关键词: Cyt b, ZFY;系统进化, 偏雄性扩散, 四川亚种

Abstract: To explore the phylogenetic relationships among tribe caprini and the species validity of Pseudois schaeferi in Pseudois,the total sequence of mitochondrial Cyt b (1140 bp)and partial sequence of the nuclear gene ZFY (612 bp) were detected in 226 fecal DNA samples of Pseudois nayaur and Pseudois schaeferi living above and below the forest line, respectively,in the valley area of the Jinsha River. These sequences were compared to the homologous DNA sequences of the tribe caprini retrieved from GenBank,then we reconstructed phylogenetic tree using maximum parsimony,maximum likelihood methods,primarily to investigate the phylogenetic relationship among these species based on obtained topological structure. The results showed that the kinship was the farthest between Ovis and other genera including Capra,Pseudois and Hemitragus. Hemitragus jelahicus was the nearest relative between Pseudois and Capra. Pseudois nayaur and the Pseudois schaeferi living in the valley area of Jinsha River are classified as the same branches as the Pseudois nayaur living in Inner Mongolia,Qinghai and Sichuan. They share the same haplotypes of Cyt b and ZFY with some Pseudois nayaur and
Pseudois schaeferi living in the valley area of Jinsha River. The climatic events in history might lead to the intermigration of Pseudois nayaur and Pseudois schaeferi living in the valley area of Jinsha River,and male-biased dispersal promoted the gene exchanges among different geographic populations. Thus,Pseudois schaeferi should not be classified as an independent species,we advise that Pseudois nayaur and Pseudois schaeferi living in the valley area of Jinsha River be classified as Pseudois nayaur szechuanensis. The dwarf Pseudois nayaur should be managed independently due to the distinctive evolutionary characteristics in morphology and ecology.

Key words: Cyt b, Male-biased dispersal, Phylogeny, Pseudois nayaur szechuanensis, ZFY