Content with the tag: “molecular fossils”
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Molecular Fossil Records
Some of the final stages of molecular fossil formation of a sterane, ergostane.Among the various geochemical proxies for the presence of molecular oxygen in the environment, molecular fossils offer a unique record of oxygen where it was first produced and consumed by biology: in sunlit aquatic habitats. Steroid biosynthesis requires molecular oxygen, making the study of sterane molecular fossils important in reconstructing early environmental conditions. In a new study, NAI-funded scientists and their colleagues present evidence that mircroaerobic marine environments where steroid biosynthesis was possible could have been widespread and persistent for long periods of time prior to the earliest evidence for atmospheric oxygen. Their study...
Source: [PNAS]
September 19, 2011 / Posted by: Daniella Scalice
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