2014 Fiscal Year Final Research Report
Early evolution of eukaryotic microorganisms in Archean oxygen oasis produced by cyanobacteria
Project/Area Number |
24654162
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Research Category |
Grant-in-Aid for Challenging Exploratory Research
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Allocation Type | Multi-year Fund |
Research Field |
Geology
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Research Institution | Nagoya University |
Principal Investigator |
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Co-Investigator(Kenkyū-buntansha) |
MIMURA Koichi 名古屋大学, 大学院環境学研究科, 准教授 (80262848)
ASAHARA Yoshihiro 名古屋大学, 大学院環境学研究科, 助教 (10281065)
TAKEUCHI Makoto 名古屋大学, 大学院環境学研究科, 教授 (80273217)
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Project Period (FY) |
2012-04-01 – 2015-03-31
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Keywords | 真核生物 / 太古代 / 酸素オアシス / シアノバクテリア / ピルバラクラトン |
Outline of Final Research Achievements |
We performed detailed studies on Archean microfossils collected from multiple localities in the 3.0 Ga Farrel Quartzite (FQ) in the Pilbara Craton, Western Australia, with referring to the 3.4 Ga Strelley Pool microfossils (stored in Nagoya University). The PI has discovered some very important specimens including large lenses with single to several objects inside, which provide constraint on biological affinity (eukaryotic) of lenticular microfossils. Also high resolution SEM analyses revealed that sheet-like appendage (flange) is composed of fine meshwork, which suggests the possibility that the structure is constructed and maintained by cytoskeleton. Also carbon isotopic values of individual microfossils were determined, revealing that their data are distinct from the isotopic values of the matrix carbonaceous particles. Concentration of phosphorous and nitrogen in the structures was also confirmed. With these results, the biogenicity of FQ microfossils is firmly established.
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Free Research Field |
地球生物学
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