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Encyclopedia of Global Resources part 39

Encyclopedia of Global Resources part 39 provides a wide variety of perspectives on both traditional and more recent views of Earth's resources. It serves as a bridge connecting the domains of resource exploitation, environmentalism, geology, and biology, and it explains their interrelationships in terms that students and other nonspecialists can understand. The articles in this set are extremely diverse, with articles covering soil, fisheries, forests, aluminum, the Industrial Revolution, the U.S. Department of the Interior, the hydrologic cycle, glass, and placer mineral deposits. . | 350 Endangered species Global Resources purposes when new diseases pests and weather conditions cause serious reductions of those plants upon which human health and life depend. An example of such a seed bank in the United States is the National Plant Germplasm System in Colorado under the aegis of the Department of Agriculture. Endangered Species and Medicine Throughout their histor y on Earth human beings have used nature as a kind of pharmacopoeia utilizing plant and animal products to alleviate sickness and cure various diseases. For example the bark of a willow tree was the source of a substance that reduced fever and pain this substance later resulted in the commercial drug aspirin . Even though researchers especially those active during and since the chemical revolution of the eighteenth century have developed a growing number of artificial drugs that have proved increasingly effective in treating certain infectious and degenerative diseases modern medicine continues to depend on plants and animals to provide substances that treat and even cure diseases directly or that ser ve as precursors to creating drugs that can treat or cure a variety of human ills. In the late twentieth and early twenty-first centuries some scientists estimated that one-fourth to one-half of all medicines prescribed by doctors derive in some way from natural sources. For example more than three million Americans who suffer from heart disease rely on digitalis a drug derived from the purple foxglove plant. Even recent drugs often have their source in nature. Between 1998 and 2002 more than 70 percent of small-molecule drugs licensed by the U.S. Food and Drug Administration could be traced to natural sources. According to the World Health Organization many people in developing countries depend on natural remedies for more than three-quarters of their medical needs. While many of the plant and animal species The proboscis monkey whose name is taken from its prominent nose is an .