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Earliest Evidence of Life (3.8 billions years years ago):
The first microscopic life forms, likely single-celled prokaryotes, appeared. -
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Proliferation of Cyanobacteria (3.5 billions years years ago):
Cyanobacteria, or blue green algae, began producing oxygen via photosynthesis. -
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Evolution of Prokaryotic Cells (2.1 billions years ago)
Prokaryotes, simple single celled organisms, dominated early earth. -
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Formation of Earth’s Crust hand Ocean (4.5 billions years ago):
Description:The earth cooled forming a solid crust and liquid water, creating the first oceans. -
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First Fossil Evidence (3.5 billions years ago)
Stromatolites p, layered structures formed by Cyanobacteria, are the earliest fossil evidence of life.