Ecol Evol. 2012 Jun;2(6):1220-34. doi: 10.1002/ece3.84.
The biogeography of islands is often strongly influenced by prior geological events. Corucia zebrata (Squamata: Scincidae) is endemic to the geologically complex Solomon Archipelago in Northern Melanesia. We examined the level of divergence for different island populations of C. zebrata and discussed these patterns in light of Pleistocene land bridges, island isolation, and island age. Corucia zebrata was sampled from 14 locations across the Solomon Archipelago and sequenced at two mitochondrial genes (ND2 and ND4; 1697 bp in total) and four nuclear loci (rhodopsin, an unknown intron, AKAP9, and PTPN12). Measures of genetic divergence, analyses of genetic variation, and Bayesian phylogenetic inference were used and the data assessed in light of geological information. Populations of C. zebrata on separate islands were found to be genetically different from each other, with reciprocal monophyly on mitochondrial DNA. Populations on islands previously connected by Pleistocene land bridges were marginally less divergent from each other than from populations on other nearby but isolated islands. There are indications that C. zebrata has radiated across the eastern islands of the archipelago within the last 1-4 million years. Nuclear loci were not sufficiently informative to yield further information about the phylogeography of C. zebrata on the Solomon Archipelago. Analyses of the mitochondrial data suggest that dispersal between islands has been very limited and that there are barriers to gene flow within the major islands. Islands that have been isolated during the Pleistocene glacial cycles are somewhat divergent in their mitochondrial genotypes, however, isolation by distance (IBD) and recent colonization of isolated but geologically younger islands appear to have had stronger effects on the phylogeography of C. zebrata than the Pleistocene glacial cycles. This contrasts with patterns reported for avian taxa, and highlights the fact that biogeographic regions for island species cannot be directly extrapolated among taxa of differing dispersal ability.
岛屿的生物地理学通常受到先前地质事件的强烈影响。 Corucia zebrata（有鳞目：石龙子科）是北美拉尼西亚所罗门群岛特有的物种。我们检查了 C. zebrata 不同岛屿种群的分歧程度，并根据更新世陆桥、岛屿隔离和岛屿年龄讨论了这些模式。 Corucia zebrata 从所罗门群岛的 14 个地点采集，并在两个线粒体基因（ND2 和 ND4；总共 1697 bp）和四个核基因座（视紫红质，一个未知内含子，AKAP9 和 PTPN12）上进行了测序。使用遗传分歧度量、遗传变异分析和贝叶斯系统发育推断，并根据地质信息评估数据。发现彼此分离的岛屿上的 C. zebrata 种群在遗传上彼此不同，在线粒体 DNA 上具有互惠单系性。曾经通过更新世陆桥连接的岛屿上的种群彼此之间的分歧程度略低于其他附近但孤立的岛屿上的种群。有迹象表明，C. zebrata 在过去 1-400 万年内在群岛的东部岛屿上辐射。核基因座没有提供足够的信息来进一步了解 C. zebrata 在所罗门群岛的系统地理学。线粒体数据分析表明，岛屿之间的扩散非常有限，并且在主要岛屿内存在基因流动的障碍。在更新世冰川循环中被隔离的岛屿在其线粒体基因型上有些分歧，但是，隔离距离（IBD）和最近对孤立但地质上较年轻的岛屿的殖民化似乎对 C. zebrata 的系统地理学产生了比更新世冰川循环更强的影响。这与鸟类分类群的报告模式形成对比，突出了一个事实，即岛屿物种的生物地理区域不能直接推断为具有不同扩散能力的分类群之间。
