Genetic drift is one of the basic mechanisms of evolution in which the number of alleles of a population change over generations. It is most common in populations that have regular cycles of extinction and recolonization. This mechanisms occurs through chance alone as a result from sampling error throughout the generations. It can also lead to large changes in a population over a short period of time. Its effects are strongest in small populations, but can occur in any population of any size. Genetic drift leads to the alteration of alleles and can also result in the loss of some alleles, both beneficial and harmful. This increases the homozygosity. But because genetic drift occurs by chance, it is also called “random drift” or “random genetic
