Final answer:
Intersexual selection is a type of sexual selection that favors certain male traits that are deemed attractive by females, causing these traits to become more common in the population.
Step-by-step explanation:
Intersexual selection is a type of sexual selection that increases the frequency of male traits or behaviors that females find most attractive.
Sexual selection is a mechanism of evolution which contributes to the differences between male and female phenotypes, commonly known as sexual dimorphism. This process operates when individuals of one sex develop features that are favored by the other sex during mate selection. The peacock's tail is a classic example where females may select males with larger, more colorful tails, as it signals genetic superiority. Consequently, selected traits become more prevalent as they are passed on to the offspring. Alongside, concepts like the good genes hypothesis suggest that such ornamental traits are indicators of a male's genetic fitness.
The impact of sexual selection is also visible in species like the common side-blotched lizards, where males display different throat-color patterns, each associated with distinct mating strategies. For example, frequency-dependent selection is at play among these lizards, where orange males, blue pair-bonded males, and yellow 'sneaker' males each have strategies that work best against one another in a rock-paper-scissors manner. The handicap principle further explains how some traits, while detrimental to survival, can still be advantageous for reproduction.