絶滅した有袋狼のDNAの原始化
R H Thomas1, W Schaffner, A C Wilson
1Department of Biochemistry, University of California, Berkeley 94720.
Nature
|August 10, 1989
まとめ
絶滅した marsupial wolf (Thylacinus cynocephalus) は,ミトコンドリアDNA分析に基づいて,南米のものよりもオーストラリアの marsupials により密接に関連しています. この発見は,その進化の歴史を明らかにし,他の種との収束進化を強調しています.
科学分野:
- 進化生物学の進化生物学について
- パレオントロジー・パレオントロジー
- 遺伝学 遺伝学とは
背景:
- 絶滅した marsupial wolf (Thylacinus cynocephalus) の系統遺伝的位置は議論されており,南米およびオーストラリアの肉食性 marsupials との関連性を示唆する形態学的研究が行われています.
- アルブミン抗原性に基づく以前の研究も洞察を提供したが,タイラシンの進化的関係を明確に解決することはできなかった.
研究 の 目的:
- 分子データを用いて,有袋狼の正確な系統遺伝的属性を決定する.
- Thylacinus cynocephalusと現存する有袋動物群の間の進化的関係を調査する.
主な方法:
- ミトコンドリア (mt) DNAの219の塩基対の直接シーケンシング. 袋鼠狼の博物館標本から.
- 得られたDNA配列を,現在存在する有袋類の6つの属のDNA配列と比較.
主要な成果:
- ミトコンドリアDNA配列のデータは,マサピアルオオカミがオーストラリアのマサピアル肉食動物とより密接に関連していることを示しています.
- これらの遺伝的発見は,アルバミンに関する以前の免疫学的研究と一致しています.
- この結果は,南米の肉食性 marsupial との形態学的類似性は,収束進化の例であることを示唆しています.
結論:
- marsupial wolf (Thylacinus cynocephalus) は,オーストラリアの marsupial に属している.
- 南米のボリヤエニドに似ているのは,近親関係ではなく,収束的な進化によるものだ.
- この研究は,象徴的な絶滅した marsupial.の進化史を明らかにします.
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