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Early Archean fossil bacteria and biofilms in hydrothermally-influenced sediments from the Barberton greenstone belt, South Africa
Abstract SEM imaging of HF-etched, 3.3–3.5 Ga cherts from the Onverwacht Group, South Africa reveals small spherical (1 μm diameter) and rod-shaped structures (2–3.8 μm in length) which areExpand
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Multiplication of microbes below 0.690 water activity: implications for terrestrial and extraterrestrial life.
Since a key requirement of known life forms is available water (water activity; aw ), recent searches for signatures of past life in terrestrial and extraterrestrial environments have targeted placesExpand
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Implications of in situ calcification for photosynthesis in a ~3.3 Ga-old microbial biofilm from the Barberton greenstone belt, South Africa
Timing the appearance of photosynthetic microorganisms is crucial to understanding the evolution of life on Earth. The ability of the biosphere to use sunlight as a source of energy (photoautotrophy)Expand
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Darwin--a mission to detect and search for life on extrasolar planets.
The discovery of extrasolar planets is one of the greatest achievements of modern astronomy. The detection of planets that vary widely in mass demonstrates that extrasolar planets of low mass exist.Expand
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Polymeric substances and biofilms as biomarkers in terrestrial materials: Implications for extraterrestrial samples
Organic polymeric substances are a fundamental component of microbial biofilms. Microorganisms, especially bacteria, secrete extracellular polymeric substances (EPS) to form slime layers in whichExpand
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Biogenic Opal and Carbonate Accumulation Rates in the Subantarctic South Atlantic: The Late Neogene of Meteor Rise Site 704
A preliminary composite depth section was generated for Site 704 by splicing Holes 704A and 704B together over the interval 0-350 mbsf (0-9 m.y.). High-resolution carbonate and opal data from theExpand
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The simulated silicification of bacteria--new clues to the modes and timing of bacterial preservation and implications for the search for extraterrestrial microfossils.
Evidence of microbial life on Earth has been found in siliceous rock formations throughout the geological and fossil record. To understand the mechanisms of silicification and thus improve our searchExpand
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Report of the COSPAR Mars Special Regions Colloquium
Abstract In this paper we present the findings of a COSPAR Mars Special Regions Colloquium held in Rome in 2007. We review and discuss the definition of Mars Special Regions, the physical parametersExpand
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Morphologic and spectral investigation of exceptionally well-preserved bacterial biofilms from the Oligocene Enspel formation, Germany
Abstract The fossilised soft tissues of a tadpole and an associated coprolitic structure from the organic-rich volcanoclastic lacustrine Upper Oligocene Enspel sediments (Germany) were investigatedExpand
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