Historical event

First Cyanobacteria

Date: about 3.5 Billion Years Ago

Appearance of cyanobacteria (blue-green algae), the first organisms to produce oxygen through photosynthesis, profoundly changing Earth's atmosphere.

Tags: cyanobacteria, blue-green algae, photosynthesis, oxygen, great oxygenation event, evolution, stromatolites, early life

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