西藏雅鲁藏布大峡谷冰期避难所白蚁分子谱系地理学研究

白蚁 谱系地理学 雅鲁藏布大峡谷 冰期避难所 西藏
王建国 2014-01 项目
The climatic oscillation during Quaternary must have important effects on spatial distribution and genetic structure of organisms distributed in the Yarlung Zangbo Grand Canyon (YZGC). However, how the termite species occurred there changed their distribution ranges in response to Quaternary climatic oscillation remains controversial. Here, we conduct a study of the phylogeography of the termite genera Reticulitermes, Nasutitermes and Odontotermes endemic and dominant termite species in the canyon with mtDNA and regions of the nrDNA will be developed as an valuable molecular marker to resolve phylogenetic relationships at different taxonomic levels. Microsatellite markers or short tandem repeats (STRs) are increasingly going to applied to study cryptic speciation in the genus Odontotermes with the samples from YZGC,Indian,Malaysia and East Asia. The genus Nasutitermes would used to refer for sympatric speciation with disruptive selection or parapatric speciation.Phylogeographic and population genetic analyses of the genus Reticulitermes for worldwide spread species R. speratus can provide information about the geographical origins and patterns of introduction and explain the causes and mechanisms by which introduced species have become successful invaders. Wood-feeding cockroaches Cryptocercus cockroaches have appeared to many as ideal models for inference on the early evolution of termites, due to their possible phylogenetic relationship and several shared key attributes in life history. it is considered Cryptocercus the best representative of the ancestral type of phylogenetic outgroup with termites and is thus crucial in delineating relationships among the species of Cryptocercus, and in determining the relationship of the genus to other cockroaches and to termites. However, no fresh material suitable for modern approaches to systematics has been available for all of China.Cryptocercus will be introduced as models for Tibet termite evolution. Glacial refugia theories about the distribution of termites occupying YZGC provide possible clues into the possible mechanisms which have fostered genetic variability and restricted gene flow.The study will provide valuable evidence that the termite species endemic in the YZGC how to speciation and evolution, the results will refer a different pattern how the termite species in the YZGC responded to the climatic changes during the Quaternary.
全球气候的反复变化特别是第四纪冰期对雅鲁藏布大峡谷(YZGC)物种的地理分布及遗传结构产生了重大影响。而该地区白蚁物种的进化历史至今仍存在较多争议。我们采用mtDNA和核糖体ITS等基因组的分子标记,将对雅鲁藏布大峡谷特有白蚁(Isoptera)物种三个属散白蚁属Reticulitermes, 象白蚁属Nasutitermes 土白蚁Odontotermean,进行谱系地理学方面的研究。微卫星标记或STRs拟用于雅鲁藏布、印度和马拉西亚等东南亚地区的土白蚁属标本的物种分化研究。以世界广布种栖北散白蚁R. sepratus为代表的散白蚁属谱系地理学和种群遗传分析, 将为该物种在全世界广泛传播提供信息。以象白蚁属为材料研究同域物种形成,是裂变选择还是近域物种形成机制。食木蜚蠊隐尾蠊属Cryptocercus的分科位置尚未稳定,其与白蚁的亲缘关系亦悬而未决,拟通过隐尾蠊属推测西藏白蚁的进化历史,获得雅鲁藏布大峡白蚁分布相关冰期避难所理论可能线索,为该地区白蚁种类分化与进化提供有价值的证据,揭示雅鲁藏布大峡谷白蚁如何应对第四季冰川。