When imbalances occur in the sex ratio of sexual species that have two sexes (i.e., other than a 50:50 ratio), the members of the minority sex often receive a greater proportion of care and resources from parents than do the offspring of the majority sex. This is most clearly an example of

Question

Quizplus · Accepted Answer

This is an example of frequency-dependent selection, where the fitness of a phenotype depends on its frequency relative to other phenotypes in a given population. In this case, the rarity of one sex increases its reproductive value, leading to increased parental investment.

When Imbalances Occur in the Sex Ratio of Sexual Species