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  The Earth formed from planetary nebula. Oldest age-dated rocks on Earth. Fossil algae and strmatolites (prokaryotes). Fossil evidence of bacteria. Fossil evidence of cells with a nucleus (eukaryotes). First multi-celled organisms (seaweed and algae). Oldest marine worms and jellyfish.
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  First of 4 ice ages - 1 MYA. Oldest direct human- ancestor fossil, Homo habilis - 1MYA. First modern man, Homo sapiens - 0.1 MYA. Mammoth and mastodon bones - 0.5 MYA. Revolutionary War - 235 years ago. World War II - 70 years ago.
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  3900 million years ago.
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  Burgess Shale animals. Animals with a notochord.
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  First fish. First fossil evidence of land plants.
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  First vascular land plants. Oldest lung fish fossils.
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  Oldest fossil evidence of mosses. First insects. First lobe-finned fish. First land animals. First sharks. First seed plants.
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  First possible reptiles.
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  Permian system begins. Snail-backed reptiles (Dimetrodon). End of Paleozoic. 96% of all life on Earth perishes.
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  First crocodiles. First dinosaurs. First mammals (shrew like). First turtles,
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  Dilophosaurus, early dinosaur. First bird - Archeopteryx. Apatosaurus and Brachiosaurus. Stegosaurus.
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  First flowering plants, Duck-billed dinosaurs. Protoceratops. Triceratops. Tyrannosaurus rex. Velociraptor. End of Mesozoic, probably meteor or comet impact.
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  First ancestors of dogs and cats - 64 MYA. Grasses become widespread - 60 MYA. First ancestors of pigs and deer - 57 MYA. First horses - 55 MYA. First ancestors of rabbits - 45 MYA. First monkeys - 39 MYA. Oldest human like ancestors (hominids) - 4 MYA.
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