Proterozoic Ocean Chemistry and Evolution: A Bioinorganic Bridge?
Recent data imply that for much of the Proterozoic Eon, Earth's oceans were moderately oxic at the surface and sulfidic at depth, and biologically important trace metals would have been scarce in most marine environments.
Estimating the timing of early eukaryotic diversification with multigene molecular clocks
- L. Parfrey, Daniel J G Lahr, A. Knoll, L. Katz
- Biology, GeographyProceedings of the National Academy of Sciences
- 2 August 2011
Taxon-rich multigene data combined with diverse fossils and a relaxed molecular clock framework are used to estimate the timing of the last common ancestor of extant eukaryotes and the divergence of major clades, suggesting that long stems preceded diversification in the major eUKaryotic lineages.
Eukaryotic organisms in Proterozoic oceans
- A. Knoll, E. Javaux, D. Hewitt, P. Cohen
- BiologyPhilosophical Transactions of the Royal Society B…
- 29 June 2006
Focus on character evolution permits inferences about the innovations in cell biology and development that underpin the taxonomic and morphological diversification of eukaryotic organisms.
The Evolution of Modern Eukaryotic Phytoplankton
The geological, geochemical, and biological processes that contributed to the rise of the dinoflagellates, coccolithophores, and diatoms all contain plastids derived from an ancestral red alga by secondary symbiosis are examined.
Stromatolites in Precambrian carbonates: evolutionary mileposts or environmental dipsticks?
Application of a process-based approach has shown that stromatolites were originally formed largely through in situ precipitation of laminae during Archean and older Proterozoic times, but that younger ProTerozoic strom atolites grew largely through the accretion of carbonate sediments, most likely through the physical process of microbial trapping and binding.
Large Perturbations of the Carbon Cycle During Recovery from the End-Permian Extinction
- J. Payne, D. Lehrmann, Jiayong Wei, M. Orchard, D. Schrag, A. Knoll
- Environmental Science, GeographyScience
- 23 July 2004
High-resolution carbon isotope measurements of multiple stratigraphic sections in south China demonstrate that the pronounced carbon isotopic excursion at the Permian-Triassic boundary was not an…
Neoproterozoic variations in the C-isotopic composition of seawater: stratigraphic and biogeochemical implications.
Biomarker evidence for green and purple sulphur bacteria in a stratified Palaeoproterozoic sea
- J. Brocks, G. Love, R. Summons, A. Knoll, G. Logan, S. Bowden
- Environmental Science, GeographyNature
- 6 October 2005
Hydrocarbon biomarkers from a 1.64-Gyr-old basin in northern Australia reveal a marine basin with anoxic, sulphidic, sulphate-poor and permanently stratified deep waters, hostile to eukaryotic algae, and support mounting evidence for a long-lasting Proterozoic world in which oxygen levels remained well below modern levels.
Isotopes, ice ages, and terminal Proterozoic earth history.
- A. J. Kaufman, A. Knoll, G. Narbonne
- Environmental Science, GeologyProceedings of the National Academy of Sciences…
- 24 June 1997
Detailed correlations of ancient glacial deposits, based on temporal records of carbon and strontium isotopes in seawater, indicate four (and perhaps five) discrete ice ages in the terminal…
The early evolution of eukaryotes: a geological perspective.
- A. Knoll
- 1 May 1992
Polecular phylogenies of eukaryotic organisms imply patterns of biological and environmental history that can be tested against the geological record, and Precambrian rocks show evidence of episodic increases in biological diversity and atmospheric oxygen concentrations.