- BS Media
- Published: 11, Jun, 2017 | Updated: June 11, 2017
i) Geographical Isolation: Two parts of one population are separated by some geographical barrier and arc prevented from interbreeding. Large bodies of water are barriers for land-dwelling animals. High Mountain ranges, deserts, dense forests and extremes of temperature serve as affective barriers. Such populations are completely ‘out of touch with each other genetically’ so that new mutations, genetic drift and the action of natural selection, in one population have rio effect on the other population. Thus, a new population may be developed.
vi) Hybrid Sterility: Normal vigorous hybrids are formed but they are sterile and further exchange of genes is completely blocked. The Mule is a classical example of hybrid sterility.