‘When the Earth first formed, the sun was dimmer than it is now. Despite this, our planet was very hot because the levels of methane and carbon dioxide were very high. Then, when cyanobacteria evolved and consumed almost all of these two greenhouse gases, temperatures dropped to the point that the Earth froze over into a solid chunk of ice. It stayed that way for tens of millions of years until volcanic action managed to eventually release enough CO2 into the atmosphere that the greenhouse effect freed the planet.’
Related postings:
Cyanobacteria, the Game Changer
https://samslair.blogspot.com/search?q=Cyanobacteria&m=1
Snowball Earth:
