3,235百万年前の火山原の大量硫化物堆積地の繊維状の微生物化石
1Department of Geology and Geophysics, University of Western Australia, Nedlands, Australia. brasmuss@geol.uwa.edu.au
Nature
|June 23, 2000
まとめ
研究者らは,3,235百万年前の深海の水熱貯蔵庫で,古代の微生物化石を発見した. この発見は,海底温泉におけるプレカンブリア時代以前の微生物生物の化石証拠を初めて提供している.
科学分野:
- * プレカンブリア時代以前の古生物学
- * 天体生物学 (アストロバイオロジー)
- * ジオバイオロジー
背景:
- *アーケア紀の微生物化石の化石記録は稀で,主に浅瀬の水域のストロマトリート環境からのものです.
- * 深海の熱水システムからの微生物化石は,プレカンブリア時代の岩石では報告されていません.
- * 熱性微生物は,潜在的に古代の系統であり,現代の熱水噴出孔では一般的です.
研究 の 目的:
- * プレカンブリア時代以前の深海水熱貯蔵庫で微生物化石が発見されたことを報告する.
- * 初期の微生物生命の性質と環境を調査する.
- *海底熱水生物の既知の化石記録を拡張する.
主な方法:
- * 3,235 百万年前の火山性大規模な硫化物堆積物の地質学的分析.
- *ピリート繊維を微生物化石の残骸として識別・特徴づけ.
- * 地質学的な文脈における微生物化石の発生の解釈.
主要な成果:
- * 化石化した微生物である可能性が高いピリート繊維の発見,3.235億年前の埋蔵物.
- *これらの微生物は,熱性化学性プロカリオートとして解釈されます.
- *化石は海底の水熱環境に住んでいた.
結論:
- * これは,プレカンブリア期以前の海底温泉系における微生物生命の化石証拠を初めて示しています.
- *海底熱水生物の既知の範囲を2,700億年以上延長する.
- * 初期の生命は,熱愛的な海底水熱環境で発生した可能性があるという仮説を支持する.
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