The breathable air we enjoy today originated from tiny organisms, although the details remain lost in geologic time…
https://www.scientificamerican.com/article/origin-of-oxygen-in-atmosphere/
RESTORING A COOL GREEN PLANET
The breathable air we enjoy today originated from tiny organisms, although the details remain lost in geologic time…
https://www.scientificamerican.com/article/origin-of-oxygen-in-atmosphere/