Cultural norms and expectations are partly built on hypotheses of opposition between sexes and genders. Sex and gender are measured on a binary scale, and culturally accepted behaviors and sanctioned activities often reflect the sexual division of labor. The sexual division of labor assigns sex roles based on the biological and anatomical differences of the two sexes. The sexual division of labor favors masculine traits over feminine traits. Created sex roles are adopted and reproduced into gender roles that reflect cultural expectations. These cultural expectations and norms reflect a preference for masculinity and legitimize male dominance in institutions and institutions.