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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 ...
Covariance of Microfossil Assemblages and Microbialite Textures Across an Upper Mesoproterozoic Carbonate Platform
(Society for Sedimentary Geology, 2013)
Early diagenetic chert nodules and beds in the upper Mesoproterozoic Angmaat (formerly Society Cliffs) Formation, Baffin and Bylot islands, preserve microfossils and primary petrofabrics that record microbial mat deposition ...
Paleobiological Perspectives on Early Eukaryotic Evolution
(Cold Spring Harbor Laboratory Press, 2014)
Eukaryotic organisms radiated in Proterozoic oceans with oxygenated surface waters, but, commonly, anoxia at depth. Exceptionally preserved fossils of red algae favor crown group emergence more than 1200 million years ago, ...
Geobiology of the Late Paleoproterozoic Duck Creek Formation, Western Australia
(Elsevier, 2010)
The ca. 1.8 Ga Duck Creek Formation, Western Australia, preserves 1000 m of carbonates and minor iron formation that accumulated along a late Paleoproterozoic ocean margin. Two upward-deepening stratigraphic packages are ...
Non-Skeletal Biomineralization by Eukaryotes: Matters of Moment and Gravity
(Taylor & Francis, 2010)
Skeletal biomineralisation by microbial eukaryotes significantly affects the global biogeochemical cycles of carbon, silicon and calcium. Non-skeletal biomineralisation by eukaryotic cells, with precipitates retained within ...
Testate Amoebae in the Neoproterozoic Era: Evidence from Vase-shaped Microfossils in the Chuar Group, Grand Canyon
(Paleontological Society, 2000)
Vase-shaped microfossils (VSMs) occur globally in Neoproterozoic rocks, but until now their biological relationships have remained problematic. Exceptionally preserved new populations from the uppermost Chuar Group, Grand ...
Vase-shaped Microfossils from the Neoproterozoic Chuar Group, Grand Canyon: A Classification Guided by Modern Testate Amoebae
(Society of Economic Paleontologists and Mineralogists, 2003)
Vase-shaped microfossil (VSM) assemblages front early diagenetic carbonate nodules in >742 +/- 6 Ma black shales of the Chuar Group, Grand Canyon, provide evidence for affinities with testate amoebae. Not only are VSMs ...
Acritarchs and Microfossils from the Mesoproterozoic Bangemall Group, Northwestern Australia
(Paleontological Society, 1999)
Three microfossil assemblages occur in the Mesoproterozoic Bangemall Group (1625-1000 Ma) of northwestern Australia, each occupying a different environmental and taphonomic setting. In peritidal environments, benthic ...
Directionality in the History of Life: Diffusion from the Left Wall or Repeated Scaling of the Right?
(Elsevier, 2000)
Issues of directionality in the history of life can be framed in terms of six major evolutionary steps, or megatrajectories (cf. Maynard Smith and Szathmary 1995): (1) evolution from the origin of life to the last common ...