Economic and Environmental Benefits of Biodiversity

Abstract

A ll ecosystems and human societies depend on a healthy and productive natural environment that contains diverse plant and animal species. The earth's biota is composed of an estimated 10 million species of plants, animals, and microbes (Pimm et al. 1995). In the United States, there are an estimated 750,000 species, of which small organisms, such as arthropods and microbes, make up 95%.1 Although approximately 60% of the world's food supply comes from rice, wheat, and corn (Wilson 1988), as many as 20,000 other plant species have been used by humans as food. Some plants and animals provide humans with essential medicines and other diverse, useful products. For instance, some plants and microbes help to degrade chemical pollutants and organic wastes and recycle nutrients throughout the ecosystem. The rapidly growing world population and increased human activity threaten many of these species. The current extinction rate of species ranges from approximately 1000 to 10,000 times higher than natural extinction rates (Kellert and Wilson