Morphological and ecological complexity in early eukaryotic ecosystems

@article{Javaux2001MorphologicalAE,
  title={Morphological and ecological complexity in early eukaryotic ecosystems},
  author={Emmanuelle J Javaux and Andrew H. Knoll and Malcolm R. Walter},
  journal={Nature},
  year={2001},
  volume={412},
  pages={66-69}
}
Molecular phylogeny and biogeochemistry indicate that eukaryotes differentiated early in Earth history. Sequence comparisons of small-subunit ribosomal RNA genes suggest a deep evolutionary divergence of Eukarya and Archaea; C27–C29 steranes (derived from sterols synthesized by eukaryotes) and strong depletion of 13C (a biogeochemical signature of methanogenic Archaea) in 2,700 Myr old kerogens independently place a minimum age on this split. Steranes, large spheroidal microfossils, and rare… 

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  • 2014
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TLDR
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TLDR
Recognition of eukaryotic fossils in Proterozoic rocks is key to the integration of geological and comparative biological perspectives on protistan evolution.

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  • Geography, Environmental Science
    Advances in experimental medicine and biology
  • 2007
TLDR
The record of biological innovations documented by the fossils shows that eukaryotes had evolved most cytological and molecular complexities very early in the Proterozoic but environmental conditions delayed their diversification within clades until oxygen level and predation pressure increased significantly.

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TLDR
Taxon-rich multigene data combined with diverse fossils and a relaxed molecular clock framework are used to estimate the timing of the last common ancestor of extant eukaryotes and the divergence of major clades, suggesting that long stems preceded diversification in the major eUKaryotic lineages.

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  • C. Blank
  • Environmental Science
    Journal of phycology
  • 2013
TLDR
It is proposed that early photosynthetic eukaryotes may have never experienced the widespread anoxia or euxinia suggested to have characterized marine environments in the Paleoproterozoic to early MesoproTerozoic, and that earliest acritarchs may have been produced by freshwater taxa.
...

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