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"Will any of the planets of the solar system ever develop an atmosphere that will sustain life?"
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Cycling Nitrogen
NASA-funded researchers at the University of Washington have shown that microorganisms completed large-scale steps in the their evolution by 2.5 billion years ago. This means that the major branches of microbial life were before we have any record of them. One important aspect of this evolution was the development of microbes capable of fixing nitrogen. This metabolic pathway had profound effects on the environment of Earth and the evolution of all life on our planet.
Source: [Astrobiology Magazine]
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