Peter James Richerson (born October 11, 1943) is an American biologist. He is Distinguished Professor Emeritus of the Department of Environmental Science and Policy at the University of California, Davis.
Richerson studied entomology at UC Davis, earning his B.S. in 1965. In 1969, he completed his Ph.D. in zoology. After a postdoc and junior professorship, he was from 1977 until 2006 Professor of Environmental Science at UC Davis. He was a guest professor at University of California, Berkeley (1977–78), Duke University (1984), and the University of Exeter (2004). In 1991 he was a guest researcher at the Bielefeld University.
Richerson's research interests include sociocultural evolution, human ecology and applied and tropical limnology.