Subterranean archipelago in the Australian arid zone: mitochondrial DNA phylogeography of amphipods from central Western Australia
Subterranean archipelago in the Australian arid zone: mitochondrial DNA phylogeography of amphipods from central Western Australia
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DOI：
10.1111/j.1365-294x.2007.03261.x
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发表时间：
2007-04-01
影响因子：
4.9
通讯作者：
Humphreys, William F.
中科院分区：
文献类型：
--
作者：
Cooper, Steven J. B.;Bradbury, John H.;Humphreys, William F.
1998年，在西澳大利亚干旱的Yilgarn地区的许多孤立的钙质结砾岩（碳酸盐）含水层中发现了一个独特的地下生态系统。先前对地下水甲虫动物群的形态学和遗传学分析表明，钙质结层含水层相当于封闭的岛屿栖息地，已被隔离了数百万年。我们进一步测试了这一假设的地下端足类动物（Crangonyctoidea：Paramelitidae和Hyalidae）的线粒体DNA序列数据来自细胞色素氧化酶I基因的地理分析。系统发育分析和种群遗传分析（samova）提供了强有力的证据，至少有16 crangonyctoid和6个透明的分歧线粒体谱系的存在，每个限制在其分布到一个单一的钙质结层含水层，在支持“地下岛屿（群岛）假说”，并扩大其范围，包括完全水呼吸无脊椎动物。近端钙质砾岩种群之间的序列差异估计表明，钙质砾岩已被隔离至少自上新世以来，正好与一个主要的干旱阶段，导致地表水的间歇性干燥。石灰岩的分布沿着古排水渠道和排水分水岭的两侧，有较小的影响，对人口的整体生态地理结构，有证据表明，祖先crangonyctoid和玻璃体物种之间的集水区多次移动之前，他们的隔离在石灰岩。至少有两种潜在的进化模式可以解释地下端足类种群的多样性：硬骨鱼物种的扩散/替代或地表物种对石灰岩的定殖以及硬骨鱼特征的独立进化。
In 1998, a unique subterranean ecosystem was discovered in numerous isolated calcrete (carbonate) aquifers in the arid Yilgarn region of Western Australia. Previous morphological and genetic analyses of a subterranean water beetle fauna suggest that calcrete aquifers are equivalent to closed island habitats that have been isolated for millions of years. We tested this hypothesis further by phylogeographic analyses of subterranean amphipods (Crangonyctoidea: Paramelitidae and Hyalidae) using mitochondrial DNA sequence data derived from the cytochrome oxidase I gene. Phylogenetic analyses and population genetic analyses (samova) provided strong evidence for the existence of at least 16 crangonyctoid and six hyalid divergent mitochondrial lineages, each restricted in their distribution to a single calcrete aquifer, in support of the 'subterranean island (archipelago) hypothesis' and extending its scope to include entirely water respiring invertebrates. Sequence divergence estimates between proximate calcrete populations suggest that calcretes have been isolated at least since the Pliocene, coinciding with a major aridity phase that led to the intermittent drying of surface water. The distribution of calcretes along palaeodrainage channels and on either side of drainage divides, have had less influence on the overall phylogeographic structure of populations, with evidence that ancestral crangonyctoid and hyalid species moved between catchments multiple times prior to their isolation within calcretes. At least two potential modes of evolution may account for the diversity of subterranean amphipod populations: dispersal/vicariance of stygobitic species or colonization of calcretes by surface species and independent evolution of stygobitic characteristics.