Phanerozoic Eon Mesozoic Era Permian extinction marks boundary between

Phanerozoic eon mesozoic era permian extinction marks

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Phanerozoic Eon: Mesozoic Era Permian extinction marks boundary between Paleozoic and Mesozoic eras The Age of Dinosaurs: Its rise and fall Consistently hot climate and dry terrestrial environments, little if any ice caps at poles
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Phanerozoic Eon: Mesozoic Era: Triassic Period 248-206 mya Reptiles plentiful: crocodiles and turtles First dinosaurs First true mammals Gymnosperms dominant land plant Volcanic eruptions led to global warming and mass extinctions near the end Phanerozoic Eon: Mesozoic Era: Jurassic Period 206-144 mya Gymnosperms continued to be dominant Dinosaurs dominant land animal Some attained enormous size First known bird Mammals present but not prevalent Phanerozoic Eon: Mesozoic Era: Cretaceous Period 144-65 mya Dinosaurs still dominant on land Earliest flowering plants, angiosperms Another mass extinction at the end of the period Dinosaurs (except birds) and many other species died out Large meteorite/asteroid or volcanic eruptions blamed The Cretaceous Mass Extinction Likely meteorite impact at 65.5 mya, Mesozoic/Cenozoic boundary Organisms that went extinct include about half of all marine species and many terrestrial plants and animals, including most dinosaurs The presence of iridium in sedimentary rocks suggests a meteorite impact about 65 million years ago Dust clouds caused by the impact would have blocked sunlight and disturbed global climate Phanerozoic Eon: Cenozoic Era Spans most recent 65 million years
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Tropical conditions replaced by a colder, drier climate Sometimes called The Age of Mammals Amazing diversification of birds, fish, insects, and flowering plants Phanerozoic Eon: Mesozoic Era: Tertiary Period • 65-1.8 mya • Mammals that survived expanded rapidly • Birds and terrestrial insects diversified • Angiosperms become the dominant land plant • Fish diversified, sharks become abundant • Whales appeared • Hominids appeared about 7 mya Phanerozoic Eon: Mesozoic Era: Quaternary Period 1.8 mya to present Periodic ice ages cover much of Europe and North America Widespread extinction of many species Certain hominids become more human-like Homo sapiens appear 130,000 years ago
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  • Fall '09
  • Extinction event, Cretaceous–Tertiary extinction event, Phanerozoic Eon

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