The Hadean eon represents the time from which Earth first formed ... the gathering up of oxygen in Earth's atmosphere, and the Phanerozoic eon coincides with the major diversification of animals ...

T he Proterozoic Eon, spanning from 2,500 million to 539 million years ago, marked a transformative chapter in Earth's history.Often overshadowed by the more data-rich Phanerozoic Eon, this period ...