主要な海洋動物集団の多様性のバランスが変化している
1Paleobiology Database, University of California, 735 State Street, Santa Barbara, CA 93101, USA.
Science (New York, N.Y.)
|September 4, 2010
まとめ
主要な分類群は一貫した多様化率を持っていますが,絶滅や放射線により多様性の限界が変化することがあります. これは,現在の世界的な変化が,進化のルールと生物圏の組成を永久に変える可能性があることを示唆しています.
科学分野:
- パレオントロジー・パレオントロジー
- 進化生物学の進化生物学について
- エコロジー エコロジー エコロジー
背景:
- 化石記録は,主要な分類群が一貫した純多様化率と種の豊かさの限界を示すことを示唆しています.
- これらの特徴は,分類学的な集団の優位性における長期的な変化を予測すると考えられていた.
- 以前のモデルは,マクロ進化の傾向を予測するために静的な多様性の限界を想定していた.
研究 の 目的:
- 多様性の限界に基づいて,分類学的な集団の優位性の予測可能性を再評価する.
- 主要な進化的出来事への反応として,種の豊かさの限界のダイナミックな性質を調査する.
- 現在の世界的危機が生物圏の分類組成に及ぼす長期的な影響を理解する.
主な方法:
- 多様化率と種の豊かさを評価するために化石データの分析.
- 歴史的な適応放射線と大量絶滅の出来事の調査.
- 環境変化に対する分類群の反応の比較分析.
主要な成果:
- 多様性の限界は静的ではなく,増加したり減少したりすることができます.
- 多様性の限界の変化は,適応放射線や大量絶滅のような特異的な出来事によって引き起こされます.
- ペルミア期末のような大規模な絶滅は,以前支配的であった分類種 (例えば,ブラキオポッド,クリノイド) の多様性を永久に減少させる可能性があります.
結論:
- 長期的な支配的なパターンは,一貫した多様化率と固定された多様性制限によってのみ予測することはできません.
- 大規模な絶滅は,進化の軌跡と生物圏の分類構造を根本的に変えてしまう.
- 現在の世界的な危機は,進化のルールを再構築し,地球上の生命の組成を永久に変える可能性があります.
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