Geologic History of the Earth

ERA
Period
End Date (millions of years ago)
Notes
None
580

Earth's history begins, first life forms in the sea; first prokaryotes appear, then the first eukaryotes appear.

Paleozoic

Cambrian

Ordovician

Silurian

Devonian

Carboniferous

Permian

500
430
400
345
285
245

Age of invertebrates

First fish appear ( jawless fish)

Age of fish, first land plants appeared, first land arthropods

First amphibians, insects developed.

First reptiles, ice covered a large part of the earth, great coal forming forests.

Major extinctions occurred, first cone bearing plants and ferns.

Mesozoic

Triassic

Jurassic

Cretaceous

195
135
65

Age of Reptiles. First dinosaurs, first mammals

Rocky mountains rise, first birds, largest dinosaurs thrive.

First flowering plants, dinosaurs die out, first placental mammals.

Cenozoic

Tertiary

Quaternary

55
recent

Age of Mammals Primitive apes, ancient humans.

Humans are the dominant organism.