Question

What are the two major mechanisms of genetic drift?

Answer 1

Genetic drift:

1. Genetic drift is a mechanism by which the allele frequencies of a population get changed over generations due to chance.
2. This occurs in all very large populations but effects could be seen in small populations.

Mechanisms of genetic drift:

1. Founder effect: The founder effect is one that occurs when a small group of individuals breaks off or gets isolated from a larger population to establish a colony. This isolated new colony from the original population, and the founding individuals might not represent the full genetic diversity of the original population.
2. Bottleneck effect: According to this when the size of a population is severely reduced events like natural calamities (earthquakes, floods, fires) can reduce a population, leading to the death of most individuals and leaving behind small, random survivors.