What is sexual selection in evolutionary terms?

• A. Traits evolve because they increase mating success due to mate preferences, such as the peacock tail
• B. Selection by predators shapes mating behaviour
• C. Climate determines which traits are favored
• D. Random mutation alone drives mate choices

Answer: (A)

Sexual selection is a form of natural selection driven by mating success rather than just survival. Traits that help an individual attract mates or win contests for access to mates spread because they increase reproductive opportunities, even if they make survival harder or cost energy. The classic example is the male peacock’s tail: its elaborate display boosts mating success by appealing to females, even though it can reduce camouflage and raise energy costs. This process includes both mate choice by one sex (intersexual selection) and competition among members of the same sex for mates (intrasexual selection). In contrast, selection driven by predators, broad environmental factors like climate, or random mutation alone does not capture why certain traits become more common specifically because they enhance mating success.