马鸡的分类、分布及演化关系的初步探讨

（１）在耳羽簇发达程度，尾羽形状，腓肠肌外支腿膜内的种子骨和第二趾收肌，雄鸡间争偶和占区行为，巢址选择，瓣生雏形态等方面，白马鸡和藏马鸡，蓝马鸡和褐钯鸡分别表现出明显不同的一致性。基于此，我们认为白马鸡和藏马鸡是原始的类型，蓝马鸡和褐马鸡有较近的亲缘关系。（２）青藏高原短暂的隆起历史和相应发生的生态环境的复杂变化，是白马鸡各亚种形态多变而不稳定的主要原因。与白马鸡相比，藏马鸡的体色特化而稳定，结合

A PRELIMINARY INVESTIGATION ON TAXONOMY,DIS-TRIBUTION AND EVOLUTIONARY RELATIONSHIP OF THE EARED PHEASANTS,CROSSOPTILON

(1)It is easy to distinguish C.crossoptilon and C.harmani from C.auritum and C.mantchuricum by shapes of ear tufts and tail,sesamoid in gastrocnemius tendon and adductor digitus secundi,behaviours of fighting for mate and territory between males,nest selection,morphology of newly hatched nestling.Based on these C.crossoptilon and C.harmani are considered more primitive,and there is a closer relative relationship between them than that between C.auritum and C.mantchuricumis .(2)It is likely that the shorter history of rise of Qing Zang plateau and correspondingly its complicated change in ecological environment have been making the subspecies of C.crossoptilon vary greatly on morphology.Comparing with C.crossoptilon ,the body colour of C.harmani is specialized and stable.The development of environment of their distribution areas indicates that C.harmani could have remained more ancestral characteristics.(3)According to the fossil,geographical distribution,ecologically adaptive features along with geological history,a hypothesis has been produced that the speciation of the Eared Pheasants is a process in which their ancestral species specialized and spread from the junction of Sichuan,Yunnan and Tibet towards the north then the east.