Measuring drift by mean deviation: unequal breeding sex ratio revisited

Abstract

When it comes to estimating the magnitude of genetic drift, there is hardly any indexes other than the effective population size. Starting from the binomial sampling distribution, this research proposed using mean deviation of allele frequency change as a direct measurement of drift, then tested it in a classical example concerning unequal breeding sex ratio. This study found that: (1) mean deviation offers a new dimension in measuring the magnitude of drift; (2) the measurement displays a "half-half" pattern; (3) allele frequency determines the efficacy of hitchhiking effect of rare alleles, and in what way that "half-half" pattern should be divided.