The History of Planet Earth

SECOND EDITION Earth’s Evolving The History of Systems Planet Earth

Ronald Martin, Ph.D. University of Delaware Newark, Delaware

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Library of Congress Cataloging-in-Publication Data Names: Martin, Ronald E. Title: Earth’s evolving systems : the history of planet Earth / Ronald Martin, PhD, University of Delaware, Newark, Delaware. Description: Second edition. | Burlington, Massachusetts : Jones & Bartlett Learning, [2018] | Includes index. Identifiers: LCCN 2016037413 | ISBN 9781284108293 Subjects: LCSH: Earth (Planet)—History. | Geodynamics—History. Classification: LCC QE501 .M2864 2018 | DDC 551.7—dc23 LC record available at https://lccn.loc.gov/2016037413

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9781284457162_FMxx_00i_xxii.indd 2 07/11/16 1:46 pm DEDICATION

This book is again dedicated to the late Dr. Allan Thompson (Department of Geological Sciences, University of Delaware), who did not shrink from learning something new and then teaching it. And to all those instructors who, like Al did, teach about the importance of the science of geology by transporting students to the other-worlds of Earth recorded in the rocks of geologic time.

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9781284457162_FMxx_00i_xxii.indd 3 07/11/16 1:46 pm BRIEF CONTENTS

PART I Earth Systems: Their Nature and Their Study ...... 1 CHAPTER 1 Introduction: Investigating Earth’s Systems ...... 3 CHAPTER 2 Plate Tectonics ...... 23 CHAPTER 3 Earth Systems: Processes and Interactions ...... 56 CHAPTER 4 Sedimentary Rocks, Sedimentary Environments, and Fossils .....85 CHAPTER 5 Evolution and Extinction ...... 113 CHAPTER 6 Geologic Time and Stratigraphy ...... 142

PART II The Precambrian: Origin and Early Evolution of Earth’s Systems ...... 167 CHAPTER 7 An Extraordinary Beginning: Hadean and Archean ...... 169 CHAPTER 8 Origins of Life ...... 200 CHAPTER 9 The Proterozoic: Life Becomes a Geologic Force ...... 225 CHAPTER 10 Life’s “Big Bang”: The Origins and Early Diversification of Multicellular Animals ...... 249

PART III The Phanerozoic: Toward the Modern World ...... 275 CHAPTER 11 The Early-to-Middle Paleozoic World ...... 277 CHAPTER 12 Late Paleozoic World ...... 328 CHAPTER 13 Mesozoic Era ...... 364 CHAPTER 14 The Cenozoic Era: The Paleogene Period ...... 421 CHAPTER 15 The Cenozoic Era: The Neogene Period ...... 456

PART IV Humans and the Environment ...... 499 CHAPTER 16 Rapid Climate Change During the Holocene ...... 501 CHAPTER 17 The Anthropocene: Humans as an Environmental Force ...... 524

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Preface to the Second Edition: For the Instructor and Student ...... xiii The Student Experience ...... xv Teaching Tools ...... xix Acknowledgments ...... xxi About the Author ...... xxii

PART I Earth Systems: Their Nature and Their Study ...... 1 CHAPTER 1 Introduction: Investigating Earth’s Systems ...... 3 1.1 Why Study the History of Earth? ...... 4 1.2 What Are the Major Earth Systems, and What Are Their Characteristics? ....7 1.3 Geologic Time and Process ...... 10 1.4 Directionality and the Evolution of Earth Systems...... 15 1.5 Geology as an Historical Science ...... 16 1.6 Method and Study of Earth’s Evolving Systems ...... 17 CHAPTER 2 Plate Tectonics ...... 23 2.1 Introduction ...... 24 2.2 Structure of Earth ...... 24 2.3 Plate Tectonics: From Hypothesis to Theory ...... 28 2.3.1 Early studies of mountain building ...... 28 2.3.2 Hypothesis of continental dri ...... 28 2.3.3 Hypothesis of seafloor spreading ...... 31 2.3.4 Corroboration of seafloor spreading...... 35 2.4 Continental Margins and Plate Boundaries: Features and Behavior ...... 37 2.4.1 Types of margins ...... 37 2.4.2 Tectonic features of Earth’s surface ...... 37 2.4.3 Types of plate boundaries ...... 40 2.5 Orogenesis ...... 45 2.5.1 Types of orogenesis ...... 45 2.5.2 Rocks and sediments associated with orogenesis ...... 46 2.6 Isostasy ...... 48 2.7 Tectonic Cycle ...... 48 2.8 Tectonic Cycle and Scientific Method ...... 51

9781284457162_FMxx_00i_xxii.indd 5 07/11/16 1:46 pm CHAPTER 3 Earth Systems: Processes and Interactions ...... 56 3.1 The Solid Earth System: Components and Processes ...... 57 3.2 Rock Cycle ...... 57 3.2.1 Igneous rocks ...... 57 3.2.2 Sedimentary rocks ...... 63 3.2.3 Metamorphic rocks ...... 63 3.3 Atmosphere and Its Circulation ...... 66 3.4 The Hydrosphere ...... 69 3.4.1 Hydrologic cycle ...... 69 3.4.2 Ocean circulation ...... 73 3.5 The Biosphere ...... 76 3.5.1 Biogeography: distribution of plants and animals over Earth’s surface ...... 76 3.5.2 Energy relationships ...... 76 3.5.3 Biogeochemical cycles ...... 77 3.6 The Tectonic Cycle and Earth Systems ...... 78 CHAPTER 4 Sedimentary Rocks, Sedimentary Environments, and Fossils .....85 4.1 Introduction to Sedimentary Rocks...... 86 4.2 Processes of Weathering ...... 86 4.3 Terrigenous Sedimentary Rocks ...... 88 4.3.1 Formation of terrigenous sediments ...... 88 4.3.2 What do terrigenous sedimentary rocks tell us about how they formed? ...... 88 4.4 Biogenic Sedimentary Rocks ...... 90 4.5 Chemical Sedimentary Rocks ...... 93 4.6 Marine Environments ...... 94 4.6.1 Marginal marine environments ...... 94 4.6.2 Coral reefs ...... 97 4.6.3 Continental shelves, continental slopes, and the abyss ...... 99 4.7 Sedimentary Structures ...... 105 4.8 Fossils ...... 105 4.8.1 Early processes of fossilization ...... 105 4.8.2 Modes of preservation ...... 108 CHAPTER 5 Evolution and Extinction ...... 113 5.1 Introduction ...... 114 5.2 Early Theories of Evolution ...... 114 5.3 Charles Darwin and the Beginnings of the Modern Theory of Evolution ...... 117 5.4 Basic Premises of Darwinian Evolution ...... 119 5.5 Inheritance and Variation ...... 121 5.6 Genetic Code and Mutation ...... 122 5.7 Evidence for Natural Selection ...... 123

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9781284457162_FMxx_00i_xxii.indd 6 07/11/16 1:46 pm 5.8 Speciation ...... 125 5.9 Evolution and the Fossil Record ...... 126 5.9.1 Comparative anatomy ...... 126 5.9.2 Cladistics ...... 126 5.9.3 Microevolution ...... 127 5.9.4 Macroevolution ...... 130 5.10 Mass Extinction ...... 134 5.11 Biodiversity Through the Phanerozoic ...... 137

CHAPTER 6 Geologic Time and Stratigraphy ...... 142 6.1 Introduction ...... 143 6.2 Relative Ages ...... 143 6.3 Absolute Ages ...... 143 6.4 Evolution of the Geologic Time Scale ...... 146 6.5 Correlation ...... 150 6.5.1 Lithocorrelation ...... 150 6.5.2 Formations and facies ...... 151 6.5.3 Biostratigraphy ...... 156 6.5.4 Integrating dierent stratigraphic datums ...... 158 6.6 How Complete Is the Geologic Record? ...... 158 6.6.1 Unconformities and diastems ...... 158 6.6.2 Sequence stratigraphy ...... 159 6.7 Why Is Sea Level So Important? ...... 162 PART II The Precambrian: Origin and Early Evolution of Earth’s Systems ...... 167 CHAPTER 7 An Extraordinary Beginning: Hadean and Archean ...... 169 7.1 Introduction ...... 170 7.2 Origin of the Universe ...... 170 7.2.1 Early observations and theories ...... 170 7.2.2 The Big Bang: from hypothesis to theory ...... 171 7.2.3 The inflationary universe ...... 173 7.3 Origin of Matter and Forces of Nature ...... 174 7.4 Formation of the Solar System ...... 176 7.5 The Hadean: Origin of Earth and Moon ...... 179 7.5.1 Earth’s earliest evolution ...... 179 7.5.2 Origin of the Moon ...... 182 7.6 The Archean: Beginnings of a Permanent Crust ...... 185 7.6.1 Shields and cratons: cores of continents ...... 185 7.6.2 Gneiss terranes ...... 185 7.6.3 Greenstone belts ...... 186 7.6.4 Microplate tectonics and dierentiation of the early crust ...... 188

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9781284457162_FMxx_00i_xxii.indd 7 07/11/16 1:46 pm 7.7 Climatic Evolution of the Inner Planets ...... 190 7.7.1 Habitable zone ...... 190 7.7.2 Faint young sun ...... 192 7.7.3 Weathering and tectonism on the inner planets ...... 193

CHAPTER 8 Origins of Life ...... 200 8.1 Life as a Geologic Force ...... 201 8.2 Early Theories of the Origin of Life: Spontaneous Generation and Panspermia ...... 201 8.3 What Is Life? ...... 202 8.3.1 Basic traits of life ...... 202 8.3.2 Composition of life ...... 203 8.4 Chemical Evolution ...... 203 8.4.1 Early theories ...... 203 8.4.2 Hydrothermal vents and the pyrite world ...... 208 8.4.3 The RNA world ...... 209 8.4.4 Autocatalysis ...... 211 8.5 Origin of Eukaryotic Cells ...... 213 8.6 Precambrian Fossil Record and Molecular Clocks ...... 215 8.7 Is There Life on Other Planets? ...... 218 CHAPTER 9 The Proterozoic: Life Becomes a Geologic Force ...... 225 9.1 Significance of the Proterozoic ...... 226 9.2 Appearance of Modern Plate Tectonics...... 226 9.3 Sedimentary Rocks and Continental Shelves ...... 230 9.4 Oxygenation of Earth’s Atmosphere ...... 232 9.4.1 Appearance of oxygen ...... 232 9.4.2 Stages in the oxygenation of Earth’s atmosphere ...... 235 9.4.3 Rise of ozone ...... 237 9.5 Snowball Earth: Earth Out of Balance? ...... 237 9.5.1 Previous hypotheses for Snowball Earths ...... 237 9.5.2 Snowball Earth reexamined ...... 240 9.5.3 How could a Snowball Earth have occurred in the first place? ... 242 9.5.4 Why were there no Snowball Venuses? ...... 243 9.5.5 Why didn’t Snowball Earths recur aer the Precambrian? ...... 245 CHAPTER 10 Life’s “Big Bang”: The Origins and Early Diversification of Multicellular Animals ...... 249 10.1 Enigma of Multicellular Organisms ...... 250 10.2 Stages of Life’s Big Bang ...... 250 10.2.1 Ediacara fauna ...... 251 10.2.2 Trace fossils and early hard parts ...... 253 10.2.3 Burgess Shale and the “Cambrian explosion” ...... 259 10.3 What Do These Faunas Tell Us? ...... 263

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9781284457162_FMxx_00i_xxii.indd 8 07/11/16 1:46 pm 10.4 Why Did Metazoans Appear? ...... 266 10.4.1 Snowball Earths ...... 266 10.4.2 Oxygen ...... 267 10.4.3 Predation ...... 267 10.4.4 Food ...... 268 10.4.5 Changes in biogeochemical cycles ...... 269 10.4.6 Ecologic and genetic mechanisms ...... 269 10.4.7 Extinction ...... 270 10.5 Molecular Clocks and the Fossil Record of Early Metazoans ...... 271

