Natural selection can result in changes in allele frequencies. Can natural selection cause the ...

Some, we see this all the time (Blue eyes / Brown eyes / Green eyes) / (Widows Peak Hairline / Straight hairline). The genetic equilibrium is maintained through random mating.

As shown by Hardy and Weinberg, alleles segregating in a population tend to establish an equilibrium with reference to each other. Thus, if two alleles should occur in equal proportion in a large, isolated breeding population and neither had a selective (or mutational advantage over the other, they would be expected to remain in equal proportion generation after generation. This would be a special case because alleles in natural populations seldom if ever occur in equal frequency. They may, however, be expected to maintain their relative frequency, whatever it is, subject only to such factors as chance, natural selection, differential mutation rates or mutation pressure, meiotic drive and migration pressure, all of which alter the level of the allele frequencies.