Bird migration is a seasonal movement between breeding and wintering grounds.Opinions are widely divided on the reasons for this movement.According to biological data including:geographic distribution,reproductive phy...Bird migration is a seasonal movement between breeding and wintering grounds.Opinions are widely divided on the reasons for this movement.According to biological data including:geographic distribution,reproductive physiology,comparison of breeding and wintering habitats,geological data including Qinghai Tibetan Plateau uplift and Quatemary Period glaciation,it is inferred that bird migration is a survival mechanism,and that migration originated on the breeding grounds.展开更多
Based on the concepts of species and speciation,the speciation of Black necked Grane(Grus nigricollis) was discussed using bio geographic principles and some evidences suggest that Black necked Grane had a close re...Based on the concepts of species and speciation,the speciation of Black necked Grane(Grus nigricollis) was discussed using bio geographic principles and some evidences suggest that Black necked Grane had a close relationship with Red crowned Crane(Grus japonensis).The Qinghai Tibetan Plateau uplift may be the most important factor in allopatric speciation for Black necked Crane.展开更多
文摘Bird migration is a seasonal movement between breeding and wintering grounds.Opinions are widely divided on the reasons for this movement.According to biological data including:geographic distribution,reproductive physiology,comparison of breeding and wintering habitats,geological data including Qinghai Tibetan Plateau uplift and Quatemary Period glaciation,it is inferred that bird migration is a survival mechanism,and that migration originated on the breeding grounds.
文摘Based on the concepts of species and speciation,the speciation of Black necked Grane(Grus nigricollis) was discussed using bio geographic principles and some evidences suggest that Black necked Grane had a close relationship with Red crowned Crane(Grus japonensis).The Qinghai Tibetan Plateau uplift may be the most important factor in allopatric speciation for Black necked Crane.