PART III The Phanerozoic: Toward the Modern World ...... 275 CHAPTER 11 The Early-to-Middle Paleozoic World ...... 277 11.1 Introduction: Beginnings of the Phanerozoic Eon ...... 278 11.2 Tectonic Cycle: Impacts on the Hydrosphere, Atmosphere, and Rock Cycle ...... 278

11.2.1 Sea level, CO2, and sedimentary facies ...... 278 11.2.2 Ocean circulation and chemistry ...... 286 11.3 Tectonic Cycle and Orogeny ...... 287 11.3.1 Physiographic provinces of the Appalachian Mountains ...... 287 11.3.2 Orogenic episodes ...... 290 11.4 Impact of Orogeny on Earth Systems ...... 296 11.5 Diversification of the Marine Biosphere ...... 299 11.5.1 Plankton and microfossils ...... 299 11.5.2 Benthic ecosystems ...... 300 11.5.3 Reefs ...... 305 11.6 Marine Realm Invades the Terrestrial Biosphere ...... 308 11.6.1 Invertebrates ...... 308 11.6.2 Fish ...... 308 11.6.3 Amphibians and the invasion of land ...... 317 11.6.4 Land plants and the “greening” of the continents...... 318 11.7 Extinction ...... 322 CHAPTER 12 Late Paleozoic World ...... 328 12.1 Introduction to the Late Paleozoic Era ...... 329 12.2 Tectonic Cycle: Impacts on the Hydrosphere, Atmosphere, and Rock Cycle ...... 330

12.2.1 Sea level, CO2, and sedimentary facies ...... 330 12.2.2 Ocean circulation and chemistry ...... 330 12.3 Tectonic Cycle and Orogeny ...... 332 12.3.1 Alleghenian and related orogenies ...... 332 12.3.2 Ancestral Rockies ...... 333 12.3.3 Sonoma orogeny ...... 334 12.4 Impact of Orogeny on Earth Systems ...... 336

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9781284457162_FMxx_00i_xxii.indd 9 07/11/16 1:46 pm 12.5 Diversification of the Marine Biosphere ...... 338 12.5.1 Plankton and other microfossils ...... 338 12.5.2 Benthic ecosystems ...... 340 12.6 Diversification of the Terrestrial Biosphere ...... 343 12.6.1 Terrestrial floras ...... 343 12.6.2 Terrestrial floras and oxygen ...... 346 12.6.3 Invertebrate life on land ...... 348 12.6.4 Vertebrates ...... 348 12.7 Multiple Causes of Extinction? ...... 354 CHAPTER 13 Mesozoic Era ...... 364 13.1 Introduction to the Mesozoic Era ...... 365 13.2 Tectonic Cycle: Impacts on the Hydrosphere, Atmosphere, and Rock Cycle ...... 365 13.2.1 Riing of Pangaea ...... 365

13.2.2 Sea level, CO2, and sedimentary facies ...... 366 13.2.3 Ocean circulation and chemistry ...... 368 13.3 Tectonic Cycle and Orogeny ...... 371 13.3.1 Eastern North America ...... 371 13.3.2 Cordilleran Orogenic Belt ...... 372 13.3.3 Orogenic episodes ...... 372 13.4 Orogeny, Sea Level, and Sedimentation ...... 377 13.5 Diversification of the Marine Biosphere ...... 381 13.5.1 Plankton and microfossils ...... 381 13.5.2 Benthic ecosystems ...... 382 13.5.3 Marine vertebrates ...... 387 13.6 Diversification of the Terrestrial Biosphere ...... 390 13.6.1 Plants and insects ...... 390 13.6.2 Vertebrates ...... 393 13.6.3 Evolution of flight ...... 406 13.6.4 Mammals ...... 409 13.7 Extinction ...... 411 13.7.1 Late Triassic extinctions ...... 411 13.7.2 Late Cretaceous extinctions ...... 411 CHAPTER 14 The Cenozoic Era: The Paleogene Period ...... 421 14.1 Introduction to the Cenozoic Era ...... 422 14.2 Tectonic Cycle and Orogeny ...... 423 14.2.1 Europe and Asia ...... 423 14.2.2 The Pacific Rim ...... 423 14.2.3 Gulf and Atlantic coastal plains ...... 429 14.3 Tectonic Cycle: Impacts on Climate, Ocean Circulation, and Chemistry ...... 429 14.3.1 Climate and ocean circulation ...... 429 14.3.2 Ocean chemistry ...... 434 x Contents

9781284457162_FMxx_00i_xxii.indd 10 07/11/16 1:46 pm 14.4 Diversification of the Marine Biosphere ...... 435 14.4.1 Microfossils and other invertebrates ...... 435 14.4.2 Vertebrates ...... 435 14.5 Diversification of the Terrestrial Biosphere ...... 437 14.5.1 Plants ...... 437 14.5.2 Early evolution and diversification of mammals ...... 438 14.5.3 Archaic mammals ...... 440 14.5.4 Climate change and mammals ...... 441 14.5.5 Diversification of modern mammals ...... 445 14.5.6 Birds ...... 446 14.6 Extinction: Glaciers, Volcanoes, and Impacts ...... 448 CHAPTER 15 The Cenozoic Era: The Neogene Period ...... 456 15.1 Introduction to the Neogene...... 457 15.2 Tectonics and Sedimentation ...... 458 15.2.1 Europe, Asia, and Africa ...... 458 15.2.2 Central and South America ...... 458 15.2.3 Atlantic and Gulf Coasts of North America ...... 458 15.2.4 Western North America ...... 458 15.2.5 West Coast of North America ...... 462 15.2.6 Evolution of the San Andreas Fault system ...... 465 15.3 How Was the West Widened? Evolution of the Basin and Range ...... 466 15.3.1 Background ...... 467 15.3.2 Hypotheses for the formation of the Basin and Range ...... 467 15.4 Climate, Ocean Circulation, and Chemistry ...... 470 15.5 The “Ice Ages”: Evolution of a Theory ...... 472 15.5.1 Background ...... 472 15.5.2 The eccentricity of James Croll ...... 472 15.5.3 Precession of the equinoxes ...... 472 15.5.4 Milutin Milankovitch and obliquity ...... 475 15.5.5 Planktonic foraminifera and the oxygen isotope curve ...... 477 15.6 Neogene Life ...... 479 15.6.1 Marine life ...... 479 15.6.2 Land plants ...... 480 15.6.3 Terrestrial vertebrates ...... 481 15.6.4 Evolution of humans ...... 481 15.7 Extinction ...... 492 PART IV Humans and the Environment ...... 499 CHAPTER 16 Rapid Climate Change During the Holocene ...... 501 16.1 Introduction to the Holocene ...... 502 16.2 Beginning of the Holocene ...... 502 16.2.1 Sea-level rise ...... 502 16.2.2 Younger Dryas ...... 503 Contents xi

9781284457162_FMxx_00i_xxii.indd 11 07/11/16 1:46 pm 16.3 Rapid Climate Change on Millennial Time Scales ...... 507 16.3.1 Rapid climate change involving the oceans ...... 511 16.3.2 Rapid climate change on land ...... 512 16.4 Rapid Climate Change on Centennial Time Scales ...... 513 16.5 Rapid Climate Change on Interdecadal to Multidecadal Time Scales ... 514 16.6 Climatic Modes and Climatic Irreversibility ...... 518 CHAPTER 17 The Anthropocene: Humans as an Environmental Force ...... 524 17.1 Introduction: From Geohistory to Geopolitics ...... 525 17.1.1 Climate, history, and the modern world ...... 525 17.2 Examples of Human–Climate Interactions During the Last Millennium ...... 526 17.3 Brief History of the Growing Dependence on Fossil Fuels ...... 527 17.4 Alternative Energy Sources and Technologies ...... 529 17.4.1 Wind, geothermal, and solar energy ...... 530 17.4.2 Hydroelectric power ...... 530 17.4.3 Nuclear energy ...... 535 17.4.4 Methane gas hydrates ...... 537 17.4.5 Biofuels ...... 537 17.4.6 Automobiles ...... 537 17.5 Consequences of Fossil Fuel Combustion ...... 538 17.5.1 Carbon dioxide: Temperature rise and ocean acidification ..... 538 17.5.2 Sea-level rise ...... 542 17.5.3 Storms ...... 542 17.5.4 Fisheries ...... 543 17.5.5 Precipitation patterns ...... 543 17.5.6 Disease ...... 546 17.6 Biodiversity and Extinction ...... 548 17.7 Closer to Home ...... 552 17.8 Why Should We Care, and What Can We Do? ...... 557 Glossary...... 563 Index ...... 593

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9781284457162_FMxx_00i_xxii.indd 12 07/11/16 1:46 pm PREFACE TO TH E SECOND EDITION: FOR THE INSTRUCTOR AND STUDENT

As the title indicates, Earth’s Evolving Systems attempts to Part I: Earth Systems: Their Nature bridge the gap between traditional historical geology texts and the study of Earth’s systems. The response to the first and Their Study edition of Earth’s Evolving Systems has been quite gratifying, Major changes were made to Chapters 1–6 to improve the especially given the recent emphasis by a National Science flow of the material in Part I: Foundation–sponsored webinar by the American Geophys- ical Union and American Geological Institute in October nn Chapter 1: A brief discussion of Vladimir Vernadsky, the 2015 entitled “Geoscience Workforce and the Future of founder of Earth systems science, has been added. The Undergraduate Geoscience Education.” The respondents to discussion on the nature of historical sciences such as this webinar emphasized at the outset the complex, dynamic geology has been improved by eliminating Chapter 18 linkages among Earth’s systems, the role of “deep time” (and from the rst edition and incorporating certain elements thus the role of the scale of time in understanding process), of that chapter into Chapter 1. the origin and evolution of life, climate change, and energy nn Chapter 2: As before, much of the discussion of Earth’s resources. All of these topics were emphasized in the first history revolves around the framework of the tectonic edition of Earth’s Evolving Systems and continue to be empha- cycle. Plate tectonics has therefore been moved from sized in the second. Chapter 6 to Chapter 2. Nevertheless, there is always room for improvement, nn Chapter 3: The discussion of the interactions among and I have attempted to respond positively to reviewers’ Earth’s systems has been simplied, and the introduc- comments on the first edition. This has of course involved tion and discussion of specic stable isotopes have been some compromises, given each instructor’s approach to his pushed back to the chapters where they are explicitly tied or her particular course and research and teaching interests. to the geologic record. A new section has been added to Chapters have been updated with information on significant this chapter, “How Does the Tectonic Cycle Affect Other advances that have been reported in the literature over the Earth Systems?” which describes the effects of the tec- past several years. Themes stated at the beginning of each tonic cycle on sea level, ocean circulation, the hydrologic chapter are now restated or rephrased, in some cases as “big cycle, and major lithologies. concept” questions, which are highlighted at relevant points nn Chapters 5 and 6: Chapter 5, which presents evolu- in the text margins of the chapters. As before, each chapter tion, remains largely unchanged, but it now precedes is followed by a summary that provides a detailed overview Chapter 6, which deals with geologic time and stratig- of the chapter. raphy. Discussion of iterative evolution has been moved The following key points about the second edition are from Chapter 14 to the section on marine organisms dur- applicable to all chapters: ing the Paleogene. nn As in the rst edition, a major theme of the text is the method of multiple working hypotheses and debates, Part II: The Precambrian: Origin and among them the origin of the theory of plate tectonics, Early Evolution of Earth’s Systems the origins of the atmosphere and life, the tectonics of the western United States, human evolution, and the recog- nn Chapter 7: Chapter content has been updated to reect nition of Milankovitch cycles. the most recent research. nn Discussion and contributions and photos of some major nn Chapter 8: A few reviewers questioned the relevance of women scientists to the earth sciences, such as Marie a chapter on the origins of life in an Earth science text. Tharp and Lynn Margulis, have been included in the rel- However, I believe that life’s origins are among the most evant chapters. fascinating chapters in Earth’s history and that this is nn An extensive list of references is provided at the end of when the initial, fundamental interactions among all of each chapter, along with a list of key terms and review Earth’s systems began to occur. Life has been a geologic questions. In addition, a second set of questions, called force throughout much of Earth’s history, as empha- “Food for Thought,” is provided to stimulate students to sized throughout the text. The study of the interac- think beyond the chapter material. tions between life and Earth therefore serves as a bridge

