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