Amphitropical disjunctions in New World Menthinae: Three Pliocene dispersals to South America following late Miocene dispersal to North America from the Old World
Amphitropical disjunctions in New World Menthinae: Three Pliocene dispersals to South America following late Miocene dispersal to North America from the Old World
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DOI：
10.3732/ajb.1700225
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发表时间：
2017-11-01
影响因子：
3
通讯作者：
Sytsma, Kenneth J.
中科院分区：
文献类型：
--
作者：
Drew, Bryan T.;Liu, Sitong;Sytsma, Kenneth J.
研究前提：薄荷亚族(Lamiaceae)有35属750种，是薄荷科中规模最大、经济最重要的亚族之一。薄荷亚科的大多数属仅见于新大陆，在那里该群几乎连续地分布在从北美洲温带到南美洲南部的范围内。在这项研究中，我们探索了薄荷属中两性分离的存在、时间和起源。方法：我们的分析基于由89个分类群和核核糖体DNA标记ITS和ETS组成的数据集。在最大似然法和贝叶斯准则下确定系统发育关系，用程序BEAST估计分化时间，用BioGeoBEARS估计祖先范围。结果：推断出约10.6 Ma的北大西洋大陆桥从欧亚西部到北美的迁徙事件。新世界薄荷亚科在北美迅速蔓延，然后蔓延到中美洲和南美洲。几个大的物种属与核rDNA不是单系进化，这一发现与之前的叶绿体DNA结果相一致。其中一个南美东南部分支包括一个南美东南部分支，其中一个包括南美东南部的几个属。结论：虽然北美和南美洲都有3个新世界薄荷亚属，但没有一个表现出营养分离。然而，三个分支都表现出两栖分离，都可以追溯到上新世早期，并且都涉及从北美东南部到南美洲东南部或西南部的跳跃扩散。
PREMISE OF THE STUDY: The subtribe Menthinae (Lamiaceae), with 35 genera and 750 species, is among the largest and most economically important subtribes within the mint family. Most genera of Menthinae are found exclusively in the New World, where the group has a virtually continuous distribution ranging from temperate North America to southern South America. In this study, we explored the presence, timing, and origin of amphitropical disjuncts within Menthinae.METHODS: Our analyses were based on a data set consisting of 89 taxa and the nuclear ribosomal DNA markers ITS and ETS. Phylogenetic relationships were determined under maximum likelihood and Bayesian criteria, divergence times were estimated with the program BEAST, and ancestral range estimated with BioGeoBEARS.KEY RESULTS: A North Atlantic Land Bridge migration event at about 10.6 Ma is inferred from western Eurasia to North America. New World Menthinae spread rapidly across North America, and then into Central and South America. Several of the large speciose genera are not monophyletic with nuclear rDNA, a finding mirrored with previous chloroplast DNA results. Three amphitropical disjunctions involving North and southern South America clades, one including a southeastern South American clade with several genera, were inferred to have occurred within the past 5 Myr.CONCLUSIONS: Although three New World Menthinae genera occur in both North and South America, none exhibit an amphitropical disjunction. However, three clades exhibit amphitropical disjunctions, all dating to the early Pliocene, and all involve jump dispersals to either southeastern or southwestern South America from southeastern North America.