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9781284457162_FMxx_00i_xxii.indd 13 07/11/16 1:46 pm between the biologic and inorganic worlds. Furthermore, Part IV: Humans and the Environment like evolutionary theory, origin of life studies present via- ble alternatives to Creationism. A new paragraph at the nn Chapter 16: As before, Chapter 16, which is on rapid beginning of the chapter now reiterates the rationale for climate change, sets the stage for the Gordian knot of retaining Chapter 8. natural versus anthropogenic climate change and its nn Chapter 9: Chapter content has been updated to reect sociopolitical implications for future climate and energy the most recent research. resources, which are discussed in Chapter 17. nn Chapter 10: The discussion of the origins of various nn Chapter 17: As explained in Chapter 1, the initial study important fossil phyla has been augmented. of Earth systems was a response to anthropogenic effects. Humans are now a major, if not the most important, geologic force on the planet. The emphasis on the environ- Part III: The Phanerozoic: Toward the ment and “sustainability” at many academic institutions, Modern World including my own, does not diminish the importance of historical sciences, such as geology, in addressing these nn Chapters 11–15: Chapters on the Phanerozoic con- problems. In fact, the inclusion of chapters on anthro- tinue to use the tectonic cycle as a basic framework for pogenic impacts and their potential resolution is a prime understanding the history of the Earth. Many gures opportunity to make historical geology not just an exer- in these chapters have been replaced and sections on cise in the “past” but to make it “contemporary” and “rel- various taxa augmented with multiple photos and new evant” and to potentially awaken students’ latent interest artwork. in the history of Earth and its lifeforms. Consequently, nn Chapter 15: The section on human evolution in Chapter I have occasionally tied certain portions of Chapters 16 15 has been completely revised and reviewed by two pro- and 17 to examples from the geologic record. fessional paleoanthropologists. CHAPTER Ron Martin Newark, Delaware 1 August 10, 2016

Introduction: Investigating Earth’s S y s t e m s

E Why is geologic time important to understanding how Major Concepts and Questions AddressedEarth’s systems ininteract? This Chapter F How do di erent processes act on di erent durations of time? A Why study the history of Earth? G How do we study Earth’s systems and the history of B How did the science of Earth systems arise? t h e i r i n t e r a c t i o n s ? C What is a system, and how does it work? D What are Earth’s systems, and what are their basic characteristics?

1.4 Directionality and the Evolution of Earth Chapter Outline S y s t e m s 1 . 5 G e o l o g y a s a n H i s t o r i c a l S c i e n c e 1 . 1 W h y S t u d y t h e H i s t o r y o f E a r t h ? 1 . 6 M e t h o d a n d S t u d y o f E a r t h ’ s E v o l v i n g S y s t e m s 1.2 What Are the Major Earth Systems, and What A r e T h e ir C h a r a c t e r is t ic s ? The Origins of the Science of Earth Systems B O X 1 . 1 1 . 3 G e o l o g i c T i m e a n d P r o c e s s

compassed an

The Anasazi cli dwellings at Mesa Verde National Park, Colorado. The Anasazi (the “Ancient Ones”) civilization vanished suddenly, possibly as a result of prolonged drought. The Anasazi civilization once en area the size of New England in the Four Corners region where Colorado, Utah, New Mexico, and Arizona meet today. Based on archeological evidence, the Anasazi civilization ourished during what is called the Little Climate Optimum from about 900–1300, and traded with other civilizations as far south as Mexico and Central America. The Anasazi adopted an agricultural lifestyle and built extensive cities in the sides of cli s. However, 3 the Anasazi began to disperse from about 1280–1300, leaving behind their dwellings, and their civilization disappeared. Similarly, increasing evidence indicates that modern global change—due to the combustion of fossil fuels—will alter precipitation patterns, leading to more intense heat waves and prolonged drought in di erent regions all over the world, including North America. Courtesy of National Park Service.

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xiv Preface to the Second Edition: For the Instructor and Student

9781284457162_FMxx_00i_xxii.indd 14 07/11/16 1:46 pm THE STUDENT EXPERIENCE

The second edition of Earth’s Evolving Systems: The History nn Major Concepts and Questions Addressed in This of Planet Earth was designed with numerous features to cre- Chapter—Every chapter opens with a list of questions ate an engaging learning environment for students and to that will be addressed throughout the chapter. Students enhance their experience with the text: should review this list prior to digging into the chapter to help guide their focus. The new text design also incorpo- rates icons identifying where in the chapter each concept is addressed to help guide study and review.

CHAPTER 1

1.1 Why Study the History of Earth? Introduction: the present (refer to this chapter’s frontispiece). Humans Earth’s Evolving Systems is about the history of the A have now begun to affect Earth’s environments at rates much Investigating Earth’s Earth, the natural processes that have shaped it, and the history of these processes and their interactions through faster than the rates of natural processes. The rapid growth S y s t e m s vast intervals of time. of human populations ( history of the Earth and its life preserved as fossils. agriculture and deforestation, heavy industry and power Why is geologic time important to understanding how Geology is the science that studies the Figure 1.1) has led to the spread of E plants fired by fossil fuels, and the dependence on petro- Major Concepts and Questions AddressedEarth’s systems ininteract? This Chapter Why should we be concerned about Earth’s history? F How do di erent processes act on di erent durations Because understanding how the Earth changes and has leum (oil and gas) to power automobiles for transportation of time? changed tells us about how natural processes affect humans (Figure 1.2). A Why study the history of Earth? G How do we study Earth’s systems and the history of B How did the science of Earth systems arise? t h e i r i n t e r a c t i o n s ? and how humans affect natural processes. The history of the The burning of fossil fuels releases C What is a system, and how does it work? Earth confronts us with events and possibilities that we can- especially carbon dioxide, into the atmosphere. Greenhouse What are Earth’s systems, and what are their basic D not imagine. Many natural processes act so slowly we would gas traps solar radiation as heat in Earth’s greenhouseatmosphere, gasescaus- characteristics? ing the atmosphere and surface to warm ( be unaware of them except for the geologic record of their , activities preserved by rocks and fossils. Most people are out carbon dioxide in the atmosphere, Earth’s average surface temperature would be about –18°C (0.5°F) instead of its cur- unaware that Earth’s environments are constantly changing. Figure 1.3 1.4 Directionality and the Evolution of Earth We assume that landscapes—mountains, valleys, rivers and rent (and more comfortable!) temperature of +15°C (59°F).). With- Chapter Outline S y s t e m s But humans have begun to burn fossil fuels at an unprece- 1 . 5 G e o l o g y a s a n H i s t o r i c a l S c i e n c e streams, and coasts—do not change because the changes are typically so slow and subtle they take place over time spans dented rate, and no one really knows what the outcome 1 . 1 W h y S t u d y t h e H i s t o r y o f E a r t h ? 1 . 6 M e t h o d a n d S t u d y o f E a r t h ’ s E v o l v i n g S y s t e m s will be of the rapid accumulation of carbon dioxide in the 1.2 What Are the Major Earth Systems, and What equivalent to many, many human generations; from many A r e T h e ir C h a r a c t e r is t ic s ? millions of years down to millennia and centuries. Also, some atmosphere. In fact, carbon dioxide levels in the atmosphere The Origins of the Science of Earth Systems B O X 1 . 1 processes are so infrequent or sudden, we would not know have increased about 30% since the beginning of the Indus- 1 . 3 G e o l o g i c T i m e a n d P r o c e s s they occur except, again, to look at the geologic record. trial Revolution ( concentrations in gas bubbles found in core samples taken Scientists have only recently begun to appreciate just Figure 1.4 B through the glacial ice of Greenland). We know and this Antarctica. based on carbon The bub- how strongly changes in Earth’s environments have ce encompassed an affected—and still affect—humankind, from our evolution- bles are a record of the composition of ancient atmospheres. ary beginnings through the origins of ancient settlements As the use of fossil fuels has increased, so too has Earth’s aver- and civilizations—and perhaps their collapse—right up to age surface temperature, so that the greenhouse effect is no longer considered by most scientists to be purely natural. As far as scientists can tell, these changes will continue through The Anasazi cli dwellings at Mesa Verde National Park, Colorado. The Anasazi (the “Ancient Ones”) civilization vanished suddenly, possibly as a result of prolonged drought. The Anasazi civilization on 8 the 21st century and beyond, potentially affecting future area the size of New England in the Four Corners region where Colorado, Utah, New Mexico, and Arizona meet today. Based on archeological evidence, the Anasazi civilization ourished during what is called the Little Climate Optimum from about 900–1300, and traded with other civilizations as far south as Mexico and Central America. The Anasazi adopted an agricultural lifestyle and built extensive cities in the sides of cli s. However, 3 human generations, environments, and ecosystems. the Anasazi began to disperse from about 1280–1300, leaving behind their dwellings, and their civilization disappeared. Similarly, increasing evidence indicates that modern global change—due to the combustion of fossil fuels—will alter precipitation patterns, leading to more intense heat waves and prolonged drought in di erent regions all over the world, including North America. 7 Courtesy of National Park Service.

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Population (billions)3 Green Revolution World War II 2 xv Advances in medicine/sanitation Railroads and steamships

1 Neolithic agricultural revolution Industrial Revolution © Jones & Bartlett Learning, LLC, an Ascend Learning Company. NOT FOR SALE OR DISTRIBUTION Emigration to New World begins Rome falls Rise of Black Death—the plague Islam 0 Crusades begin 9781284457162_FMxx_00i_xxii.indd 15 07/11/16 1:46 pm 8000 B.C. 1 A.D.

500 FIGURE 1.1 beginning in theHuman 1800s population in response growth. to the IndustrialGlobal human Revolution population and advances growth since in medicine1000 8,000 B.C. and Note sanitation. the steep rise of population growth Year 1500 4 Chapter 1 Data from: United States Census Bureau, International Programs Center, 2001.2016 Introduction: Investigating Earth’s Systems

