クレタ紀の陸上革命とKPgの絶滅が哺乳類の多様化に及ぼす影響
Robert W Meredith1, Jan E Janečka, John Gatesy
1Department of Biology, University of California, Riverside, CA 92521, USA.
Science (New York, N.Y.)
|September 24, 2011
まとめ
この研究は,分子超行列を用いた哺乳類の系統樹を明らかにし,多様化の長フィューズモデルを支持し,主要な絶滅イベントを強調しています.
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
- ゲノミクスゲノミクスとは
背景:
- これまでの哺乳類の系統樹の再構築は,スーパーツリー方法と局所的な分子時計に依存していました.
- これらの方法には,哺乳類の進化史を理解するための解像度と精度の限界がありました.
研究 の 目的:
- 哺乳類の家族に強固な分子系統を作るために.
- 先進的な分析方法を使用して,分岐時間および多様化パターンを決定する.
- 大量絶滅の影響を含む哺乳類の多様化に関する仮説を検証する.
主な方法:
- 既存の哺乳類の家族のための包括的な分子超行列の構築.
- 概率に基づく方法を用いた系統遺伝学的分析.
- 複数の化石の校正によるリラックスした分子時計モデルの応用.
主要な成果:
- 高解像度で頑丈な哺乳類の系統遺伝子が生成され,以前のスーパーツリー方法を上回りました.
- リラックスクロック分析は,哺乳類の多様化のロングフィューズモデルを支持した.
- 証拠によると,白紀の陸上革命と白紀・旧紀 (KPg) の絶滅が哺乳類の多様化に大きく影響した.
結論:
- この研究は,哺乳類の進化を理解するためのより正確な系統遺伝的枠組みを提供します.
- 多様化パターンは,主要な地質学的および絶滅の出来事と密接に関連しています.
- 現代の哺乳類がエオセーン時代に遅れて出現したという仮説は支持されなかった.
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