ソビエト連邦のコノフィトンにおける微生物化石と,その影響がプレカンブリア生物ストラティグラフィに及ぼす影響
まとめ
南カザフスタンのヴェンディアン (後のプレカンブリア) コノフィトン化石は,多様なシアノフィット藻類とユーカリオット藻類を明らかにしています. これらの微生物は,彼らが形成したストロマトライトとは異なり,プレカンブリア-カンブリア絶滅のイベントに生き残った.
科学分野:
- パレオントロジー・パレオントロジー
- 微生物学 微生物学とは
- 地質学 地質学 地質学
背景:
- ヴェンディアン (後のプレカンブリア) 時代は,初期の生命の進化を理解するために極めて重要です.
- コノフィトンを含むストロマトライトは,古代の微生物生態系の重要な指標である.
- プレカンブリアとカンブリアの境界線は,地球の歴史における重要な絶滅の出来事を表しています.
研究 の 目的:
- コノフィトンガウビツァ・ストロマトライトの微生物組成を調べるために.
- これらの古代の構造に存在する藻類の種類を特定するために.
- プレカンブリア時代を超えてストロマトライトを形成する微生物の生存率を決定する.
主な方法:
- 南カザフスタンのシリカ化されたコノフィトンガウビツァ標本の分析.
- 保存された微生物を特定し,分類するための顕微鏡検査.
- 微生物群の生存とストロマトライトの絶滅パターンの比較.
主要な成果:
- コノフィトン (Conophyton) の内部で,保存状態が良好なシアノフィティック藻類とユーカリオティック藻類の多様な集合体の発見.
- これは,ソビエト連邦から初めて報告されたストロマトリチス菌群を表しています.
- 特定された微生物は,プレカンブリア紀の終わりに絶滅しなかった.
結論:
- コノフィトン・ガウビツァ・ストロマトライトは,複雑な微生物コミュニティを宿していた.
- これらのストロマトライトの構築者は,これまで考えられていたよりも大きな回復力を示しています.
- この発見は,プレカンブリア・カンブリア微生物絶滅の発生に関する既存のモデルに異議を唱えている.
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