まとめ
パレオセアノグラフィの出来事は,深海のオストラコードに重大な影響を及ぼしました. クレータ紀と三次紀の境界線とサイクロスフィアの形成の出来事は,海洋生態系とオストラコードの分布を劇的に形を変えた.
科学分野:
- パレオセアノグラフィー
- マリン・バイオロジー マリン・バイオロジー
- パレオントロジー・パレオントロジー
背景:
- 深海には,極端な条件に適応したユニークな動物群が棲んでいます.
- オストラコードは,過去の海洋環境を再建するための貴重な微生物化石です.
- 古代海洋学的な出来事を理解することは,海洋生態系の研究において極めて重要です.
研究 の 目的:
- 深海のベンティック・オストラコード・ファウナに対する主要な古海洋学的出来事の影響を調査する.
- オストラコード分布の変化と特定の地質時間間隔と海洋学的な変化を相関させる.
主な方法:
- 全世界の深海のベンシック・オストラコードの動物変化の分析.
- 過去7000万年にわたる8つの認識されたまたは理論化された古海洋学イベントとの動物の変化の相関.
主要な成果:
- 2つのイベント,白紀-三次紀境界イベント (66 Ma) と心理圏形成 (40 Ma) は,最も重要な影響を示しました.
- 40万年前までは,オストラコードは,より深い水域への自由放射にもかかわらず,地方的でした.
- 熱分層化は,K-Tイベントの生存者である深水分類種の孤立と適応につながった.
結論:
- クレータ紀と三次紀の境界線と心理圏形成の出来事は,深海のオストラコードの多様性と生物地理を形作る上で重要な役割を果たしました.
- 海洋学的な変化,特に熱的層分化により,オストラコードの系統が生き残るために,新しい,広範囲に広がり,冷たい生態系が生まれました.
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