コップの法則,過食性,そして北米の犬類の絶滅
Blaire Van Valkenburgh1, Xiaoming Wang, John Damuth
1Department of Ecology and Evolutionary Biology, University of California at Los Angeles, Los Angeles, CA 90095-1606, USA. bvanval@ucla.edu
Science (New York, N.Y.)
|October 2, 2004
まとめ
大きな肉食性哺乳類は,より大きなサイズの選択により絶滅の危機に直面しており,過肉食性と脆弱性の増大につながります. この進化の経路は,エネルギー的な制約によって駆動され,最終的に絶滅した北米の犬種でクラード障害を引き起こしました.
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
- 哺乳動物生態学 哺乳動物生態学
背景:
- 連続した大型肉食哺乳類のクラードは,過去5000万年にわたって多様化し,絶滅しました.
- これらの絶滅の原因は,しばしば十分に理解されていない.
- コップの法則は,多くの進化の系統において,より大きな体の大きさの普遍的な選択を記述しています.
研究 の 目的:
- 大きさの選択,食事の専門化,大型肉食哺乳類の絶滅リスクとの関連を調査する.
- エネルギー上の制約と過肉食が絶滅の脆弱性を高めるという仮説を検証する.
主な方法:
- 絶滅した北米犬種の2つの主要なクラードの分析.
- 体のサイズと食事の進化的傾向の検討.
- 食事の変化と種の生存期間と絶滅パターンとの相関関係.
主要な成果:
- これらの犬種群のより大きな大きさへの進化は,過剰肉食性への食事のシフトと関連していました.
- ハイパー肉食性の増加は,種寿命の減少と相関していた.
- より特殊な食事を持つ種は,より短い期間を示した.
結論:
- 肉食動物におけるより大きなサイズ (コップのルール) の選択は,過剰な肉食性および絶滅の脆弱性の増大につながる可能性があります.
- 個人の成功を促進する属性 (より大きなサイズ) は,クラードの漸進的な進化的失敗につながる可能性があります.
- エネルギー的な制約は,大型肉食動物の絶滅の動態において重要な役割を果たします.
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