No one today can afford to ignore the impact of the human species on its environment. In this topical volume, distinguished international authors identify and analyze areas of rapid and serious change, and outline approaches to some of the outstanding fundamental questions concerning the environment. The opening chapter places the present environmental crisis in a chronological perspective, exploring the changing impact of human populations on the environment since prehistoric times, with particular reference to forest cover, soil erosion and animal extinctions. The contributors then focus in detail on the future of the forests, the impact of man on the animal species and his coexistence with them, on the problems of famine and the Earth's exhaustible resources, and on the likely effect of man's activities on the atmosphere and global climatic patterns. In closing, a NASA scientist puts these and other environmental problems into a new perspective, as the environment is examined from space.