"The Population Bomb," 1968

Paul Ehrlich, an entomologist, and his wife, Anne Howland, who studied population biology, agreed that population-growth threatened human survival by outstripping available food supplies. They wrote The Population Bomb during the 1968 presidential campaign to stress the proactive steps necessary to reduce overpopulation. The topic exploded in February 1970, when Johnny Carson interviewed Ehrlich on The Tonight Show.