. Advances in herpetology and evolutionary biology : essays in honor of Ernest E. Williams. Williams, Ernest E. (Ernest Edward); Herpetology; Evolution. Relatedness and Recombination • Seiner 601 their expression. Thus there seems to be no simple way to apply genotypic co- variance methods (Price, 1970; Seger, 1980, 1981) to the evolution of recombi- nation modifiers. But positive selection for increased recombination can be demonstrated by simulation of a particu- lar model with many signalling loci. One such simulation is described below. The model species is a diploid hermaphrodite in which
. Advances in herpetology and evolutionary biology : essays in honor of Ernest E. Williams. Williams, Ernest E. (Ernest Edward); Herpetology; Evolution. Relatedness and Recombination • Seiner 601 their expression. Thus there seems to be no simple way to apply genotypic co- variance methods (Price, 1970; Seger, 1980, 1981) to the evolution of recombi- nation modifiers. But positive selection for increased recombination can be demonstrated by simulation of a particu- lar model with many signalling loci. One such simulation is described below. The model species is a diploid hermaphrodite in which self-fertilization alternates with random mating. The population is infinitely large, but the effective population size is finite, owing to the high frequency of selfing. Off- spring are produced in pairs. Each pair is given one unit of resource (x), and an individual's fitness (W) depends on the amount of resource it consumes, accord- ing to the function W(x) = Given this fitness function and total shareable resource, the fitness set for sibling pairs is slightly convex (Fig. 3). One sibling, called "left," divides the unit of resource between itself and the other sibling, called "; Locus A controls the left sibling's di- vision of the unit of resource, and locus C controls the rate of recombination at B, a large array of signalling loci to which neither A nor C is linked. In the simula- tion, A and C are treated explicitly, but B is treated in the aggregate. Typical loci in B are imagined to be highly polymorphic, such that outbred individuals are always more heterozygous than inbred indi- viduals, if recombination between B loci is free. C^ causes free recombination between all B loci, and Cq suppresses recombination between them. In some runs C^ was dominant to Cq , and in others it was recessive. The behavior of this genetic system can be described as follows. All of the selfed progeny of recombining parents are moderately homozygous a
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Keywords: ., bookauthorharvarduniver, bookcentury1900, booksubjectherpetology
