The Rain Forest: A Close Up Look
Boston Museum of Science Magazine, October 1990
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The science writer Timothy Ferris and I were bouncing ideas off one another over the phone the other day, as we do from time to time, when he spun out a new argument for saving the rainforest, based on information theory. “Wouldn’t it be great if the Brazilians could somehow be persuaded to skip the industrial age, with all its population and toxic side effects,” Ferris mused, “and go right into the informatic age? If they could only be made to realize that they are sitting on a gold mine in the Amazon rainforest -a gold mine of information far more valuable than the current uses it’s being put to, like pasturizing one cow for every two acres of cleared woodland. Think of all the money the people who invented Word Perfect have made. More than a million people are using the word-processing program. And what is Word Perfect? It’s just data, maybe half a megabyte of information. And when you think that there is perhaps a terabyte of information in a single plant, you see what I’m driving at?”
“So what you’re saying is that the EI Dorado Europeans have been looking for in the Amazon ever since they first blundered into the valley actually exists, ” I said.
Ferris didn’t have to convince me, because I’d been fascinated with ethnobotany (the study of how people use plants) for more than 20 years, since I was an undergraduate at Harvard and got to know some of the graduate students of the remarkable professor Richard Evans Schultes. Schultes had been collecting plants, particularly hallucinogenic species, from the Indians in the Amazon since the forties.
I come from a family of naturalists, and my older brother Nick, who ran a nature museum for Westchester County, had independently become interested in the plants used by the Delaware Indians, who had once lived there. A few years out of college, I became the resident naturalist at the Marsh Sanctuary, a small gem of a wildlife preserve in Mount Kisco, and I invited Timothy Plowman, one of Schultes’ students to make a botanical inventory of the place. We spent the day wading in the marsh, roaming in the woods, zipping from habitat to habitat. Plowman’s energy was incredible, and it was clear that he knew every plant in the place, including its family and its Latin name. It was one of the most stimulating days of my life. My rudimentary knowledge of the local flora had been mainly acquired from poring over field guides, and it was as if Plowman lifted a veil from my eyes.
I also invited another of Schultes’ students, Homer V. Pinkley, to give a talk about his ethnobotanical work with the Kofan Indians of Ecuador. Pinkley had catalogued their entire material culture. I asked him about something that had been puzzling me: How was it that some of the uncontacted tribes deep in the Amazon have banana plantations (you can see them from the air), when bananas come from Asia and were first introduced in the New World by Spanish conquistadores on the island of Hispaniola. Pinkley said, “because plants travel faster than man,” and as a perfect demonstration of this he gave me seed from one of the plants the Kofan use that he had brought back. The Kofan and I have yet to meet each other.
It didn’t take me much longer to get to the Amazon myself. In the fall of 1976, as part of an eight-month research for Sierra Club Books, J spent a month in the remote, only recently contacted, Kayapo Indian village of Mekranoti. I took walks in the forest with one of the men who healed the sick people in the village with forest plants. He showed me a plant that he said the women used as a contraceptive. All they had to do was drink a brew of its leaves, he claimed, and they wouldn’t get pregnant for two years. The fact that the women kept nursing their babies until they were over two may also have helped keep them from getting pregnant. I gave a specimen of the plant, with the rest of my ethnobotanical inventory from Mekranoti, to the National Institute for Amazonian Research, in Manaus. A botanist there told me that it was in the chemically active spurge family, so it could perfectly well have contaceptive properties, but to date, as far as I know, the plant has not been analyzed.
According to Dr. Michael Balick, the director of the Institute of Economic Botany at the New York Botanical Garden, about 260,000 species of higher plants (not counting ferns, mushrooms, and other nonflowering plants) have been described on the planet and “if I had to hazard a guess I’d say maybe another five or ten percent are still unidentified. Two-thirds of these plants are in rainforests, and there are around 90,000 species in the neotropics, and maybe twothirds of these 90,000 are in the Amazon.
“But of the 260,000 species worldwide,” he went on, “the biochemical or medicinal properties of fewer than one percent have been exhaustively studied. And yet from that one percent alone a quarter of all the prescription medicine sold at pharmacies in the United Stated is derived.”
I thought of the famous miracle drugs from the Amazon. Curare, the muscle relaxant vital in modern surgery, was developed from an arrow poison made from the plant Strychnos toxifera which the Indians of several tribes in the Upper Amazon dipped their blowgun darts into. Quinine -for centuries, until the advent of sulfa drugs, the only treatment for malaria -was developed from the bark of the cinchona tree. Indians in the Northeast of Brazil bring into town bundles of leaves of jaborani trees, which they have harvested with machetes; and Vegetex, a subsidiary of Merck, processes pilocarpine, used in the treatment of glaucoma, from them. It’s a $25-million-a-year business.
“You don’t have to be a genius to recognize that in the other 99 percent of the world’s known flora that hasn’t been analyzed, there may be something extremely valuable,” Dr. Balick went on.
You mean something like the cure for cancer or AIDS? I asked.
Why not? Dr. Balick said, except that he suggested that in the case of AIDS, therapy might be a better word. In fact he was working with the National Cancer Institute’s screening program on just that. “The U.S. Government has undertaken a multi-milliondollar effort to screen tropical plants for anticancer and -AIDS properties, which is a very good sign that the therapeutic potential of the rainforest flora is being taken seriously.
“And given that two-thirds of plant species are in the rainforests, and that half of the forests, according to one estimate, will be gone by the year 2000, it’s very clear we’re in a race against time.”
The Indians, who have been using the plants in their neck of the woods for generations and chances are have already discovered the important ones, provide an invaluable shortcut in the quest. (By the way, even chimpanzees, with whom we Homo sapiens share 98 percent of our genes, have recently been found to treat themselves with leaves that have antibiotic and helminthic [antiworm] properties). The Chacabo Indians were found to use 82 percent of the species in a sample hectare of rainforest, 95 percent of the 619 individual trees. Another tribe, the Tirio, has 300 plants in its forest pharmacopoeia. Seventy percent of the 3000 plants identified by the National Cancer Institute are rainforest species, Catherine Caulfield reports in her book, In the Rain Forest. Other rainforest plants are used to treat Iymphotic leukemia, Hodgkins disease, and amoebic dysentery.
Developing a marketable rainforest drug is an expensive proposition. First the compound has to be isolated, then toxicological tests to evaluate possible side effects must be conducted, and clinical tests to determine whether the product really works and how effective it is compared with other products already on the market. It can take years to satisfy all the rigorous guidelines of the Food and Drug Administration. And of course there is the question of securing a stable supply. But even if the Mekranoti’s contraceptive turns out not to be viable, I wouldn’t trade my walks in the rainforest with Indian healers or what I learned from their closeness to nature about my own humanity -for anything.