Evidence for multiple founding lineages and genetic admixture in the evolution of species within an oceanic island weevil (Coleoptera, Curculionidae) super-radiation
Evidence for multiple founding lineages and genetic admixture in the evolution of species within an oceanic island weevil (Coleoptera, Curculionidae) super-radiation
复制标题
DOI：
10.1111/jbi.12606
复制
发表时间：
2016-01-01
影响因子：
3.9
通讯作者：
Emerson, Brent C.
中科院分区：
文献类型：
--
作者：
Faria, Christiana M. A.;Machado, Antonio;Emerson, Brent C.
目的推测神秘的金丝雀岛象鼻虫辐射中9个物种密切相关的复合体的定殖史和物种形成史。利用分子测年和岛屿提供的时空背景，我们评估了不同岛屿物种之间共同遗传变异起源的不完全谱系分类和基因流动的可能解释。加那利群岛(大加那利岛、特内里费岛、拉帕尔马岛和埃尔耶罗岛)。利用线粒体(COII)和核(ITS2)序列的系统发育分析和分子测年技术推测该群在该群岛的起源及其殖民和分化的历史。一个意想不到的结果是，线粒体DNA显示，拉帕尔马和埃尔耶罗上的每个单一物种都是来自不止一个来源岛屿的不止一次殖民事件的产物。主要结论这两个基因树呈现出非常不同的拓扑结构，只需要相当简单的定殖史来解释核基因关系的模式，而mtDNA基因树则蕴含着复杂得多的定殖史。排除了对不完全谱系分类的解释，并推测了涉及遗传混合的细毛藻复合体的定殖史和物种形成史。
Aim To infer colonization and speciation history for a closely related complex of nine species within the enigmatic Canary Island Laparocerus weevil radiation of 128 species. Using molecular dating and the spatial and temporal context that islands provide, we evaluate the possible explanations of incomplete lineage sorting and gene flow for the origin of shared genetic variation among species from different islands.Location Canary Islands (Gran Canaria, Tenerife, La Palma and El Hierro).Methods We collected a total of 173 specimens from 37 sites distributed across the four islands. Phylogenetic analyses of mitochondrial (COII) and nuclear (ITS2) sequence data and molecular dating techniques were used to infer the origin of the group in the archipelago and their history of colonization and differentiation.Results Gran Canaria appeared to be the geographical origin of the complex. An unexpected result was that mtDNA revealed each of the single species on La Palma and El Hierro to be the product of more than one colonization event from more than one source island. In both cases nuclear ITS2 data revealed these multiple colonizations to have been followed by admixture.Main conclusions The two gene trees present very different topologies, with a rather simple colonization history required to explain the pattern of nuclear gene relationships, while the mtDNA gene tree implicates a much more complex history of colonization. Explanations of incomplete lineage sorting are ruled out and a history of colonization and speciation for the L. tessellatus complex involving genetic admixture is inferred.