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
Matching shapes
Similar rock types and structures
Continuity of plant and animal fossils
Glacial deposits
Plate Tectonics
Fig 7.5 MacDonald 2003)
Plate Tectonics
Pangea
200 million km2 or 40% of earth’s surface
connectivity
Break up of Pangea
Laurasia
Gondwanaland
Tethyan Seaway
Break up of Pangea
Cenozoic ChangesIndia 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 ImplicationsSpeciation
Biogeographic Implications
Corridors and Barriers
Great American Interchange
Biogeographic Implications
Corridors and Barriers
12,000 ybp
today
Beringia
Biogeographic ImplicationsMarine-Climate effects