outbreeding

biology

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July 1, 2026

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Outbreeding, also known as outcrossing, is the interbreeding of individuals or stocks that are relatively unrelated. This biological process is the opposite of inbreeding, which involves mating closely related individuals.12

Outbreeding is a strategy that brings gametes of different genotypes together, resulting in offspring that differ from their parents. This increased variation provides greater evolutionary flexibility. In contrast, inbreeding maintains uniform genotypes, which can be advantageous in stable environments but often leads to decreased vigor, size, and fertility in offspring due to the expression of harmful recessive genes. Selective breeding, a practice used in animal husbandry, utilizes natural variations within populations. While inbreeding can concentrate desirable traits, outbreeding is employed to introduce genetic diversity.3245

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inbreeding
…common ancestry, as opposed to outbreeding, which is the mating of unrelated organisms. Inbreeding is useful in the retention of desirable characteristics or the elimination of undesirable ones, but it often results in decreased vigour, size, and fertility of the offspring because of the combined effect of harmful genes that…
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…common ancestry, as opposed to outbreeding, which is the mating of unrelated organisms. Inbreeding is useful in the retention of desirable characteristics or the elimination of undesirable ones, but it often results in decreased vigour, size, and fertility of the offspring because of the combined effect of harmful genes that…
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heredity
Nonrandom mating
… (mating with relatives) and enforced outbreeding. Both can shift the equilibrium proportions expected under Hardy-Weinberg calculations. For example, inbreeding increases the proportions of homozygotes, and the most extreme form of inbreeding, self-fertilization, eventually eliminates all heterozygotes.
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… (mating with relatives) and enforced outbreeding. Both can shift the equilibrium proportions expected under Hardy-Weinberg calculations. For example, inbreeding increases the proportions of homozygotes, and the most extreme form of inbreeding, self-fertilization, eventually eliminates all heterozygotes.
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Myrtales
Natural history
…highly specialized mechanism for promoting outcrossing (pollination with pollen from another individual) is widespread in Lythraceae, where members of Lythrum, Decodon, and Nesaea have three flower forms on different plants (trimorphism); plants with two flower forms (dimorphic) are known in toothcup (Rotala) and in Lythrum. As such, the style and…
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…highly specialized mechanism for promoting outcrossing (pollination with pollen from another individual) is widespread in Lythraceae, where members of Lythrum, Decodon, and Nesaea have three flower forms on different plants (trimorphism); plants with two flower forms (dimorphic) are known in toothcup (Rotala) and in Lythrum. As such, the style and…
Read More