Nancy L. Segal (born March 2, 1951, Boston, Massachusetts) is a prominent American evolutionary psychologist and behavioral geneticist, specializing in the study of twins.
Dr. Segal was awarded a Ph.D., Committee on Human Development, University of Chicago, Chicago (1982); M.A., Division of Social Sciences, University of Chicago, Chicago, IL (1974); and a B.A., Psychology (with Honors) and English Literature, Double Major, Boston University, Boston, MA (1973).
Dr. Segal is currently Professor of Developmental Psychology and Director of the Twin Studies Center, at California State University, Fullerton. She was recognized as CSU Fullerton's 2004-5 Outstanding Professor of the Year, as well as the 2004-5 Distinguished Professor in Humanities and Social Sciences. Dr. Segal also received the 2005 James Shields Award for Lifetime Contributions to Twin Research from the Behavior Genetics Association and International Society for Twin Studies.
Dr. Segal is a Fellow of the American Psychological Association, American Psychological Society and Western Psychological Association. She has been inducted into the Collegium of Distinguished Alumni at Boston University. Dr. Segal is an Associate Editor for the journal Twin Research and Human Genetics and was Contributing Research Editor for Twins Magazine from 1984–1998 and is a member of the Advisory Board for the Center for Loss in Multiple Birth. She served as Assistant Director of the Minnesota Center for Twin and Adoption Research, in the Department of Psychology at the University of Minnesota, in Minneapolis, 1985-1991. She has appeared on Good Morning America, The Oprah Winfrey Show, Dateline NBC and the Today Show, in addition to other nationally and locally televised programs. Her research interests include genetic and environmental influences on human behavior, especially social relationships and bereavement. Her research program includes twin and adoption studies that are specially designed to address problems and issues concerning human development in general, and twin development in particular.