Abstract Humans rely on a suite of fundamental social motives to navigate recurring adaptive challenges. Using data from 14 532 participants across 42 societies, we examine sex similarities and differences in the strength of these motives across adulthood and sociocultural contexts, employing generalized additive models that account for spatial autocorrelation. Across societies, women reported stronger motivation for threat avoidance, long-term pair bonding and caregiving, while men reported stronger motivation for status and mate-seeking. These sex differences were largest among individuals in committed partnerships without children but were smallest—approximately halved—among parents. Men who were fathers reported motivational profiles more oriented towards protection and caregiving, aligning more closely with women’s profiles in ways suggesting a shared parental care strategy. However, fathers also reported amplified status motivation relative to mothers, suggesting a sex-differentiated strategy that may complement caregiving through resource provision. Notably, sex differences in motive strength are maintained or even amplified in societies with greater gender equality, suggesting that such contexts may facilitate fuller expression of sex-linked motivational patterns. These findings highlight how fundamental social motives reflect sex-specific calibration and vary across life phases and sociocultural conditions that shape human social behaviour.
Ko et al. (2026) studied this question.