EXPEDITIONS – MEDICINAL PLANTS : That is responsible for the thousands of different chemicals found in tropical forest plant some 25% of all drugs found in a modern pharmacy in fact are derived or copied from those found in the rainforest. The reason for this is quite simple. Unlike animals, plants are unable to run away from predators Instead, over millions of years they have evolved a bewildering variety of what are called “secondary compounds chemicals that have nothing to do with the plant’s physiology but rather have evolved solely for the purpose of defense. The alkaloid from which cocaine is derived is one of them. Curare (a common blow-dart poison), quinine, rotenone and a host of hallucinogenic drugs are among the thousands of others. Although masked in what appears to be a uniform green, the jungle is actually a staging ground for an intense chemical battle that daily rages between animals and plants. Because a single hectare (2.5 acres) of rainforest can have up to nearly 300 different species of trees (a typical temperate forest may have 20), in reality the jungle represents the largest, most highly-sophisticated repository of biologically active chemicals in the world.
EXPEDITIONS – MEDICINAL PLANTS : Despite the potential utility such a reservoir holds for drugs, medicines and other uses ironically less than 1 % of the Amazon’s plants have thus far been chemically analyzed. Most scientists agree that it would be prohibitively expensive and would take hundreds of years to randomly search for useful compounds in the rest. Scientists called ethno botanists, however a cross between an anthropologist and a botanist are currently trying to take advantage of the fact that there are already people who know just where many of those compounds are. Having lived in intimate contact with rainforest plants for thousands of years, the Amazon’s Indians, and especially their medicine men, or shamans, have a vast, unwritten botanical knowledge that is passed on orally from generation to generation. As one ethno botanist working in Peru phrased it: “Looking for a useful plant on your own is like entering a huge, multi-million-volume library and trying to find a certain paragraph at random. The Indian shaman is the librarian of the jungle: he can show you a hundred different medicines at the drop of a hat.”Since native cultures are disappearing even faster than the intact rainforests which surround them, however, ethno botanists are currently hurrying to record the Indians’ legacy of millennia, before it, too, disappears.