Terrestrial Ecology Unit, Ghent University, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium.
Mol Ecol. 2011 Nov;20(22):4643-53. doi: 10.1111/j.1365-294X.2011.05316.x. Epub 2011 Oct 18.
Understanding factors that shape patterns of kinship in sedentary species is important for evolutionary ecologists as well as conservation biologists. Yet, how patterns of relatedness are hierarchically structured in space remains poorly known, even in common species. Here, we use information from 16 polymorphic microsatellite DNA markers to study how small-scale kinship structure varies among house sparrows (Passer domesticus) along an urban-rural gradient. Average levels of relatedness were higher among urban individuals than among individuals from rural areas, suggesting lower rates of dispersal in more built-up habitats. Comparison of observed levels of relatedness with simulated distributions of known kinship values showed that central urban individuals had the highest proportion of closely related conspecifics in their immediate neighbourhood. Spatial auto-correlograms supported this small-scale genetic structure and further indicated stronger effects of genetic drift and/or limited dispersal in urban populations. Results of this study underscore the importance of individual-level analyses as a complementary approach to traditional population-level analyses when studying genetic population structure over small spatial scales.
了解定居物种亲属关系模式形成的因素对进化生态学家和保护生物学家都很重要。然而，即使在常见物种中，亲属关系模式在空间上的层次结构如何仍然知之甚少。在这里，我们使用来自 16 个多态微卫星 DNA 标记的信息来研究家麻雀（Passer domesticus）在城市-农村梯度上的小尺度亲属关系结构如何变化。与农村个体相比，城市个体的亲缘关系平均值更高，这表明在建筑密度更高的栖息地中，扩散率更低。将观察到的亲缘关系水平与已知亲缘关系值的模拟分布进行比较表明，中心城市个体在其邻近地区具有最高比例的近亲同种个体。空间自相关图支持这种小规模的遗传结构，并进一步表明遗传漂变和/或在城市种群中有限的扩散具有更强的影响。这项研究的结果强调了个体水平分析的重要性，这是研究小空间尺度上遗传种群结构时对传统种群水平分析的一种补充方法。
