Effects of Mother and Father Dominance on Offspring Sex in Contemporary Humans

Variation in human sex ratios has been the focus of empirical investigation for decades, but no studies have examined the relationship between parental mating behavior and future offspring sex. Here we tested whether dominance cues in the faces and behavior of mothers and fathers were associated with the sex of their future offspring. Our results show that maternal facial cues indicating lower dominance status may be associated with increased probability of a daughter as a first-born child, but only when moderated by high paternal facial dominance. We also show that both mother and father’s dominance behavior increases the probability of a first-born son. These results suggest that the effect of maternal dominance on the sex of offspring depends on the dominance of their male partner; however, future research should investigate additional characteristics that influence long-term mating decisions in women according to future offspring sex.