Era

Period

Epoch

Comment

Cenozoic

Quaternary

Holocene

Following extinction of dinosaurs mammals replace reptiles as the dominant land animal species.

Development of human species. 2 million years duration

Pleistocene

Tertiary

Pliocene

63 million year period

Miocene

Oligocene

Eocene

Paleocene

Mesozoic

Pliocene

Dinosaurs, first birds and first flowering plants

Cretaceous

Jurassic

Triassic

Paeozoic

Permian

First organisms with shells, first fish, insect and towards the end of the era, the first reptiles and abundant amphibians

Carboniferous

Devonian

Silurian

Ordovician

Cambrian

Precambrian

Dates to the time between when Earth was first formed and when the first forms of complex life appeared (approximately 88% of all geological time) - first single celled and then multi celled organisms.