Paul Ehrlich, founder and first president of the Zero Population Growth organization, was born in Philadelphia, Pennsylvania. He received a B.A. in zoology from the University of Pennsylvania in 1953 and an M.A. and Ph.D. from the University of Kansas in 1955 and 1957, respectively. He became a member of the faculty at Stanford University in 1959 and was named Bing Professor of Population Studies in 1976. He is a recipient of a MacArthur Foundation fellowship, and in 1990 he was awarded Sweden's Crafoord Prize, created by the Royal Swedish Academy of Sciences to honor researchers in those disciplines not covered by the Nobel Prize. An expert in population biology, ecology, evolution, and… behavior, Ehrlich has published more than 600 articles and scientific papers. He is perhaps best known for his environmental classic The Population Bomb (1968). Paul Ehrlich and his wife Anne began working together shortly after their marriage in 1954. Anne Ehrlich received her B.S. in biology from the University of Kansas. As senior research associate in biology and associate director of the Center for Conservation Biology at Stanford University, she has lectured widely and written on various environmental issues, including the environmental consequences of nuclear war. Together, the Ehrlichs have written six books and dozens of magazine articles.
A respected planetary scientist best known outside the field for his popularizations of astronomy, Carl Sagan was born in New York City on November 9, 1934. He attended the University of Chicago, where he received a B.A. in 1954, a B.S. in 1955, and a M.S. in 1956 in physics as well as a Ph.D. in 1960 in astronomy and astrophysics. He has several early scholarly achievements including the experimental demonstration of the synthesis of the energy-carrying molecule ATP (adenosine triphosphate) in primitive-earth experiments. Another was the proposal that the greenhouse effect explained the high temperature of the surface of Venus. He was also one of the driving forces behind the mission of… the U.S. satellite Viking to the surface of Mars. He was part of a team that investigated the effects of nuclear war on the earth's climate - the "nuclear winter" scenario. Sagan's role in developing the "Cosmos" series, one of the most successful series of any kind to be broadcast on the Public Broadcasting System, and his book The Dragons of Eden (1977) won the Pulitzer Prize in 1978. He also wrote the novel Contact, which was made into a movie starring Jodie Foster. He died from pneumonia on December 20, 1996.