title: The role of culture-gene coevolution in morality judgment: examining the interplay between tightness-looseness and allelic variation of the serotonin transporter gene.
abstract: This research provides novel insights into the evolutionary basis of cultural norm development and maintenance. We yield evidence for a unique culture-gene coevolutionary model between ecological threat, allelic frequency of the serotonin transporter polymorphism (5-HTTLPR), cultural tightness-looseness-the strength of norms and tolerance for deviance from norms-and moral justifiability. As hypothesized, the results across 21 nations show that: (a) propensity for ecological threat correlates with short (S) allele frequency in the 5-HTTLPR, (b) allelic frequency in the 5-HTTLPR and vulnerability to ecological threat both correlate with cultural tightness-looseness, (c) susceptibility to ecological threat predicts tightness-looseness via the mediation of S allele carriers, and (d) frequency of S allele carriers predicts justifiability of morally relevant behavior via tightness-looseness. This research highlights the importance of studying the interplay between environmental, genetic, and cultural factors underlying contemporary differences in social behavior and presents an empirical framework for future research.
authors.affiliation: Department of Psychology, Northwestern University, Swift Hall, 2029 Sheridan Rd., Evanston, IL 60208 USA.
authors.forename: Alissa J
authors.initials: AJ
authors.lastname: Mrazek
authors.affiliation: Department of Psychology, Northwestern University, Swift Hall, 2029 Sheridan Rd., Evanston, IL 60208 USA ; Interdepartmental Neuroscience Program, Northwestern University, Chicago, IL 60611 USA.
authors.forename: Joan Y
authors.initials: JY
authors.lastname: Chiao
authors.affiliation: Interdepartmental Neuroscience Program, Northwestern University, Chicago, IL 60611 USA ; Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, IL 60611 USA.
authors.forename: Katherine D
authors.initials: KD
authors.lastname: Blizinsky
authors.affiliation: Department of Psychology, University of Maryland, College Park, MD 20742 USA.
authors.forename: Janetta
authors.initials: J
authors.lastname: Lun
authors.affiliation: Department of Psychology, University of Maryland, College Park, MD 20742 USA.
authors.forename: Michele J
authors.initials: MJ
authors.lastname: Gelfand
keywords: 5-HTTLPR; Culture–gene coevolution; Moral justifiability; Serotonin transporter gene; Tightness–looseness