ブラックバード (Icterinae) の種間繁殖寄生症: 系統遺伝学的視点
1Department of Zoology, Field Museum of Natural History, Chicago, IL 60605-2496.
Science (New York, N.Y.)
|January 3, 1992
まとめ
卵巣寄生性カウバードと新世界ブラックバード (Icterinae) は,卵巣寄生性が一度進化したことを示しています. ホスト特異性は原始的形態であり,ホスト一般性は,この鳥類ファミリーの派生条件である.
科学分野:
- 進化生物学の進化生物学について
- 鳥類学 鳥類学とは,鳥類学である.
- 分子系遺伝学 分子系遺伝学
背景:
- カウバードを含むイクテリーネ亜族は,異種間繁殖寄生性の多様な形態を現しています.
- 繁殖寄生虫の進化的起源を理解することは,鳥類ファミリーの進化にとって極めて重要です.
研究 の 目的:
- イクテリネ族 (Icterinae) 内の種間繁殖寄生体の進化的起源を調査する.
- 繁殖寄生病が複数回発生したか,または単一の祖先の出来事から発生したかどうかを判断する.
- 生殖寄生性の原始から派生形態への進化の軌道を特徴づける.
主な方法:
- サイトクロームb遺伝子の852塩基対領域の配列決定.
- カウバードと20の他のイクテリネ属の分類から得られた配列データを用いたクラディスティック法による系統分析.
主要な成果:
- 系統遺伝学的分析によると,種間繁殖寄生虫は,イクテリーナ族 (Icterinae) の内で一度だけ進化した.
- ホスト特異性は,このグループにおける子育て寄生性の祖先状態を表しています.
- ホストの一般性は,派生した進化的条件として識別される.
結論:
- Icterinaeの育児寄生体の進化史は,単一の起源イベントによって特徴付けられています.
- 宿主特異性から宿主一般性への移行は,イクテリーナ族 (Icterinae) の内における重要な進化的変化を意味する.
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