Question

Name and define the three types of natural selection.

Answer 1

Three types of natural selection are :

1) Directional selection: It produces a regular change in a gene pool of a population in one direction in respect to one or some specific characteristics. It is a progressive selection.

2) Stabilising selection: This type of selection favours average or normal phenotypes and eliminates extreme variants. It occurs in a constant or unchanging environment and eliminates new mutations. It favours homozygosity.

3) Disruptive or diversifying selection: This type of selection acts to break up a previously homogenous population into several different adaptive norms. It favours individuals at both extremes of a distribution curve.