Richard G. Klein (born April 11, 1941) is a Professor of Biology and Anthropology at Stanford University.
He earned his PhD at the University of Chicago in 1966, and was elected to the National Academy of Sciences in April 2003.
In 1962, he enrolled as a graduate student at the University of Chicago to study with the Neanderthal expert, Francis Clark Howell.
Klein completed a master's degree in 1964, and then studied at the University of Bordeaux with François Bordes, who specialized in prehistory.
These visits influenced him into believing the shift from Neanderthal to modern humans 40,000 to 35,000 years ago was sudden rather than gradual.