What do we call the change in a gene pool of a population due to chance?

The change in a gene pool of a population due to chance is termed genetic drift. This concept is vital in understanding how allele frequencies can fluctuate randomly over time within a population, especially in smaller groups. Unlike natural selection, which is driven by the reproductive success of individuals based on advantageous traits, genetic drift occurs without regard to the fitness of the alleles involved.

Genetic drift can lead to the loss or fixation of alleles, which may significantly affect the genetic diversity of a population. It highlights the randomness inherent in evolutionary processes, contrasting with the more deterministic nature of natural selection. For example, in a population where a certain allele is only present in a few individuals, a random event such as a natural disaster can significantly reduce the population size and, consequently, the genetic variation available, leading to a change in the gene pool.

By understanding genetic drift, one gains insight into the evolutionary dynamics of populations and how chance events can shape genetic diversity over time. This fundamental concept is foundational in anthropology and evolutionary biology, illustrating how genetic changes can occur independent of adaptive advantages.