10.3 Gene pools and speciation

Stabilising, directional and disruptive selection


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.



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