Abstract
The genetic mechanism underlying an ‘Optimal outcrossing distance’ in plants (sensu Price and Waser) is discussed. Monte Carlo simulations of a population subdivided as a one-dimensional stepping-stone are used to evaluate possible genetic mechanisms. A simple genetic model with two types of unlinked loci, underdominant and partially dominant, with multiplicative effects on fitness, is found to create an ‘Optimal outcrossing distance’ under a wide range of parameter values. The results are compared to, and discussed in relation to a two-locus epistatic model, previously investigated by Campbell and Waser, and found to give very similar results.
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Schierup, M., Christiansen, F. Inbreeding depression and outbreeding depression in plants. Heredity 77, 461–468 (1996). https://doi.org/10.1038/hdy.1996.172
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DOI: https://doi.org/10.1038/hdy.1996.172
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