The limits of mtDNA phylogeography: complex patterns of population history in a highly structured Iberian lizard are only revealed by the use of nuclear markers
The limits of mtDNA phylogeography: complex patterns of population history in a highly structured Iberian lizard are only revealed by the use of nuclear markers
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DOI：
10.1111/j.1365-294x.2008.03929.x
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发表时间：
2008-11-01
影响因子：
4.9
通讯作者：
Ferrand, N.
中科院分区：
文献类型：
--
作者：
Godinho, R.;Crespo, E. G.;Ferrand, N.
基于单一使用线粒体DNA （mtDNA）分子的系统地理学分析只能揭示一个物种或一组相关物种的一小部分进化史。在这项研究中，我们将缓慢和快速进化的核标记（分别是蛋白质和微卫星）的应用与双基因谱系的分析结合起来，进一步了解伊比利亚特有的施赖伯绿蜥蜴（Lacerta schreiberi）的历史，该物种已经建立了一个良好的系统地理情景。与观察到的四个不同的、几乎是异域的mtDNA分支形成鲜明对比的是，我们的核心数据揭示了两个种群是如何沿着伊比利亚中央系统的山脉分化、持续并开始融合的。此外，mtDNA和核数据的结合显示了物种分布的核心区是如何对冰期做出反应的，首先是相对古老的种群向南扩张的过程，然后是在今天分离的起源处出现的收缩期，最近是冰川后向伊比利亚西北部的扩张，在气候改善后，那里有了新的栖息地。结合最近发表的各种其他生物的结果，我们的结果表明，只有通过使用几种互补类型的分子标记才能适当地解决破碎，膨胀和混合的复杂过程。最后，我们还认为南欧难民既是遗传多样性的热点也是大熔炉。
Phylogeographic analyses based on the sole use of the mitochondrial DNA (mtDNA) molecule reveal only a small part of the evolutionary history of a species or a set of related species. In this study, we have combined the application of slow- and fast-evolving nuclear markers (proteins and microsatellites, respectively) together with the analysis of two-gene genealogies to further understand the history of the Iberian endemic Schreiber's green lizard, Lacerta schreiberi, a species for which a well established phylogeographical scenario is available. In sharp contrast with the observation of four divergent and almost allopatric mtDNA clades, our nuclear data revealed how two groups of populations diverged, persisted and began to admix along the mountains of the Iberian Central System. In addition, the combination of mtDNA and nuclear data showed how the core area of the species distribution responded to ice ages, first by relatively old processes of population expansion to the south followed by episodes of contraction that are at the origin of present-day isolates, and more recently by a postglacial expansion to the Iberian Northwest where new habitats were made available after climatic amelioration. Taken together with recently published results for a variety of other organisms, our results suggest that complex processes of fragmentation, expansion and admixture can only be properly addressed through the use of several and complementary types of molecular markers. Finally, we also suggest that southern European refugia are both hotspots and melting pots of genetic diversity.