Comparative population genetics of seven notothenioid fish species reveals high levels of gene flow along ocean currents in the southern Scotia Arc, Antarctica
Comparative population genetics of seven notothenioid fish species reveals high levels of gene flow along ocean currents in the southern Scotia Arc, Antarctica
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DOI：
10.1007/s00300-012-1155-x
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发表时间：
2012-07-01
期刊：
影响因子：
1.7
通讯作者：
Hanel, Reinhold
中科院分区：
文献类型：
--
作者：
Damerau, Malte;Matschiner, Michael;Hanel, Reinhold
南极鱼类区系的特点是特有性高且物种多样性低，鲈形目一个亚目——南极鱼亚目（Notothenioidei）在大陆架和大陆坡的整个物种组合中占主导地位。南极鱼通过适应性辐射在原地发生分化，成年个体呈现出从底栖到浮游等多种生活史策略。它们的幼体发育时间异常长，从几个月到一年多不等，并且通常包括一个浮游幼体阶段。因此，卵和幼体随洋流的平流是调节种群连通性的关键因素。在此，我们基于核微卫星和线粒体DNA序列（D - 环/细胞色素b）比较了南斯科舍弧的七种生态特征明显不同的南极鱼亚目物种的遗传种群结构和基因流。这七个物种分别属于南极鱼科（隆头南极鱼Gobionotothen gibberifrons、鳞头南极鱼Lepidonotothen squamifrons、真狼绵鳚Trematomus eulepidotus、纽氏绵鳚T. newnesi）和鳄冰鱼科（棘吻南极鱼Chaenocephalus aceratus、裘氏鳄头冰鱼Champsocephalus gunnari、长吻鳄头冰鱼Chionodraco rastrospinosus）。我们的研究结果表明，所有被研究的物种都呈现出低种群分化和高基因流的特征，这与它们成年个体的生活史策略无关。此外，基因流主要与盛行的洋流系统一致，这凸显了幼体扩散在南极鱼种群结构形成中的作用。
The Antarctic fish fauna is characterized by high endemism and low species diversity with one perciform suborder, the Notothenioidei, dominating the whole species assemblage on the shelves and slopes. Notothenioids diversified in situ through adaptive radiation and show a variety of life history strategies as adults ranging from benthic to pelagic modes. Their larval development is unusually long, lasting from a few months to more than a year, and generally includes a pelagic larval stage. Therefore, the advection of eggs and larvae with ocean currents is a key factor modulating population connectivity. Here, we compare the genetic population structures and gene flow of seven ecologically distinct notothenioid species of the southern Scotia Arc based on nuclear microsatellites and mitochondrial DNA sequences (D-loop/cytochrome b). The seven species belong to the families Nototheniidae (Gobionotothen gibberifrons, Lepidonotothen squamifrons, Trematomus eulepidotus, T. newnesi) and Channichthyidae (Chaenocephalus aceratus, Champsocephalus gunnari, Chionodraco rastrospinosus). Our results show low-population differentiation and high gene flow for all investigated species independent of their adult life history strategies. In addition, gene flow is primarily in congruence with the prevailing ocean current system, highlighting the role of larval dispersal in population structuring of notothenioids.