ABSTRACT
Variety is both the spice of life and basis of its survival. The importance of biological diversity to human society is hard to overstate. An estimated 40 percent of the global economy is based on biological products and processes. Poor people, especially those living in areas of low agricultural productivity, depend heavily on the genetic diversity of the environment. Forests protect the watersheds, moderates climate and act as the foster mother of agriculture. They hold the key to global food and water security. Darwin’s hypothesis of natural selection and survival of the fittest will have no operational validity if our planet is not so rich in biological diversity; this provided opportunities for the domestication of plants and animals leading to the birth of agriculture about 10,000 years ago. Loss of diversity at any of the level is detrimental to the life-supporting environment of the earth and disruptive of the natural processes that are vital for biological evolution. As many of the world’s diverse life forms from microbes to higher animals and plants have a direct or indirect bearing on agriculture, conservation of these is essential for sustainable agriculture (Swaminathan and Jana, 1992). Each time we take a medicine, the chances are one in two that its origin was a wild plant. The commercial value of such drugs is around US$15 billion per year in the United States and about US$40 billion worldwide. Ecosystem stability is another compelling reason for preserving biodiversity. Nature
is beautifully balanced; each little thing has its own place, its duty and special utility. Any disturbance creates a chain reaction which may not be visible for sometime. All living organisms are an integral part of the biosphere and provide invaluable services. These include the control of pests, the recycling of nutrients, the replenishment of local climate, the control of flood etc. Civilization depends on the survival of the biological world. By conserving biodiversity at the ecosystem level, not only are the constituent species preserved, but the ecosystem functions and services are also protected. These ecosystem functions include pollutant cycling, climate control, as well
as non-consumptive recreation, and scientific values (Norton and Ulanowicz, 1992). Biodiversity also needs to be preserved for the aesthetic services it provides. According to Norman Myers “We can marvel at the colours of a butterfly, the grace of a giraffe, the power of an elephant and the delicate structure of a diatom. Every time a species goes extinct we are irreversibly impoverished. Protection of biodiversity also makes good economic sense.’’ He has further stated that, “from morning coffee to evening nightcap we benefit in out daily life style from the fellow species that share out one earth home. Without knowing it, we utilize hundreds of products each day that owe their origin to wild animals and plants. Indeed our welfare is intimately tied up with the welfare of wildlife. We may proclaim that by saving the lives of wild species, we may be saving our own’’ (Myers, 1986).
