Multi-level patterns in population genetics: variogram series detects a hidden isolation-by- distance- dominated structure of Scandinavian brown bears Ursus arctos

1. Large-scale pattern-oriented approaches are useful to understand the multi-level processes that shape the genetic structure of a population. Matching the scales of patterns and putative processes is both a key to success and a challenge. 2. We have developed a simple statistical approach, based on variogram analysis, that identifies multiple spatial scales where the population pattern, in this case genetic structure, have highest expression (i.e. the spatial scales at which the strength of patterning of isolation-by-distance (IBD) residual variance reached maximum) from empirical data and, thus, at which scales it should be studied relative to the underlying processes. The approach is applicable to any spatially explicit pairwise data, including genetic, morphological or ecological distance or similarity of individuals, populations and ecosystems. To exemplify possible applications of this approach, we analysed microsatellite genotypes of 1,530 brown bears from Sweden and Norway. 3. ...

1. 面向模式的大规模研究方法，有助于解析塑造种群遗传结构的多层级过程。匹配模式与推定过程的对应尺度，既是研究取得成功的关键，也是一项颇具难度的挑战。2. 本研究开发了一种基于变异函数（variogram）分析的简易统计方法，可从实证数据中识别出种群模式（此处指代遗传结构）表现最强的多个空间尺度——即距离隔离（isolation-by-distance, IBD）残差方差的模式强度达到峰值的空间尺度，进而明确应针对哪些尺度开展与内在过程相关的研究。该方法适用于各类空间显式成对数据，涵盖个体、种群及生态系统间的遗传、形态或生态距离或相似性数据。为示例该方法的潜在应用场景，我们对采自瑞典与挪威的1530头棕熊的微卫星基因型（microsatellite genotypes）进行了分析。3. ...