Natural Selection

Founder Effect

occurs when a portion of a large population relocates and interbreed, thus only having those alleles expressed.

Gene Flow

The movement of alleles from one population to another

Bottleneck

occurs when an originally large population falls to just a few individuals

Genetic Drift

a change in the frequency of an allele due to the random effects of limited population size

Stabilizing Selection

maintains the status quo and acts against extremes

Balancing Selection

acts to maintain two or more alleles in a population

Directional Selection

leads to a change in trait overtime

Disruptive Selection

operates in favor of extremes and against intermediate forms