David Cyril Geary (born June 7, 1957, in Providence, Rhode Island) is a United States cognitive developmental and evolutionary psychologist with interests in mathematical learning and sex differences. He is currently a Curators’ Professor and Thomas Jefferson Fellow in the Department of Psychological Sciences and Interdisciplinary Neuroscience Program at the University of Missouri in Columbia, Missouri. Career Geary received a BS degree in psychology from Santa Clara University (California) in 1979, and an MS from the clinical child/school psychology program at California State University at Hayward (now East Bay) in 1981. After completing the MS degree, he worked for the emergency treatment center of the Mental Research Institute in Palo Alto, California, and began the Ph.D. program at the University of California, Riverside, in 1982. His initial interests were in hemispheric laterality and associated sex differences, but focused his dissertation work on mathematical cognition under the direction of Keith Widaman (now at UC, Davis). After completing his Ph.D. in developmental psychology in 1986, he took a one-year position at the University of Texas at El Paso and then moved to the University of Missouri, first at the Rolla campus (1987–1989) and then in Columbia. During this time, he served as chair of the Department of Psychological Sciences (2002–2005) and contributed heavily to the creation of the Ph.D. program in developmental psychology. Geary's wide-ranging interests are reflected in invited addresses in a variety of departments (anthropology, biology, behavior genetics, computer science, education, government, mathematics, neuroscience, physics, and psychology) and Universities throughout the United States, as well as in Canada, Europe, and East Asia. Geary's research on mathematics learning, evolutionary psychology, and sex differences has been featured in many popular press outlets, including Discover, Education Week, Forbes, CBS News, and MSNBC among many others. Geary's research on children's mathematical development resulted in a MERIT award from the National Institutes of Health (NIH). In 2005, the University of Missouri awarded Geary a Curators’ Professorship, and the Thomas Jefferson Professorship in 2009. Among other distinctions, he is 2009 co-recipient of the George A. Miller Award for an Outstanding Recent Article on General Psychology for the 2007 Psychological Science in the Public Interest monograph on sex differences in mathematics and science, co-authored with Halpern, Benbow, Gur, Hyde, and Gernsbacher. He is a fellow of the Association for Psychological Science (2005) and the American Association for the Advancement of Science (2011). Public service Geary contributed to