How does the process of natural selection affect Hardy-Weinberg equilibrium? List the other four factors that disturb the equilibrium.

Explanation

Natural selection refers to the fitness of the individual or population. Those organisms who are better fit in an environment outbreds others and leave more progeny than others in natural conditions. These, therefore survive more and hence are selected by nature.
Types of natural selection. Operation of natural selection on different trails is of three types :
(i) Stabilising more individuals acquire mean character value.
(ii) Directional more individuals acquire value other than the mean character value.
(iii) Disruptive more individuals acquire peripheral character value at both ends of distribution curve.
The other four factors that disturb the genetic equilibrium are :-
(i) Gene flow/migration. The movement of a section of population from one place to another, results in the addition of new alleles to the local gene pool of the host population. This is called gene migration. Migration causes variations at the genetic level.
(ii) Genetic drift. The random changes in gene frequency in a population occurring by chance alone rather than by natural selection is called genetic drift. The effects of genetic drift are more prominent in small populations.
(iii) Mutation. Pre-existing advantageous mutations when selected, result in new phenotypes and over few generations would result in speciation.
(iv) Recombination. Variations due to recombination during gametogenesis result in changed frequency of genes and alleles in future generation. Reproduction increases the variants and natural selection, makes it different population.