黑眉长尾山雀(Aegithalos bonvaloti)和银脸长尾山雀(A. fuliginosus)是长尾山雀属内一对近缘种。早期研究发现两种之间具有极小的线粒体遗传距离，在其分布重叠区具有共享的线粒体基因单倍型，且有从银脸长尾山雀向黑眉长尾山雀的单向基因流，推测可能是由于种间杂交，结合选择性清除或遗传漂变共同作用的结果。我们近期发现了杂交带内存在杂交后代，因此推测两种之间目前依然存在种间的基因交换，符合伴随基因流的生态成种模式。为此，本项目重点探讨：两个物种接触带的分布与成因；基因流对其基因组产生的影响以及物种形成相关基因的挖掘与定位等等，旨在进一步探讨近缘种的成种模式和种间遗传关系。本研究将会在探讨基因流对物种的形成和分化的作用机制等研究方面具有重要理论意义。

The Black-browed Tit and the Sooty Tit are two closely related species. Previous studies revealed that the mitochondrial DNA (mtDNA) differentiation was extremely low, with shared haplotypes in the hybrid zone between the two species, and also found that unidirectional mtDNA gene flow from A. fuliginosus to A. bonvaloti, which suggested that historical hybridization, in combination with selective sweep and/or genetic drift might be the main causes of this patterns. Our recent preliminary study revealed hybrid individuals from the hybrid zone implying ongoing gene exchange between the two species, which suggests an ecological speciation pattern with gene flow hypothesis. This project aims to explore the speciation modes and interspecific genetic relationships of the two closely related species. The project therefore will focus on: distribution and forming of the hybrid zone between the two species; the impacts of gene flow on the genomes, with digging and identifying the potential speciation related genes. Our research would highlight the theoretical importance in ecological speciation and species differentiation with gene flow.