Abstract Tropical mountains are cradles of biodiversity and endemism. Sundaland, tropical Southeast Asia, hosts 3 species of Rattus endemic to elevations above 2000 m with an apparent convergence in external morphology: Rattus korinchi and R. hoogerwerfi from Sumatra, and R. baluensis from Borneo. A fourth one, R. tiomanicus, is restricted to lowland elevations across the whole region. The origins of these endemics are little known due to the absence of a robust phylogenetic framework. We use complete mitochondrial genomes from the 3 high altitude Rattus, and several related species to determine their relationships, date divergences, reconstruct their history of colonization, and test for selection on the mitochondrial DNA. We show that mountain colonization happened independently in Borneo (<390 Kya) and Sumatra (~1.38 Mya), likely from lowland lineages. The origin of the Bornean endemic R. baluensis is very recent and its genetic diversity is nested within the diversity of R. tiomanicus. We found weak evidence of positive selection in the high-elevation lineages and attributed the greater nonsynonymous mutations on these branches (specially R. baluensis) to lesser purifying selection having acted on the terminal branches in the phylogeny.

中文翻译：

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有丝分裂基因组揭示了在巽他兰的 Rattus 对山脉的多次定植

摘要 热带山脉是生物多样性和特有现象的摇篮。巽他兰是东南亚热带地区，栖息着 3 种海拔超过 2000 米且外部形态明显趋同的地方性大鼠：来自苏门答腊的 Rattus korinchi 和 R. hoogerwerfi，以及来自婆罗洲的 R. baluensis。第四个，R. tiomanicus，仅限于整个地区的低地海拔。由于缺乏强大的系统发育框架，这些地方病的起源鲜为人知。我们使用来自 3 只高海拔大鼠和几个相关物种的完整线粒体基因组来确定它们的关系、日期差异、重建它们的殖民历史，并测试线粒体 DNA 的选择。我们表明山地殖民在婆罗洲（<390 Kya）和苏门答腊（~1.38 Mya）独立发生，可能来自低地血统。婆罗洲特有的 R. baluensis 起源于最近，其遗传多样性嵌套在 R. tiomanicus 的多样性中。我们在高海拔谱系中发现了阳性选择的弱证据，并将这些分支（特别是 R. baluensis）上较大的非同义突变归因于对系统发育末端分支起作用的较少纯化选择。