Unformatted text preview: 460:206:01 DINOSAURS Major Unifying Theories Basic Concepts
unifying theories Evolution Plate Tectonics Plate Tectonics: large segments of the outer part of the Earth (lithospheric plates) move relative to one another over the athenosphere (viscous fluid) Alfred Wegner- Father of Continental Drift Alfred Wegner- Father of Continental Drift Theory of Continental Drift mechanism: low density continents “floating” on higher density ocean floor rocks and “sailing” through them Plate Tectonics
Continental Drift was thrown out and the Theory of Plate Tectonics was born. Evidence for Plate Tectonics Evidence for Plate Tectonics Evidence for Plate Tectonics Evidence for Plate Tectonics What evidence supported Wegener’s What continental drift hypothesis?
1. Obvious fit of continents Obvious 2. Paleoclimate data (glaciers, climate belts) Paleoclimate 3. Similar fossils separated by oceans Similar 4. Rock type and structural similarities Rock Evidence for Plate Tectonics What evidence did What Wegener use? Wegener 1. Obvious fit of continents continents Pangaea
250 Ma now
W. W. Norton. Modified from Wegener A, The Origin of the Continents and Oceans. The What other evidence did Wegener use? Glacial striations Glacial •Evidence for distribution of glaciers Glaciation
(260-280 Ma) striations-direction till deposits-perimeter If continents If were connected, were one large ice cap one explains record Support for Plate Tectonics Support Climate belts seem to match across continents Climate seem Equator Support for Plate Tectonics 3. Distribution of fossils …similar fossils …oceans apart Mesosaurus Mesosaurus freshwater reptile freshwater lived ~286 Ma lived Support for Continental Drift Distribution of fossils Support for Plate Tectonics 4. Alignment of ancient mountain belts & rock types mountain What evidence supported Wegener’s What Plate Tectonics?
1. Obvious fit of continents Obvious 2. Paleoclimate data (glaciers, climate belts) Paleoclimate 3. Similar fossils separated by oceans Similar 4. Rock type and structural similarities Rock Components of Plate Tectonics Components of Plate Tectonics Components of Plate Tectonics Components of Plate Tectonics What is Life? HIV virus Chicken Pox Prokaryotes Eukaryotes Kingdom Monera Kingdom Protista Kingdom Fungi Kingdom Plantae Kingdom Animalia Evolution
• We observe that life has changed through time. • Thus EVOLUTION is a fact, based on empirical observation, not a theory. • Life has not remained the same throughout all of geologic time, and there have been several phases of life/ecosystems. Evolution
• Example of Peppered Moths during the Industrial Revolution. • Rise of the black bodied moths due to environmental changes. PHASE I: The Cambrian Marine Ecosystem PHASE II: The Paleozoic Marine Ecosystem PHASE III: The Modern Marine Ecosystem The Big Five Mass Extinctions The Big Five Mass Extinctions The end-Permian mass extinction “The Great Dying” The end-Ordovician mass extinction The Late Devonian mass extinction The end-Triassic mass extinction The end-Cretaceous mass extinction 5 2 3 14 II I III 5 2 3 14 II I III After the end-Triassic mass extinction After the end-Cretaceous mass extinction ...
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- Spring '11
- Plate Tectonics, Alfred Wegener, Evolution Plate Tectonics