Question

What are two common causes of genetic drift?

Answer 1

Genetic drift :

1. It is a mechanism by which evolution develops over generations.
2. It is due to a change in allele frequencies of a population that occurs by chance.

Causes of Genetic drift :

1. Genetic drift usually occurs in populations of few members.
2. A small population has many alleles, and if any of the alleles become extinct it will lead to variations.
3. In a larger population, there is less chance of losing a whole allele.
4. As many organisms contain alleles and all the alleles cannot be removed away.
5. If the allele alters the organism's function such that it leads to more reproduction of DNA, the frequency of the allele increases.
6. When alleles damage an organism, the frequency of alleles decreases.
7. When the frequency of alleles increases or decreases due to being present in a randomly surviving organism, it is called genetic drift.
8. Hence, mutations and random allelic changes in small populations collectively lead to genetic drift.