Department of Biology, Queen's University, Kingston, ON, Canada.
J Evol Biol. 2011 Nov;24(11):2364-77. doi: 10.1111/j.1420-9101.2011.02362.x. Epub 2011 Aug 16.
Contemporary geographical range and patterns of genetic diversity within species reflect complex interactions between multiple factors acting across spatial and temporal scales, and it is notoriously difficult to disentangle causation. Here, we quantify patterns of genetic diversity and genetic population structure using mitochondrial DNA sequences (101 individuals, cytochrome b) and microsatellites (816 individuals, 12 loci) and use Approximate Bayesian computation methods to test competing models of the demographic history of eastern and western foxsnakes. Our analyses indicate that post-glacial colonization and past population declines, probably caused by the infilling of deciduous forest and cooler temperatures since the mid-Holocene, largely underpin large-scale genetic patterns for foxsnakes. At finer geographical scales, our results point to more recent anthropogenic habitat loss as having accentuated genetic population structure by causing further declines and fragmentation.
当代物种的地理分布范围和遗传多样性模式反映了多种因素在时空尺度上的复杂相互作用，要理清因果关系非常困难。在这里，我们使用线粒体 DNA 序列（101 个个体，细胞色素 b）和微卫星（816 个个体，12 个位点）来量化遗传多样性和遗传种群结构的模式，并使用近似贝叶斯计算方法来测试东部和西部狐蛇的人口历史竞争模型。我们的分析表明，冰川后殖民化和过去的种群减少，可能是由于落叶林的填充和中全新世以来温度降低，这在很大程度上支持了狐蛇的大规模遗传模式。在更精细的地理尺度上，我们的结果表明，最近人为的栖息地丧失通过进一步的减少和破碎化，加剧了遗传种群结构。
