Evolution, situational affordances, and the HEXACO model of personality

The existence of individual differences in personality can be puzzling from an evolutionary perspective. This paper offers a general framework for addressing this puzzle by combining insights from evolutionary, situational, and personality perspectives. To arrive at this framework, we first discuss three key evolutionary models for explaining personality variation: (1) selective neutrality, (2) mutation-selection balance, and (3) balancing selection. Second, we review four models of personality: (1) the general factor of personality, (2) the big two, (3) the big five, and (4) the six-dimensional HEXACO model. Third, we use situational affordances and trait activation perspectives to offer an integrative model of HEXACO domain-specific situational affordances. Finally, we use these perspectives to provide 18 propositions about situation, trait, and outcome activation (STOA) mechanisms which may help explain the maintenance of individual differences in six dimensions of personality.