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Low Mid-Proterozoic atmospheric oxygen levels and the delayed rise of animals

Planavsky, Noah J. and Reinhard, Christopher T. and Wang, Xiangli and Thomson, Danielle and McGoldrick, Peter and Rainbird, Robert H. and Johnson, Thomas and Fischer, Woodward W. and Lyons, Timothy W. (2014) Low Mid-Proterozoic atmospheric oxygen levels and the delayed rise of animals. Science, 346 (6209). pp. 635-638. ISSN 0036-8075.

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The oxygenation of Earth’s surface fundamentally altered global biogeochemical cycles and ultimately paved the way for the rise of metazoans at the end of the Proterozoic. However, current estimates for atmospheric oxygen (O₂) levels during the billion years leading up to this time vary widely. On the basis of chromium (Cr) isotope data from a suite of Proterozoic sediments from China, Australia, and North America, interpreted in the context of data from similar depositional environments from Phanerozoic time, we find evidence for inhibited oxidation of Cr at Earth’s surface in the mid-Proterozoic (1.8 to 0.8 billion years ago). These data suggest that atmospheric O₂ levels were at most 0.1% of present atmospheric levels. Direct evidence for such low O₂ concentrations in the Proterozoic helps explain the late emergence and diversification of metazoans.

Item Type:Article
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URLURL TypeDescription material
Reinhard, Christopher T.0000-0002-2632-1027
Fischer, Woodward W.0000-0002-8836-3054
Additional Information:Copyright © 2014, American Association for the Advancement of Science. Received for publication 7 July 2014. Accepted for publication 30 September 2014. N.J.P., C.T.R., X.W., T.J, and T.W.L. acknowledge funding from NASA Exobiology Program. N.J.P., C.T.R., and T.W.L. acknowledge funding from the NSF-ELT program. C.T.R. acknowledges an O.K. Earl fellowship from the California Institute of Technology. R.H.R. and D.T. acknowledge funding from a National Science and Engineering Research Council of Canada Discovery Grant and by Natural Resources Canada’s GEM Program. P.McG. acknowledges funding through the Australian Research Council's Centres of Excellence Program and thanks S. Gilbert for expert help with the LA-ICPMS work. We are indebted to A. Bekker, B. Maynard, A. Hofmann, K. Konhauser, J. Owens, C. Li, and G. Love for discussion and samples. Full data tables are in the supplementary materials.
Funding AgencyGrant Number
O.K. Earl Postdoctoral Fellowship, CaltechUNSPECIFIED
National Science and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Natural Resources CanadaUNSPECIFIED
Australian Research CouncilUNSPECIFIED
Issue or Number:6209
Record Number:CaltechAUTHORS:20141009-185334240
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Official Citation:Low Mid-Proterozoic atmospheric oxygen levels and the delayed rise of animals Noah J. Planavsky, Christopher T. Reinhard, Xiangli Wang, Danielle Thomson, Peter McGoldrick, Robert H. Rainbird, Thomas Johnson, Woodward W. Fischer, and Timothy W. Lyons Science 31 October 2014: 346 (6209), 635-638. [DOI:10.1126/science.1258410]
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:50325
Deposited By: George Porter
Deposited On:12 Nov 2014 00:26
Last Modified:09 Mar 2020 13:19

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