tionary history of a “warrior” gene. Science 304:818; Lea, R, & Chambers, G. (2007). Monoamine oxidase, addiction, and the “warrior” gene hypothesis. J. New Zealand Medical Association, 120(1250), 1- 5; Meyer-Lindenberg, A., Buckholtz, J.W., Kolachana, B., Hariri, A., Pezawas, L., Blasi, G., Weinberger, D.R. (2006). Neural mechanism