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