当前位置: X-MOL 学术Syst. Biol. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Ecological Divergence and the History of Gene Flow in the Nearctic Milksnakes ( Lampropeltis triangulum Complex)
Systematic Biology ( IF 6.5 ) Pub Date : 2021-11-17 , DOI: 10.1093/sysbio/syab093
Frank T Burbrink 1 , Justin M Bernstein 2 , Arianna Kuhn 1 , Marcelo Gehara 3 , Sara Ruane 3, 4
Affiliation  

Many phylogeographic studies on species with large ranges have found genetic–geographic structure associated with changes in habitat and physical barriers preventing or reducing gene flow. These interactions with geographic space, contemporary and historical climate, and biogeographic barriers have complex effects on contemporary population genetic structure and processes of speciation. While allopatric speciation at biogeographic barriers is considered the primary mechanism for generating species, more recently it has been shown that parapatric modes of divergence may be equally or even more common. With genomic data and better modeling capabilities, we can more clearly define causes of speciation in relation to biogeography and migration between lineages, the location of hybrid zones with respect to the ecology of parental lineages, and differential introgression of genes between taxa. Here, we examine the origins of three Nearctic milksnakes (Lampropeltis elapsoides, Lampropeltis triangulum and Lampropeltis gentilis) using genome-scale data to better understand species diversification. Results from artificial neural networks show that a mix of a strong biogeographic barrier, environmental changes, and physical space has affected genetic structure in these taxa. These results underscore conspicuous environmental changes that occur as the sister taxa L. triangulum and L. gentilis diverged near the Great Plains into the forested regions of the Eastern Nearctic. This area has been recognized as a region for turnover for many vertebrate species, but as we show here the contemporary boundary does not isolate these sister species. These two species likely formed in the mid-Pleistocene and have remained partially reproductively isolated over much of this time, showing differential introgression of loci. We also demonstrate that when L. triangulum and L. gentilis are each in contact with the much older L. elapsoides, some limited gene flow has occurred. Given the strong agreement between nuclear and mtDNA genomes, along with estimates of ecological niche, we suggest that all three lineages should continue to be recognized as unique species. Furthermore, this work emphasizes the importance of considering complex modes of divergence and differential allelic introgression over a complex landscape when testing mechanisms of speciation. [Cline; delimitation; Eastern Nearctic; Great Plains; hybrids; introgression; speciation.]

中文翻译:

近北奶蛇( Lampropeltis triangulum 复合体)的生态分歧和基因流动历史

许多对大范围物种的系统地理学研究发现,遗传地理结构与栖息地变化和阻止或减少基因流动的物理障碍有关。这些与地理空间、当代和历史气候以及生物地理障碍的相互作用对当代人口遗传结构和物种形成过程具有复杂的影响。虽然生物地理屏​​障的异域物种形成被认为是产生物种的主要机制,但最近已经表明,旁域的分歧模式可能同样甚至更常见。借助基因组数据和更好的建模能力,我们可以更清楚地定义与生物地理学和谱系间迁移有关的物种形成原因、杂交区相对于亲本谱系生态的位置、和分类群之间基因的差异渗入。在这里,我们使用基因组规模数据检查了三种近北乳蛇(Lampropeltis elapsoides、Lampropeltis triangulum 和 Lampropeltis gentilis)的起源,以更好地了解物种多样化。人工神经网络的结果表明,强大的生物地理屏​​障、环境变化和物理空间的混合影响了这些分类群的遗传结构。这些结果强调了随着姐妹分类群 L. triangulum 和 L. gentilis 在大平原附近分流到近东地区的森林地区而发生的显着环境变化。该地区已被公认为许多脊椎动物物种的周转区域,但正如我们在这里展示的那样,当代边界并未隔离这些姐妹物种。这两个物种可能形成于更新世中期,并且在这段时间的大部分时间里保持部分生殖隔离,显示出基因座的不同渗入。我们还证明,当三角乳杆菌和 L. gentilis 都与更古老的 L. elapsoides 接触时,会发生一些有限的基因流动。鉴于核基因组和 mtDNA 基因组之间的强烈一致性,以及对生态位的估计,我们建议所有三个谱系都应继续被视为独特的物种。此外,这项工作强调了在测试物种形成机制时考虑复杂景观中复杂的分歧模式和差异等位基因渗入的重要性。[克莱恩;划界; 近东; 大平原; 杂种; 基因渗入;物种形成。] triangulum 和 L. gentilis 都与更古老的 L. elapsoides 接触,发生了一些有限的基因流动。鉴于核基因组和 mtDNA 基因组之间的强烈一致性,以及对生态位的估计,我们建议所有三个谱系都应继续被视为独特的物种。此外,这项工作强调了在测试物种形成机制时考虑复杂景观中复杂的分歧模式和差异等位基因渗入的重要性。[克莱恩;划界; 近东; 大平原; 杂种; 基因渗入;物种形成。] triangulum 和 L. gentilis 都与更古老的 L. elapsoides 接触,发生了一些有限的基因流动。鉴于核基因组和 mtDNA 基因组之间的强烈一致性,以及对生态位的估计,我们建议所有三个谱系都应继续被视为独特的物种。此外,这项工作强调了在测试物种形成机制时考虑复杂景观中复杂的分歧模式和差异等位基因渗入的重要性。[克莱恩;划界; 近东; 大平原; 杂种; 基因渗入;物种形成。] 我们建议所有三个谱系都应继续被视为独特的物种。此外,这项工作强调了在测试物种形成机制时考虑复杂景观中复杂的分歧模式和差异等位基因渗入的重要性。[克莱恩;划界; 近东; 大平原; 杂种; 基因渗入;物种形成。] 我们建议所有三个谱系都应继续被视为独特的物种。此外,这项工作强调了在测试物种形成机制时考虑复杂景观中复杂的分歧模式和差异等位基因渗入的重要性。[克莱恩;划界; 近东; 大平原; 杂种; 基因渗入;物种形成。]
更新日期:2021-11-17
down
wechat
bug