A timeline showing OMZ (oxygen minimum zone) chemistry, the relative contributions from different primary producers, and the evolution of eukaryotic heterotrophs

Range Figure - link Mya
Organism Biosphere
Reference Johnston DT, Wolfe-Simon F, Pearson A, Knoll AH. Anoxygenic photosynthesis modulated Proterozoic oxygen and sustained Earth's middle age. Proc Natl Acad Sci U S A. 2009 Oct 6 106(40):16925-9. doi: 10.1073/pnas.0909248106 p.16928 fig. 3PubMed ID19805080
Primary Source See pointers to refs in caption below graph, list of refs above graph
Comments Note-For graph scroll down to 2nd page. "A timeline showing OMZ chemistry (1– 4, 7–10, 13, 14, 17), the relative contributions from different primary producers (17, 55, 69), and the evolution of eukaryotic heterotrophs (55–59, 70, 71). Band thicknesses approximate the importance of each feature through time. Dashed lines represent postulated or uncertain histories. The specific evolutionary sequence of oxygenic and anoxygenic photoautotrophs (including both cyanobacteria and purple/green S bacteria), marked here by **, rests in the Archean rock record (2,500 Ma). As both processes had evolved by 1,800 Ma (23) (when [researchers'] story begins), [they] make, nor require, any distinct sequence. The two thicker vertical lines represent the major Neoproterozoic glaciations (72), and the thinner line to the right marks the Ediacaran Gaskiers glaciation. The precise timing of Neoproterozoic climatic and biogeochemical events is the subject of ongoing research. [Researchers] highlight the mixed contributions to primary productivity through the Proterozoic, a transition in OMZ chemistry at 800–700 Ma, and the coincident change in cyanobacteria, algal, protist, and animal abundances, based on body and molecular fossils."
Entered by Uri M
ID 110483