find a mate for him. She took a leave of absence from her job and headed to South America for three months with her husband. Since no one wanted Herbie as a houseguest, he had to go too.

“I thought Herbie would be excited to see his own kind,” Wright says of the female she eventually located in a village on the Amazon. But he regarded the female with an enthusiasm otherwise reserved for the parrot. Wright ended up chasing the two of them around a room to corral them into separate cages. Later, this menagerie moved into a 25-cent-a-day room in Bogotá. “I think the truth is, it was 25 cents an hour because it was a bordello. They thought it was hilarious to have this couple with two monkeys.”

Back in New York, both Wright and the female owl monkey gave birth a few years later to daughters. Herbie turned into a doting father, returning his infant to its mother only for feeding. Wright stayed home with her own baby while her husband worked, and dreamed about someday discovering “what makes the world’s only nocturnal monkey tick.” Meanwhile, she sent off hapless letters—Brooklyn housewife yearns to become primatologist—to Dian Fossey, Jane Goodall and the National Geographic Society.

Eventually she discovered that Warren Kinzey, an anthropologist at the City University of New York, had done fieldwork on another South American monkey species. Wright prevailed on Kinzey to talk with her about how to study monkeys, and she took careful notes: “Leitz 7 x 35 binoculars, Halliburton case, waterproof field notebook...” Then she persuaded a philanthropist from her hometown of Avon, New York, to pay for a research trip to study Aotus monkeys in South America.

“Don’t go!” said Kinzey, when Wright phoned to say goodbye. An article had just arrived on his desk from a veteran biologist who had been unable to follow Aotus at night even with the help of radio collars. “You don’t have a radio collar,” said Kinzey. “I don’t think you should waste your money.”

But Wright was undaunted. She’d been spending summers at a family cottage on Cape Cod, following her two monkeys as they wandered at night through the local forest. “It was just fun to see the things they would do in the middle of the night. They loved cicadas, and there was a gypsy moth outbreak one year and they got fat. They saw flying squirrels.” So she told Kinzey, “I think I can do it without radio collars, and I’ve just bought a ticket, so I have to go.”

A few days later, she and her family climbed out of a bush plane in Puerto Bermudez, Peru, where her daughter Amanda, age 3, shrieked at the sight of a Campa tribesman with face paint and headdress. Wright said, “¿Donde está el hotel turista?” (“Where is the tourist hotel?”), and everybody within earshot laughed. The family moved in with some farmers before heading out into the field.

The local guides were nervous about going into the rain forest at night to help her hunt for owl monkeys. So Wright headed out alone, leaving behind a Hansel-and-Gretel trail of brightly colored flagging tape. She got lost anyway and began to panic at the thought of deadly fer-de-lance snakes and jaguars. “And then I heard this familiar sound, and it was an owl monkey. And I thought, OK, I can’t act like I’m scared to death. I’ll act like a primatologist. There are fruits dropping down in four places, so there are probably four monkeys. And I just started writing anything so I didn’t have to think.”

Near dawn, she heard animals stampeding toward her, and she scrambled up a tree for safety. “I heard this sound above me, and it was an owl monkey scolding and urinating and defecating and saying, ‘What are you doing in my territory?’ And by the time he finished this little speech, it was daylight. And then he went into this tree and his wife followed right behind him, and I thought, Oh, my god, that’s their sleep tree.”

She wrapped the tree with tape, “like a barber pole,” so she could find it again, and made her way to camp. Six months later, back in the United States, she presented Kinzey with her study and got it published in a leading primatology journal. She also applied to graduate school in anthropology. In her second week of studies at the City University of New York, Wright and her husband separated.

The mother of all lemurs—the castaway species that somehow found its way to Madagascar—was probably a small, squirrel-like primate akin to the modern-day bush baby in central Africa. Prosimians (a name literally meaning pre-monkey, now used as a catchall category for lemurs, lorises and bush babies) tend to have proportionally smaller brains than their cousins, the monkeys and apes, and they generally rely more on scent than vision. There are now ring-tailed lemurs, red-bellied lemurs, golden-crowned lemurs and black-and-white ruffed lemurs—so many different lemurs that Madagascar, with less than half a percent of the earth’s land surface, is home to about 15 percent of all primate species.

Among other oddities, the population includes lemurs that pollinate flowers, lemurs with incisors that grow continuously like a rodent’s, lemurs that hibernate—unlike any other primate—and lemurs in which only the females seem to hibernate. The smallest living primates are mouse lemurs, able to fit in the palm of a human hand. An extinct lemur as big as a gorilla roamed the island until about 350 years ago. Lemur species also display every possible social system, from polygyny (one male with multiple female partners) to polyandry (one female with multiple males) to monogamy.

Females are usually in charge. Males acknowledge the female’s dominance with subtle acts of deference. They wait till she finishes eating before going into a fruit tree. They step aside when she approaches. They cede her the best spot in the roosting tree at night.

Female dominance remains one of the great unsolved mysteries of lemur behavior. Food sources are scattered on Madagascar, and highly seasonal. It may be that females need to control the limited supply to meet the nutritional demands of pregnancy and lactation. Big, tough, high-maintenance males would likely consume too many calories, Wright theorizes, and provide too little compensatory protection against a flash-in-the-night predator like the fossa. But whatever the explanation, the lemur system of low-key female leadership has become a source of deep, playful empathy for Wright.

