- Genetic admixture occurs when individuals from two or more previously separated populations begin interbreeding. It results in the introduction of new genetic lineages into a population. It has been known to slow local adaptation by introducing foreign, unadapted genotypes and also prevents formation of newer species by homogenizing populations (bringing back the genotype to its old constitution).
- It occurs when any geographic barrier, such as a river or an isthmus, that previously prevented two organisms for breeding is removed, or when human activities result in movement of animal populations.
- Admixture mapping is a method of gene mapping that makes use of population of mixed ancestry to find the point of location of the gene that contributes to differences in diseases or other external characteristics.