Research suggests that Y-linked genetic variance may play a role in the rapid evolution of sexual size dimorphism. Studies on various species, including water striders, fruit flies, and red junglefowl, have investigated the relationship between genetic variation and sex differences in traits such as body size and locomotor activity. The findings appear to contribute to a broader understanding of the quantitative genetics of sexual dimorphism, although the extent to which males are larger than females in different species remains a subject of study.