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The Mesozoic Era: Jurassic and Cretaceous
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 The Jurassic has become famous in our time thanks to the cinema. Splendor was the era of the dinosaurs, when they ruled the earth.
Although less famous, the Cretaceous is a crucial period in the geological history of Earth. We'll see why.
Splendor and end of the dinosaurs
The Jurassic ranges from about 213 to 144 million years ago and takes its name from the rock strata of the Jura mountains. It is characterized by the hegemony of the great dinosaurs and the Pangea split into the continents North America, Eurasia and Gondwana. Of the latter split Australia (in the Late Jurassic and early Cretaceous), giving rise to new species of mammals
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Geological history: the Mesozoic
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 This was intermediate lasted about 160 million years. In the beginning all the continents, or islands, the previous period were assembled into a single giant continent called Pangea that is, the whole Earth.
The major folding occurred in the west side of America, the Rocky Mountains in the north and the Andes in the South.
The weather remained warm, but somewhat dry. The Earth was dominated by large conifers as they look, from space, should be much greener than today. :-( (The animals appeared and, finally, the famous dinosaurs became extinct.
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The Paleozoic: Devonian, Carboniferous and Permian
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 The Devonian period, which began 408 million years ago, is characterized by the appearance of several types of fish, ranging sharks dipnoos, armored fish, and a primitive form of fish with hard scales, which probably evolved from ancestors amphibians.
There were corals, starfish, sponges and trilobites, and the first insect known. Woody plants were developed, and late Devonian, as did other land plants such as ferns and seed ferns, horsetails and trees associated with current squamous Selago. There are forest.
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Geological history: the Paleozoic
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This was old lasted about 315 million years. The planet was very different than today. The land surface had the appearance of islands about Ecuador disperse around Earth. Some of these islands were South America, Laurentia and Gondwana.
During this time there were many folds. The weather was still warm and humid. This encouraged the proliferation of multicellular organisms and their subsequent evolution.
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Geological history: the Precambrian
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This lengthy period of Earth's history spans from its formation, about 4,500 million years ago to about 580 million years, or nearly 4,000 years of history of the planet. It occupies 88% of Earth history. Much seems.
Well, not everyone agrees. Some authors call "Azo" the period when the Earth was still forming and put the start of the Precambrian about 3,800 million years ago, when the crust was already (more or less) consolidated and began to form the first organic substances . Similarly, others place the end of the period between 590-540 million years ago, when the first algae.
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