Campbell R B
Department of Mathematics, University of Northern Iowa, Cedar Falls, Iowa 50614-0506, USA.
Theor Popul Biol. 1999 Jun;55(3):260-9. doi: 10.1006/tpbi.1998.1402.
Selection ultimately entails differential reproductive success over several generations. This can be measured as a correlation of the number of progeny an individual has with the number of progeny its parent had. This correlation could have a genetic or a cultural basis. The effect of such a correlation is to multiply the single generation sampling variance (Vdeltap) in the diffusion approximation for fixation time by (1-b)+bx(1+r)/(1-r), where bxrn is the correlation between the number of progeny of an individual and its ancestor n generations ago (e.g., b is the heritability and br is the resultant parent-offspring progeny number correlation if the progeny number is genetically determined). This results in a reduction of the fixation or coalescent time by division by this factor. Sex differences in this correlation have been observed, and this provides an explanation for the difference of coalescent times of y-chromosomes and mitochondria.
选择最终需要在几代人中实现不同的繁殖成功率。这可以通过个体拥有的后代数量与其亲本拥有的后代数量之间的相关性来衡量。这种相关性可能有遗传或文化基础。这种相关性的影响是，在固定时间的扩散近似中，将单代抽样方差（Vdeltap）乘以(1 - b) + bx(1 + r)/(1 - r)，其中bxrn是个体与其n代前祖先的后代数量之间的相关性（例如，如果后代数量由基因决定，b是遗传力，br是由此产生的亲子后代数量相关性）。这导致通过除以这个因子来减少固定或合并时间。已经观察到这种相关性中的性别差异，这为Y染色体和线粒体合并时间的差异提供了解释。
