What is genetic drift?

Genetic drift refers to the random fluctuations in allele frequencies within a population, particularly in small populations where chance events can have a more pronounced effect. This phenomenon occurs independently of natural selection and is a result of random sampling of alleles through generations. For instance, if a particular allele happens to be passed on more frequently than others purely by chance, its frequency can increase or decrease over time without any influence from the environmental advantages or disadvantages associated with that allele.

Genetic drift can lead to significant changes in a population's genetic makeup, potentially resulting in the loss of genetic diversity. Events such as a natural disaster can drastically reduce a population's size and alter allele frequencies unpredictably, illustrating how randomness plays a crucial role in genetic drift. This makes it especially important to understand in the context of population genetics, as it highlights the impact of stochastic processes on evolution and biodiversity.