Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Biotic turnover driven by eutrophication before the Sturtian low-latitude glaciation

Nature Geoscience volume 2, pages 415–418 (2009)Cite this article

Abstract

Reconstructions of the diversity of Precambrian microorganisms suggest a pronounced biotic turnover coinciding with the onset of Neoproterozoic low-latitude glaciation, in which diverse assemblages of organic-walled microfossils known as acritarchs were replaced by assemblages of simple, smooth-walled forms called leiosphaerids, and the remnants of bacterial blooms1,2,3,4. This turnover has been interpreted as the mass extinction of eukaryotic phytoplankton1,2,3,4 and the subsequent proliferation of bacteria5. However, the causes of this mass extinction and its exact temporal relationship to the glaciations remain unclear1,2,3,4. Here we present palaeontological data from the >742±6-Myr-old Chuar Group from Arizona, which indicate that the biotic turnover occurred before the first low-latitude (Sturtian) glaciation, constrained to be between 726 and 660 Myr in age6. In our record, the turnover is associated with the appearance of abundant and diverse protozoan fossils and a shift to rising total organic carbon, suggestive of increased primary productivity spurred by the influx of nutrients. This is followed by an increase in the ratio of highly reactive iron to total iron, which we interpret as persistent water column anoxia. We therefore conclude that the biotic turnover recorded in the Chuar Group was driven by widespread eutrophication of surface waters, rather than low-latitude glaciation.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Representative Chuar Group fossils.
Figure 2: Palaeontological and geochemical trends in Chuar Group strata.

Similar content being viewed by others

References

  1. Vidal, G. & Knoll, A. H. Radiations and extinctions of plankton in the late Proterozoic and early Cambrian. Nature 297, 57–60 (1982).

    Article  Google Scholar 

  2. Knoll, A. H. Proterozoic and Early Cambrian protists: Evidence for accelerating evolutionary tempo. Proc. Natl Acad. Sci. USA 91, 6743–6750 (1994).

    Article  Google Scholar 

  3. Vidal, G. & Moczydłowska-Vidal, M. Biodiversity, speciation, and extinction trends of Proterozoic and Cambrian phytoplankton. Paleobiology 23, 230–246 (1997).

    Article  Google Scholar 

  4. Moczydłowska, M. The Ediacaran microbiota and the survival of Snowball Earth conditions. Precambr. Res. 167, 1–15 (2008).

    Article  Google Scholar 

  5. Knoll, A. H., Blick, N. & Awramik, S. M. Stratigraphic and ecologic implications of late Precambrian microfossils from Utah. Am. J. Sci. 281, 247–263 (1981).

    Article  Google Scholar 

  6. Hoffman, P. F. & Li, Z.-X. A palaeogeographic context for Neoproterozoic glaciation. Palaeogeogr. Palaeoclimatol. Palaeoecol. 10.1016/j.palaeo.2009.03.013 (2009).

  7. Timmons, J. M., Karlstrom, K. E., Dehler, C. M., Geissman, J. W. & Heizler, M. T. Proterozoic multistage (∼1.1 and ∼0.8 Ga) extension in the Grand Canyon Supergroup and establishment of northwest and north–south tectonic grains in the southwestern United States. Geol. Soc. Am. Bull. 113, 163–180 (2001).

    Article  Google Scholar 

  8. Dehler, C. et al. High-resolution δ13C stratigraphy of the Chuar Group (about 770–742), Grand Canyon: Implications for mid-Neoproterozoic climate change. Geol. Soc. Am. Bull. 117, 32–34 (2005).

    Article  Google Scholar 

  9. Dehler, C. M. et al. Neoproterozoic Chuar Group (∼800–742 Ma), Grand Canyon: A record of cyclic marine deposition during global climatic and tectonic transitions. Sedim. Geol. 141/142, 465–499 (2001).

