Precambrian Major Events
There were many major events of the Precambrian period. First of all, the Sun and the Earth were created. The cyanobacteria used the sun’s energy through photosynthesis to make oxygen which made the oxygen-rich ozone layer formed which protected the Earth from radiation. Because of the cyanobacteria, oxygen levels also rose. Oceans were also created because after it rained, the rainwater collected in low areas which made the oceans and seas. Life also started in this period.