冷水性軟体動物は,一般の海洋軟体動物よりも古い
Steffen Kiel1, Crispin T S Little
1School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK. steffen.kiel@gmx.de
Science (New York, N.Y.)
|September 9, 2006
まとめ
化石モルスクの記録は,深海のシープファウナは,他の深海の生命と似て,古代の起源を持っていることを明らかにします. これらの発見は,シップ進化と世界的な無酸素現象を結びつける理論に挑戦しています.
科学分野:
- 海洋生物学 海洋生物学
- パレオントロジー・パレオントロジー
- 地質学 地質学 地質学
背景:
- 深海の噴出口と浸透ファウナの進化的起源と年齢は,その発見以来,議論の余地があります.
- これらのファウナを理解することは,深海の生態学と進化論の研究にとって極めて重要です.
研究 の 目的:
- シープモルスク動物群の地質年齢と進化史を調査する.
- 浸出ファウナの進化パターンを一般の海洋および深海の分類体と比較する.
- 深海の無酸素現象がシップファウナの進化に影響を与えたという仮説を検証するために.
主な方法:
- シープモルルスクの化石記録の分析.
- シープ属の地質的な範囲を一般の海洋軟体類や他の深海の分類体と比較する.
- 深海のアノキシック/ディオキシック現象が,浸出動物に与える影響の評価.
主要な成果:
- 生きているシップ属は,一般の海洋軟体動物よりも,地質学的にかなり長い範囲を示しています.
- シープ属の地質学的な範囲は,他の深海の分類体と比較できます.
- シープ・ファウナには,深海の無酸素/無酸素現象による重大な影響の証拠はない.
結論:
- 深海のシップファウナは,おそらく他の深海の生物と進化の原動力を共有しています.
- シープファウナの進化は,深海の無酸素現象と明らかに関連していない.
- 提案された無酸素性および/または過去無酸素性イベントの全般的な範囲は,再評価を必要とする場合があります.
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