Synonyms
Definition
Balanced polymorphism or balancing selection is a phenomenon by which more than one morph exists in the population at a stable frequency at a given time.
Introduction
Polymorphism refers to the occurrence of two or more forms of phenotypes in a population. Balanced polymorphism occurs in a population when alleles exist in a population in stable frequencies due to selection. The term balanced polymorphism was coined by an ecological geneticist F.B. Ford (1901–1988). The superiority of heterozygotes over the homozygotes allows the maintenance of balanced polymorphism in population. This heterozygote superiority is also referred as overdominance or single locus heterosis. Under balanced polymorphism, there is neither the fixation of alleles nor the elimination of alleles. If the heterozygote of any mutation is fitter than the mutant homozygote and confers an adaptive advantage, then the mutation is maintained at an intermediate, balanced frequency...
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References
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Bhumika (2017). Balanced Polymorphism. In: Vonk, J., Shackelford, T. (eds) Encyclopedia of Animal Cognition and Behavior. Springer, Cham. https://doi.org/10.1007/978-3-319-47829-6_50-1
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DOI: https://doi.org/10.1007/978-3-319-47829-6_50-1
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