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Period: to
Precambrian Time
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first crustal rocks form.
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Earths surface is cool enough for liquid water
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first known unicellular life appears
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Earths atmoosphere starts to become oxygen rich
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first known multicellular life appears
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first fungi appear
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First shelled organisms such as arthopods and mollusks appear
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Period: to
The Paleozoic Era
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First possible vertebrates appear
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Modern, oxygen-rich atmosphere has formed
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First known unicellular life appears
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First anthropods, amphibians, and reptiles appear.
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Formation of pangea is complete.
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Permian mass extinction results from major enviornmental changes
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Period: to
The Mesozoic Era
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Pangea begins to break apart
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The last dinosaurs become extinct. catastrophic metorite impact occurs
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Period: to
The Cenozoic era
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Most modern mammal families, including whales, carnivores, hoofed animals, primates, and first grasses appear.
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india collides with asia, and antartica drifts over the south pole
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First hominids(early human ansestors) appear.
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modern ice age begins
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modern humans appear