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26/10/16 11:02 am every 100,000 years; (2) obliquity (“tilt”) of Earth’s axis toward or away from the sun, which affects the amount of solar radiation impinging on the northern hemisphere and which completes one cycle every and erosion all over the world. Also, the calcite com- 40,000 years; and (3) precession of the equinoxes pensation depth tended to deepen as sea level fell. about every 19,000 to 23,000 years, which affects the nnA permanent polar ice cap began to grow on Ant- occurrence of the seasons within Earth’s orbit around arctica as it continued to move over the South Pole, the sun. which led to a lowering of sea level. nnThe growth of ice sheets in the northern hemisphere nnIce caps also appeared in the northern hemisphere, might have caused forests to further shrink and grass- based on ice-rafted debris about 2.8 million years old in tens-of-millions of years before the end of the Cretaceous lands to expand. With the continued expansion of period (see Further Reading). In any case, the demise of the deep-sea cores taken off the British Isles. This followed grasses came further diversication of artiodactyls. dinosaurs gave the mammals the opportunity to diversify in about 700,000 years after the rise of the Isthmus of Similarly, according to the turnover pulse hypothesis, the Cenozoic (see Chapter 14). There is now a general con- Panama, which is thought to have blocked the ow of shrinking forests caused ancient human ancestors, sensus that one or more meteors hit Earth at the end of the many taxa on land and in the sea could not tolerate. Indeed, warm-water currents from the Atlantic into the Pacic. the Late Cretaceous extinctions are associated with one or or hominids, which were arboreal, to leave forests Cretaceous, and that impact was the primary cause of the The diversion of warm waters northward into the Gulf final demise of the dinosaurs and other taxa on land and in more iridium layers that presumably settled out with the dust for grasslands. On the other hand, human evolution the sea. The sudden injection of dust high into Earth’s atmo- after the impact(s). More important, well-developed shocked of Mexico and the western Atlantic Ocean transported might have resulted from changes in behavior. sphere is thought to have caused rapid global cooling, which mineral assemblages and microtektites occur at the end of warm, moist air to higher latitudes, where it began to nnIn either case, our ancestors eventually began to walk the Cretaceous Period. The intensity of metamorphism of precipitate as snow and ice. With the appearance of upright. As hominids evolved, different populations the shocked minerals could only have occurred by a sud- ice caps in the northern hemisphere, production of den increase in intense pressures and temperatures like those might have coexisted in the same habitats and might generated during an impact (see Chapter 3 and North Atlantic Deep Water began, which, along with have migrated a number of times to Asia and even- the production of Antarctic Bottom Water, resulted in tually to Europe. As humans spread across the globe nn Featured Boxes—Many chapters contain boxes increasing oxygenation of the deep oceans. during the Holocene, they might have contributed to B O X 1 3 . 3 Box 13.3 providing greater depth on special topics. Late Cretaceous Extinctions and the Scientific Method ). nnAfter the northern hemisphere ice sheets were estab- the demise of different species of large mammals and lished, they waxed and waned in response to the ightless birds. M o s t m a s s e x t ni c t oi n s a p p e a r t o b e s o m e h o w r e la t e d amount of solar radiation reaching Earth’s surface. to the tectonic cycle. However, the Late Cretaceous extinctions involved—and may well have resulted Cycles of solar radiation are thought to represent primarily from—an impact, as indicated by the Milankovitch cycles of solar radiation that occur at nI ti ai ly , a d a r k s e d mi e n t a r y la y e r c o n t a ni ni g a three dominant periods: (1) eccentricity (or “elliptic- occurrence of shocked mineral assemblages high concentration of the element iridium was found (Box Figure 13.3A ) . W h e r e a s t h e mi p a c t h y p o t h e s si near Gubbio, Italy, almost by accident (see Chapter 1). ity”) of Earth’s orbit that completes one cycle about certainly arouses our imaginations, how the The iridium layer also occurred at the time of the hypothesis came to be widely accepted by the mass extinction at the end of the Cretaceous Period scientific community is also a prime example of about 65 million years ago, during which dinosaurs how scientific investigation works (see Chapter 1). and many other organisms became extinct. Iridium is species Moreover, the corroboration of the hypothesis not normally found in rocks of Earth’s crust and could stereoscopic vision paved the way for the acceptance of extraterrestrial have come from only two sources: volcanoes fed by overkill hypothesis impacts as important—even extraordinary—agents strepsirrhines the mantle, which is enriched in iridium, or from an oxygen isotopes of geologic, climatic, and biospheric change. It also extraterrestrial body. The hypothesis was that the Key Terms Gulf Stream summer solstice radically altered—once and for all—earth scientists Pacific plate iridium layer was generated by a meteor enriched haplorhines supraorbital ridge BOX 13.3 Late Cretaceous Extinctions and the Scientific Method (Continued) unquestioned acceptance of Lyell’s dogma of slow, in iridium. The impact presumably threw a gigantic aquifer precess Holocene terminations gradual change to a broader doctrine that recognized dust cloud into Earth’s stratosphere that suddenly precession of the equinoxes Basin and Range Province tilt that Earth systems processes vary through time and in cooled the planet, causing extinction; the blockage horst-and-graben along with irons and stony-irons, are thought to have origi- C3 grasses Primates r a t e (s e e C h a p t e r 1 ). of sunlight also shut down marine photosynthesis Juan de Fuca plate turnover pulse nated by the melting and recrystallization of primitive plan- Rio Grande Ri causing a C4 grasses ungulates Strangelove Ocean ( n a m e d a e r t h e Lake Bonneville etary material. Iron meteorites appear to represent portions character of the same name in a famous movie) in Coast Ranges San Andreas Fault mammoths winter solstice which there was a sudden, strong shi in carbon Cocos plate Sierra Nevada of asteroid cores. isotope ratios to much lower values (see Chapter 9; Milankovitch cycles wobble Also thought to be left over from the origin of the solar diluvial theory single origin chemical differences exist between different meteorites that Box Figure 13.3B ) . moraines comets (Figure 7.14). Comets are basically “dirty East Pacific Rise single species hypothesis cannot be explained if the meteorites came from only a few system are kometeos, A p r e d ci t oi n m a d e fr o m t h e h y p o t h e s si w a s t h a t multiregional evolution if an impact were responsible for the Late Cretaceous Sixth Extinction large planets. Based on chemical analyses most meteorites eccentricity hypothesis snowballs.” They consist of a nucleus of ice (either water or extinctions, an iridium layer should be found all over slab gap hypothesis nn Concept and Reasoning Checks—As Farallon plate obliquity appear to have come from the asteroid belt between Mars frozen carbon dioxide) and soot surrounded by a gaseous the world in rocks of exactly the same age. Scientists Courtesy of Ron Martin. tested the hypothesis by exploring for the iridium layer Front Range Out of Africa hypothesis and Jupiter. envelope and a long,students trailing progresstail (hence thethrough name the chapter they all over the world, on land and in deep-sea cores, glacial erratics Meteorites are themselves of several types, depending where the rocks were of the right age. The hypothesis meaning “long-haired”). Although a comet’s nucleus might Great American Interchange chondrites and will encounter these questions, which will was corroborated: the Late Cretaceous iridium layer on the relative amounts of silicate minerals and iron: stony, be only 1 to 10 km Ain possible size, the tsunami tail can deposit reach generated tens of mil- is now known not only from Gubbio, Italy, but also encourage them to pause and assess their How might have tectonism contributed to the growth from Stevns Klint (Steven’s Cli ) near Copenhagen, 5. stony-irons, and irons (Figure 7.13). Stony meteorites are lions of kilometers in length. The tail points away from the of glaciers over both poles of Earth? BOX FIGURE 13.3E BOX FIGURE 13.3A Denmark; El Kef, Tunisia, in north Africa; and El the most abundant and are of two types: grasp of the material. What is the evidence for the advance and retreat of bysun the and Late consists Cretaceous of ionized impact in atoms the Yucatan and dust (Mexico). blown This off by a n a s te ro di w tih E a rt h . An artist’s visualization of © the Gl0ck/ShutterStock, impact Inc. of Mimbral, Mexico (to name only a few of the more Review Questions 6. achondrites. Carbonaceous chondrites contain carbon, solar wind, the immense stream of ionized particles famous and intensively studied localities), as well as in northern hemisphere glaciers from land? From the ordinary chondrites do not (the Murchison mete- sitethe is located along the north coast of Cuba. An alternative How do Paleogene and Neogene events differ from plasma produced by the fusion of hydrogen atoms into many deep-sea cores (see Box Figure 13.3B ) . 1. deep sea? whereas eor x p la n a t io n is t h a t t h is s e c t io n r e p r e s e n t s a s u b m a r in e s lu m p . each other? Make a chart labeled Paleogene and Neo- How do the three major Milankovitch frequencies Courtesy of Virgil L. Sharpton, Lunar Planetary Institute. 7. 24/10/16 11:49 am orite that was dated to determine the age of Earth was an helium. The solar wind and ultraviolet radiation observed 412 gene across, and down the left, (d)side ocean of the circulation, chart list interact to produce climate change? Do all three fre- Chapter 13 provinces, 2 Oort cloud, which Mesozoic Era the following: (a) continental movements, (b) sea iron meteorite). Possibly, while the Earth was coalescing, emanating At the time from of the youngimpact the stars Yucatan is region quite was intense, and our sun The Cenozoic Era: Thequencies Neogene always Period accentuate glaciation or warming? M a g n e t ic a n o m a ly m a p o f c r a t e r . the poles can be as low as 0°C, so that different species tend level, (c) atmospheric CO Why or why not? (continues) Chapter 15 ordinary chondrites were heated above about 450 K, vapor- must have been no different. 9781284457162_CH13_PASS02.indd 412 (e) oxygen, (f) plankton,496 (g) calcite compensation BOX FIGURE 13.3D a shallow seaway. Thus, the impact is thought to to characterize each water mass. The oceanic realm is in 8. How does the evolution of humans resemble that of izing carbon and water, whereas carbonaceous chondrites Comets appear to originate in the turn characterized by one or more smaller scale depth, (h) terrestrial plants, and (i) terrestrial animals. other taxa, such as the horse? What factors contrib- have generated one or more tsunamis, perhaps up nn Summaries—Each chapter concludes with 2. On a map of North America or another continent(s) of uted to the evolution of humans? were originally located farther from the sun. is located far beyond the edge of the solar system at a dis- especially where different ocean currents encroach on land the world, nd the following features that formed dur- Carbonaceous chondrites might have been an impor- to 1 kilometer high, that roared across Mexico, the 9. Evaluate the different hypotheses for human evo- intensely red, eventually becomingdeuterium incandescent (which has like an tance up to 1,000 times the diameter of Pluto’s orbit around masses. Thus, in the marinea realmbulleted species list living of the closer key to concepts addressed ing the Neogene and discuss how they formed: Ama- lution for their strengths and weaknesses: multire- Caribbean, CONCEPT and into AND the REASONING interior of NorthCHECKS America, zon rain9781284457162_CH15_PASS02.indd forest, Amazon River, Arabian 496 Peninsula, Aral tant sourcea light bulb, of water as forests on Earth. werehydrogen This immolated inference (D/H ratio) and is based impact in water. on the sun. When dislodged by gravitational forces of the outer land occur in provinces whosein the boundaries chapter. correspond to gional, single species, and turnover pulse. ripping up the sea bottom and redepositing layers of Sea, Basin and Range, Cascade Mountain Range, Coast What is the difference between a species and a race? the ratioejecta of therained hydrogen down. isotope planets or distant stars, comets move into the inner solar changes in temperature and salinity between adjacent water 24/10/16 11:42 am Ranges, East African Rift Valley, Front Range, Greater 10. poorly Dsorted i a g r a m t h esedimentary h y d r o l o g i c c y c l e . debris ranging from mud to 11. What was happening on Earth about 10,000 to extra neutron) The impact to normal is estimated to have released an system.1. Then, they assume highly elliptical orbits around masses impinging on the coasts. Antilles, Gulf of California, Himalayas, Isthmus of Pan- 11,000 years ago? How are the hydrologic cycle and atmospheric circulation ama, Mississippi River, Rio Grande Rift, San Andreas The D/Hamount ratio of for energy Earth equivalent falls within to the 100 range million of megatons carbon- largethe2. sun blocks. at angles Jumbled, to the poorly plane sortedof the ecliptic.deposits Because of rocks they These distinctive biotas have also changed through time r e l a t e d ? Fault, Sierra Nevadas, and Yellowstone hotspot. aceous chondrites. Because deuterium was evaporated is heavier into than space. nor- By andcontain sediments—like so much water, those comets that wouldhave been have suggested been to have as continents have changed position during tectonic cycles. What was the effect of the uplift of the Himalayas on of , TNT it would (1 megaton have remained equals2 behind 1 million in the tons), water or vapor one What drives surface ocean circulation?Box Figure 13.3E ) . 