Genetic drift

Genetic drift is a contributing factor in biological evolution, in which traits which do not affect reproductive fitness change in a population over time. Whereas natural selection causes traits to become more prevalent when they contribute to fitness, or eliminates those which harm it, genetic drift is a somewhat random process which affects traits that are more neutral.

Related Topics:
Evolution - Natural selection

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Genetic drift is a statistically stochastic process that arises from the role of random sampling in the production of offspring. The genes of each new generation are not a simple copy of the genes of the successful members of the previous one, but rather a sampling, which includes some statistical error. Drift is the cumulative effect over time of this sampling error on the allele frequencies in the population.

Related Topics:
Stochastic - Production of offspring - Allele frequencies

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Like selection, genetic drift acts on populations, altering the frequency of alleles (gene variations) and the predominance of traits. Drift is observed most strongly in small populations and results in changes that need not be adaptive.

Related Topics:
Trait - Small populations - Adaptive

~ ~ ~ ~ ~ ~ ~ ~ ~ ~