how did life on earth form
Clouds formed as the Earth began to cool, producing enormous volumes of rainwater that formed the oceans. For the next 1.3 billion years (3.8 to 2.5 billion years ago), the Archean Period, first life began to appear and the worldâs landmasses began to form. Earthâs initial life forms were bacteria, which could survive in the highly toxic atmosphere that existed during this time.