Life's expanding realm

Knoll, A.

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NASA NTRS · 20040089699

Life's expanding realm

Knoll, A.

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Abstract

Geologic sediments from the Nullagine Range in Australia are used to illustrate the early existence of microbial communities in the oceans. These communities survived in oxygen-free environments. Some microbes, particularly cyanobacteria, developed the ability to synthesize energy from light, which led to the evolution of creatures with oxygen-dependent metabolism. Only recently has geologic evidence been discovered that supports the theory that animals developed only when there was enough oxygen in the atmosphere to support higher forms of life.

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Non-NASA Center NASA Discipline Exobiology Cyanobacteria/metabolism/physiology Fossils Oxygen/analysis/metabolism Water Microbiology Evolution Marine Biology Earth (Planet)Paleontology Photosynthesis/physiology Australia Geologic Sediments/analysis/microbiology Atmosphere/analysis

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Knoll, A.. 1994-06-01. Life's expanding realm. https://ntrs.nasa.gov/citations/20040089699

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