Timeline: The history of the Earth

Period: 4570 BCE to 541 BCE

Precambrian

Guide fossils : Stromatolites (cianobacterias)
Climate event : Incresing of the salt in the sea , in consequence of the heavies precipitations.The first glaciation occurs and a oxigenated atmosphere is created.

Geological event : There was a big bombardement, the Earth, the moon and the litosphere was formed. Origin and early evolution of the Earth.
Marine enviorement.

541 BCE

Cambrian period

Pluricellular algae

Period: 511 BCE to 485 BCE

Palezoic

Guide fossils : Trilobites anthropoid .
Geological event : Hercinic orogeny, a lot of mountain ranges were formed.
Climate events : Greenhouse effect, hight volcanic activity, reduction of coastlines and marine platforms by the formation of the Pangeas super continent.
Continental enviroment.

485 BCE

Ordovician period

Main groups of invertebrates , fishes.

Period: 443 BCE to 419 BCE

Silurian period

Vegetables( gymnosperms, rootless, leafless, flowerless, reproduced by spores) and invertebrates.

Period: 419 BCE to 359 BCE

Devonian period

Amphibians

Period: 359 BCE to 299 BCE

Carboniferous period

Conifers, ferns and main reptiles.

Period: 299 BCE to 252 BCE

Permian

Amphibians and pelycosaurus.
Extinction of 90% of marine species and 70% of terrestrial species, caused by the heating of rocks

Period: 252 BCE to 66 BCE

Mesozoic

Guide fossils : Belemnites and Ammonites (cephalopod mollusk).
Geological events : It started to separate Pangea and the continents ,it was originated the Athlantic ocean and the Alpina orogenic.
Climate events : Climatic conditions of extreme aridity , most of all, inside Pangea, it is going to evolve to a tropical and humid climate.
Continental enviroment

Period: 66 BCE to 2021

Cenozoic

Guide fossils : Nummulites.
Geological events :Complete development of the Alpine orogeny, the isthmus of Panama is formed 3am ago. Formulation of the current polar caps.
Climate events : Colder and warmer periods called glacial and interglacial periods.