How Can Evolutionary Psychology Successfully Explain Personality and Individual

Although evolutionary psychology has been successful in explaining some species-typical and sex- differentiated adaptations, a large question that has largely eluded the field is this: How can the field success- fully explain personality and individual differences? This article highlightssomepromising theoretical directions for tackling this question. These include life-history theory, costlysignalingtheory,environmentalvariabilityinfitness optima, frequency-dependent selection, mutation load, and flexibly contingent shifts in strategy according to envi- ronmental conditions. Tackling the explanatory question also requires progress on three fronts: (a) reframing some personality traits as forms of strategic individual differ- ences; (b) providing a nonarbitrary, evolutionary-based formulation of environments as distributions and salience profiles of adaptive problems; and (c) identifying which strategies thrive and which falter in these differing prob- lem-defined environments.