青藏高原东缘-东北缘蝉科昆虫多样性、物种分化及谱系地理研究

蝉科昆虫若虫长期在地下固定生活，成虫寿命短、飞行力弱，难以扩散，是研究物种形成和生物地理的理想模式生物。青藏高原东缘和东北缘是古北界与东洋界的重要交汇地带，但高原隆升和气候变化等对这里很多动物的起源、扩散、多样性分化及适应的影响仍是谜团；该地区的蝉科昆虫多样性一直缺乏系统研究，部分单元的系统地位更长期存疑，一直阻碍印度次大陆与古北界相邻地区的蝉科昆虫多样性廓清和系统发育重建。本项目拟结合前期研究，综合采用比较形态学、生物声学、分子系统学和谱系地理学研究方法，廓清该区域蝉科昆虫的多样性、区系格局和存疑类群的系统地位，重点对不同模式生境（高山–亚高山、低山–峡谷–丘陵）的代表类群进行表型、鸣声和遗传分化及谱系地理研究，寻绎重大自然历史事件对其多样性分化和谱系地理结构形成的影响，检验地理隔离和自然选择在谱系分化中的作用，为青藏高原边缘地带特殊环境下生物多样性的形成、维持和丧失机制研究提供新信息。

Insects of the family Cicadidae (Insecta: Hemiptera) are excellent subjects for bio-geographical studies because of their low dispersal ability caused by the generally long, subterranean pre-adult stage, short adult lifespan and their much less flying capability than other insects. Areas along the eastern and north-eastern margins of Qinghai-Tibetan Plateau (QTP) are located in the transition region between the Parlaerartic and Oriental Regions, where the landform and plant community are remarkably complicated. However, effects of uplift of the Plateau and climate changes on the origin, dispersal, diversification and adaptation of many animal taxa remain unravelled. Up to date, studies of biodiversity and fauna on cicadas occurring there are extremely limited, and the systematic status of a few taxa of Cicadidae that mainly distributed there remains problematic, which hinder studies to clarify the cicada fauna and biodiversity along the transitional zone between the Parlaerartic and Oriental Regions and to reconstruct the phylogeny of related taxa. For the proposed project we are taking our work further to investigate the cicada biodiversity and fauna as well as the systematic status of related taxa by comprehensively using methods of comparative morphology, bioacoustics, molecular systematics, and phylogeograpy, etc. In particular, we will focus on the morphological differentiation, acoustic-signal diversification, genetic differentiation and phylogeographic structure of representative species that separately occur in habitats of two distinctly different models, i.e., the alpine–subalpine zones and the low-altitude mountain–canyon–hill zones, which may test the relative effects that geographic isolation and natural selection exact on the lineage differentiation of related taxa, and reveal to what degree the topography and climate change shaped the genetic diversity and diversification. The results will expand our knowledge of the cicada fauna there and provide a more secure and productive framework for research of genetic diversification and the mechanisms of biodiversity formation, maintenance and loss in areas along the eastern and north-eastern margins of QTP.