The Geologic Time Scale - Cone-bearing plants (gymnosperms)...

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The Geologic Time Scale I. Precambrian Era (4600 – 543 million years ago) a. Earliest traces of life b. Oldest fossils of pro- and eukaryotic cells c. Oxygen begins to accumulate in atmosphere II. Paleozoic Era (543 – 245 million years ago) a. Cambrian Period i. Radiation of most modern animal phyla (Cambrian explosion) b. Ordovician Period i. Marine algae, plants and arthropods found on land c. Silurian Period i. First jawed fishes ii. Diversification of early vascular plants d. Devonian Period i. Diversification of bony fishes, first amphibians/insects e. Carboniferous Period i. Forests, first seed plants, origin of reptiles, amphibians dominant f. Permian Period i. Extinction of many marine and terrestrial organisms (Permian mass extinction) ii. Radiation of reptiles, origins of mammal-like reptiles and most modern insects III. Mesozoic Era (245 – 65 million years ago) a. Triassic Period i.
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Unformatted text preview: Cone-bearing plants (gymnosperms) ii. Dinosaurs originate b. Jurassic Period i. Dinosaurs abundant, diverse ii. Gymnosperms dominate landscape c. Cretaceous Period i. Flowering plants (angiosperms) appear ii. Many organisms (including dinosaurs) become extinct, (Cretaceous Extinction) IV. Cenozoic Era (65 million years ago present) a. Tertiary Period i. Paleocene epoch radiation of mammals, birds, pollinating insects ii. Eocene epoch Angiosperm dominance increases, continued radiation of most modern mammalian orders iii. Oligocene epoch origins of most primates, including apes iv. Miocene epoch continued radiation of mammals & angiosperms v. Pliocene epoch apelike ancestors of humans appear b. Quaternary Period i. Pleistocene epoch Ice age, humans appear ii. Recent Historical time...
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