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Paleobiogeography. Biogeography (ENVR333) Fall 2007 5 October 2006. PaleoBiogeography. Time Scale Theory of Continental Drift and Plate Tectonics The Breakup of Pangea Biogeographic Implications of a Dynamic Geography. Geologic Time Scale. (Fig 7.1 MacDonald 2003).
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Paleobiogeography Biogeography (ENVR333) Fall 2007 5 October 2006
PaleoBiogeography • Time Scale • Theory of Continental Drift and Plate Tectonics • The Breakup of Pangea • Biogeographic Implications of a Dynamic Geography
Geologic Time Scale (Fig 7.1 MacDonald 2003)
Theory of Continental Drift • Alfred Wegener (1880-1930) • 1915 The Origin of Continents and Oceans • Pangea = supercontinent
Evidence for Continental Drift Glacial deposits Matching shapes Similar rock types and structures Continuity of plant and animal fossils
Plate Tectonics Fig 7.5 MacDonald 2003)
connectivity Pangea 200 million km2 or 40% of earth’s surface
Break up of Pangea Laurasia Tethyan Seaway Gondwanaland
Cenozoic Changes India rafts into Asia (45 mya) Africa and Europe rejoin (17 mya) Stepping Stone Islands created (15 mya) Central American Landbridge (6mya) Epicontinental seas disappear
http://www.clearlight.com/%7Emhieb/WVFossils/continents.html
Biogeographic Implications Speciation
Biogeographic Implications Corridors and Barriers Great American Interchange
Biogeographic Implications Corridors and Barriers 12,000 ybp Beringia today
Biogeographic Implications Marine-Climate effects