Abbott Cathryn L, Double Michael C
School of Botany and Zoology, The Australian National University, Canberra ACT 0200, Australia.
Mol Ecol. 2003 Nov;12(11):2953-62. doi: 10.1046/j.1365-294x.2003.01980.x.
Six variable microsatellite loci were used to examine genetic structuring in the closely related shy albatross (Thalassarche cauta) and white-capped albatross (T. steadi). First, levels of genetic differentiation between the species, and among three populations within each species, were analysed using amova, FST and RST. We found high levels of genetic structuring and detected many unshared alleles between the species, which provide strong evidence against any contemporary gene flow between them. Within each species, shy albatross populations were found to be genetically distinct whereas white-capped albatross populations were undifferentiated, which implies that dispersal events are much rarer in the former than in the latter. These results formed the basis for the recommendation that the three white-capped albatross populations (as a whole) and each shy albatross population be treated as separate units for conservation. Second, levels of genetic diversity and allelic patterns in shy and white-capped albatrosses were assessed for whether they support earlier mtDNA results suggesting that shy albatrosses arose through range expansion of white-capped albatrosses. All measures indicated lower genetic diversity within shy albatrosses than within white-capped albatrosses and upheld the hypothesis that shy albatrosses were founded by white-capped albatrosses.
六个可变微卫星位点被用于研究近缘的羞怯信天翁（Thalassarche cauta）和白顶信天翁（T. steadi）的遗传结构。首先，使用分子变异分析（AMOVA）、固定指数（FST）和相对标准偏差（RST）分析了两个物种之间以及每个物种内三个种群之间的遗传分化水平。我们发现了高水平的遗传结构，并检测到两个物种之间存在许多不共享的等位基因，这为它们之间不存在任何当代基因流动提供了有力证据。在每个物种内部，羞怯信天翁种群在遗传上是不同的，而白顶信天翁种群没有分化，这意味着扩散事件在前一种群中比后一种群中要罕见得多。这些结果为以下建议奠定了基础：将三个白顶信天翁种群（作为一个整体）和每个羞怯信天翁种群作为单独的保护单元来对待。其次，评估了羞怯信天翁和白顶信天翁的遗传多样性水平和等位基因模式，以确定它们是否支持早期线粒体DNA的结果，即羞怯信天翁是通过白顶信天翁的范围扩张而产生的。所有指标都表明，羞怯信天翁的遗传多样性低于白顶信天翁，并支持了羞怯信天翁是由白顶信天翁建立的假说。
