Odum School of Ecology, University of Georgia, Athens, GA 30602, USA.
Mol Ecol. 2009 Nov;18(22):4664-79. doi: 10.1111/j.1365-294X.2009.04378.x. Epub 2009 Oct 8.
Historical (phylogenetic) biogeography and community ecology were once integrated as part of the broader study of organismal diversity, but in recent decades have become largely separate disciplines. This is unfortunate because many patterns studied by community ecologists may originate through processes studied by historical biogeographers and vice versa. In this study, we explore the causes of a geographic pattern of community structure (habitat use) in the emydid turtle assemblages of eastern North America, with more semi-terrestrial species of the subfamily Emydinae in the north and more aquatic species of Deirochelyinae in the south. Specifically, we address the factors that prevent northern emydines from invading southern communities. We test for competitive exclusion by examining patterns of range overlap, and test for the role of niche conservatism using analyses of climatic and physiological data based on a multilocus molecular phylogeny. We find no support for competitive exclusion, whereas several lines of evidence support the idea that niche conservatism has prevented northern emydines from dispersing into southern communities. Our results show how understanding the causes of patterns of historical biogeography may help explain patterns of community structure.
历史（系统发育）生物地理学和群落生态学曾经是作为生物多样性更广泛研究的一部分而结合在一起的，但在最近几十年已成为两个独立的学科。这很不幸，因为许多群落生态学家研究的模式可能是由历史生物地理学家研究的过程引起的，反之亦然。在这项研究中，我们探讨了北美东部的淡水龟亚科龟类群落结构（栖息地利用）的地理模式的原因，北部有更多半陆生的 Emydinae 物种，而南部则有更多水生的 Deirochelyinae 物种。具体来说，我们解决了阻止北部淡水龟类入侵南部群落的因素。我们通过检查范围重叠模式来检验竞争排斥的作用，并通过基于多基因分子系统发育的气候和生理数据的分析来检验生态位保守性的作用。我们没有发现竞争排斥的证据，而有几条证据支持生态位保守性阻止了北部淡水龟类扩散到南部群落的观点。我们的结果表明，了解历史生物地理学模式的原因如何有助于解释群落结构的模式。
