Evolution of the Atmosphere
History of Márcio Farias - Viseu, Portugal
The Earth was an uninhabitable place with no breathable air for hundreds of millions of years after its formation. Over time, however, it developed an atmosphere that was quite different from the one we know today. The primitive atmosphere was composed of methane, ammonia, hydrogen, nitrogen, carbon dioxide and water vapour, but there was no oxygen.
Oxygen only appeared in the atmosphere due to its release by living beings, namely through photosynthesis. The first photosynthetic beings were not plants or algae, as they did not yet exist. The first living beings to carry out photosynthesis and release oxygen into the atmosphere were microorganisms similar to today's bacteria that began to appear in the primitive oceans, more than 3,000 million years ago.
Oxygen only appeared in the atmosphere due to its release by living beings, namely through photosynthesis. The first photosynthetic beings were not plants or algae, as they did not yet exist. The first living beings to carry out photosynthesis and release oxygen into the atmosphere were microorganisms similar to today's bacteria that began to appear in the primitive oceans, more than 3,000 million years ago.