Robert M. Sapolsky is a professor of biology and neurology at Stanford University and a research associate with the Institute of Primate Research, National Museum of Kenya. He is the author of "Why Zebras Don't Get Ulcers", "A Primate's Memoir" and "The Trouble with Testosterone", which was a "Los Angeles Times" Book Award finalist. A regular contributor to "Discover" and "The Sciences", and a recipient of a MacArthur Foundation "genius" grant, he lives in San Francisco.