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Geological Time Scale in Terms of the Twelve Hour Clock

Topic Age When(Ma) Time
Earth's Formation   4600 12:00
First Rocks Archean 3800 2:05
Single-Celled Organisms Archean 3600 2:36
Shellfish Early Cambrian 540 10:36
Fish Ordovician 480 10:45
Land Plants Late Silurian 410 10:55
Insects Devonian 400 10:57
Amphibians Devonian 370 11:02
Reptiles Carboniferous 340 11:07
Conifers Carboniferous 320 11:10
Dinosaurs Late Triassic 230 11:23
Mammals Late Triassic 210 11:27
Birds Late Jurassic 145 11:37
Flowering Plants Early Cretaceous 125 11:40
Last Dinosaurs Late Cretaceous 65 11:50
Grass Miocene 25 11:56
Humans Holocene 3 11:59

   

    Last Modified: 2004-12-10