Cambrian 570M-500M

Cambrian 570M-500M

Feb 5, 1923

This spirit is the earliest record of Marine life, and Trilobites are dominant.

Ordovician 500M-435M

Feb 5, 1934

Invertebrates are dominant, mollusks become abundant. Earliest fish that are jawless and later, jawed and armored fish.

Silurian 435M-395M

Feb 5, 1941

The earliest terrestrial plants and animals , Tiktaalik Eurypterids develop.

Devonian 395M-345M

Feb 5, 1950

Armored fish go extinct, but abundance of several species of fish. the earliest amphibians and ammonites.

Carboniferous 345M-280M

Feb 5, 1961

Abundant sharks and amphibians. Large swamps and coal forming forests.

Permian 280M-225M

Feb 5, 1971

The extinction of many types of marine animals including trilobites.

225M-195M Triassic

Feb 5, 1976

Earliest Dinosaurs, abundant cycads and conifers.

195M-136M

Feb 5, 1986

Earliest birds and mammals abundant dinosaurs and ammonites.

136M-65M Cretaceous

Feb 5, 1999

Earliest flowering plants, climax of dinosaurs followed by their extinction.

65M-1.8M Tertiary

Feb 5, 2010

Earliest placental mammals modern mammals large running mammals.

1.8M-Present Quaternary

Feb 5, 2011

Large Carnivores that involve Humans and Neanderthals.