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Estimated evolutionary emergence of phytoplankton

Range	2.7 to 2.4 Billion years ago
Organism	Biosphere
Reference	Quigg A, Irwin AJ, Finkel ZV. Evolutionary inheritance of elemental stoichiometry in phytoplankton. Proc Biol Sci. 2011 Feb 22 278(1705):526-34. p.526 left column top paragraphPubMed ID20826483
Primary Source	Brocks, J. J., Logan, G. A., Buick, R. & Summons, R. E. 1999 Archean molecular fossils and the early rise of eukaryotes. Science 285, 1033–1036 AND Summons, R. E., Jahnke, L. L., Hope, J. M. & Logan, G. A. 1999 2-Methylhopanoids as biomarkers for cyanobacterial oxygenic photosynthesis. Nature 400, 554–557. (doi:10.1038/23005) AND Knoll, A. H., Javaux, E. J., Hewitt, D. & Cohen, P. 2006 Eukaryotic organisms in Proterozoic oceans. Phil. Trans R. Soc. B 361, 1023–1038. (doi:10.1098/rstb. 2006.1843)PubMed ID10446042, 10448856, 16754612
Comments	Based on inferred atmospheric and oceanic oxygen concentrations, biomolecular and isotopic evidence, phytoplankton may have been present 2.7–2.4 Ga ago. For date of great oxidation event 2.45 Ga ago see Gantt 2011 PMID 21190136 p.2 left column 2nd paragraph
Entered by	Uri M
ID	106949