nonrandom mating

genetics

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June 17, 2026

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Nonrandom mating occurs when individuals in a population choose mates based on specific traits, rather than randomly. This can include assortative mating, where individuals mate with others who are phenotypically similar to themselves (positive assortative mating), or those who are dissimilar (negative assortative mating). Another form is inbreeding, which involves mating between closely related individuals. These mating patterns can influence gene frequencies within a population, deviating from the expectations of random mating. Assortative mating is observed in both human and nonhuman populations.123

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heredity
Nonrandom mating
Many species engage in alternatives to random mating as normal parts of their cycle of sexual reproduction. An important exception is sexual selection, in which an individual chooses a mate on the basis of some aspect of the mate’s phenotype. The selection can…
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Many species engage in alternatives to random mating as normal parts of their cycle of sexual reproduction. An important exception is sexual selection, in which an individual chooses a mate on the basis of some aspect of the mate’s phenotype. The selection can…
Read More