Early Earth, Page 20: [Previous Page] [Next Page] [Class Home Page] Textbook pages 54 - 71
EON ERA PERIOD EPOCH DATES AGE of
Phanerozoic Cenozoic Quaternary Holocene 0-2 Mammals Humans
Pleistocene
Tertiary Neogene Pliocene 2-5
Miocene 5-24
Paleogene Oligocene 24-37
Eocene 37-58
Paleocene 58-66 Extinction of dinosaurs
Mesozoic Cretaceous 66-144 Reptiles Flowering plants
Jurassic 144-208 1st birds/mammals
Triassic 208-245 First Dinosaurs
Paleozoic Permian 245-286 Amphibians End of trilobites
Carboniferous Pennsylvanian 286-320 First reptiles
Mississippian 320-360 Large primitive trees
Devonian 360-408 Fishes First amphibians
Silurian 408-438 First land plant fossils
Ordovician 438-505 Invertebrates First Fish
Cambrian 505-570 1st shells, trilobites dominant
Proterozoic Also known as Precambrian 570-2,500 1st Multicelled organisms
Archean 2,500-3,800 1st one-celled organisms
Hadean 3,800-4,600 Approx age of oldest rocks 3,800

Note: Dates are in millions of years
Reference: Graham R. Thompson, Jonathan Turk, Modern Physical Geology, Saunders College Publishing