In a particular mouse species, two extremes of a phenotype are equally selected for over several generations. as a result, the genetic frequency for these two phenotypes begins to increase over the preexisting mean trait. what type of selection has occurred?

The image shows the evolution of a species of fish. a few fish from a population developed different social behaviors and evolved into different species. two fish according to the image, the fish underwent . the new species of fish had mating seasons that were different from that of the original fish. because of the differences in mating seasons, the fish underwent reproductive isolation. this mode of isolation would be .