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shelduck n.sheldrake 的雌性。

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Phylogenetic analysis surports that anseranas should be placed in monotypic family anseranatidae , and the whistling ducks and the white - backed duck should be separated from subfamily anserinae and placed them into family dendrocygnidae . the family anatidae could be classified into two subfamilies , anserinae and anatinae . the results approve that the swans should be put into the tribe cygnini of subfamily anserinae as suggested by livezey ( 1996 , 1997b ) and the shelducks should be placed in the tribe tadornini of subfamily anatinae , therefore , our results do not support sibley and ahlquist ' s ( 1990 ) establishment of the subfamily cygninae and placing the shelducks in the tribe anserini 研究結果表明: 1 )雁形目鳥類12srrna基因有較多的堿基插入和缺失,堿基轉換數高于顛換數; 2 )贊同將鵲鵝( anseranas )置于鵲鵝科( anseranatidae )中,樹鴨( dendrocygna )應從雁亞科( anserinae )中獨立出來設立樹鴨科( dendrocygnidae ) ,白背鴨( thalassornis )隸屬于樹鴨科; 3 )鴨科( anatidae )可分為雁亞科和鴨亞科( anatinae ) 2個亞科,不贊同sibley & ahlquist ( 1990 )設立天鵝亞科( cygninae )及將麻鴨歸入雁族( anserini )的觀點,支持livezey ( 1996a , 1997b )的觀點建議將天鵝類歸為雁亞科天鵝族( cygnini ) ,麻鴨置于鴨亞科下麻鴨族; 4 )在鴨亞科內的系統發生上,潛鴨最早分歧出來,麻鴨、海中文摘要鴨及棲鴨彼此iaj的親緣關系較近;河鴨族為一單系發生群,在系統演化中形成獨立的一支。