Abstract

Objectives Strategic Pluralism Theory contends that human mating strategies are calibrated toward short-term (ST) or long-term (LT) mating according to the expression of condition-dependent traits and characteristics of the social and physical environment. Traits reflecting the effects of testosterone have been considered condition-dependent traits that provide information about the calibration of male mating strategy. We investigated the relationship of muscle mass and facial masculinity with attitudes and behaviors reflecting ST and LT mating tactics. Methods We measured skeletal muscle mass (SMM) through bioelectrical impedance and facial width-to-height ratio (fWHR) in a sample of Chilean men (n = 206; mean age = 22.52 +/- 4.65 SD), and collected information about sociosexual attitudes and past sexual behavior. Results Our results showed an interaction effect of SMM and fWHR on unrestricted (but not restricted) sociosexual attitudes and past sexual behavior. Individuals with a consistent expression of both traits (ie, high SMM and fWHR or low SMM and fWHR) reported higher levels of unrestricted sociosexual attitudes and a greater number of lifetime and previous-year sexual partners. Conclusions These findings suggest that the intensity and consistency of expression of body and facial masculinity is important in signaling male mating tactics and sociosexual attitudes.