Wednesday, September 19, 2012

Proterozoic Era

The Proterozoic is the second geological era in the time spans of Earth history. It stretched from about 1,500 to 600 million years ago. Being part of the Precambrian times, the Proterozoic is characterized by the abundance of first aquatic life forms, such as bacteria, fungi, algae and other primitive multicellular organisms. The great amount of bacteria and algae contributed to the build-up of oxigen in the atmosphere.