ラオナステスと最近の哺乳類における"ラザラス効果"
Mary R Dawson1, Laurent Marivaux, Chuan-Kui Li
1Section of Vertebrate Paleontology, Carnegie Museum of Natural History, 4400 Forbes Avenue, Pittsburgh, PA 15213, USA. dawsonm@carnegiemnh.org
Science (New York, N.Y.)
|March 11, 2006
まとめ
ラオスの歯類Laonastes aenigmamusは,以前は自分の家族に属していると考えられていたが,実際には絶滅したDiatomyidaeファミリーの生き残ったメンバーである. この発見は,哺乳類における"ラザラス効果"を強調しており,1100万年後に再発見されました.
科学分野:
- パレオントロジー・パレオントロジー
- 動物学 動物学
- マンモロジーは,哺乳類学です.
背景:
- 2005年に発見された歯類Laonastes aenigmamusは,そのユニークな特徴と明らかな進化的孤立により,当初はLaonastidaeファミリーの唯一のメンバーとして分類されていました.
- この分類は,形態学的特徴と,生きたネズミの間の近親類が欠如しているとの認識に基づいていた.
研究 の 目的:
- ラオナステス・アニグマムスの系統遺伝的位置を再評価する.
- 形態学的および分子学的データを統合することによって,Laonastes aenigmamusの進化的関係を決定する.
主な方法:
- ラオナステス・アニグマムス (Laonastes aenigmamus) および様々な歯類ファミリーの形態学および分子データを併用した系統遺伝分析.
- Laonastes aenigmamusの主要な診断特性を評価するための比較解剖学的研究,化石歯類ファミリーとの比較.
主要な成果:
- Laonastes aenigmamusは,絶滅した歯類の家族であるDiatomyidaeの生き残ったメンバーとして再分類されています.
- Diatomyidaeの化石はアジア全土で発見されており,オリゴセンの初期からミオセンの終わりまで遡ります.
- この発見は,哺乳類の古生物学における重要な"ラザラス効果"を表しており,1100万年の不在の後,遺骨の分類体が再現しています.
結論:
- 現存するラオスの歯類 Laonastes aenigmamus は,新しい家族 Laonastidae ではなく,古代の Diatomyidae 家族に属しています.
- Diatomyidaeの再発見は,以前は化石からしか知られていなかったリリカルな系統のために,現存するファウナを調査することの重要性を強調しています.
- このケースは,古代哺乳類の系統が,広大な地質的な時間スケールにわたって生き残ったことを示し,ラザラス効果の顕著な例を提供します.
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