化石記録における絶滅の決定要因
Shanan E Peters1, Michael Foote
1Department of Geophysical Sciences, University of Chicago, IL 60637, USA. sepeters@midway.uchicago.edu
Nature
|March 29, 2002
まとめ
海洋動物の絶滅率に関する化石記録は,利用可能な岩の量によって歪められることがあります. 観測された多くの絶滅の揮発性は,真の絶滅の出来事ではなく,地層学的記録の人工物である可能性が高い.
科学分野:
- パレオバイオロジーの古生物学
- ストラティグラフィー ストラティグラフィー
- 地質学 地質学 地質学
背景:
- 大量絶滅と生物の選択性は,古生物学における重要な問題である.
- 堆積岩の利用可能性は,生物多様性と進化率の推定に偏りがあります.
- このサンプリングバイアスは,主要な絶滅のイベントで顕著です.
研究 の 目的:
- 推定絶滅率に対する堆積岩の利用可能性の影響を調査する.
- 観察された絶滅率の変動が真の信号なのか,サンプリングの人工物なのかを判断する.
- 異なる岩石の露出を考慮して,スムーズな絶滅率がどのように現れるかをモデル化するために.
主な方法:
- 海洋堆積岩の時間の経過による暴露データの収集.
- 真の絶滅率から化石記録の出現を予測するための統計モデリング.
- モデルの予測と観測された絶滅率のデータを比較する.
主要な成果:
- 露出岩の時間的な変動は,明らかな絶滅率の記録の多くの特徴を予測することができます.
- 観察された海洋動物の絶滅率の短期的な変動は,層図記録の変動と一致しています.
- この研究は,大量絶滅率の変動が人工物であるという仮説を裏付けている.
結論:
- ストラティグラフィック記録は,絶滅の出来事に対する私たちの認識に大きな影響を与えます.
- 観察された絶滅率の変動は,実際の生物学的絶滅の動態を正確に反映していない可能性があります.
- 将来の研究は,古生物学的研究における岩石曝露バイアスを考慮する必要があります.
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