等待物种形成：种群细分对物种形成时间的影响。

WAITING FOR SPECIATION: THE EFFECT OF POPULATION SUBDIVISION ON THE TIME TO SPECIATION.

作者信息

Orr H Allen, Orr Lynne H

机构信息

Department of Biology, University of Rochester, Rochester, New York, 14627.

Department of Physics and Astronomy, University of Rochester, Rochester, New York, 14627.

出版信息

Evolution. 1996 Oct;50(5):1742-1749. doi: 10.1111/j.1558-5646.1996.tb03561.x.

DOI:10.1111/j.1558-5646.1996.tb03561.x

PMID:28565607

Abstract

We study the time required for speciation in a species that is divided into small versus large populations. Following Dobzhansky and Muller, we assume that hybrid sterility or inviability is caused by "complementary genes," that is, by the accumulation of genes that cause sterility or inviability when brought together in hybrids but that have no deleterious effect on their normal species genetic background. When divergence between populations is caused by genetic drift, we show that the time to speciation is independent of population subdivision: speciation occurs just as quickly in a species split into a few large populations as into many small populations. When divergence is driven by natural selection, however, the time to speciation is very sensitive to population subdivision and speciation occurs most rapidly when a species is split into two large populations. These results contradict several popular intuitions about the effect of population size on speciation.

摘要

我们研究了一个物种在被划分为小种群和大种群时形成新物种所需的时间。遵循多布赞斯基和穆勒的观点，我们假设杂种不育或不存活是由“互补基因”引起的，也就是说，是由那些在杂种中聚集在一起时会导致不育或不存活，但对其正常物种遗传背景没有有害影响的基因的积累所导致的。当种群间的分化是由遗传漂变引起时，我们表明形成新物种的时间与种群细分无关：一个物种分裂成几个大种群时形成新物种的速度与分裂成许多小种群时一样快。然而，当分化是由自然选择驱动时，形成新物种的时间对种群细分非常敏感，当一个物种分裂成两个大种群时，形成新物种的速度最快。这些结果与一些关于种群大小对物种形成影响的流行直觉相矛盾。