Do We Need All These Species?

Is there reason to be concerned about the loss of life’s diversity? Do we really need such a variety of species? Many respected experts insist that the answer is yes. Earth’s endowment of species provides humans with food, useful chemicals, and many other products and services. Think, too, about the potential benefits that undiscovered species may hold for mankind. For example, it has been estimated that 120 of the top 150 prescription drugs used in the United States come from natural compounds. Thus, in losing the flora of the world, mankind also loses the opportunity to find new drugs and chemicals. “Every time we lose a species, we lose an option for the future,” says Sir Ghillean Prance, director of Kew Gardens in London. “We lose a potential cure for AIDS or a virus-resistant crop. So we must somehow stop losing species, not just for the sake of our planet but for our own . . . needs and uses.”

We also need natural ecosystems to provide essential services on which all living things depend. The production of oxygen, the purification of water, the filtering of pollutants, and the prevention of soil erosion are all vital functions performed by healthy ecosystems.

Insects provide pollination services. Frogs, fish, and birds control pests; mussels and other aquatic organisms cleanse our water supplies; plants and microorganisms create our soils. The economic value of all these services is immense. A conservative estimate of the monetary benefits of biodiversity worldwide is around 3,000 billion dollars per year, at 1995 prices.

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What Is Life Worth?

All the discussion about the value of biodiversity may seem to indicate that we should care about other life-forms only as long as they serve our needs. Some feel that such thinking is narrow-minded. Paleontologist Niles Eldredge points to the inherent value life has: “We humans also value life around us—beautiful, eye-catching species, gorgeous intact wild places—for its intrinsic worth. Something within us recognizes that we are connected to this natural world and that we gain peace and pleasure from being in it whenever we can.”