Question

unit exam - evolution of populations changes being made in an ecosystem. natural selection is the process of selecting traits that improve fitness and make an organism most successful in its given environment. directional selection is when individuals at one end of the curve have higher fitness than individuals in the middle or at the other end. stabilizing selection is when individuals near the center of a curve have higher fitness than individuals at either end. disruptive selection is when individuals at the upper and lower ends of the curve have higher fitness than individuals near the middle. how does natural selection change allele frequencies in populations? natural selection controls the rate of mutations. natural selection has no control over allele frequency changes. natural selection selects alleles that improve fitness.

Explanation:

Step1: Understand natural selection

Natural selection favors traits that enhance an organism's fitness in its environment.

Step2: Relate to allele frequencies

Traits are determined by alleles. So, natural - selection selects alleles for traits that boost fitness, thus changing allele frequencies in populations.

Answer:

Natural selection selects alleles that improve fitness.