Answer:
atural selection can cause microevolution (change in allele frequencies), with fitness-increasing alleles becoming more common in the population.
Fitness is a measure of reproductive success (how many offspring an organism leaves in the next generation, relative to others in the group).
Natural selection can act on traits determined by alternative alleles of a single gene, or on polygenic traits (traits determined by many genes).
Natural selection on traits determined by multiple genes may take the form of stabilizing selection, directional selection, or disruptive selection.
Step-by-step explanation: