Directional SelectionDirectional Selection is a type of selection that favors individuals at one end of the phenotypic range. Directional selection can happen in response to certain selective pressures. They are reasons that certain phenotypes lead to a fitness advantage or disadvantage.
Ex. Peppered moths are a perfect example of directional selection. During the Industrial Revolution, soot covered trees making them dark in color. Dark colored moths were able to camouflage themselves from predators. This selective pressure caused the moths to adapt and favor the darker phenotype in order to survive. This will shift the bell curve either left or right to one phenotypic extreme. |