The differential survival and reproduction of individuals, resulting from the differences in their phenotype is known as natural selection. It is a key mechanism in evolution.

The three different types of natural selection are:

Disruptive selection

In this type of selection, extreme values have higher fitness and the mean values have disadvantages. They are subjected to divergent selection pressure in different parts of the area.

Stabilizing selection

It introduces homozygosity in a greater intensity. This favors average phenotypes and is operated in constant environments. Genetically, the population will be always constant.

Directional selection

This selection results due to the environmental change in a particular direction. This type of selection favors extreme phenotypes and mutants. The direction of mean value changes but intensity remains same.