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Fossil steroids record the appearance of Demospongiae during the Cryogenian period

Nature volume 457, pages 718721 (05 February 2009) | Download Citation


The Neoproterozoic era (1,000–542 Myr ago) was an era of climatic extremes and biological evolutionary developments culminating in the emergence of animals (Metazoa) and new ecosystems1. Here we show that abundant sedimentary 24-isopropylcholestanes, the hydrocarbon remains of C30 sterols produced by marine demosponges, record the presence of Metazoa in the geological record before the end of the Marinoan glaciation (635 Myr ago). These sterane biomarkers are abundant in all formations of the Huqf Supergroup, South Oman Salt Basin, and, based on a new high-precision geochronology2, constitute a continuous 100-Myr-long chemical fossil record of demosponges through the terminal Neoproterozoic and into the Early Cambrian epoch. The demosponge steranes occur in strata that underlie the Marinoan cap carbonate (>635 Myr ago). They currently represent the oldest evidence for animals in the fossil record, and are evidence for animals pre-dating the termination of the Marinoan glaciation. This suggests that shallow shelf waters in some late Cryogenian ocean basins (>635 Myr ago) contained dissolved oxygen in concentrations sufficient to support basal metazoan life at least 100 Myr before the rapid diversification of bilaterians during the Cambrian explosion. Biomarker analysis has yet to reveal any convincing evidence for ancient sponges pre-dating the first globally extensive Neoproterozoic glacial episode (the Sturtian, 713 Myr ago in Oman2).

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  1. 1.

    , , & The Ediacaran emergence of bilaterians: Congruence between the genetic and the geological fossil records. Phil. Trans. R. Soc. B 363, 1435–1443 (2008)

  2. 2.

    et al. Geochronologic constraints on the chronostratigraphic framework of the Neoproterozoic Huqf Supergroup, Sultanate of Oman. Am. J. Sci. 307, 1097–1145 (2007)

  3. 3.

    , , & Oxidation of the Ediacaran ocean. Nature 444, 744–747 (2006)

  4. 4.

    The Sedimentology and Chemostratigraphy of the Nafun Group, Huqf Supergroup, Oman. Thesis, Univ. Oxford (2000)

  5. 5.

    , , , & Origin of crude oils in Oman. J. Petrol. Geol. 11, 61–80 (1988)

  6. 6.

    , , & Origin of free and bound mid-chain methyl alkanes in oils, bitumens and kerogens of the marine, Infracambrian Huqf Formation (Oman). Org. Geochem. 30, 1411–1428 (1999)

  7. 7.

    , , & Release of covalently-bound biomarkers in high yields from kerogen via catalytic hydropyrolysis. Org. Geochem. 23, 981–986 (1995)

  8. 8.

    , , & Comparison of covalently-bound aliphatic biomarkers released via hydropyrolysis with their solvent-extractable counterparts for a suite of Kimmeridge clays. Org. Geochem. 29, 1487–1505 (1998)

  9. 9.

    et al. Biomarker evidence for green and purple sulphur bacteria in a stratified Palaeoproterozoic sea. Nature 437, 866–870 (2005)

  10. 10.

    , , & 2-Methylhopanoids as biomarkers for cyanobacterial oxygenic photosynthesis. Nature 400, 554–556 (1999)

  11. 11.

    Sterols in microorganisms. Appl. Microbiol. Biotechnol. 60, 495–506 (2003)

  12. 12.

    et al. Sedimentary 24-n-propylcholestanes, molecular fossils diagnostic of marine algae. Science 247, 309–312 (1990)

  13. 13.

    , & Sterol composition and classification of the Demospongiae. Biochem. Syst. Ecol. 8, 423–435 (1980)

  14. 14.

    , & Biosynthetic studies of marine lipids 35. The demonstration of de novo sterol biosynthesis in sponges using radiolabelled isoprenoid precursors. Comp. Biochem. Physiol. B 99, 763–773 (1991)

  15. 15.

    et al. Paleoenvironmental implications of novel C30 steranes in Precambrian to Cenozoic age petroleum and bitumen. Geochim. Cosmochim. Acta 58, 529–532 (1994)

  16. 16.

    , , , & Sterols in a unicellular relative of the metazoans. Proc. Natl Acad. Sci. USA 105, 9897–9902 (2008)

  17. 17.

    & Life after snowball: The oldest complex Ediacaran fossils. Geology 31, 27–30 (2003)

  18. 18.

