10.3 Gene pools and speciation
These charts depict the different types of genetic selection. On each graph, the x-axis variable is the type of phenotypic trait and the y-axis variable is the amount of organisms. Group A is the original population and Group B is the population after selection.
Graph 1 shows directional selection, in which a single extreme phenotype is favored.
Graph 2 depicts stabilizing selection, where the intermediate phenotype is favored over the extreme traits.
Graph 3 shows disruptive selection, in which the extreme phenotypes are favored over the intermediate.