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 ...

Earliest animals evolved in the mid to late Proterozoic Eon and lie deep in the fossil record. Please give special attention to the photo credit, as it is from a participating researcher not from ...

The subsequent Archean eon (approximately 3,500 million years ago) is known as the age of bacteria and archaea. The Proterozoic eon was the gathering up of oxygen in Earth's atmosphere ...

The Hadean eon represents the time before a reliable (fossil) record of life; it began with the formation of the planet and ended 4.0 billion years ago. The following Archean and Proterozoic eons ...

During the Proterozoic era, oxygen produced by photosynthesizing bacteria collects in the oceans and then in the atmosphere. Iron present in exposed rocks reacts with this oxygen, and rust colors ...