| Eon | Eras | Periods | Epochs | Age (beginning) | notes |
|---|
|
| Phanerozoic | Cenozoic | Quaternary | Holocene (Recent) | 10000 years | End of Ice Age |
| Pleistocene | 1.8 Ma | |
| Tertiary | Pliocene | 5 Ma | |
| Miocene | 24 Ma | |
| Oligocene | 34 Ma | |
| Eocene | 55 Ma | |
| Palaeocene | 65 Ma | Mass extinction: dinosaurs, pterosaurs, and ammonites extinct |
| Mesozoic | Cretaceous | 141 Ma | Angiosperm plants, Mesozoic reptiles peak |
| Jurassic | 205 Ma | Ferns, cycads, ginkgos, ammonites |
| Triassic | 215 Ma | Molluscs and reptiles dominant, dinosaurs, ichthyosaurs |
| Palaezoic | Permian | 298 Ma | Trilobites extinct, Amphibians and reptiles dominant land animals |
| Carboniferous | 354 Ma | Foraminiferans, corals, bryozoans, brachiopods, amphibians become more common |
| Devonian | 410 Ma | Corals, brachiopods, ammonoids, crinoids, fishes and early land plants |
| Silurian | 434 Ma | primitive fish |
| Ordovician | 490 Ma | Graptolites dominant, also trilobites, brachiopods, bryozoans, gastropods, bivalves, echinoids, crinoids, |
| Cambrian | 545 Ma | Marine animals with mineralized shells appear: trilobites, echinoderms, brachiopods, molluscs, primitive graptolites, a variety of worms |
| Proterozoic | Precambrian | | Vendian | ~2500 Ma | 1st multi-celled organisms |
| Archean | | ~4000 Ma | The evolution of life, 1st one-celled organisms |
| Priscoan | | ~4600 Ma | The formation of the Earth's crust, Approx age of oldest rocks 3,800 Ma |
