Killer whales differentiating in geographic sympatry facilitated by divergent behavioural traditions.
Killer whales differentiating in geographic sympatry facilitated by divergent behavioural traditions.
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不同的行为传统促进了虎鲸在地理同情上的差异。
DOI：
10.1038/hdy.2016.112
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发表时间：
2016
期刊：
影响因子：
3.8
通讯作者：
Hoelzel AR
中科院分区：
文献类型：
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作者：
Hoelzel AR
Foote和Morin（2016）重新分析了我们最近的RADseq研究中发表的数据（莫拉等人，2014年a，2015年），以解决北太平洋虎鲸种群同域性分化的可能性问题。然而，他们描述了同域分化的流行版本，需要生殖隔离从泛混居的背景下通过“生态驱动的破坏性选择”进化。正如他们所指出的，人们对维持与生态型和生殖隔离相关的基因座之间的连锁的可能性提出了质疑，尽管有一些令人信服的推定的同域物种形成的例子（例如，Gavrilets et al.，2007年）。然而，我们强调空间/时间隔离在这一过程中的潜在作用，正如许多作者所做的那样（例如，Mallet等人，2009年）。我们一直在描述虎鲸的一个过程，即"猎物定位和捕获的社会促进"（Hoelzel等人，2007）导致资源专家对不同的空间和时间栖息地的使用，即使占据重叠的地理范围，并建议这促进了遗传漂变和选择的连续交配和分化（例如，Hoelzel等人，2007;莫拉等人，2014 a，2015）。我们同意，异域与同域分化的二分法可能过于简单，而是考虑一个更好地反映真实的世界的连续体。与此同时，还有一个重要的区别。Foote和Morin（2016）提出，北太平洋不同生态类型的出现是通过与异地进化的种群混合而产生的。相反，我们认为，尽管不同海洋中的种群之间可能存在基因流动（我们在Pilot等人的文章中提供了太平洋和大西洋之间存在这种联系的证据）。（2009年）以及莫拉等人关于太平洋和南大洋之间的关系的研究。（2014年a），生态和社会因素在同一海洋内运作可能足以解释那里的差异。同样明显的是，类似的生态类型差异（例如，海洋哺乳动物和鱼类捕食者的单独种群）发生在不同的海洋中（见de Bruyn等人，Foote和Morin（2016）使用了我们的人口基因组学论文（莫拉等人，2014a）以基于各种过滤器生成约1300个SNP的子样本。我们在我们的基因组论文中解决了许多相同的问题（莫拉等人，2015），例如去除选择下的离群值（包括来自GATA 4基因的离群值），并过滤出映射伪影（与莫拉等人中的不同，最终数据集使用不同的基因型调用策略）。（2014年a））。我们还通过划分GC含量评估了串联的潜在偏倚
Foote and Morin (2016) reanalyse data published in our recent RADseq studies (Moura et al., 2014a, 2015) to address questions about the likelihood of differentiation in sympatry among killer whale populations in the North Pacific. However, they describe a demic version of sympatric differentiation, requiring reproductive isolation to evolve by ‘ecologically driven disruptive selection’from a background of panmixia. As they point out, questions have been raised about the potential for maintaining linkage between loci associated with ecotype and reproductive isolation, though there are some convincing putative examples of sympatric speciation by this mechanism (for example, Gavrilets et al., 2007). However, we emphasise the potential role of spatial/temporal segregation in the process, as have various authors (for example, Mallet et al., 2009). We have consistently described a process for killer whales whereby the ‘social facilitation of prey location and capture’(Hoelzel et al., 2007) leads resource specialists to differential spatial and temporal habitat use, even while occupying overlapping geographic ranges, and suggested that this promotes assortative mating and differentiation by both genetic drift and selection (for example, Hoelzel et al., 2007; Moura et al., 2014a, 2015). We agree that the dichotomous idea of allopatric vs sympatric differentiation is likely too simple, and instead consider a continuum that better reflects the real world. At the same time, there is an important distinction. Foote and Morin (2016) propose that the appearance of distinct ecotypes in the North Pacific has been seeded by admixture with populations evolving in allopatry. We instead suggest that although there may be gene flow among populations in different oceans (and we have provided evidence for such a connection between the Pacific and Atlantic in Pilot et al.(2009) and between the Pacific and Southern Oceans in Moura et al.(2014a), ecological and social factors operating within the same ocean could be sufficient to explain differentiation there. It is also apparent that similar ecotype differences (for example, separate populations of marine mammal and fish predators) occur in different oceans (see de Bruyn et al., 2013), and so requiring inter-oceanic admixture to promote this seems less parsimonious than the alternative of independent events driven by a similar mechanism (for example, resource specialisation) at each location.Foote and Morin (2016) used the full single nucleotide polymorphisms (SNPs) data set from our population genomics paper (Moura et al., 2014a) to generate a subsample of~ 1300 SNPs based on various filters. We address a number of the same issues in our phylogenomic paper (Moura et al., 2015) such as removing outliers under selection (including from the GATA4 gene), and filtering out mapping artefacts (with a different genotype calling strategy used for the final data set than in Moura et al.(2014a)). We also evaluated potential bias from concatenation by partitioning for GC content