James William Schopf is an American paleobiologist and professor of earth sciences at the University of California Los Angeles. He is also Director of the Center for the Study of Evolution and the Origin of Life, and a member of the Department of Earth and Space Sciences, the Institute of Geophysics and Planetary Physics, and the Molecular Biology Institute at UCLA. He is most well known for his study of Precambrian prokaryotic life in Australia's Apex chert. Schopf has published extensively in the peer reviewed literature about the origins of life on Earth. He is the first to discover Precambrian microfossils in stromatolitic sediments of Australia (1965), South Africa (1966), Russia (1977), India (1978), and China (1984). He served as NASA's principal investigator of lunar samples during 1969–1974.