Rapid emergence of life shown by discovery of 3,700-million-year-old microbial structures

@article{Nutman2016RapidEO,
  title={Rapid emergence of life shown by discovery of 3,700-million-year-old microbial structures},
  author={Allen P. Nutman and Vickie C. Bennett and Clark R.L. Friend and Martin J. Van Kranendonk and Allan r. Chivas},
  journal={Nature},
  year={2016},
  volume={537},
  pages={535-538}
}
Biological activity is a major factor in Earth’s chemical cycles, including facilitating CO2 sequestration and providing climate feedbacks. Thus a key question in Earth’s evolution is when did life arise and impact hydrosphere–atmosphere–lithosphere chemical cycles? Until now, evidence for the oldest life on Earth focused on debated stable isotopic signatures of 3,800–3,700 million year (Myr)-old metamorphosed sedimentary rocks and minerals from the Isua supracrustal belt (ISB), southwest… Expand
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References

SHOWING 1-10 OF 36 REFERENCES
Evidence for life on Earth before 3,800 million years ago
IT is unknown when life first appeared on Earth. The earliest known microfossils (˜3,500 Myr before present) are structurally complex, and if it is assumed that the associated organisms required aExpand
Reassessing the evidence for the earliest traces of life
TLDR
It is shown that graphite occurs abundantly in secondary carbonate veins in the ISB that are formed at depth in the crust by injection of hot fluids reacting with older crustal rocks (metasomatism); these metasomatic rocks, which clearly lack biological relevance, were earlier thought to be of sedimentary origin. Expand
Carbon isotope geochemistry of the 3.7 × 109-yr-old Isua sediments, West Greenland: implications for the Archaean carbon and oxygen cycles
One hundred and twenty-four carbonate samples from the meta-sedimentary sequence of the 3.7 × 109 yr old Isua supracrustal belt (W-Greenland) have yielded a δ13Ccarb average of −2.5 ± 1.7%. vs PDBExpand
Stromatolite reef from the Early Archaean era of Australia
TLDR
A multi-kilometre-scale palaeontological and palaeoenvironmental study of the Strelley Pool Chert, in which the first morphotype-specific analysis of the structures within their palaioenvironment and refute contemporary abiogenic hypotheses for their formation are undertaken. Expand
Microbial mediation as a possible mechanism for natural dolomite formation at low temperatures
DOLOMITE (CaMg(CO3)2) is a common carbonate mineral which is found in much greater abundance in ancient rocks than in modern carbonate environments. Why this is so remains a mystery. Over the past 30Expand
Geological and trace element evidence for a marine sedimentary environment of deposition and biogenicity of 3.45 Ga stromatolitic carbonates in the Pilbara Craton, and support for a reducing Archaean ocean
Bedded carbonate rocks from the 3.45 Ga Warrawoona Group, Pilbara Craton, contain structures that have been regarded either as the oldest known stromatolites or as abiotic hydrothermal deposits. WeExpand
Seawater-like trace element signatures (REE + Y) of Eoarchaean chemical sedimentary rocks from southern West Greenland, and their corruption during high-grade metamorphism
Modern chemical sediments display a distinctive rare earth element + yttrium (REE + Y) pattern involving depleted LREE, positive La/La*SN, Eu/Eu*SN, and YSN anomalies (SN = shale normalised) that isExpand
≥3700 Ma pre-metamorphic dolomite formed by microbial mediation in the Isua supracrustal belt (W.Greenland): Simple evidence for early life?
Chemical (meta)sedimentary rocks in the amphibolite facies ≥3700 Ma Isua supracrustal belt (W. Greenland) are mostly strongly deformed, so there is only a small chance of the survival of featuresExpand
An abiotic model for stromatolite morphogenesis
TLDR
This work deduces, from both the microscopic textures and the fractal dimension, a purely abiotic dynamical model of stromatolite surface growth that combines chemical precipitation on the growing interface, fallout and diffusive rearrangement of suspended sediment, and uncorrelated random noise. Expand
Stromatolites 3,400–3,500 Myr old from the North Pole area, Western Australia
Stromatolites are the least controversial evidence of early life; they are organosedimentary structures resulting from the growth and metabolic activity of microorganisms1. Before this report,Expand
...
1
2
3
4
...