3. mal H 2 depositedplayed3. a major by a tsunami—haverole in the formation in fact of been Earth’s found oceans; from how- In the process, populations of many different kinds of plants global climate? (See also Chapter 2.) billion times the energy of the first atomic bombs and 4. What causes the deep oceans to circulate? of meteorites as the lighter H thisever, time their in deuterium-to-hydrogenvarious places ( (D/H) ratios are about and animals have become separated from one another for tens 4. What was the effect of the rise of the Isthmus of Panama about 10,000 times that of the entire world’s nuclear 5. How do the oceans influence Earth’s albedo?T. rex and the crater of doom . on global climate and life on land and in the oceans? contrast, achondrites exhibit a wide range of textures and, twice those of Earth’s. to hundreds of millions of years, evolving their own distinc- arsenal at the peak of the Cold War. The fireball of tive faunas and floras, for example, the distinctiveof it; (3) marsupial gravity slide, in which a slab slowly “slides” the impact was so great it blew a hole through the down the side of a spreading center, pushing the slab 3.5 The Biosphere faunaSummary of Australia. Rifting of a continent can, forahead example, of it; and (4) suction from the descending por- atmosphere into outer space! CONCEPT AND REASONING CHECKS lead to the evolution of what was once a singletion biota of a plate. into two nnThe theory of plate tectonics really began with nnBased on plate tectonics, different features of the planet early ideas about orogenesis, or mountain build- 3. Describe the tectonics and sedimentation of the west- or more regions separated by new ocean basins.can Itbe arrangedwas this into a sequence of stages called the Food for Thought: ern United States in terms of the method of multiple 1 Much of the description of the events immediately before and a er the impact 3.5.1is derived Biogeography: from Alvarez, W. 1997.distribution ing. Hypotheses and theories of mountain building tectonic cycle: East African Rift Valley, Red Sea, Atlan- which1. Whattend is the to evidence flow forout the solarover nebula the hypothesis Earth’s as surface rather than type ofchanged evidence radically that over the was past twoinitially centuries, used and to infertic the Ocean, former Paci c Ocean, and suture (Himalayas). Not Further Activities In and Outside of Class working hypotheses (see Chapter 1). Princeton, NJ: Princeton University Press. their development is a prime example of how scien- explodingof plantsopposed violentlyto the originaland Kant-Laplace into animals the hypothesis? atmosphere. over Fissure Earth’s eruptions existence of the supercontinent Pangaea and toall supportrift valleys become the seaways, however; many have 4. How did preadaptation in early primates later affect tists work and think. become failed rift valleys or aulacogens, down which 1. Construct a table of the hypotheses described in the the evolution of humans? 2. How do the inner planets, including Earth, di er from the nnThe discovery of radioactivity led to more modern are therefore presumably incapable of pumping enormous hypothesis of continental drift. These and othersome broad of the world’s effects major rivers such as the Amazon text for the origin of the Basin and Range. List the Why is the fossil record of humans so hotly debated? surfaceo u t e r p la n e t s ? theories of mountain building. Of these, it is Alfred ow. The tectonic cycle has occurred a number of hypotheses down the left side and place a heading at 5. Plesiadapis amounts of iridium and dust into the atmosphere; explosive of theWegener’s tectonic hypothesis cycle of on continental Earth drift—based systems on and sedimentary envi- Of the different hypotheses for human evolution, Nevertheless, sea level was falling and possibly Earth was Why The mightbiosphere carbonaceous chondrites is composed have been of an the total living biota times during Earth’s history, each cycle spanning sev- the top titled “Evidence.” Include in that column both 6. of India, volcanism3. is required to pump material high enough into the ronmentsa variety will of evidence—that be discussed paved in the the way last for part the of this chapter.eral hundred million years. which one do you favor and why? ; modern theory of plate tectonics. Initially, Wegener’s the geologic evidence and the forces inferred from the cooling somewhat toward the end of theDeccan Cretaceous, Traps and both H important(living source organisms) of water for early of Earth? Earth, ranging from the smallest nnBased on the tectonic cycle, continental margins and 7. What is the signi cance of the nding of Figure 13.47 atmosphere for it to spread over the planet. hypothesis was roundly criticized because he could plate boundaries can change through time. There are evidence. Then, to the right place a column titled “Suc- in both North America and Europe? not identify a mechanism to make continents drift. factors might have already stressed ecosystems before their final bacteria to the largest trees and whales. However, organisms two basic types of continental margins: active and cess of the Hypothesis” with two columns underneath Quite frequently, new species of humans are based Consequently, continents (or at least many geologists’ passive. Passive continental margins, like those along for each of the main regions of the Basin and Range 8. demise. Huge outpourings of lava, the 3.5.2 minds) Energy remained relationships “ xed” until the work of Harry Hess niches of species on a single fossil fragment such as a jaw fragment. are not uniformly distributed over the planet. This basic the Atlantic Ocean, accumulate sediment along their emphasized in the text: Northern (N) and Southern (S). in the 1950s, which proposed the process of seaoor margins. Active margins, like those along the Paci c How can an entire new species be inferred from a also occurred about the time of the extinctions ( Réunion observation CONCEPT was a cornerstone AND REASONING of speciesCharles—has Darwin’s CHECKS a certain theory range of The flux of matter and energy within ecosystems is For each hypothesis, indicate whether it satisfactorily 7.5 The Hadean: Origin of spreading as a mechanism to move continents. Ocean’s ring of re, are sites of subduction, volcanism, single fragmentary fossil? (Hint: See Chapter 4 for the term “trap” refers to the step-like appearance of the vol- evolution (see Chapter 5). I nnIndetermined the 1960s, the detection by the of magneticcharacteristic seaoor and earthquakes. explains the evidence within the region (+), does not Cuvier’s correlation of parts.) canics). The Deccan Traps formed as the Indian subcontinent Each type of organism—or stripes corroborated seaoor spreading and provided nnPlate boundaries are classi ed into three basic catego- explain it one way or the other (0), or contradicts it (–). withinthe the mechanism ecosystem. of continental The drift term that had “niche” eluded refers tories: the convergent particu- (associated with sea oor trenches), Discuss your results in terms of the method of multiple , dust, and iridium Earth1. Volcanism and has been implicatedMoon in several mass Wegener. Seaoor spreading alsotrophic corroborated (food, Hess’s energy) relation- rifted away from Gondwanaland and moved2 over the of physical environmental factors within which it can live lar role or function of a species within an ecosystemdivergent (associatedand is with rifting), and transform, working hypotheses (see Chapter 1). (see Chapter 2). Massive volcanism is thought to e x t in c t io n s . W h ic h o n e s ? views about the formation of guyots, heat ow beneath which are associated with offsets of mid-ocean ridges. hotspot and reproduce its own kind. It is this tolerance to environ- mid-ocean ridges, and the destruction of seaoor in Which normally causes sea level to change faster: the 7.5.12. Diagram Earth’s the test of a meteor earliest impact as the causal evolution agent defined primarily by the nnConvergent boundaries are themselves of three types: 2. have pumped enormous amounts of CO mental factors that largely determines the biogeographic dis- trenches. Rearranging the continents into different volcanic island arc (for example, Japan), continental advance and retreat of glaciers or the movements of of the Late Cretaceous mass extinction in terms of the shipspositions of the species,also began to or make “who sense eats of apparent whom.” polar The nichesisland of arc the (for example, the Cascades), and collisional continents? into the atmosphere, causing climate change and perhaps Calculations suggest it would have taken at least wandering curves. tribution scientific methodof different diagrammed species. in Chapter Temperature1 (see Box 13.3). is considered to different speciesfood of chain a community or food web. can It be is these diagrammed energetic(Himalayas). as making the biosphere more susceptible to impact. Thus, an J 100 million years for the proto-Earth to grow from nnConsequently, what had been known as continental nnThe three types of convergent plate boundaries paral- be the most important factor determining the distribution “links”drift in was a wedded to seaoor spreading to produce the lel the different types of orogenesis and the formation . As theory of plate tectonics. impact might have been the last straw that broke the back aboutof different 10 km species in diameter because to it its affects present the size. rates This of biochem- phase relationships that organize the species inhabitingof major an geologic area structures such as faults and folds: Hadean Eon nnToday, plate tectonics is recognized as an integral com- island arcs only, plate collisions without continents, of the biosphere and caused the final collapse of ecosystems occurredical pathways during such the as first photosynthesis 0.8 billion years and of respiration; the development such into communitiesponent of Earth’s systems. and Weecosystems. know that Earth’s lith- and continent–continent collisions. 497 osphere (the crust and uppermost mantle)food consists (or energy) pyramids Extinction at the end of the Cretaceous. Other workers, however, point out ofprocesses Earth, stretching tend to be to characteristic about 3.9 to of3.8 each billion species. years On ago. land, This 24/10/16 11:42 amThe energetic relationships of food chains andnnAs orogenesis webs occurs, smaller pieces of crust with 15.7 of about 15 large and small plates that are moved by distinctive geologic features (rock type, fossils, the Deccan Traps represent relatively gentle fissure eruptions, firstrainfall phase is alsoof Earth’s important history because is known animals as the and plants must can alsothe production be arranged of new seaoor into at mid-ocean ridges. paleomagnetic directions) called microcontinents or Forming portions). The of thedifferent plates are levels continents. of Thethe food pyramidexotic terranes show can be sandwiched between the larger Mesozoic Era autotrophs or pro- 24/10/16 11:49 am themake name up for implies, water Earthloss due was to quite respiration hot. The and Hadean transpiration. rep- (Figure plates 3.24 move over the asthenosphere of the mantle. continents. Chapter 13 Beneath the mantle are an outer uid and a solid inner resentsIn the oceansthe beginning the salinity of the and much oxygen longer content Precambrian, of the water which how food (energy, matter) is passed from onenn Nogroup one has of ever organ- observed the tectonic cycle because 414 iron and nickel-rich core that generate Earth’s mag- of the immense amounts of geologic time involved in © Datacraft/age fotostock. stretchesalso affect from the the distribution birth of Earth of organisms, to about especially540 million close years netic eld. isms to another in a community. Plants ( its completion, but it can be pieced together based on nnAlthough) occur convection at the cells base. are widely During viewed photosynthesis as mov- observations energy of modern tectonic settings. ago,to shore when where the first large good rivers fossils enter. ofeurytopic theModern Phanerozoic species and more that,Eon widely (“timefor179 ducersing the plates, several hypotheses have been proposed ofexample, apparent live life”) in temperatebegin to appear and higher consistently. latitudes—on land to explain how the seaoor actually moves: (1) slab- from lightpull, in whichis used a descending by plants slab pulls (or the producers) rest of slab to combine car- Comet Hale-Bopp. The two tails range from 10 to or in the oceans—tendcosmopolitan to be —because they must with- bon dioxidebehind it downward; from the (2) ridge-push,atmosphere in newly with formed water to produce one The Hadean: Origin of Earth and Moon ocean crust as spreading centers pushes the slab ahead 9781284457162_CH13_PASS02.indd FIGURE 7.14 414 distributed—or7.5 molecule of sugar and oxygen, which is released as a byprod- 9781284457162_CH15_PASS02.indd 497 14/10/16 5:34 pm 15 million miles in length. Comets are “dirty snowballs” and might stand greater extremes of temperature and other factors that uct into the atmosphere. Energy from sunlight is occurstored at thein h a v e b r o u g h t w a t e r t o t h e e a r ly E a r t h . Thechange Student with Experiencethe seasons. By contrast, many other species are the chemical bonds of the sugar, whereasHerbivores carbon dioxide is xvi stenotopic , or narrowly tolerant of environmental change. taken out of the atmosphere and sequesteredSecondary in the consumers reservoirs These taxa tend to be concentrated in, or endemic to, certain of living and dead organic matter. areas because of their narrower tolerances. Many tropical © Jones & Bartlett Learning, LLC, an Ascend Learning Company.level immediately NOT occurFOR above SALE at the producers. OR next DISTRIBUTION higher level above herbivores 25/10/16 3:37 pm species of plants, insects, and corals are stenotopic and are (carnivores) at the apex of the pyramid. Although Plate Tectonics endemic to certain regions of Earth. topChapter carnivores 2 and52 9781284457162_FMxx_00i_xxii.indd 16 Each continent, ocean basin, or sea tends to have its the conversion of light energy to plant biomass varies, it is 07/11/16 1:47 pm 9781284457162_CH07_PASS02.indd 179 own distinctive biota. On land, larger regions of each con- roughly about 10% efficient. Moreover, as the energy stored ). These broad bands, tinent are characterized byFigure distinct 3.23 bands of vegetation and biomes ( 9781284457162_CH02_PASS04.inddin plant biomass 52 is passed from one level to the next of the deserts called pyramid, energy is lost, so that only so many levels can be which tend to circle the globe on land, tend to correspond to supported. This means that only 10% of the original light differences in the amount of solar radiation and precipitation energy received by the plant is converted to plant biomass. reaching Earth’s surface, as described earlier in the chapter. Now assume that each level of a food pyramid is only 10% Each continent in turn represents a particular biogeographic region. Similarly, there is a steep temperature gradient in the surface waters of the open oceans. Surface water tem- 25/10/16 3:40 pm peratures at the equator can reach 30°C, whereas those near Earth Systems: Processes and Interactions Chapter 3 76

