Final answer:
Sexual selection creates stronger selection pressure on males to obtain multiple copulation partners due to their higher reproductive potential. This leads to the evolution of traits that help males attract mates. Females, with limited reproductive opportunities, tend to be more selective in choosing mates.
Step-by-step explanation:
Sexual selection leads to stronger selection pressure on males than on females to obtain numerous copulation partners. This is because males generally have a higher potential for reproductive success compared to females. In many species, some males have a greater chance of mating multiple times and fathering more offspring, while other males may not have the opportunity to mate at all. This variation in reproductive success generates a strong selection pressure among males to compete for and attract as many mates as possible, resulting in the evolution of traits such as larger body size, elaborate ornaments, and colorful plumage to attract female attention. Females, on the other hand, typically have more limited reproductive opportunities and therefore tend to be more selective in choosing mates.