Institute of Zoology, Zoological Society of London, Regents Park, London NW1 4RY, UK.
Mol Ecol. 2011 Jan;20(1):29-45. doi: 10.1111/j.1365-294X.2010.04923.x. Epub 2010 Nov 12.
The maintenance of genetic diversity is thought to be fundamental for the conservation of threatened species. It is therefore important to understand how genetic diversity is affected by the re-introduction of threatened species. We use establishment history and genetic data from the remnant and re-introduced populations of a New Zealand endemic bird, the hihi Notiomystis cincta, to understand genetic diversity loss and quantify the genetic effects of re-introduction. Our data do not support any recent bottleneck events in the remnant population. Furthermore, all genetic diversity measures indicate the remnant hihi population has retained high levels of genetic diversity relative to other New Zealand avifauna with similar histories of decline. Genetic diversity (N(A) , alleles per locus, allelic richness, F(IS) and H(S) ) did not significantly decrease in new hihi populations founded through re-introduction when compared to their source populations, except in the Kapiti Island population (allelic richness and H(S) ) which had very slow post-re-introduction population growth. The N(e) /N(c) ratio in the remnant population was high, but decreased in first-level re-introductions, which together with significant genetic differentiation between populations (F(ST) & Fisher's exact tests) suggest that extant populations are diverging as a result of founder effects and drift. Importantly, simulations of future allele loss predict that the number of alleles lost will be higher in populations with a slow population growth, fewer founding individuals and with nonrandom mating. Interestingly, this species has very high levels of extra-pair paternity which may reduce reproductive variance by allowing social and floater males to reproduce a life history trait that together with a large remnant population size may help maintain higher levels of genetic diversity than expected.
维持遗传多样性被认为是保护濒危物种的基础。因此，了解遗传多样性如何受到濒危物种再引入的影响非常重要。我们利用新西兰特有鸟类——几维鸟（Notiomystis cincta）的残余和再引入种群的建立历史和遗传数据，了解遗传多样性的丧失，并量化再引入的遗传效应。我们的数据不支持残余种群最近发生瓶颈事件。此外，所有遗传多样性指标都表明，与其他具有相似衰退历史的新西兰鸟类相比，残余几维鸟种群保留了高水平的遗传多样性。与来源种群相比，通过再引入建立的新几维鸟种群的遗传多样性（N(A) 、每个位点的等位基因数、等位基因丰富度、F(IS) 和 H(S) ）没有显著降低，除了 Kapiti 岛种群（等位基因丰富度和 H(S) ），其再引入后的种群增长非常缓慢。残余种群的 N(e) /N(c) 比值较高，但在一级再引入中降低，这与种群间显著的遗传分化（F(ST) 和 Fisher 确切检验）一起表明，现存种群由于奠基者效应和漂变而发生分歧。重要的是，对未来等位基因丧失的模拟预测表明，种群增长率较慢、创始个体较少且交配非随机的种群，其等位基因丧失的数量将会更高。有趣的是，这种物种的外配对偶交配率非常高，这可能通过允许社会和游荡雄性繁殖来降低繁殖变异性，从而使其具有一个生活史特征，再加上一个较大的残余种群大小，可能有助于维持比预期更高水平的遗传多样性。