9781284457162_CH03_PASS04.indd 76 every 100,000 years; (2) obliquity (“tilt”) of Earth’s axis toward or away from the sun, which affects the amount of solar radiation impinging on the northern hemisphere and which completes one cycle every and erosion all over the world. Also, the calcite com- 40,000 years; and (3) precession of the equinoxes pensation depth tended to deepen as sea level fell. about every 19,000 to 23,000 years, which affects the nnA permanent polar ice cap began to grow on Ant- occurrence of the seasons within Earth’s orbit around arctica as it continued to move over the South Pole, the sun. which led to a lowering of sea level. nnThe growth of ice sheets in the northern hemisphere nnIce caps also appeared in the northern hemisphere, might have caused forests to further shrink and grass- based on ice-rafted debris about 2.8 million years old in tens-of-millions of years before the end of the Cretaceous lands to expand. With the continued expansion of period (see Further Reading). In any case, the demise of the deep-sea cores taken off the British Isles. This followed grasses came further diversication of artiodactyls. dinosaurs gave the mammals the opportunity to diversify in about 700,000 years after the rise of the Isthmus of Similarly, according to the turnover pulse hypothesis, the Cenozoic (see Chapter 14). There is now a general con- Panama, which is thought to have blocked the ow of shrinking forests caused ancient human ancestors, sensus that one or more meteors hit Earth at the end of the many taxa on land and in the sea could not tolerate. Indeed, warm-water currents from the Atlantic into the Pacic. the Late Cretaceous extinctions are associated with one or or hominids, which were arboreal, to leave forests Cretaceous, and that impact was the primary cause of the The diversion of warm waters northward into the Gulf final demise of the dinosaurs and other taxa on land and in more iridium layers that presumably settled out with the dust for grasslands. On the other hand, human evolution the sea. The sudden injection of dust high into Earth’s atmo- after the impact(s). More important, well-developed shocked of Mexico and the western Atlantic Ocean transported might have resulted from changes in behavior. sphere is thought to have caused rapid global cooling, which mineral assemblages and microtektites occur at the end of warm, moist air to higher latitudes, where it began to nnIn either case, our ancestors eventually began to walk the Cretaceous Period. The intensity of metamorphism of precipitate as snow and ice. With the appearance of upright. As hominids evolved, different populations the shocked minerals could only have occurred by a sud- ice caps in the northern hemisphere, production of den increase in intense pressures and temperatures like those might have coexisted in the same habitats and might generated during an impact (see Chapter 3 and North Atlantic Deep Water began, which, along with have migrated a number of times to Asia and even- the production of Antarctic Bottom Water, resulted in tually to Europe. As humans spread across the globe increasing oxygenationnn Key ofTerms the deep oceans. List—A list of duringthe thekey Holocene, terms they frommight have contributed to nn Review Questions—These end-of-chapter ques- B O X 1 3 . 3 Box 13.3 Late Cretaceous Extinctions and the Scientific Method ). nnAfter the northerneach hemisphere chapter ice sheets is wereprovided estab- to helpthe demise students of different speciesreview of large mammals and tions are great for homework assignments or self- lished, they waxed and waned in response to the ightless birds. M o s t m a s s e x t ni c t oi n s a p p e a r t o b e s o m e h o w r e la t e d amount of solar radiation reaching Earth’s surface. to the tectonic cycle. However, the Late Cretaceous new vocabulary. guided study. extinctions involved—and may well have resulted Cycles of solar radiation are thought to represent primarily from—an impact, as indicated by the Milankovitch cycles of solar radiation that occur at nI ti ai ly , a d a r k s e d mi e n t a r y la y e r c o n t a ni ni g a three dominant periods: (1) eccentricity (or “elliptic- occurrence of shocked mineral assemblages high concentration of the element iridium was found (Box Figure 13.3A ) . W h e r e a s t h e mi p a c t h y p o t h e s si near Gubbio, Italy, almost by accident (see Chapter 1). ity”) of Earth’s orbit that completes one cycle about certainly arouses our imaginations, how the The iridium layer also occurred at the time of the hypothesis came to be widely accepted by the mass extinction at the end of the Cretaceous Period scientific community is also a prime example of about 65 million years ago, during which dinosaurs how scientific investigation works (see Chapter 1). and many other organisms became extinct. Iridium is species Moreover, the corroboration of the hypothesis not normally found in rocks of Earth’s crust and could stereoscopic vision paved the way for the acceptance of extraterrestrial have come from only two sources: volcanoes fed by overkill hypothesis impacts as important—even extraordinary—agents strepsirrhinesReview Questions the mantle, which is enriched in iridium, or from an oxygen isotopes 5. How might have tectonism contributed to the growth of geologic, climatic, and biospheric change. It also extraterrestrial body. The hypothesis was that the Key Terms Gulf Stream summer solstice of glaciers over both poles of Earth? Pacific plate 1. How do Paleogene and Neogene events differ from radically altered—once and for all—earth scientists iridium layer was generated by a meteor enriched supraorbital ridge What is the evidence for the advance and retreat of haplorhines each other? Make a chart labeled Paleogene and Neo- 6. unquestioned acceptance of Lyell’s dogma of slow, in iridium. The impact presumably threw a gigantic aquifer precess Holocene terminations northern hemisphere glaciers from land? From the gradual change to a broader doctrine that recognized dust cloud into Earth’s stratosphere that suddenly precession of the equinoxes gene across, and down the left side of the chart list Basin and Range Province tilt deep sea? that Earth systems processes vary through time and in cooled the planet, causing extinction; the blockage horst-and-graben the following: (a) continental, (d) movements, ocean circulation, (b) sea C3 grasses Primates 2 7. How do the three major Milankovitch frequencies r a t e (s e e C h a p t e r 1 ). of sunlight also shut down marine photosynthesis Juan de Fuca plate turnoverlevel, pulse (c) atmospheric CO Rio Grande Ri interact to produce climate change? Do all three fre- causing a C4 grasses ungulates(e) oxygen, (f) plankton, (g) calcite compensation Strangelove Ocean ( n a m e d a e r t h e Lake Bonneville quencies always accentuate glaciation or warming? character of the same name in a famous movie) in Coast Ranges San Andreas Fault depth, (h) terrestrial plants, and (i) terrestrial animals. mammoths winter solstice Why or why not? which there was a sudden, strong shi in carbon Sierra Nevada On a map of North America or another continent(s) of Cocos plate 2.wobble How does the evolution of humans resemble that of isotope ratios to much lower values (see Chapter 9; Milankovitch cycles the world, nd the following features that formed dur- 8. diluvial theory single origin other taxa, such as the horse? What factors contrib- Box Figure 13.3B ) . moraines ing the Neogene and discuss how they formed: Ama- East Pacific Rise single species hypothesis uted to the evolution of humans? A p r e d ci t oi n m a d e fr o m t h e h y p o t h e s si w a s t h a t multiregional evolution zon rain forest, Amazon River, Arabian Peninsula, Aral if an impact were responsible for the Late Cretaceous Sixth Extinction Evaluate the different hypotheses for human evo- eccentricity hypothesis Sea, Basin and Range, Cascade Mountain Range, Coast 9. extinctions, an iridium layer should be found all over slab gap hypothesis lution for their strengths and weaknesses: multire- Farallon plate obliquity Ranges, East African Rift Valley, Front Range, Greater the world in rocks of exactly the same age. Scientists gional, single species, and turnover pulse. tested the hypothesis by exploring for the iridium layer Front Range Antilles, Gulf of California, Himalayas, Isthmus of Pan- Out of Africa hypothesis What is the difference between a species and a race? all over the world, on land and in deep-sea cores, glacial erratics ama, Mississippi River, Rio Grande Rift, San Andreas 10. where the rocks were of the right age. The hypothesis 11. What was happening on Earth about 10,000 to Great American Interchange Fault, Sierra Nevadas, and Yellowstone hotspot. was corroborated: the Late Cretaceous iridium layer 11,000 years ago? 3. What was the effect of the uplift of the Himalayas on is now known not only from Gubbio, Italy, but also How might have tectonism contributed to the growth global climate? (See also Chapter 2.) from Stevns Klint (Steven’s Cli ) near Copenhagen, 5. of glaciers over both poles of Earth? What was the effect of the rise of the Isthmus of Panama BOX FIGURE 13.3A Denmark; El Kef, Tunisia, in north Africa; and El 4. What is the evidence for the advance and retreat of on global climate and life on land and in the oceans? a n a s te ro di w tih E a rt h . An artist’s visualization of © the Gl0ck/ShutterStock, impact Inc. of Mimbral, Mexico (to name only a few of the more Review Questions 6. famous and intensively studied localities), as well as in northern hemisphere glaciers from land? From the many deep-sea cores (see Box Figure 13.3B ) . 1. How do Paleogene and Neogene events differ from deep sea? each other? Make a chart labeled Paleogene and Neo- How do the three major Milankovitch frequencies 7. 24/10/16 11:49 am 412 gene across, and down the left side of the chart list interact to produce climate change? Do all three fre- Chapter 13 2, (d) ocean circulation, Mesozoic Era the following: (a) continentalnn Food movements,for Thought (b)The sea Cenozoic —More Era: Thequencies Neogene in-depth always Period accentuate than glaciationthe Review or warming? nn Sources and Further Reading—The list of refer- level, (c) atmospheric CO Chapter 15 Why or why not? 9781284457162_CH13_PASS02.indd 412 (continues) (e) oxygen, (f) plankton,496Questions, (g) calcite compensation the Food for Thought activities are great Food for encesThought: for the chapter is a great place for students to 8. How does the evolution of humans resemble thatFurther of Activities In and Outside of Class depth, (h) terrestrialfor plants, individual and (i) terrestrial or animals. group assignmentsother taxa, such as in the horse?or out What of factors the contrib- begin additional research into3. Describe special the tectonics topics. and sedimentation of the west- On a map of North America or another continent(s) of ern United States in terms of the method of multiple 2. uted to the evolution of humans? Construct a table of the hypotheses described in the the world, nd theclassroom. following features Theythat formed will dur- challengeEvaluate students the different to hypotheses think for criti- human evo-1. working hypotheses (see Chapter 1). 9. text for the origin of the Basin and Range. List the ing the Neogene and discuss how they formed: Ama- lution for their strengths and weaknesses: multire- How did preadaptation in early primates later affect 9781284457162_CH15_PASS02.inddcally about 496 the material presented in the chapter. hypotheses down the left side and place a heading at 4. zon rain forest, Amazon River, Arabian Peninsula, Aral gional, single species, and turnover pulse. the evolution of humans? the top titled “Evidence.” Include in that column both Sea, Basin and Range, Cascade Mountain Range, Coast What is the difference between a species and a race? Sources and Why is the fossil record of humans so hotly debated? 