    Article  Google Scholar 

  10. Vidal, G. & Ford, T. D. Microbiotas from the Late Proterozoic Chuar Group (Northern Arizona) and Uinta Mountain Group (Utah) and their chronostratigraphic implications. Precambr. Res. 28, 349–389 (1985).

    Article  Google Scholar 

  11. Porter, S. M. & Knoll, A. H. Testate amoebae in the Neoproterozoic Era: Evidence from vase-shaped microfossils in the Chuar Group, Grand Canyon. Paleobiology 26, 360–385 (2000).

    Article  Google Scholar 

  12. Porter, S. M., Meisterfeld, R. & Knoll, A. H. Vase-shaped microfossils from the Neoproterozoic Chuar Group, Grand Canyon: A classification guided by modern testate amoebae. J. Paleontol. 77, 409–429 (2003).

    Article  Google Scholar 

  13. Summons, R. E. et al. Distinctive hydrocarbon biomarkers from fossiliferous sediment of the Late Proterozoic Walcott Member, Chuar Group, Grand Canyon, Arizona. Geochim. Cosmochim. Acta 52, 2625–2637 (1988).

    Article  Google Scholar 

  14. Ventura, G. T., Kenig, F., Grosjean, E. & Summons, R. E. 22nd International Meeting on Organic Geochemistry Vol. 2 Abstr. PB2–19 (Seville, 2005).

    Google Scholar 

  15. Weil, A. B., Geissman, J. W. & Van der Voo, R. Paleomagnetism of the Neoproterozoic Chuar Group, Grand Canyon Supergroup, Arizona: Implications for Laurentia’s Neoproterozoic APWP and Rodinia breakup. Precambr. Res. 129, 71–92 (2004).

    Article  Google Scholar 

  16. Dehler, C. M. The Chuar Group-Uinta Mountain Group-Pahrump Group connection revisited: A snapshot of the infra-Sturtian Earth system. Geol. Soc. Am. Abstr. Prog. 40, 36 (2008).

    Google Scholar 

  17. Timmons, M. J. et al. Tectonic inferences from the ca. 1255–1100 Ma Unkar Group and Nankoweap Formation, Grand Canyon: Intractratonic deformation and basin formation during protracted Grenville orogenesis. Geol. Soc. Am. Bull. 117, 1573–1595 (2005).

    Google Scholar 

  18. Karlstrom, K. E. et al. Chuar Group of the Grand Canyon: Record of breakup of Rodinia, associated change in the global carbon cycle, and ecosystem expansion by 740 Ma. Geology 28, 619–622 (2000).

    Article  Google Scholar 

  19. Williams, M. L. et al. Dating sedimentary sequences: In situ U/Th–Pb microprobe dating of early diagenetic monazite and Ar–Ar dating of marcasite nodules: Case study from Neoproterozoic black shales in the southwestern US. Geol. Soc. Am. Abstr. Prog. 35, 595 (2003).

    Google Scholar 

  20. Hill, A. C., Cotter, K. L. & Grey, K. Mid-Neoproterozoic biostratigraphy and isotope stratigraphy in Australia. Precambr. Res. 100, 281–298 (2000).

    Article  Google Scholar 

  21. Vidal, G. & Nystuen, J. P. Micropaleontology, depositional environment, and biostratigraphy of the Upper Proterozoic Hedmark Group, southern Norway. Am. J. Sci. A 290, 170–211 (1990).

    Google Scholar 

  22. Gong, Y.-M., Shi, G., Weldon, E., Du, Y.-S. & Xu, E. Pyrite framboids interpreted as microbial colonies within the Permian Zoophycus spreiten from southeastern Australia. Geol. Mag. 145, 95–103 (2008).

    Article  Google Scholar 

  23. Dehler, C. M., Porter, S. M., Grey, L. D. D., Sprinkel, D. A. & Brehm, A. in Proterozoic Geology of Western North American and Siberia (eds Link, P. K. & Lewis, R.) 151–166 (Special Publication 86, Society for Sedimentary Geology, 2007).

