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"How could life originate multiple times and then rapidly diversify in such a short amount of time?"
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Iron Isotope Record Reflects Microbial Metabolism Through Time
NAI’s University of Wisconsin team presents a review of iron isotope fingerprints created through biogeochemical cycling in the May, 2008 issue of Annual Review of Earth and Planetary Sciences. This landmark paper brings together for the first time the co-evolution records of photosynthesis, bacterial sulfate reduction, and bacterial iron reduction in the early Earth. They review data on natural systems and experiments, looking at both abiological and biological processes, and conclude that the temporal carbon, sulfur, and iron isotope record reflects the interplay of changing microbial metabolisms over Earth’s history.
![Recent Articles](https://webarchive.library.unt.edu/eot2008/20080922001920im_/https://astrobiology.nasa.gov/img/text/hd_recent_mb.gif)
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- Early Earth Primed for Later RNA and DNA Production
- Molecules in the Atmospheres of Extrasolar Planets - A Workshop in Paris
- Cyanobacterial Biomarkers in Ancient Rocks
- Evolution of the Gut
- Jill Tarter and Will Wright Talk Gaming, Education, and Evolution in Seed Magazine's Video 'Salon'
- NASA Chooses MAVEN as the Next Mars Scout Mission
- NASA's Carl Sagan Fellows to Study Extraterrestrial Worlds
- Looking for Life on Mars in a Canadian Lake
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