What is the primary effect of sexual dimorphism in evolution?

Sexual dimorphism refers to the distinct difference in size or appearance between the sexes of an animal species. This phenomenon plays a significant role in evolution primarily through its impact on sexual selection. Sexual selection is a form of natural selection where individuals with certain inherited characteristics are more likely than others to obtain mates.

The primary effect of sexual dimorphism is that it enhances mating success by creating distinct traits that can be preferred during mate selection. For example, male peacocks have large, colorful tails that attract peahens, while females often prefer mates with the most impressive displays. As a result, these traits are passed on more frequently to the next generation.

This process of sexual selection can lead to the evolution of exaggerated traits that improve an individual's chances of reproduction, further solidifying the link between sexual dimorphism and mating success. Therefore, the correct answer reflects the significant role that sexual dimorphism plays in driving sexual selection, ultimately influencing which individuals are more successful in breeding and contributing to the evolution of species.