    Book  Google Scholar 

  24. Richardson, K. & Jørgensen, B. B. in Eutrophication in Coastal Marine Systems (eds Jørgensen, B. B. & Richardson, K.) 1–19 (American Geophysical Union, 1996).

    Book  Google Scholar 

  25. Diaz, R. J. & Rosenberg, R. Spreading dead zones and consequences for marine ecosystems. Science 321, 926–929 (2008).

    Article  Google Scholar 

  26. Dehler, C. M. Facies Analysis, Cyclostratigraphy, and Carbon-Isotope Stratigraphy of the Neoproterozoic Chuar Group, Eastern Grand Canyon, Arizona. PhD, Univ. New Mexico (2001).

  27. Swanson-Hysell, N. L., Maloof, A. C., Halverson, G. P. & Hurtgen, M. Covariation in the carbon isotopes of carbonate and organic carbon across the Neoproterozoic Bitter Springs Stage. Eos 89, Fall Meet. Suppl., Abstr. PP21B-1414 (2008).

  28. Hurtgen, M., Halverson, G. P., Swanson-Hysell, N. L. & Maloof, A. C. Early Neoproterozoic sulfur isotopes and the rise (and fall) of oxygen. Eos 89, Fall Meet. Suppl., Abstr. PP14A-05 (2008).

  29. Corsetti, F., Awramik, S. & Pierce, D. A complex microbiota from snowball Earth times: Microfossils from the Neoproterozoic Kingston Peak Formation, Death Valley, USA. Proc. Natl Acad. Sci. USA 100, 4399–4404 (2003).

    Article  Google Scholar 

  30. Corsetti, F. A., Olcott, A. N. & Bakermans, C. The biotic response to Neoproterozoic snowball Earth. Palaeogeogr. Palaeoclimatol. Palaeoecol. 232, 114–130 (2006).

    Article  Google Scholar 

Download references

Acknowledgements

A. Knoll is thanked for providing several of the samples. The authors benefited from discussions with S. Awramik, J. Bartley, K. Grey, G. Halverson, P. Hoffman, M. Hurtgen, D. Johnston, R. Kodner, A. Maloof, M. Moczydłowska, D. Valentine, G. Ventura and M. Vogel. D. Lamb helped with acid macerations. V. Atudorei, Z. Sharp, and D. Des Marais provided laboratory support for TOC analyses. F. Corsetti and G. Shields provided comments that greatly improved the manuscript. Sampling collection was made possible by support from the National Park Service and from the National Science Foundation through grant EAR-9706496. Financial support to R.M.N. and S.M.P. for this research was provided by the National Science Foundation through grant EAR-0420592. Financial support to Y.S. was provided by NSERC.

Author information

Authors and Affiliations

  1. Department of Earth Science, University of California at Santa Barbara, Santa Barbara, California 93106, USA

    Robin M. Nagy & Susannah M. Porter

  2. Department of Geology, Utah State University, 4505 Old Main Hill, Logan, Utah 84322-4505, USA

    Carol M. Dehler

  3. University of Quebec at Montreal, Quebec H3C 3P8, Canada

    Yanan Shen

Authors
  1. Robin M. Nagy
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Susannah M. Porter
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Carol M. Dehler
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Yanan Shen
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

S.M.P. wrote the paper, with contributions from C.M.D. and Y.S. All authors contributed data (R.M.N., organic-walled microfossils; S.M.P., vase-shaped microfossils; C.M.D., total organic carbon; Y.S., iron speciation), and provided intellectual input.

Corresponding author

Correspondence to Susannah M. Porter.

Supplementary information

Supplementary Fig. S1

Supplementary Information (PDF 576 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Nagy, R., Porter, S., Dehler, C. et al. Biotic turnover driven by eutrophication before the Sturtian low-latitude glaciation. Nature Geosci 2, 415–418 (2009). https://doi.org/10.1038/ngeo525

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ngeo525

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing