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Biologically Induced Initiation of Neoproterozoic Snowball-Earth Events
(Proceedings of the National Academy of Sciences, 2011)
The glaciations of the Neoproterozoic Era (1,000 to 542 MyBP) were preceded by dramatically light C isotopic excursions preserved in preglacial deposits. Standard explanations of these excursions involve remineralization ...
Opportunity Mars Rover mission: Overview and selected results from Purgatory ripple to traverses to Endeavour crater
(Wiley-Blackwell, 2011)
[1] Opportunity has been traversing the Meridiani plains since 25 January 2004 (sol 1), acquiring numerous observations of the atmosphere, soils, and rocks. This paper provides an overview of key discoveries between sols ...
Skeletons and Ocean Chemistry: The Long View
(Oxford University Press, 2011)
Ancient Aqueous Environments at Endeavour Crater, Mars
(American Association for the Advancement of Science (AAAS), 2014)
Opportunity has investigated in detail rocks on the rim of the Noachian age Endeavour crater, where orbital spectral reflectance signatures indicate the presence of Fe+3-rich smectites. The signatures are associated with ...
A Basin Redox Transect at the Dawn of Animal Life
(Elsevier BV, 2013)
Multiple eukaryotic clades make their first appearance in the fossil record between ~810 and 715 Ma. Molecular clock studies suggest that the origin of animal multicellularity may have been part of this broader eukaryotic ...
Geobiology of a Lower Cambrian Carbonate Platform, Pedroche Formation, Ossa Morena Zone, Spain
(Elsevier BV, 2013)
The Cambrian Pedroche Formation comprises a mixed siliciclastic–carbonate succession recording subtidal deposition on a marine platform. Carbonate carbon isotope chemostratigraphy confirms previous biostratigraphic assignment ...
Microstructures in Metasedimentary Rocks from the Neoproterozoic Bonahaven Formation, Scotland: Microconcretions, Impact Spherules, or Microfossils?
(Elsevier BV, 2013)
Microscopic spherules in relatively undeformed mudstones of the Neoproterozoic Bonahaven Formation, Islay, Scotland, are differentiated from their matrix by a sharp micron-scale, smoothly rounded boundary. These elongate ...
The Meaning of Stromatolites
(Annual Reviews, 2013)
Stromatolites document microbial interactions with sediments and flowing water throughout recorded Earth history and have the potential to illuminate the long-term history of life and environments. Modern stromatolites, ...
Animals in a Bacterial World, A New Imperative for the Life Sciences
(Proceedings of the National Academy of Sciences, 2013)
In the last two decades, the widespread application of genetic and genomic approaches has revealed a bacterial world astonishing in its ubiquity and diversity. This review examines how a growing knowledge of the vast range ...
Oxygen, Ecology, and the Cambrian Radiation of Animals
(Proceedings of the National Academy of Sciences, 2013)
The Proterozoic-Cambrian transition records the appearance of essentially all animal body plans (phyla), yet to date no single hypothesis adequately explains both the timing of the event and the evident increase in diversity ...