Answer to Question #123532 in Evolution for NIBEDITA RUDRA

Question

Distinguish between interspecific sterility and hybrid sterility. How have these mechanism helped to maintain the uniqueness of species?

Answer 1

Hybrids between different species within the same genus are sometimes known as interspecific hybrids or crosses.The offspring of an interspecific cross very often are sterile, this hybrid sterility prevents the movement of genes from one species to the other, keeping both species distinct. Sterility is often attributed to the different number of chromosomes the two species have.

Hybrid sterility is defined as the inhibition or suppression of the reproductive capacity of F1 or later generation hybrids between genetically different strains or populations, usually belonging to different species. It is a reproductive isolating mechanism which functions to prevent the exchange of genes between populations. Naturalists view that species, when intercrossed are especially endowed with the quality of sterility in order to prevent the confusion of all organic forms. Hybrid sterility for instance is a reproductive isolating mechanism and reproductive isolation cannot be separated from the origin of sterility.