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Molecular phylogeny and biogeography of the Qinghai-Tibet Plateau endemic Nannoglottis (Asteraceae)
文献类型：期刊论文
| 作者 | Liu, JQ; Gao, TG; Chen, ZD; Lu, AM |
| 刊名 | molecular phylogenetics and evolution
 |
| 出版日期 | 2002-06-01 |
| 卷号 | 23期号:3页码:307-325 |
| 关键词 | Nannoglottis Astereae Asteraceae trnL-F ndhF ITS the Qinghai-Tibet Plateau endemics phylogeny historical biogeography |
| 合作状况 | 其它 |
| 中文摘要 | all taxa endemic to the qinghai-tibet plateau are hypothesized to have originated in situ or from immediately adjacent areas because of the relatively recent formation of the plateau since the pliocene, followed by the large-scaled biota extinction and recession caused by the quaternary ice sheet. however, identification of specific progenitors remains difficult for some endemics, especially some endemic genera. nannoglottis, with about eight species endemic to this region, is one such genus. past taxonomic treatments have suggested its relationships with four different tribes of asteraceae. we intend to identify the closest relatives of nannoglottis by evaluating the level of monophyly, tribal delimitation, and systematic position of the genus by using molecular data from ndhf gene, trnl-f, and its region sequences. we find that all sampled species of nannoglottis are a well-defined monophyly. this supports all recent taxonomic treatments of nannoglottis, in which all sampled species were placed in one broadly re-circumscribed genus. nannoglottis is most closely related to the astereae, but stands as an isolated genus as the first diverging lineage of the tribe, without close relatives. a tentative relationship was suggested for nannoglottis and the next lineage of the tribe was based on the its topology, the "basal group," which consists of seven genera from the southern hemisphere. such a relationship is supported by some commonly shared plesiomorphic morphological characters. despite the very early divergence of nannoglottis in the astereae, the tribe must be regarded to have its origin in southern hemisphere rather than in asia, because based on all morphological, molecular, biogeographical, and fossil data, the asteraceae and its major lineages (tribes) are supposed to have originated in the former area. long-distance dispersal using southeast asia as a steppingstone from southern hemisphere to the qinghai-tibet plateau is the most likely explanation for this unusual biogeographic link of nannoglottis. the 23-32-million-year divergence time between nannoglottis and the other astereae estimated by dna sequences predated the formation of the plateau. this estimation is further favored by the fossil record of the asteraceae and the possible time of origin of the astereae. nannoglottis seems to have reached the qinghai-tibet area in the oligocene-eocene and then re-diversified with the uplift of the plateau. the molecular infragenetic phylogeny of the genus identifies two distinct clades, which reject the earlier infrageneric classification based on the arrangement of the involucral bracts and the length of the ligules, but agree well with the habits and ecological preferences of its current species. the "alpine shrub" vs. "coniferous forest" divergence within nannoglottis was estimated at about 3.4 million years ago when the plateau began its first large-scale uplifting and the coniferous vegetation began to appear. most of the current species at the "coniferous forest" clade of the genus are estimated to have originated from 1.02 to 1.94 million years ago, when the second and third uprisings of the plateau occurred, the climate oscillated and the habitats were strongly changed. the assumed evolution, speciation diversity, and radiation of nannoglottis based on molecular phylogeny and divergence times agree well with the known geological and paleobotanical histories of the qinghai-tibet plateau. (c) 2002 elsevier science (usa). all rights reserved. |
