Final answer:
Snow geese selecting mates of their own color is an example of assortative mating, a form of nonrandom mating based on phenotype similarity that can affect population characteristics.
Step-by-step explanation:
Snow geese usually select mates of their own color, which is an example of assortative mating. This is a type of nonrandom mating where individuals have a preference to mate with partners who are similar in phenotype, such as coloration, to themselves. Various forms of mate choice, including assortative mating, can lead to changes in population characteristics over time. Females are often more selective than males in choosing mates, leading to processes such as sexual selection, where certain traits may become more pronounced within a species, sometimes without offering any survival advantage. These traits, however, are attractive to the opposite sex and therefore become more prevalent in the population due to increased mating success.