Dominant females don’t usually practice the sort of relentless aggression that occurs in male-dominated species such as baboons, macaques and chimpanzees, she says. They typically commit only about one aggressive act every other day, and “they do it expeditiously. They run up and bite or cuff the individual, and it’s very effective. They don’t do a lot of strutting around saying, ‘I’m the greatest.’” For every aggressive act, females engage in perhaps 50 bouts of friendly grooming, according to Wright’s observations. In fact, grooming is so important to lemurs that it has shaped the evolution of their teeth. Whereas our lower canines and incisors stand upright, for biting and tearing, theirs stick straight out and have evolved into a fine-toothed comb plate, for raking through one another’s hair.

Wright herself exerts dominance in the benign style of lemurs. “Zaka,” she says one afternoon, taking aside one of her best fieldworkers for a sort of verbal grooming. “I have to tell you about how important you are. When we were looking at all the data from the survey you did, it was very nice, very nice.” She is also a shrewd consensus builder, adept at winning local support. When she sends a student into the field, she urges him to hire local villagers as porters and guides, so they will see that the park can put money in their pockets. “I didn’t know how to make a national park,” Wright says. “What I did was brainstorm with the Malagasy [as people from Madagascar are known] here and with the people in the Department of Water and Forests. It was always a group effort. They had to be a part of it, or it wasn’t going to work at all.”

Given her sense of identification with female leadership among lemurs, Wright was shocked when she learned recently that her greater bamboo lemurs have a dark secret. “Listen to them!” Wright cries out one morning on Trail W, where her lemurs are violently shredding the bark from towering bamboo stems. “They talk all the time. They crack open bamboo all the time. How in the world could I have had such a hard time following them for so many years?”

Female greater bamboo lemurs spend much of their day chewing through the hard outer surface of giant bamboo stems, till the pieces of stripped bark hang down like broken sticks of dry spaghetti. What the lemurs want is the edible pith, which looks about as appetizing as rolled vinyl. It also contains stinging hairs and, in young shoots, a small jolt of cyanide. Having adapted to digest that poison lets the species exploit bamboo, an otherwise underutilized resource.

“The female is using her teeth to open these bamboo culms, really working—and the male isn’t there,” says Wright. “And all of a sudden you hear this big squabbling noise, and the male appears just as she opens up the bamboo, and he displaces her and takes it from her!” The thought leaves her aghast. “This is unheard of in Madagascar! Then he moves on and takes away the bamboo from the next female.”

At first, Wright and graduate student Chia Tan thought they were simply seeing bad behavior by one beastly male. Then a new male came in and did the same thing, forcing the researchers to contemplate the possibility that the greater bamboo lemur may be the only male-dominated lemur species. Wright and Tan theorize that the females cannot hear anything over the racket of their own chewing; they need the male to patrol the perimeter and alert them to danger. But they pay the price at feeding time. “It’s beautiful to watch,” says Wright, “it’s horrible to watch.”

In another corner of the park, sifaka group three is feeding in a rahiaka tree, and Wright is talking about Mother Blue, the lemur for whom she has always felt the deepest empathy. During the first decade of Wright’s work at Ranomafana, Mother Blue gave birth every other year, the normal pattern for sifakas. She raised two of her offspring to maturity, a good success rate for a lemur. Though female lemurs can live for more than 30 years, they produce relatively few offspring, most of which die young.

Mother Blue, says Wright, was not just a good mother but also a loving companion to her mate Old Red. “They groomed each other, they sat next to each other, they cared about each other.” But Old Red eventually disappeared, and in July 1996, says Wright, a new female arrived in group one. Lemurs are by and large peaceful, but they still display the usual primate fixations on rank and reproductive opportunity. Male interlopers sometimes kill infants to bring their mothers back into mating condition. Female newcomers may also kill babies, to drive a rival mother out of a territory. Soon after the new female appeared, Mother Blue’s newborn vanished. Then Mother Blue herself went into exile.

“I arrived a few months later and saw Mother Blue on the border between group one and group two, just sitting there looking depressed,” says Wright. “I thought, this is what happens to old females. They get taken over by young females and just die.”

Despite continuing deforestation elsewhere in Madagascar, satellite photographs indicate that Ranomafana remains intact. Partly because of the success there, Madagascar now has 18 national parks. President Marc Ravalomanana has pledged to triple the amount of open space under government protection by 2008. Wright, among her other ambitions, hopes to establish a wildlife corridor stretching 90 miles south from Ranomafana. She also still yearns to find out what makes different species tick.

At the rahiaka tree, for instance, Earthwatch volunteers are keeping track of the lemurs as they feed on a reddish fruit about the size of an acorn. The edible part, a rock-hard seed, is buried in a ball of gluey latex inside a tough, leathery husk. It doesn’t seem to discourage the lemurs. One of them hangs languidly off a branch, pulling fruit after fruit into its mouth, which is rimmed white with latex. The sound of seeds being crunched is audible on the ground, where Wright watches with evident satisfaction.

It turns out Wright was mistaken about Mother Blue. The old female lemur did not simply go into exile and die. Instead, she has moved into group three and taken up with Pale Male’s son, Purple Haze, a decidedly younger male. The two of them have a 3-year-old, also feeding in the tree, and a 1-year-old, roaming nearby. Wright is delighted with the way things have worked out. (She has also taken up with another male: her second husband, Jukka Jernvall, a Finnish biologist.)

Mother Blue, whom Wright says is probably 28 years old now, has worn teeth. The Earthwatchers are recording how much she eats and how many bites it takes her. They’re also supposed to collect scat samples containing broken seed remnants, to see how well she digests it. Someone squeamishly points out where droppings have just fallen in the thick grass. Wright wades in. She grabs a couple of fresh pellets with her bare hands and bags them for analysis back in the lab. Then she turns and leads her group uphill, deeper into the Ranomafana forest. “There is nothing more exciting than finding a new thing nobody knows,” says Wright. “You won’t believe it, but everything hasn’t already been discovered.”

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