Michael J. O’Brien was born in Houston in 1950 and graduated from St. Thomas High School in Houston in 1968.
His undergraduate degree is from Rice University (1972) and his Ph.D. from The University of Texas at Austin (1977). After graduation he served as a research associate at the University of Nebraska–Lincoln until 1980, when he joined the University of Missouri as an assistant professor of anthropology and director of the American Archaeology Division, the research arm of the anthropology department. He became director of the Museum of Anthropology several years later and joined the College of Arts and Science dean’s office as associate dean for research. He was promoted to the rank of professor in 1989 and became dean of arts and science in 2006 following a national search. He was provost and chief academic officer at Texas A&M University–San Antonio from 2016 until 2021.
O’Brien is best known for his work in evolutionary archaeology and biology and has authored or edited 26 books and written over 150 articles, which have appeared in journals such as Science, Journal of the Royal Society Interface, Nature Human Behaviour, Philosophical Transactions of the Royal Society, Behavioral and Brain Sciences, Journal of Human Evolution, and Journal of Theoretical Biology. O’Brien and his wife, Gloria, have five grown children.