Pellet microfossils: Possible evidence for metazoan life in Early Proterozoic time
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Pellet microfossils: Possible evidence for metazoan life in Early Proterozoic time.
Microfossils resembling fecal pellets occur in acid-resistant residues and thin sections of Middle Cambrian to Early Proterozoic shale. The cylindrical microfossils average 50 x 110 mum and are the size and shape of fecal pellets produced by microscopic animals today. Pellets occur in dark gray and black rocks that were deposited in the facies that also preserves sulfide minerals and that repre...
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Evidence of Archean life: Stromatolites and microfossils
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In rocks of late Paleoproterozoic and Mesoproterozoic age (ca. 1700-1000 million years ago), probable eukaryotic microfossils are widespread and well preserved, but assemblage and global diversities are low and turnover is slow. Near the Mesoproterozoic-Neoproterozoic boundary (1000 million years ago), red, green, and chromophytic algae diversified; molecular phylogenies suggest that this was p...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1985
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.82.17.5809