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The only reason the Earth has enough oxygen to "support life" is because life produced it as a waste product. https://en.wikipedia.org/wiki/Great_Oxygenation_Ev
by User23 8y ago
The only reason the Earth has enough oxygen to "support life" is because life produced it as a waste product. https://en.wikipedia.org/wiki/Great_Oxygenation_Event https://en.wikipedia.org/wiki/Great_Oxygenation_Event