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Environmental Science: A Global Concern, 7/e
William P. Cunningham, University of Minnesota
Mary Ann Cunningham, Vassar College
Barbara Woodworth Saigo, St. Cloud State University

Human Populations

Chapter Overview

The human population has reached unprecedented numbers due to our technological skills in medicine, improved sanitation, and food production. Ecologists feel that these numbers, along with high consumption, are the two main causes of our growing environmental problems. How many people the earth can support, at what level, and at what cost to the environment are questions in search of answers. We do know this upswing cannot continue indefinitely. Nature or human decisions eventually will rein in and level off the growth.

In developed countries, birth rates tend to fall to match the lowered death rate. This demographic transition, as the phenomenon is called, would level off the numbers were it to happen worldwide.

Science has made great strides in producing personal options to regulate our fertility. The story of human numbers touches both our most personal decisions and the fate of our species.