    , & Trace fossils and substrates of the terminal Proterozoic-Cambrian transition: Implications for the record of early bilaterians and sediment mixing. Proc. Natl Acad. Sci. USA 99, 12572–12576 (2002)

  19. 19.

    et al. Doushantuo embryos preserved inside diapause egg cysts. Nature 446, 661–663 (2007)

  20. 20.

    & Long expected sponges from the Neoproterozoic Ediacaran fauna of South Australia. J. Paleontol. 70, 185–195 (1996)

  21. 21.

    , & Ediacarian sponge spicule clusters from southwestern Mongolia and the origins of the Cambrian fauna. Geology 25, 303–306 (1997)

  22. 22.

    , & Precambrian sponges with cellular structures. Science 279, 879–882 (1998)

  23. 23.

    , & Three-dimensional preservation of algae and animal embryos in a Neoproterozoic phosphorite. Nature 391, 553–558 (1998)

  24. 24.

    , & in The Rise and Fall of the Ediacaran Biota (eds Vickers-Rich, P. & Komarower, P.) 355–368 (Geological Society Special Publications, 2007)

  25. 25.

    et al. Estimating metazoan divergence times with a molecular clock. Proc. Natl Acad. Sci. USA 101, 6536–6541 (2004)

  26. 26.

    & Origin of the Eumetazoa: Testing ecological predictions of molecular clocks against the Proterozoic fossil record. Proc. Natl Acad. Sci. USA 102, 9547–9552 (2005)

  27. 27.

    et al. A chemical view of the most ancient metazoa – biomarker chemotaxonomy of hexactinellid sponges. Naturwissenschaften 89, 60–66 (2002)

  28. 28.

    , , & Sterol composition and classification of the Porifera. Biochem. Syst. Ecol. 19, 17–24 (1991)

  29. 29.

    , & Dynamics of the Neoproterozoic carbon cycle. Proc. Natl Acad. Sci. USA 100, 8124–8129 (2003)

  30. 30.

    et al. Pulsed oxidation and biological evolution in the Ediacaran ocean. Proc. Natl Acad. Sci. USA 105, 3197–3202 (2008)

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Funding support for this work came from Petroleum Development Oman (PDO), the NASA Exobiology Program, the NSF EAR Program, the Agouron Institute and the NASA Astrobiology Institute. We thank PDO for access to sample materials and Z. Rawahi and P. Taylor, in particular, for their input. C. Colonero, R. Kayser and A. Lewis provided laboratory assistance, including the maintenance of mass spectrometers at MIT.

Author Contributions G.D.L. interpreted the data and wrote the manuscript with input from R.E.S, D.A.F, A.S.B and E.G. G.D.L., E.G., C.S. and A.E.K. acquired the Huqf biomarker data working in the research group of R.E.S. A.S.B. and M.B. screened extant demosponges for their sterol contents. C.E.S. and W.M. made facilities available for HyPy experiments on kerogens and trained C.S. to use the equipment. J.P.G. provided a robust stratigraphic framework for the Huqf Supergroup in the SOSB and with D.A.F. identified key sedimentary rock samples to use in this investigation. S.A.B and D.J.C. measured important U–Pb ages for ash beds and detritral zircons through the stratigraphy to constrain the age range and distribution of our demosponge biomarkers.

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Author notes

    • Daniel J. Condon

    Present address: NERC Isotope Geosciences Laboratory, Keyworth, Nottingham NG12 5GG, UK.


  1. Department of Earth Sciences, University of California, Riverside, California 92521, USA

    • Gordon D. Love
  2. Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 01239, USA

    • Gordon D. Love
    • , Alexander S. Bradley
    • , Amy E. Kelly
    • , Maya Bhatia
    • , Samuel A. Bowring
    • , Daniel J. Condon
    •  & Roger E. Summons
  3. Petroleum and Marine Division, Geoscience Australia, Canberra, Australian Capital Territory 2601, Australia

    • Emmanuelle Grosjean
  4. School of Civil Engineering and Geosciences, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, UK

    • Charlotte Stalvies
  5. Department of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA

    • David A. Fike
    •  & John P. Grotzinger
  6. School of Chemical, Environmental and Mining Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK

    • William Meredith
    •  & Colin E. Snape


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Corresponding author

Correspondence to Gordon D. Love.

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    Supplementary Information

    This file contains Supplementary Data, Supplementary Figure 1 with Legend, Supplementary Tables 1-4, Supplementary Results, a Supplementary Discussion and Supplementary References

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