セノゾイク時代の化石の軟体動物における種占有率の上昇と低下
Michael Foote1, James S Crampton, Alan G Beu
1Department of the Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637 USA. mfoote@uchicago.edu
Science (New York, N.Y.)
|November 17, 2007
まとめ
種の占有量はピークまで増加し,その後絶滅前に減少し,減少している種が最大の絶滅リスクに直面していることを示す. このパターンは,属と種の両方に当てはまります.
科学分野:
- パレオントロジー・パレオントロジー
- マクロエコロジー マクロエコロジー
- バイオジオグラフィー バイオジオグラフィー
背景:
- 長期の種占有パターンを理解することは,マクロエコロジーにとって極めて重要です.
- 地質学的時間尺度における種占有率の一般的なパターンは,ほとんど不明のままである.
研究 の 目的:
- ニュージーランドのケノゾイク期の海洋モルルカスの居住歴を記録し,分析する.
- 種占有率の一般的なパターンと,その種の絶滅リスクとの関係を特定する.
主な方法:
- 占有歴を再構築するために化石記録の分析.
- ケノゾーイク時代の属レベルと種レベルの両方の占有パターンの検討.
主要な成果:
- 占有率の明確なパターンが観察されました:中期ピークへの増加,その後絶滅への減少.
- 占有量が減少している種は,絶滅の危険性が高くなります.
- 種は,一般的に,一度確立されたピーク占有率を維持することはなく,インクンベンシーパターンとは対照的です.
結論:
- 種占有率は,長引く上昇と低下の軌道をたどっています.
- 絶滅の危険は,長期にわたる占有率の減少と関連しています.
- 長期の居住パターンは,マクロエコロジカルなプロセスと絶滅のダイナミクスについての洞察を提供します.
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