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