Islands within an island: Population genetic structure of the endemic Sardinian newt, Euproctus platycephalus.
Islands within an island: Population genetic structure of the endemic Sardinian newt, Euproctus platycephalus.
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DOI：
10.1002/ece3.2665
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发表时间：
2017-02
影响因子：
2.6
通讯作者：
Garner TW
中科院分区：
文献类型：
--
作者：
Ball SE;Bovero S;Sotgiu G;Tessa G;Angelini C;Bielby J;Durrant C;Favelli M;Gazzaniga E;Garner TW
识别历史和当代的扩散障碍是保护濒危两栖动物的核心，但它们复杂的生活史和难以捉摸的性质可能会阻碍它们的扩散。线粒体（mtDNA）和微卫星标记产生的互补信息为阐明种群结构和栖息地破碎化的影响提供了有价值的工具。我们将这种方法应用于一种濒危的山地蝾螈——白头Euproctus platycephalus。它是地中海撒丁岛的特有物种，受到人为活动、疾病和气候变化的威胁。我们已经证明了在遗传上不同和空间上不同的亚种群中有一个清晰的结构层次。三个主要山区之间的差异决定了这两个标记的遗传分配。线粒体系统地理学揭示了大约100万年前（Mya）的深层分裂，分离了北部地区，并在大约0.5 Mya时进一步区分了中部和南部地区，表明与更新世严重的冰川振荡有关。我们的发现与冰期山脉向南扩张的模式一致，冰期后山脉退缩到山地栖息地，随后发生遗传隔离。微卫星标记进一步揭示了较强的种群结构，在中部地区表现出明显的分化，在南部地区表现出部分分化。北方种群的遗传多样性下降。在这个尺度上，线粒体和微卫星标记之间的不一致表明了种群结构的进一步复杂性，与雄性偏向分散和雌性偏好保持一致。我们的研究强调了在疾病和气候变化的背景下，有必要阐明濒危岛屿限制两栖动物的生态和保护策略中的隐种群结构。
The identification of historic and contemporary barriers to dispersal is central to the conservation of endangered amphibians, but may be hindered by their complex life history and elusive nature. The complementary information generated by mitochondrial (mtDNA) and microsatellite markers generates a valuable tool in elucidating population structure and the impact of habitat fragmentation. We applied this approach to the study of an endangered montane newt, Euproctus platycephalus. Endemic to the Mediterranean island of Sardinia, it is threatened by anthropogenic activity, disease, and climate change. We have demonstrated a clear hierarchy of structure across genetically divergent and spatially distinct subpopulations. Divergence between three main mountain regions dominated genetic partitioning with both markers. Mitochondrial phylogeography revealed a deep division dating to ca. 1 million years ago (Mya), isolating the northern region, and further differentiation between the central and southern regions ca. 0.5 Mya, suggesting an association with Pleistocene severe glacial oscillations. Our findings are consistent with a model of southward range expansion during glacial periods, with postglacial range retraction to montane habitat and subsequent genetic isolation. Microsatellite markers revealed further strong population structure, demonstrating significant divergence within the central region, and partial differentiation within the south. The northern population showed reduced genetic diversity. Discordance between mitochondrial and microsatellite markers at this scale indicated a further complexity of population structure, in keeping with male‐biased dispersal and female philopatry. Our study underscores the need to elucidate cryptic population structure in the ecology and conservation strategies for endangered island‐restricted amphibians, especially in the context of disease and climate change.