Evolutionary history of the subnival flora of the Himalaya-Hengduan Mountains: first insights from comparative phylogeography of four perennial herbs
Evolutionary history of the subnival flora of the Himalaya-Hengduan Mountains: first insights from comparative phylogeography of four perennial herbs
复制标题
喜马拉雅-横断山冰下植物区系的进化史：四种多年生草本植物比较系统发育地理学的初步见解
DOI：
10.1111/jbi.12610
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发表时间：
2016
影响因子：
3.9
通讯作者：
Sun Hang
中科院分区：
文献类型：
--
作者：
Luo Dong;Yue Ji-Pei;Sun Wen-Guang;Xu Bo;Li Zhi-Min;Comes Hans Peter;Sun Hang
目的喜马拉雅-横断山（HHM）生物多样性热点地区，包括中国西南部的“天空岛”，在亚高山（大多数海拔超过4300米）上拥有特殊的植物多样性和特有性。这项研究是第一次使用比较的地理学框架来深入了解这种高度分散的亚坚定不移植物群的时间起源，以及形成其遗传结构的历史因素，例如四种多年生草本植物。我们进行了AMOVA和失配分布分析，以评估分子结构，多样性和人口历史的关系，目前和末次冰期的分布，使用生态位模型（ENM）。时间校准的系统发育重建的cpDNA数据被用来推断物种特定的茎和冠ages.ResultsOur时间估计表明，这些物种起源于上新世晚期或早至中更新世，而他们的发病多样化一般福尔斯到中更新世。所有四个物种都表现出岛状的种群遗传结构，它们都显示出基于cpDNA的最近种群增长和/或空间扩张的特征。相反，ENM表明，在末次冰期/冰后期循环中，物种的大规模分布保持相当稳定。主要结论四种亚百孔虫的时间起源可能与该地区的构造变化有关，而它们在“Naynayxungla冰期”（0.72-0.50 Ma）期间几乎同时发生的多样化可能反映了气候引起的栖息地破碎化导致的初始种群分化。尽管有相当稳定的分布历史，但地理种群隔离和局部范围的扩张/收缩可能导致了末次冰期/后冰期循环中显着的遗传结构和分化。总体而言，目前的研究结果是强烈的共享的进化历史和subbendredplants从“天空岛系统”的HHM地区的地理结构之间的指示。
AimThe Himalaya‐Hengduan Mountain (HHM) biodiversity hotspot including the ‘sky islands’ of Southwest China harbour exceptional plant diversity and endemicity at subnival summits (most of them exceeding 4300 m a.s.l.). This study is the first using a comparative phylogeographical framework to gain insights into the temporal origin of this highly fragmented subnival flora, and the historical factors shaping its genetic architecture as exemplified by four perennial herbs.LocationHimalaya‐Hengduan Mountains, China.MethodsBased on nuclear and/or chloroplast (cp) DNA sequences for each of the four studied species, we performed AMOVA and mismatch distributional analyses to assess molecular structure, diversity and demographic history in relation to current and last glacial distributions using ecological niche modelling (ENM). Time‐calibrated phylogenetic reconstructions of cpDNA data were used to infer species‐specific stem and crown ages.ResultsOur time estimates suggest that these species originated during the Late Pliocene or early‐to‐mid Pleistocene, whereas their onset of diversification generally falls into the mid‐Pleistocene. All four species exhibited island‐like population genetic structures, with all of them showing signatures of recent population growth and/or spatial expansion based on cpDNA. By contrast, ENM indicated that species broad‐scale distributions remained fairly stable over the last glacial/post‐glacial cycle.Main conclusionsThe temporal origin of the four subnival HHM species is likely associated with tectonic changes in the region, while their near‐simultaneous onset of diversification during the ‘Naynayxungla Glaciation’ (0.72–0.50 Ma) could reflect initial population divergence through climate‐induced habitat fragmentation. Despite a rather stable distributional history, geographical population isolation and localized range expansion/contractions likely resulted in significant genetic structure and differentiation over the last glacial/post‐glacial cycle. Overall, the present results are strongly indicative of shared evolutionary histories and phylogeographical structures among subnival plants from the ‘sky island system’ of the HHM region.