INTRO

The book that you are about to read is going talk about all of earths history,major events, and all four eras.

INTRO

The Pre Cambrian is going to talk about the first stages of earth and how it formed and the first living thing. The Paleozoic era is going to talk about Life evolving. The mass extinction of life and the super continent. In the Mesozoic era your going to learn on the new complex organisms, the mass extinction of the Dinosarus. In the Cenozoic era its going to talk about mammals,humans.

Chapter 1 Precambrian era

The Precambrian Era lasted 245 million years. The earth was just forming. Earth was forming from dust and rock. With the help of gravity it pulled all of the rock and dust together to make earth. meteors started to rain down on the earth constantly. earths surface was hotter then the sun. a earth size planet came crashing into breaking it a part. a lot of rocks flew but gravity pulled some and the moon was formed and was moving away from earth. earth was repaired. earth was cooling down but asteroids were falling down on earth. The asteroids were carrying water and singled celled organisms. The earth fully cooled down. Oceans were made and live was on earth

Chapter 1 Precambrian era

Earth had oceans but it was still very dangerous because the winds were very powerful. a few years later the first living organisms know as the Prokaryote was living underwater. The Prokaryote was releasing oxygen into earths atmosphere making earth habitable. Earth was cooling too fast and the temperature was freezing cold. The first ice age happened and earth was frozen. Earth froze for 11,700 years. earth was heating up and Volcanos started to pop out of the ground. All of the earths ice was melting. The Prokaryote was still alive after all those years.

Chapter 2 Paleozoic era

The Paleozoic era was the longest era. it lasted 245 million years. Life was evolving quickly.This era was known as the "Cambrian explosion" they named this because near the end of the era a mass extinction happened. 90% of marine life died and 70% of land life died. The first vertebrate animals roamed the land.

chapter 2 Paleozoic era

During this era the world was warm worldwide and there was two big continent. The two big continents collided and made up on big super continent called Pangea. this caused the Arthpod to evolve. Pangea made sea animals live on land.

Chapter 3 Mesozioc era

The Mesozoic era lasted 252 million years. This era had three different periods The Triassic,Jurrasic, And the Cretaceous. The Triassic period was the first period in the Mesozoic era there was not a lot of living things because of the mass extinction from the previous era but after a few years everything changed after life was every where. the Jurrasic period or know as the "age of reptiles" this period was know for Dinosarus because there were only Dinosarus. In the sea there were big sea Dinosarus roaming the sea. The Cretaceous period was the last period in the Mesozioc era this period was the longest out of the three. A giant Astroid hit earth and killed all of the Dinosarus.