【作者】 龚一峰；

【导师】 王金富；

【作者基本信息】 石河子大学 ， 动物遗传育种与繁殖， 2006， 硕士

【摘要】 用雪鸡属(Tetraogallus)及其5个近缘种属的线粒体细胞色素b(mtDNA cyto-b)基因并通过邻接(NJ)法构建了它们的系统进化树,以马鸡属(Crossoptilon)为外群(Out group),研究了雪鸡属在近缘属中的进化位置和关系,以及它的进化历程。结果表明:日本鹌鹑(Coturnix Japonica)和蓝胸鹌鹑(Coturnix Chinensis)的BP(bootstrap percentage)值为92%,阿尔泰雪鸡(T.altaicus)和喜玛拉雅雪鸡(T.himalayensis)的BP值为100%,(阿尔泰雪鸡、喜玛拉雅雪鸡)和藏雪鸡(T.tibetanus)的BP值为100%;石鸡属(Alectoris)、鹌鹑属(Coturnix)、雪鸡属和勺鸡属(Pucrasia)组成一个单系群;石鸡属和鹌鹑属的共同祖先与雪鸡属的祖先是姐妹群。各属总的平均遗传距离为0.112,雪鸡属的平均遗传距离为0.042。雪鸡属各种间的遗传距离依次为:阿尔泰雪鸡到喜玛拉雅雪鸡为0.012,喜玛拉雅雪鸡到藏雪鸡为0.067,阿尔泰雪鸡到藏雪鸡为0.068。结合雪鸡属各品种间的遗传距离、分布特征和形态特征,推测藏雪鸡很可能是这三种雪鸡品种中最为原始的品种,并且在1.7百万年前,栖息在新疆西南部和西藏中西部的体色较深的藏雪鸡亚种tibetanus向西进入喜玛拉雅山区,逐步演变成喜玛拉雅雪鸡。后来,常出现在阿尔泰山区和东昆仑山的体色较浅的喜玛拉雅雪鸡亚种koslowi进化成了阿尔泰雪鸡。里海雪鸡(T.caspius)和高加索雪鸡(T.caucasicus)的采样受地域限制,所以本课题未涉及它们的系统进化地位。因此,要完全明白所有雪鸡品种的分类地位则需要更为进一步的调查和研究。但同时,我们能根据雪鸡属成员的分布范围和形态特征给出这样一个假说,藏雪鸡是雪鸡属所有成员中最为原始的品种,高加索雪鸡起源于阿尔泰雪鸡,里海雪鸡则起源于喜玛拉雅雪鸡。更多还原

【Abstract】 A phylogenetic tree of Neighbor-joining (NJ) distance matrix calculated with Kimura 2-parameter was performed and Crossoptilon auritum was used as outgroup to study the phylogenetic position of the genus Tetraogallus, to understand the phylogenetic relationships, and to infer the evolutionary process of Tetraogallus. Numbers near the branches were bootstrap probability (BP) values coming from 1000 replications. Some bootstrap probability values were 92% (Coturnix chinensis/ Coturnix japonica), 100% (Tetraogallus altaicus/ Tetraogallus himalayensis), and 100% ((Tetraogallus altaicus/ Tetraogallus himalayensis)/ Tetraogallus tibetanus). The overall average distance was 0.112, and average genetic distance among Tetralgallus was 0.042. The genera Alectoris, Coturnix, Tetrao-gallus and Pucrasia formed a monophyletic group. The two genera, Alectoris and Coturnix, should have a common ancestor, which was the sister taxon of the ancestor of the genus Tetraogallus.The interspecific genetic distances of the genus Tetraogallus were 0.012 (T.altaicus vs T. himalayensis), 0.067 (T. himalayensis vs T.tibetanus) and 0.068 (T.altaicus vs T.tibetanus) respectively. It was possible that Tibetan snow cocks were the primitive species among the three breeds, and, 1.7 million years ago, that one subspecies holding a deep body color, tibetanus distributing in the southwest of xinjiang and the Midwest of Tibet, of Tibetan snow cocks migrated towards the West and entered the Himalayan Mountain to become the present Himalayan snow cocks. Later, another subspecies of Himalayan snow cocks, koslowi, owning a light body color, often emerge in the Altai Mountain and the east of Kunlun Mountain to evolve into Altai snow cocks according to the witness of geographical distribution pattern and morphological character combing the genetic distances among them.As to Caspian snowcocks and Caucasian snowcocks, we consider our sample of Tetraogallus taxa insufficient to resolve this issue, and solid conclusions on the status of the total Tetraogallus awaited inclusion of additional related taxa, and require further investigation. But, we can give a hypothesis that, according to the geographical distribution range and morphological character, Tibetan snowcocks may be the most primitive breed among the five snowcock species, and Caucasian snowcock derived from Altai snowcocks. As to Caspian snowcocks, they might derive from Himalayan snowcocks. Of course, this hypothesis needs further investigation and study.更多还原