山东社鼠的物种分类地位与系统演化起源

山东社鼠(Niviventer confucianus sacer)一直被作为社鼠的一个亚种，但申请人团队的先期研究与其他学者的报道发现，它在染色体核型和形态学上均与社鼠存在明显不同，在分子系统发育树上与分布于越南的马来白腹鼠(N. bukit)的亲缘关系最近而不被包含在社鼠（种团）支系内。这说明山东社鼠的物种地位并非社鼠的亚种，且从物种扩散与分化上无法解释它与数千公里之外的马来白腹鼠亲缘关系最近的现象。申请者认为，山东社鼠在系统发育树上的这种千里“跳跃”到山东地区的谜点，是由于山东相邻区域的社鼠古代反复渐渗杂交造成的系统发育树假象，也是由于线粒体基因的突变特点与核基因信息位点量严重不足造成。申请人拟通过采用RAD-seq技术获得充分的核基因SNP数据集，与线粒体基因、核型与形态学数据相结合，彻底解决山东社鼠的系统发育关系、独立物种地位以及系统地理学来源的“跳跃”之谜。

The Niviventer confucianus sacer, which has always been considered as a subspecies of N. confucianus, has significant differentiation with N. confucianus in chromosome karyotype and morphologies in our preliminary study and the recent reports, especially, molecular phylogeny analyses demonstrated that N. c. sacer had a sister relationship with N. bukit distributed Vietnam where is too distant from Shandong region, but not included in the leanages of N. confucianus. It indicates that the so-called “N. c. sacer” is not a subspecies of N. confucianus but a distinct species. More interestingly, its phylogenetic sister relationship with N. bukit which is too far in geographical distance to Shandong area, implying a mystery of “long jump” in its dispersion. We consider this abnormal phenomenon is due to the ancient introgressive hybridizations among geographic groups of N. confucianus, and also due to the permutation peculiarity of mtDNA and too few effective mutation sites of nuclear genes used in the phylogenetic analyses. We intend to employ RAD-seq DNA and mtDNA genes as well as karyotype and morphologies data to thoroughly dissolve the species delimitation, phylogeny and phylogenetics of the so-called “N. c. sacer”, and propose a new insight into studies of phylogeny and phylogeography by solving this “long-jump” puzzle.