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olga2289 [7]
3 years ago
11

Scientists infer that oxygen first began to enter the Earth's atmosphere after the appearance of

History
1 answer:
Vinil7 [7]3 years ago
5 0

Oxygen entered the Earth's atmosphere after the appearance of the Great Oxidation Event (Great Oxygenation Event). The Great Oxidation is the first mass extinction on Earth.

The Great Oxidation lasted 2.4 to 2.0 billion years ago.

Oxygen appeared on Earth thanks to cyanobacteria using photosynthesis.

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