Kaeuffer Renaud, Coltman David W, Chapuis Jean-Louis, Réale Denis, Pontier Dominique
Département des Sciences Biologiques, Université du Québec à Montréal, CP 8888 succursale centre-ville, Montréal, QC, Canada H3C 3P8.
Mol Ecol. 2007 Nov;16(21):4482-92. doi: 10.1111/j.1365-294X.2007.03501.x. Epub 2007 Sep 14.
The Haute Island mouflon (Ovis aries) population is isolated on one small (6.5 km2) island of the remote Kerguelen archipelago. Given a promiscuous mating system, a cyclic demography and a strong female-biased sex ratio after population crashes, we expected a low effective population size (Ne). We estimated Ne using demographic and temporal genetic approaches based on genetic information at 25 microsatellite loci from 62 and 58 mouflons sampled in 1988 and 2003, respectively. Genetic Ne estimates were higher than expected, varying between 104 and 250 depending on the methods used. Both demographic and genetic approaches show the Haute Island Ne is buffered against population crashes. The unexpectedly high Ne likely results from the cyclic winter crashes that allow young males to reproduce, limiting the variance of male reproductive success. Based on individual-based simulations, we suggest that despite a strongly female-biased sex ratio, the effects of the mating system on the effective population size more closely resemble random mating or weak polygyny.
奥特岛摩弗伦羊（盘羊）种群孤立于遥远的凯尔盖朗群岛中一个面积仅6.5平方公里的小岛上。鉴于其混交的交配系统、周期性的种群统计学特征以及种群数量崩溃后严重的雌性偏向性性别比例，我们预计其有效种群大小（Ne）较低。我们分别根据1988年和2003年采集的62只和58只摩弗伦羊在25个微卫星位点的遗传信息，采用种群统计学和时间遗传学方法来估计Ne。遗传Ne估计值高于预期，根据所使用的方法不同，在104到250之间变化。种群统计学和遗传学方法均表明，奥特岛的Ne对种群数量崩溃具有缓冲作用。Ne出乎意料地高，可能是由于周期性的冬季种群数量崩溃使得年轻雄性得以繁殖，从而限制了雄性繁殖成功率的方差。基于个体模拟，我们认为，尽管性别比例严重偏向雌性，但交配系统对有效种群大小的影响更类似于随机交配或轻度多配。