24/10/16 11:42 am 10. the geologic evidence and the forces inferred from the 5. Ranges, East African Rift Valley, Front Range, Greater What was happening on Earth about 10,000 to Further Reading Of the different hypotheses for human evolution, 11. evidence. Then, to the right place a column titled “Suc- 6. Antilles, Gulf of California, Himalayas, Isthmus of Pan- 11,000 years ago? which one do you favor and why? Plesiadapis cess of the Hypothesis” with two columns underneath ama, Mississippi River, Rio Grande Rift, San Andreas Alroy, J. 2001. A multispecies overkill simulation of the What is the signi cance of the nding of for each of the main regions of the Basin and Range 7. Fault, Sierra Nevadas, and Yellowstone hotspot. end-Pleistocene megafaunal mass extinction. in both North America and Europe? emphasized in the text: Northern (N) and Southern (S). 3. What was the effect of the uplift of the Himalayas on 292, 1893–1896. Quite frequently, new species of humans are based For each hypothesis,Asfaw, B. etindicate al. 2002. whether Remains ofit satisfactorily 8. global climate? (See also Chapter 2.) Science, on Leonard,a single W. fossil R. 2002. fragment Food for such thought: as a Dietaryjaw fragment. change explains the evidenceMiddle withinAwash, Ethiopia.the region Nature (+),, 416 does, 317–320. not 4. What was the effect of the rise of the Isthmus of Panama Homo erectus from Bouri, How canwas aan driving entire force new in humanspecies evolution. be inferred from a explain it oneBaldridge, way or W. the S. other2004. (0), or contradicts it (–). on global climate and life on land and in the oceans? singleAmerican fragmentary, 287(6):106–115. fossil? (Hint: See Chapter 4 for Discuss your resultsA journey in throughterms twoofGeology thebillion method ofyears the Americanof plate-tectonicof multiple Southwest: hishis- Monastersky, R. 1996. Out of arid Africa. tory. Cambridge, UK: Cambridge University Press. Cuvier’s correlation of parts.) Scientific of it; (3) gravity slide, in which a slab slowly “slides” working hypothesesBower, B. 1999. (see DNA’s Chapter evolutionary 1). dilemma. 150(5, August 3), 74–75. Monastersky, R. 1999. The killing fields: What robbed down the side of a spreading center, pushing the slab 2. Which normally causes sea level to change faster: the Science News, News, 155(6, February 6):88–90. Summary ahead of it; and (4) suction from the descending por- advance Bower,and retreat B. 2001. of(6, Fossilglaciers February skull or 6):88–90.diversifies the movements family tree. of the Americas of their most charismatic mammals? tion of a plate. Science Science News, 156(23):360–361. continents?News, 159(12, March 24), 180. nnThe theory of plate tectonics really began with nnBased on plate tectonics, different features of the planet , 159(12, March 24), 180. Murphy, J. B., Oppliger, G. L., Brimhall, G. H., and Hynes, early ideas about orogenesis, or mountain build- 3. Describe the tectonics and sedimentation of the west-Bower, B. 2002. Evolution’s surprise: Fossil find uproots can be arranged into a sequence of stages called the Food for Thought: ern United States in terms of the method of multiple Science A. 1999. Mantle plumes and mountains. ing. Hypotheses and theories of mountain building tectonic cycle: East African Rift Valley, Red Sea, Atlan- our early ancestors. Science News, 162(2):19. Scientist, 87(2):146–153. Brunet, M. et al. 2002. A new hominid from the Upper changed radically over the past two centuries, and tic Ocean, Paci c Ocean, and suture (Himalayas). Not Further Activities In and Outside of Class working hypotheses (see Chapter 1). Ni, Xijun, et al. “The oldest known primate skeleton their development is a prime example of how scien- American all rift valleys become seaways, however; many have How did preadaptation in early primates later affect Miocene of Chad, central Africa. and early haplorhine evolution.” tists work and think. 4. become failed rift valleys or aulacogens, down which 1. Construct a table of the hypotheses described in the the evolution of humans? 145–151. (2013):60–64. nnThe discovery of radioactivity led to more modern Cerling, T. E., Chritz, K. L., Jablonski, N. G., Leakey, M. G., some of the world’s major rivers such as the Amazon text for the origin of the Basin and Range. List the Why is the fossil record of humans so hotly debated? Nature, Pastor, J., and Moen, R. A. 2004. EcologyNature of ice-age, theories of mountain building. Of these, it is Alfred ow. The tectonic cycle has occurred a number of hypotheses down the left side and place a heading at 5. Plesiadapisand Manthi, F. K. 2013. Diet of Theropithecus from418 , 498.7452 Wegener’s hypothesis of continental drift—based on 6. Of the different hypotheses for human evolution, extinctions. Nature, 431, 639–640. times during Earth’s history, each cycle spanning sev- the top titled “Evidence.” Include in that column both 4 to 1 Ma in Kenya. Roberts, R. G. et al. 2001. New ages for the last Australian a variety of evidence—that paved the way for the eral hundred million years. which one do you favor and why? emy of Sciences, www.pnas.org/cgi/doi/10.1073/pnas the geologic evidence and the forces inferred from the Proceedings of the National Acad- megafauna: Continent-wide extinction about 46,000 modern theory of plate tectonics. Initially, Wegener’s nnBased on the tectonic cycle, continental margins and What is the signi cance of the nding of .1222571110 , www.pnas.org/cgi/doi/10.1073/pnas 7. years ago. Science, 292, 1888–1892. Extinction 497 hypothesis was roundly criticized because he could plate boundaries can change through time. There are evidence. Then, to the right place a column titled “Suc- in both North America and Europe? Chester, Stephen G. B., et al. Oldest known euarchontan 15.7 not identify a mechanism to make continents drift. Ruddiman, W. F., and McIntyre, A. 1976. Northeast two basic types of continental margins: active and cess of the Hypothesis” with two columns underneath tarsals and affinities of Paleocene Purgatorius to PriPri- Consequently, continents (or at least many geologists’ 8. Quite frequently, new species of humans are based Atlantic paleoclimate changes over the past 600,000 passive. Passive continental margins, like those along for each of the main regions of the Basin and Range mates. minds) remained “ xed” until the work of Harry Hess on a single fossil fragment such as a jaw fragment. Proceedings of the National Academy of Sciences, years. In R. M. Cline and J. D. Hays (eds.), the Atlantic Ocean, accumulate sediment along their 112.5(2015):1487–1492. in the 1950s, which proposed the process of seaoor emphasized in the text: Northern (N) and Southern (S). (2015):1487–1492. gation of Late Quaternary paleoceanography and paleo- margins. Active margins, like those along the Paci c How can an entire new species be inferredDayton, from L. a 2001. Mass extinctions pinned on ice age 24/10/16 11:49 am spreading as a mechanism to move continents. For each hypothesis, indicate whether it satisfactorily single fragmentary fossil? (Hint: See Chapter 4 for climatology (pp. 111–146). Special Publication 145. Ocean’s ring of re, are sites of subduction, volcanism, hunters. Science, 292, 1819. Investi- nnIn the 1960s, the detection of magnetic seaoor and earthquakes. explains the evidence within the region (+), does not Cuvier’s correlation of parts.) Science Boulder, CO: Geological Society of America. Demenocal, P. B. 2011., 292 Climate, 1819. and human evolution. Sonder, L. J., and Jones, C. H. 1999. Western United stripes corroborated seaoor spreading and provided nnPlate boundaries are classi ed into three basic catego- explain it one way or the other (0), or contradicts it (–). the mechanism of continental drift that had eluded Science, 331, 540–542 ries: convergent (associated with sea oor trenches), Discuss your results in terms of the method of multiple 9781284457162_CH15_PASS02.indd, 331 497, 540–542 States: How the west was widened. Wegener. Seaoor spreading also corroborated Hess’s Gibbons, A. 2011. Skeletons present an exquisite divergent (associated with rifting), and transform, working hypotheses (see Chapter 1). Earth and Planetary Sciences, 27, 417–462. views about the formation of guyots, heat ow beneath which are associated with offsets of mid-ocean ridges. paleo-puzzle. Science, 333, 1370–1372. Stringer, C. 2003. Out of Ethiopia. Annual Review of Which normally causes sea level to change faster: the Guo, Z. T. et al. 2002.Science Onset of Asian desertification by mid-ocean ridges, and the destruction of seaoor in nnConvergent boundaries are themselves of three types: 2. , 333 Stuart, A. J., Kosintsev, P. A., Higham, T. F. G., and Lis- trenches. Rearranging the continents into different advance and retreat of glaciers or the movements of 22 Myr ago inferred from loess deposits in China. Nature, volcanic island arc (for example, Japan), continental ter, A. M. 2004. Pleistocene to Holocene423 extinc-, 692–695. positions also began to make sense of apparent polar Nature, 416, 159–163. island arc (for example, the Cascades), and collisional continents? , 416 tion dynamics in giant deer and woolly mammoth. wandering curves. Imbrie, J., and Imbrie,, 159–163. K. P. 1979. (Himalayas). Nature, 431, 684–689. nnConsequently, what had been known as continental nnThe three types of convergent plate boundaries paral- tery. Short Hills, NJ: Enslow Publishers. Tattersall, I. 1997. Out of Africa again … and again? drift was wedded to seaoor spreading to produce the lel the different types of orogenesis and the formation Leakey, R. and Lewin, R. 1995. Ice ages: Solving the mys- theory of plate tectonics. entific American, 279(4):60–67. of major geologic structures such as faults and folds: terns of life and the future of humankind. New York: Tattersall, I. 2000. Once we were not alone. nnToday, plate tectonics is recognized as an integral com- island arcs only, plate collisions without continents, The Sixth Extinction: Pat- Doubleday Dell. American, 282(1):56–62. Sci- ponent of Earth’s systems. We know that Earth’s lith- and continent–continent collisions. Leakey, M. G. et al. 2001. New497 hominid genus from east- osphere (the crust and uppermost mantle) consists Extinction Tavaré, S., Marshall, C. R., Will, O., Soligo, C., and Mar- nnAs orogenesis occurs, smaller pieces of crust with 15.7ern Africa shows diverse middle Pliocene lineages. Scientific of about 15 large and small plates that are moved by distinctive geologic features (rock type, fossils, tin, R. D. 2002. Using the fossil record to estimate the production of new seaoor at mid-ocean ridges. Nature, 410, 433–440. the age of the last common ancestor of extant pri- paleomagnetic directions) called microcontinents or Leakey, M. G., Spoor, F., Dean, M. C., Feibel, C. S., Antón, Forming portions of the plates are continents. The exotic terranes can be sandwiched between the larger mates. Nature, 416, 726–729. S. C., Kiarie, C., and Leakey, L. N. 2012.24/10/16 New 11:49 fossils am plates move over the asthenosphere of the mantle. continents. Templeton, A. R. 2002. Out of Africa again and again. from Koobi Fora in northern Kenya confirm taxo- Beneath the mantle are an outer uid and a solid inner nnNo one has ever observed the tectonic cycle because Nature, 416, 45–51. nomic diversity in early iron and nickel-rich core that generate Earth’s mag- of the immense amounts of geologic time involved in Vekua, A. et al. 2002. A new skull of early netic eld. its completion, but it can be pieced together based on Homo. Nature, Dmanisi, Georgia. Science, 297, 85–89. nnAlthough convection cells are widely viewed as mov- observations of modern tectonic settings. 488, 201–204. Wilson, E. O. 1992. ing the plates, several hypotheses have been proposed Homo from Belknap Press. The diversity of life. Cambridge, MA: to explain how the seaoor actually moves: (1) slab- pull, in which a descending slab pulls the rest of slab 498 behind it downward; (2) ridge-push, in newly formed Chapter 15 The Cenozoic Era: The Neogene Period ocean crust as spreading centers pushes the slab ahead 9781284457162_CH15_PASS02.indd 497

