HISTORY OF THE EARTH

HADEAN EON

• Began 4.5 bya and ended 3.9 bya
• Hellish
• The formation of earth was happening during this time.
• According to ucmp.berkeley.edu, During Hadean time, the Solar System was forming, probably within a large cloud of gas and dust around the sun, called an accretion disc. The relative abundance of heavier elements in the Solar System suggests that this gas and dust was derived from a supernova, or supernovas — the explosion of an old, massive star.

NEXT CAME THE..

ARCHEAN EON

• Began 3.9 bya and ended 2.5 bya
• This eon was where early signs of life started. Such as stromatolites.

NEXT

PROTEROZOIC EON

• Began 2.5 bya and ended 600 mya
• This was the eon where animals started to evolve.
• Stromatolites became more popular around the earth.
• Fossils became known because of all of the bacteria.

THEN

PALEOZOIC ERA

• Began 600 mya and ended 250 mya
• The Cambrian period - "Cambrian explosion"of all animals and skeletons. Also the first vertebrates came in the middle of the Cambrian era.
• The Ordovician period - first land plants.
• The Silurian period- first jawed fish.
• The Devonian period - insects, seeded plants and first land vertebrates.
• The Mississippian period - reptiles.
• The Pennsylvanian period - winged insects.
• The Permian period - largest mass extinction.

LATER

MESOZOIC ERA

• Began 250 Mya and ended 70 mya
• Triassic - first dinosaurs,early mammals and Pangaea begins break up.
• Jurassic - first birds.
• Cretaceous - extinction of dinosaurs.

NEXT

CENOZOIC ERA

• Began 70 mya to present.
• Paleocene - mass extinction
• Eocene - modern mammals form
• Oligocene - according to ucmp.berkeley. Edu, In the oceans, marine biotic provinces became more fragmented as sea dwellers capable of withstanding cooler temperatures congregated to places further from the warmer equator
• Miocene - grass lands
• Pliocene - vegetation and savannas form
• Pleistocene - everything was starting to take its place such as animals, terrain,climate,etc.
• Holocene - Look around you, we are in the Holocene.

WORK CITED

• http://www.daviddarling.info/encyclopedia/C/Cenozoic.html
• http://www.ucmp.berkeley.edu/precambrian/archean_hadean.php
• Science book
• http://www.slideserve.com/niyati/proterozoic-eon-2-5-bya-570-mya
• http://slideplayer.com/slide/5294333/