1. BIOLOGY CONCEPTS & CONNECTIONS Fourth Edition Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Neil A. Campbell Jane B. Reece Lawrence G. Mitchell Martha R. Taylor From PowerPoint ® Lectures for Biology: Concepts & Connections CHAPTER 15 Tracing Evolutionary History Modules 15.1 – 15.5

2. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Did birds evolve from dinosaurs? Evolutionary biologists investigate this question by looking at the fossil record Are Birds Really Dinosaurs with Feathers?

3. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The fossil of the earliest known bird, Archeaopteryx, was discovered in 1861 Fossils of dinosaurs with feathers may support the bird- dinosaur theory

4. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Macroevolution consists of the major changes in the history of life –The fossil record chronicles these changes, which have helped to devise the geologic time scale 15.1 The fossil record chronicles macroevolution EARTH HISTORY AND MACROEVOLUTION

5. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 15.1

6. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The sequence of fossils in rock strata indicates the relative ages of different species Radiometric dating can gauge the actual ages of fossils 15.2 The actual ages of rocks and fossils mark geologic time

7. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Continental drift is the slow, incessant movement of Earth’s crustal plates on the hot mantle 15.3 Continental drift has played a major role in macroevolution Figure 15.3A Pacific Plate North American Plate Nazca Plate South American Plate African Plate Eurasian Plate Split developing Indo-Australian Plate Edge of one plate being pushed over edge of neighboring plate (zones of violent geologic events) Antarctic Plate

8. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings This movement has influenced the distribution of organisms and greatly affected the history of life –Continental mergers triggered extinctions –Separation of continents caused the isolation and diversification of organisms Figure 15.3B Millions of years ago Eurasia CENOZOIC MESOZOIC PALEOZOIC North America Africa India South America Antarctica Australia Laurasia Gondwana Pangaea

9. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Continental drift explains the distribution of lungfishes –Lungfishes evolved when Pangaea was intact Figure 15.3C

10. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 15.3D NORTH AMERICA SOUTH AMERICA EUROPE AFRICA ASIA AUSTRALIA = Living lungfishes = Fossilized lungfishes

11. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Plate tectonics, the movements of Earth’s crustal plates, are also associated with volcanoes and earthquakes –California’s San Andreas fault is a boundary between two crustal plates 15.4 Connection: Tectonic trauma imperils local life Figure 15.4A San Andreas fault San Francisco Santa Cruz Los Angeles

12. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings By forming new islands, volcanoes can create opportunities for organisms –Example: Galápagos But volcanic activity can also destroy life –Example: Krakatau Figure 15.4B, C

13. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings At the end of the Cretaceous period, many life- forms disappeared, including the dinosaurs –These mass extinctions may have been a result of an asteroid impact or volcanic activity 15.5 Mass extinctions were followed by diversification of life-forms

14. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 15.5 90 million years ago807065 Cretaceous extinctions 60 ?

15. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Every mass extinction reduced the diversity of life –But each was followed by a rebound in diversity –Mammals filled the void left by the dinosaurs