Aaron Lukaszewski: Loyola Marymount University

Two basic questions in the study of personality origins are (1) Why do people vary in their personality trait levels? and (2) Why do distinct trait dimensions covary in consistent patterns within individuals, rather than varying independently? The current presentation describes an integrative evolutionary framework within which both of these questions can be addressed, and highlights supportive empirical findings. For instance, since physical strength and physical attractiveness likely predicted the reproductive payoffs of extraverted behavioral strategies across most of human history, it was theorized that extraversion levels are facultatively calibrated to variations in these phenotypic features. Confirming these predicted patterns, strength and attractiveness together explained a surprisingly large fraction of the variance in extraversion in Studies 1 and 2 – effects that were independent of variance explained by an androgen receptor gene polymorphism. Study 3 then provided evidence that the covariation among a wide array of interpersonal traits (e.g., extraversion, emotionality, attachment styles) is orchestrated by their facultative calibration in response to common input cues. Overall, these findings suggest that multiple types of proximate mechanisms – facultative calibration and specific gene polymorphisms – operate in concert to determine adaptively-patterned personality (co)variation.
http://bec.ucla.edu/papers/Lukaszewski_BEC.pdf