3.5 bya
4.5 bya
3.4 bya
10,500 ya
2.4 mya
4.1 bya
700 mya
4.6 bya
450 mya
1804
200,000 ya
2.1 bya
Evidence of life
First eukaryotic cells
Moon formed
Ozone sufficient for land organisms
First photosynthetic organisms (O2 accumulates)
Homo sapiens
World population 1 billion
Multicellular organisms
Homo appears
First prokaryotic cells
Earth formed
Agriculture