Adolescent leadership and adulthood fertility: revisiting the "central theoretical problem of human sociobiology".

Human motivation for social status may reflect an evolved psychological adaptation that increased individual reproductive success in the evolutionary past. However, the association between status striving and reproduction in contemporary humans is unclear. It may be hypothesized that personality traits related to status achievement increase fertility even if modern indicators of socioeconomic status do not. We examined whether four subcomponents of type-A personality--leadership, hard-driving, eagerness, and aggressiveness--assessed at the age of 12 to 21 years predicted the likelihood of having children by the age of 39 in a population-based sample of Finnish women and men (N=1,313). Survival analyses indicated that high adolescent leadership increased adulthood fertility in men and women, independently of education level and urbanicity of residence. The findings suggest that personality determinants of status achievement may predict increased reproductive success in contemporary humans.