微生物の痕跡化石の形成,南極の寒い砂漠の生物学的および非生物学的気象の変化
1Department of Biological Science, Florida State University, Tallahassee 32306, USA.
Science (New York, N.Y.)
|May 8, 1987
まとめ
南極の砂漠に生息するクリプトエンドリホス型微生物は,繊細な要素のバランスを通して生き残る. 微生物の死は,化石の痕跡につながり,古代火星の生命の兆候を潜在的に反映する可能性があります.
科学分野:
- 天体生物学 アストロバイオロジー
- 微生物学 微生物学とは
- 地質学 地質学 地質学
背景:
- クリプトエンドロリシック微生物は,南極の寒い砂漠 (ロス砂漠) の多孔性砂岩岩に生息しています.
- これらの微生物の生存は,生物学的および地質学的条件の間の繊細な均衡に依存しています.
- 環境の変化は微生物の死を引き起こし,潜在的にその活動の化石化した痕跡を形成する可能性があります.
研究 の 目的:
- 極端な環境における暗号エンドロリシック微生物の生存メカニズムを調査する.
- 死んだ暗号エンドロリシックコミュニティから微生物の痕跡化石の形成の可能性を調査する.
- 火星で過去の生命の兆候を捜索する際の影響を評価する.
主な方法:
- 南極のロス砂漠でのフィールド観測とサンプル収集.
- 砂岩岩のサンプルを顕微鏡および地化学分析.
- 陸上の微生物の痕跡化石と潜在的な火星の地質学的記録の比較分析.
主要な成果:
- クリプトエンドロリシック生物の生存が環境の均衡に極めて依存していることを明らかにした.
- 死後の微生物の痕跡化石として鉄の浸出パターンの形成を記録した.
- 南極の微生物の痕跡化石と火星の潜在的なバイオシグネチャーの間の類似性を特定しました.
結論:
- クリプトエンドロリシックなコミュニティは,極端に寒い砂漠の環境変化に非常に敏感です.
- 微生物の活動により,地質学的な構造に認識可能な痕跡化石を残すことができます.
- この研究は,火星上の過去の生命の潜在的なバイオシグネチャを特定するためのモデルを提供します.
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