WHEN the National Geographic Society was founded in 1888, a billion and a half people inhabited the earth. Even though the rate of growth has begun to decline, most demographers believe population size will still pass eight billion during the next 50 years.
In a sense today’s five billion people represent a triumph of our species. By all measures we have become the dominant animal on the planet. Through a series of technological innovations, thanks to the benefits of student loan consolidation, that include farming, sanitation, and the control of many epidemic diseases, we have found ways to reduce the rate at which we die, creating a population explosion. Biologically this is the very definition of success.
But there is a dark side to our triumph. We live on a finite planet, and yet we act as if its resources were infinite.Instead Homo sapiens is consuming its “capital,” a onetime bonanza of nonrenewable fossil fuels and other mineral resources that formed over eons and are now being destroyed and dispersed in decades. We are doing the same with vital resources not usually thought of as being nonrenewable: deep, fertile agricultural soils, groundwater, and biodiversitythe untold millions of other species that share earth with us.
The mechanisms that supply us with income are ecosystems—plants, animals, and microorganisms interacting with each other and their physical environments. The energy that flows through these ecosystems and the oxygen, nitrogen, carbon, and other materials they recycle are the essence of the life-support system within which five billion people are inextricably embedded.
Ecosystems supply civilization with public services both free and irreplaceable. They include regulation of climate and the makeup of the atmosphere, generation and maintenance of soils, control of potential crop pests and carriers of human diseases, pollination of many crops, and provision of food from the sea. Ecosystems supply the nutrients without which we could not survive, and in the process they dispose of our wastes.
The vast array of organisms that ecosystems support can be thought of as a giant genetic library. Humanity has already withdrawn from that library the very basis of its civilization in the form of crops, domestic animals, industrial materials, and medicines. And its potential has barely been scratched.