赤い女王が陸上の哺乳類を絶滅に追い込む方法
Tiago B Quental1, Charles R Marshall
1Universidade de São Paulo, Departamento de Ecologia, São Paulo, SP, Brazil. tbquental@usp.br
まとめ
種の絶滅はほとんど理解されていない. 絶滅した哺乳類の分析により,多様性の喪失は,単なる偶然ではなく,環境の変化に適応できないことから生じたことが明らかになった.
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:
- 背景絶滅の過程は,依然として十分に理解されていない.
- 陸上の哺乳類のクラードは絶滅や多様性の減少に直面しています.
- "ギャンブラーの破滅"と"レッドクイーン"の仮説は,種絶滅の説明を提供している.
研究 の 目的:
- 絶滅し,衰退しているケノゾイク陸上の哺乳類のクラードの進化の動態を分析する.
- これらのクラードにおける多様性喪失の要因を特定する.
- 絶滅における均衡と非均衡の過程の役割を調査する.
主な方法:
- 19のケノゾイク陸生哺乳類のクラードにおける進化動態の分析.
- 絶滅または衰退しているクラドの化石記録の調査.
- 環境圧力に関連した起源と絶滅率の評価.
主要な成果:
- 多様性の喪失は,環境の悪化に適応する進化の失敗 (レッドクイーン効果) の結果であり,単なる偶然 (ギャンブラーの破滅) の結果ではない.
- オリジネーション率の減少と絶滅率の上昇の両方が,多様性の減少に等しく貢献しました.
- 観察されたクラドの多様性は,均衡状態の多様性に一時的にしか一致せず,非均衡のダイナミクスを示した.
結論:
- 非均衡的過程は,陸上の哺乳類のクラードにおける多様性の損失を根本的に引き起こした.
- これらの非均衡的要因は,多様性に依存するプロセスを圧倒した.
- 環境変化に適応できないことが,哺乳類の絶滅の要因の1つである.
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