ファネロゾイク期の海洋無脊椎動物におけるエスカレートする生態学的傾向の統計的独立性
Joshua S Madin1, John Alroy, Martin Aberhan
1National Center for Ecological Analysis and Synthesis, University of California, Santa Barbara, CA 93101, USA. madin@nceas.ucsb.edu
Science (New York, N.Y.)
|May 13, 2006
まとめ
生態学的相互作用は,何百万年にもわたる海洋無脊椎動物のマクロ進化の傾向を駆動するものではありません. 化石データは,生態系集団とマクロ進化のエスカレーションとの間に有意な関連性がないことを示している.
科学分野:
- パレオントロジー・パレオントロジー
- マクロエボリューション
- 海洋生態学 海洋生態学とは
背景:
- 捕食とバイオターバーションのような生態学的相互作用は,マクロ進化の動向の推論された原動力である.
- 以前の研究は,これらの相互作用が進化の軌道を根本的に形作ることを示唆していた.
研究 の 目的:
- 生態学的相互作用,特に捕食とバイオターバーションが,ベンティック海洋無脊椎動物におけるマクロ進化の傾向を駆動しているかどうかを調査する.
- ファネロゾーイク時代の全世界の化石発生データを分析する.
主な方法:
- ベンシック海洋無脊椎動物のファネロゾイク期の化石発生に関するグローバルなデータセットをまとめました.
- 生態系のグループ (肉食動物,動物,移動生物など) の相対的な頻度に関する傾向を分析した.
- 保存バイアスを考慮して,生態学的傾向とマクロ進化のエスカレーションの間の統計的関連を評価した.
主要な成果:
- 特定の生態系群の相対的な周波数におけるエスカレート傾向が観察された.
- これらの生態学的傾向とマクロ進化のエスカレーションとの間に統計的に有意な関連性は見つかりませんでした.
- 分類学的な富と発生データとの交叉相関を特定し,その使用をプロキシとして検証しました.
結論:
- 生態学的相互作用は,地球規模で,百万年の時間スケールでマクロ進化のトレンドを駆動しているようには見えません.
- 保存効果は,生態学的エスカレーションではなく,観察された関連を説明する可能性があります.
- 分類学的な豊かさは,古生物学的研究における発生データの有効なプロキシであり続けています.
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