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PubMed · 14991236

Sex ratio evolution through group selection using diffusion approximation.

Josiane Courteau·Sabin Lessard
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Abstract

We consider a haploid, hermaphrodite population subdivided into an infinite number of demes of finite size N. Assuming recurrent mutation, random union of gametes, partial dispersal, genetic drift, and incorporating group competition, a diffusion approximation is used to describe the evolution of sex ratio, corresponding to sex allocation to male versus female functions. The stationary distribution is deduced. In presence of group selection, a female-biased sex ratio in the whole population is found to be optimal in the sense that an allele coding for this sex ratio is always more frequent at equilibrium when segregating with another allele coding for a different sex ratio than for the same sex ratio. Numerical studies are presented to check the validity and accuracy of this prediction.

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AlgorithmsAnimalsBiological EvolutionCompetitive BehaviorDisorders of Sex DevelopmentFemaleGene FrequencyGenetic DriftGenetics, PopulationGenotypeGerm CellsHaploidyMaleModels, GeneticMutationPopulation DynamicsSelection, GeneticSex RatioJournal ArticleResearch Support, Non-U.S. Gov't

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Josiane Courteau, Sabin Lessard. 2003-10-27. Sex ratio evolution through group selection using diffusion approximation.. https://doi.org/10.1007/s00285-003-0240-8

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