Based on the article by Jon Bowermaster [1]
Ever since man came busting out of the last Ice Age 11,000 years ago, armed with sharpened sticks, traps, and snares, he has had a nasty habit of wreaking havocon plants and animals.
Occasionally the annihilationwas unintentional, as when predators were introduced by early explorers to remote localessuch as the dodo on the island of Mauritius. More often, man was merely making room for one thing: himself. The first time he swept across North America, man wiped out saber-tooth cats, mastodons, mammoths, huge ground sloths, short-faced bears, and dire wolves. Centuries later, when the British colonists came ashore in South Carolina, they found, according to one account, "endless Numbers of Panthers, Tigers, Wolves, and other Beasts of Prey." Needless to say, the newcomers wasted little time in wasting them, too. The winning of the West that followed included the butcheringof the buffalo, along with varieties of grizzly bears, wolves, foxes, and cougars.
By the late nineteenth century, with the advent of industrial technology and modern farming, man's weapons of choice in his continuing war against nature had become more sophisticated. Today parking lots, pesticides, waste dumps, and industrial pollutants of all stripes are the new spears, though the victims remain the same plants, animals, and their homes. Grasslands and wetlands are increasingly replaced by subdivisions and malls. Trees and lakes are poisoned by acid rain. Tropical forests are slashedand burned at the rate of 100 acres a minute. As population density soars from South America to Southeast Asia, economic mightcontinues to overrule ecologic right. Since 1900, Africa's wildlife population has declined by more than seventy percent as the human population has grown six-fold.
The number of wildlife extinctions and endangered species is mind-boggling.In the early twentieth century, the earth was losing one species a year; today, it's one species a day400 times the natural rate. By comparison, it's estimated that dinosaur species died offat a rate of one every 1,000 years. By the middle of the next century, according to the Nature Conservancy, one-half of all the earth's present species may be lost, largely as a result of man's greed, cruelty, and vanity.
In the United States alone, there are 565 animals on the U.S. Fish and Wildlife Service's list of endangered species; outside the U.S., the projected figure is 508. Calculating the number of endangered plants and invertebrates is difficult. On one hectareof any rain forest live countlessspecies of plants and insects that exist nowhere else; if that hectare of hardwood is razed whether to make cardboard packing boxes for VCRs or disposable chopsticksthe species are gone forever. Some estimates of endangered plants and invertebrates run as high as 40,000.
One school of biological theorists contends that extinction is evolutionary, arguing that we all have to go sometime. But there's a big difference between natural and unnatural death. Already the Tasmanian wolf, the laughing owls of New Zealand, the Caribbean monk seals, and many more are history. And while there are some efforts underway to rescue a handful of speciesin the U.S., for example, a number of zoos have had success breeding and bringing back such species as condors, ferrets, and Siberian tigersthey represent a drop in the bucket,particularly at a time when only thirty Spanish lynxes and thirty Western swamp tortoises remain, and when entire species of insects are vacatedevery day. While much of the public handwringing over (and Hollywood fund-raisers on behalf of) endangered species is done in the name of the "glamour" animalslike blue whales and bald eagles (which are actually staging a comeback of sorts, after a twenty-year, $35 million campaign)the unparalleled horror of today's carnage lies more in the sheer number of plants that are disappearing.
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When the dinosaurs were killed off 65 million years ago, flowering plants survived. Today dozens are being eradicatedweekly, many before they can even be named or studied. The tragedy in their extinction is that many hold potential cures for everything from cancer to AIDS. Thirty-five percent of the pharmaceuticalsin use in America today contain ingredients originally derived from wild plants. The Madagascar periwinkle, for example, is a key ingredient in curing lymphatic leukemia, the South American ipecac is used to treat amoebic dysentery; hormone medicines like cortisone and diosgenin (the active ingredient in birth control pills) were developed from wild yams; the heart medicine strophanthin comes from a wild West African vine.
But aren't there plenty of shrubsand vines to go around? Who's going to miss an odd thousand or so of the 30 million different kinds of insects that crawl the face of the earth? Certainly evolution will continue even as we pave and pollute the planet. Unfortunately, as man's technology weeds outthe survivors in the plant and animal world, those that will thriveare hardly the most biologically diverse, or necessarily the most beneficial. Cockroaches, rats, raccoons, bats, and weeds are far from endangered.
What is wrong with the current rate of extinction is its chillingacceleration. According to the World Wildlife Fund, thousands of existing species may be extinct by the end of this century. Such extreme dying-off portendsthe disruption of widespread, complex habitats, key players in the planet's ecological balance. With more and more of those players missing in action, such essentials as clean air and water, productive soil, and many harvestableproducts will increasingly be things of the past. And extinction only breeds more, and faster, extinction.
One especially frightening aspect of the endangerment to wild plants and animals is not what we know for a certainty will happen but what we cannot predict. Our knowledge of earth's biological fabric and its mysteries is, at best, incomplete, uneven. Thus the consequence of man's continued alteration of nature's diversity cannot be forecast with any real degree of accuracy. It is the unknown that has even the experts scared stiff.
