オールドビキア期からのグロマリアン菌類
D Redecker1, R Kodner, L E Graham
1Department of Plant and Microbial Biology, 111 Koshland Hall, University of California, Berkeley, CA 94720, USA. redecker@nature.berkeley.edu
まとめ
オールドビキア期からの古代の真菌化石は,グロマレス類の真菌が初期の陸上の植物と共存していたことを示唆しています. これらの発見は,植物植民と初期の陸上の生態系における真菌の重要な役割を支持しています.
科学分野:
- パレオミコロジー (古生物学)
- 植物と真菌の相互作用
- 初期の地上の生態系
背景:
- オールドビキア期 (4億8500万~4億4300万年前) は,植物の土地の初期植民を目撃した.
- 陸上の真菌の進化的起源は議論されているが,分子データは6億年前に起源を示唆している.
研究 の 目的:
- 初期の地上の真菌の存在と形態を調査する.
- 植物の地球化を促進するこれらの真菌の潜在的な役割を評価する.
主な方法:
- 化石化した真菌ヒフェと胞子の顕微鏡検査.
- 化石の真菌と現代の真菌群の形態学的比較,特に状真菌.
主要な成果:
- ウィスコンシン州オルドヴィチカ期の化石 (約. 4億6000万年前の) は,現代の状菌類 (Glomales,Zygomycetes) に似た特徴を示している.
- これらのグロマレスのような真菌は,陸上植生がブリオフィートレベルの植物に限られていた頃には存在していた.
- この発見は,地球上の主要な真菌群の起源を約6億年前に位置づける分子遺伝学的な推定と一致しています.
結論:
- 化石の証拠は,植物の地球化初期の段階で,グローマレス類の真菌の存在を示しています.
- これらの古代の真菌は,植物の陸上植民を可能にするために重要な役割を果たしたのかもしれない.
- 化石記録は,地上の真菌の多様化に関する分子時計の推定を支持している.
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