| 英文摘要 | all taxa endemic to the qinghai-tibet plateau are hypothesized to have originated in situ or from immediately adjacent areas because of the relatively recent formation of the plateau since the pliocene, followed by the large-scaled biota extinction and recession caused by the quaternary ice sheet. however, identification of specific progenitors remains difficult for some endemics, especially some endemic genera. nannoglottis, with about eight species endemic to this region, is one such genus. past taxonomic treatments have suggested its relationships with four different tribes of asteraceae. we intend to identify the closest relatives of nannoglottis by evaluating the level of monophyly, tribal delimitation, and systematic position of the genus by using molecular data from ndhf gene, trnl-f, and its region sequences. we find that all sampled species of nannoglottis are a well-defined monophyly. this supports all recent taxonomic treatments of nannoglottis, in which all sampled species were placed in one broadly re-circumscribed genus. nannoglottis is most closely related to the astereae, but stands as an isolated genus as the first diverging lineage of the tribe, without close relatives. a tentative relationship was suggested for nannoglottis and the next lineage of the tribe was based on the its topology, the "basal group," which consists of seven genera from the southern hemisphere. such a relationship is supported by some commonly shared plesiomorphic morphological characters. despite the very early divergence of nannoglottis in the astereae, the tribe must be regarded to have its origin in southern hemisphere rather than in asia, because based on all morphological, molecular, biogeographical, and fossil data, the asteraceae and its major lineages (tribes) are supposed to have originated in the former area. long-distance dispersal using southeast asia as a steppingstone from southern hemisphere to the qinghai-tibet plateau is the most likely explanation for this unusual biogeographic link of nannoglottis. the 23-32-million-year divergence time between nannoglottis and the other astereae estimated by dna sequences predated the formation of the plateau. this estimation is further favored by the fossil record of the asteraceae and the possible time of origin of the astereae. nannoglottis seems to have reached the qinghai-tibet area in the oligocene-eocene and then re-diversified with the uplift of the plateau. the molecular infragenetic phylogeny of the genus identifies two distinct clades, which reject the earlier infrageneric classification based on the arrangement of the involucral bracts and the length of the ligules, but agree well with the habits and ecological preferences of its current species. the "alpine shrub" vs. "coniferous forest" divergence within nannoglottis was estimated at about 3.4 million years ago when the plateau began its first large-scale uplifting and the coniferous vegetation began to appear. most of the current species at the "coniferous forest" clade of the genus are estimated to have originated from 1.02 to 1.94 million years ago, when the second and third uprisings of the plateau occurred, the climate oscillated and the habitats were strongly changed. the assumed evolution, speciation diversity, and radiation of nannoglottis based on molecular phylogeny and divergence times agree well with the known geological and paleobotanical histories of the qinghai-tibet plateau. (c) 2002 elsevier science (usa). all rights reserved. |
| WOS标题词 | science & technology ; life sciences & biomedicine |
| 学科主题 | 生物化学 ; 分子生物学 |
| 类目[WOS] | biochemistry & molecular biology ; evolutionary biology ; genetics & heredity |
| 研究领域[WOS] | biochemistry & molecular biology ; evolutionary biology ; genetics & heredity |
| 关键词[WOS] | nuclear ribosomal dna ; noncoding chloroplast sequences ; astereae asteraceae ; gene ndhf ; evolution ; origin ; senecioneae ; alliance ; islands ; anthemideae |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000177028500002 |
| 公开日期 | 2009-12-10 |
| 源URL | [http://ir.nwipb.ac.cn/handle/363003/1417]  |
| 专题 | 西北高原生物研究所_中国科学院西北高原生物研究所 |
| 作者单位 | 1.Chinese Acad Sci, NW Plateau Inst Biol, Xining 81001, Qinghai, Peoples R China 2.Chinese Acad Sci, Inst Bot, Lab Systemat & Evolutionary Bot, Beijing 100093, Peoples R China |
| 推荐引用方式 GB/T 7714 | Liu, JQ,Gao, TG,Chen, ZD,et al. Molecular phylogeny and biogeography of the Qinghai-Tibet Plateau endemic Nannoglottis (Asteraceae)[J]. molecular phylogenetics and evolution,2002,23(3):307-325. |
| APA | Liu, JQ,Gao, TG,Chen, ZD,&Lu, AM.(2002).Molecular phylogeny and biogeography of the Qinghai-Tibet Plateau endemic Nannoglottis (Asteraceae).molecular phylogenetics and evolution,23(3),307-325. |
| MLA | Liu, JQ,et al."Molecular phylogeny and biogeography of the Qinghai-Tibet Plateau endemic Nannoglottis (Asteraceae)".molecular phylogenetics and evolution 23.3(2002):307-325. |
入库方式： OAI收割
来源：西北高原生物研究所
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