Genetic Drift Flashcards

Vocabulary flashcards covering key terms and concepts related to genetic drift, coalescence, founder effects, and their impact on evolution.

Genetic Drift

Random fluctuations in allele or haplotype frequencies over generations.

Natural Selection

A nonrandom process of selection for and against certain phenotypes.

Nonadaptive evolution

Evolution that is not driven by adaptive needs; random fluctuations in alleles do not result in adaptations

Fixation

Loss of alleles leads to 100% of only one kind of allele.

Coalescence

Fixation of an allele by random events, where any fixed allele in a population can be traced back to a single common gene ancestor.

Bottleneck/Founder Effect

Restrictions in population size; when a new population is formed by a small number of colonists, resulting in random genetic drift.

Population Bottleneck

An evolutionary event in which a population's size is drastically reduced, potentially leading to a loss of genetic diversity.

Probability of Fixation

The principle that an allele's probability of fixation by drift equals its frequency.

Rate of Decrease in Heterozygotes

The rate at which the frequency of heterozygotes decreases, used as a measure of the rate of genetic drift.