9781284457162_CH15_PASS02.indd 498 The Student Experience xvii

25/10/16 3:37 pm © Jones & Bartlett Learning, LLC, an Ascend Learning Company. NOT FOR SALE OR DISTRIBUTION 24/10/16 11:49 am Plate Tectonics Chapter 2 52 9781284457162_FMxx_00i_xxii.indd 17 07/11/16 1:47 pm

9781284457162_CH02_PASS04.indd 52 nn New and Revised Art and Photos—The art in this second edition, including over 150 new images and ). These types of plate 150 revised illustrations,Figure 2.21 has been signi cantly improved to supportconvergent, students or transform ( as they absorb new information. boundaries are also found on the ocean floor.

Divergent plate boundaries faults exhibit relative movement in the opposite direction, that Divergent plate boundaries are associated with rifting. is, the rocks on the other side of the fault from where one is Initially, rifting of the crust occursupward to produce movement rift ofvalleys mantle on standing move to the left. Another phenomenon is also commonly associatedfolding . Folds land or along the crests of mid-ocean ridges (Figure 2.21 ). anticlines the Divergent margins mark the with tectonism and the deformation of rocks, especially by Neptune Volcanic material involved in seafloor spreading and the formation of Uranus TABLE 7.1 island arc large-scale thrust faulting during orogenesis: seafloor crust. Thus, divergent plate boundaries are exten-Saturn Major features of the planets Jupiter are of two types: anticlines and synclines. In sional, or pull-apart, in nature andMars tend to be associated with strata dip away from the main axis of the fold, with the old- Earth synclines just the opposite Venus est strata found in the core of the anticline, and the youngest Mercury strata on its crest and sides. In 4,878 12,104 12,756 6,794 142,800 120,540 51,200 49,500 occurs: the strata dip toward the center of the fold, andFolded the rock Fault strata found along the axis of the syncline areDiameter younger (km) than Diameter in relation to Earth 38% 95% X 53% 1,120% 941% 401% 388% strata farther away from the 5.43 5.24 5.52 3.9 1.3 0.7 1.2 1.6 Figure 2.19) . Anticlines Mass in relation to Earth 5.5% 82% X 10.7% 31,780% 9,430% 1,460% 1,720% axis ( 3) and synclines frequently Density (g/cm 0.0 177.4 23.4 25.2 3.1 26.7 97.9 29 occur adjacent to one another Rotation period (days) 58.6 –243 0.997 1.026 0.41 0.43 –0.72 0.67 because both form during Inclination of axis of rotation 38% 91% X 38% 253% 107% 92% 118% folding. to equator (degrees) Sometimes folds become Surface gravity in relation to oversteepened and come to lie Earth Morrison Formation (a) Sedimentary rocks squeezed by compression on their sides. Thrust faults AU = astronomical unit, or the distance between the Earth and sun. Retreating Sundance Sea Figure 23.16A (p. 610). are commonly associated with Folding and thrusting Franciscan Group this type of folding. Under planetesimal’s collision with other objects and their fragmen- Data from: Monroe, J. S., and Wicander, R. 1997. The Changing Earth: Exploring Geology and Evolution, 2nd ed. Belmont, CA: West/Wadsworth. these conditions the compres- tation. Alternatively, because of Jupiter’s size, perhaps Jupi- (a) sional forces finally become so great that insteadter’s gravitational of continued field was simply so strong it prevented the folding, the rocks fracture and a hanging wallformation moves of over a planet a from asteroid debris that was already present. © MarcelClemens/Shutterstock, Inc. footwall at low angles. Spectacular folds). of this typeIndeed, are asteroids seen are not thought to have originated (Figure 2.20 (a) in mountain rangesnappes all over the world; in thefrom Alps, large they planets are for two main reasons. First, high pres- referred to as sure minerals that typicallyMeteorites form within are fragmentslarge planets found are onnot present in meteorites. 2.4.3 Types of plate boundaries associated Earth with of active extraterrestrial con- bodies, including asteroids, that col- lided with Earth (Figure 7.13). Some meteorites have been Theplate boundaries radiometrically dated at approximately 4.5 billion years, G H tinental margins can be categorizedindicating as divergent, these particular meteorites date from about the time of the formation of the solar system. Second, strong

Hinge line Axial surface

Limb Anticline

Anticline

Syncline 379 (b) Exposure of the Morrison Formation. (c) (b) © Shifted/Shutterstock, Inc. Data from: http://www.glossary.oil eld.slb.com/DisplayImage.cfm?ID=10. Types of meteorites. From top to bottom are Orogeny, Sea Level, and Sedimentation Courtesy of NASA/JPL. Seaways, tectonics, and sedimentation in the interior of western North America during the Jurassic. The Morrison FIGURE 7.13 13.4 (a) shown: stoney-iron, iron, and stoney meteorites. FIGURE 13.17 24/10/16 11:42 am (b) Formation, which is molasse shed from the west that filled the Sundance Sea. (b) Exposure of the Morrison Formation. F I G U R E 2 . 1 9 The features of anticlines and synclines. The central PRESENT DAY Relatively weak meltwater input Jupiter’s red spot might represent a gigantic storm Ocean Cross section of highly-folded thrust Photo sheets of the Alps showing circulation may portion of an anticline or syncline is known as its axis. In anticlines, F I G U R E 2 . 2 0 (a) (b) Photo of the Alps showing 14/10/16 5:34 pm Warm FIGURE 7.12 temporarily the strata dip away from the axis of the anticline,that with has the persisted oldest for hundreds ofin years. the Alps. The huge blocks of rocks that have been thrust over slow or stop if An Extraordinaryyounger rocks Beginning: are called Hadean nappes. and Archean Circulation there is enough strata being found in the core of the anticline and the youngest on eventually meltwater input its crest and limbs. In synclines, just the opposite occurs:Chapter the strata 7 e x t e n s iv e f o ld in g . returns to 178 Elevator travels along normal by dip toward the center of the syncline and the strata found along the same path, whether going evaporation Possible short-

Temperature and mixing of Evaporation, mixing term collapse up or9781284457162_CH13_PASS02.indd down 379 axis of the syncline are younger than strata farther away. The axis of meltwater 25/10/16 3:36 pm an anticline or syncline might remain parallel to the Earth’s surface, Rising sea level over land o r it m ig h t p lu n g e b e n e a t h t h e s u r fa c e a t a n a n g le . Plate Tectonics9781284457162_CH07_PASS02.indd 178 Cold Chapter 2 Ocean Circulation unable to re-establish for much longer time 40 LAST GLACIAL MAX Greatly increased meltwater input Circulation collapses with Warm increased meltwater Limestone Ocean input at the

circulation Time end of a One way unable to glacial interval 9781284457162_CH02_PASS04.indd 40 Land re-establish for much longer time Long-term

Shale Temperature collapse

Sandstone Ocean Circulation State Locality Z One way Cold (a) Data from: Paillard, D. 2001. Glacial hiccups. Nature, 409, 148 (Figure 1A). Locality Y (b) Locality X In contrast to the elevator, Miscorrelation escalators only move in one assuming direction. Princeton University Press. Figure 14.1 (p. 151).

Limestone (a) Data from: Alley, R. B. 2000. The Two-Mile Time Machine: Ice Cores, Abrupt Climate Change, and Our Future. Princeton, NJ: Rock = Time Climate modes and hysteresis loops. (a) How a hysteresis loop works. Any time you are on the elevator, you can reverse FIGURE 16.19 Shale direction pretty much at any point and go back the way you came. However, if you take the escalator, you can only return to your initial position by a new path, as shown. (b) Hysteresis loop for climate (temperature) stability as a function of NADW production in the North . Figure 3.12 (p. 48). Atlantic Ocean. The modern North Atlantic has two basic climate modes. Top (present day): If meltwater input exceeds a threshold value, ocean circulation jumps (dashed line pointing down) from the upper warm mode (unperturbed present-day state) to the lower, As sea level rises, the three Sandstone (a) As sea level rises, the three colder mode (solid blue line), where NADW slows. Climate can only return (dashed line pointing up) to the warm mode (upper line) when M i s c o r r e l a t i o n s meltwater has mixed or evaporated suiciently. Note that both of these more moderate warm and cold modes could occur under modern Land (b) M i s c o r r e l a t i o n s (b) Data from: Wicander, R., and Monroe, J. S. 2000. Historical Geology: Evolution of Earth and Life Through Time, 3rd ed. Paci c Grove, CA: Brooks/Cole conditions. Bottom (last glacial maximum): Like the escalators in part A, it takes a much larger disturbance like a large influx of meltwater to shut down modern NADW formation for longer periods of time. This is presumably what happened during glacial intervals when much greater volumes of meltwater would have been released.

F I G U R E 6 . 9 The di erence between facies and formations, illustrating that rock and time are not the same. Figure 16.1). So, too, do the Younger Dryas and Heinrich formations represented by sandstone, shale, and limestone, move landward. All three environments exist through time, but the ages of events. each of the types of rocks, which are recognized as formations, di ers over the area in which the rocks are exposed. . After We might be confronted with such a climatic thresh- result if rock and time are considered equal (arrows). The red and orange dots represent the extinctions of trilobites thatbiostratigraphy are used instead to old in the near future. Recent data suggest that freshen- produce more accurate time lines for correlation (see section “6.5.3 Biostratigraphy”The for use further of fossils discussion). to study theNote stratigraphic how the ages relation- of the rocks But, if a large freshwater input occurs, such as that which ing of the North Atlantic has occurred over about the last are not the same between the localities, even within the same formation. ships of sedimentary rocks is called apparently happened during the Younger Dryas, climate 40 years of the 20th century in the vicinity of Greenland and formations have been identified and mapped, they can be might shift to a new mode for the foreseeable future. In the Iceland. If the glaciers melt sufficiently, NADW production correlated using their enclosed fossils. For example, the time case of large freshwater inputs to the North Atlantic, sum- might suddenly shut down, which could send the northern the field at the scale of a few outcrops at the base of the lines in the example of the Grand Canyon were established mers in Ireland would resemble those of Spitsbergen (north- hemisphere into a deep freeze after a prolonged interval of Grand Canyon. using the extinctions of fossils called trilobites, which are dis- ern Greenland) and winters in London those of Siberia! warming due to fossil fuel combustion. xviii The Student Experience Last Appearance In the future such meltwater inputs could occur in tantly related to insects, crabs, lobsters, shrimp, and spiders.). CONCEPT AND REASONING CHECKS The easiest way to conduct biostratigraphyFigure is to use 6.10 the response to the combustion of fossil fuels. Indeed, humans First Appearance Datums (FADs) and might be pushing Earth’s climate closer and closer toward a CONCEPT AND REASONING CHECK threshold beyond which climate will rapidly shift to a new W h y d o e s n ’ t r o c k n o r m a l l y e q u a l t i m e ? Datums (LADs) of different fossil species ( 1. © Jones & Bartlett Learning, LLC, an Ascend Learning Company.mode NOT that might FOR or SALEmight not OR bode DISTRIBUTION well for us. Based on 2. Diagram the shi of facies in a transgressing and regressing Usually, the FAD of a species represents the first evolution- the hysteresis loop, it is conceivable that, given the input 1. What are the climatic implications of a hysteresis loop? seaway. Then, indicate the formations. ary appearance of the species, and the LAD its extinction. into Earth’s atmosphere from fossil fuel combustion, 519 The use of FADs and LADs was developed over the past few of CO2 might accumulate in Earth’s atmosphere with little or decades by the Deep Sea Drilling Program; its successor, CO2 9781284457162_FMxx_00i_xxii.indd 18 Climatic Modes and Climatic07/11/16 Irreversibility 1:47 pm the Ocean Drilling Program (now superseded by the Inte- no effect until a threshold is crossed and climate suddenly 16.6 6.5.3 Biostratigraphy suggest has happened in the past (see grated Ocean Drilling Program), and petroleum companies. shifts into an entirely2 new mode. This is certainly what ice 24/10/16 1:22 pm Very often, though, lithocorrelation works quite well. In These groups needed methods that could be used in rapid core records of CO H fact, geologists use it all the time to correlate well-logs biostratigraphic correlation of sediments in deep-sea cores within relatively small areas. However, rock can only be con- and oil wells. In fact, of all the types of biostratigraphic datums, fidently equated with time over relatively short distances. If FADs and LADs are probably the most easily and rapidly we are to correlate successfully over longer distances and avoid making erroneous reconstructions of Earth history, we must use fossils because the succession of fossils can be 25/10/16 3:54 pm equated with time. 9781284457162_CH16_PASS02.indd 519 Geologic Time and Stratigraphy Chapter 6 156

9781284457162_CH06_PASS03.indd 156 TEACHING TOOLS

Volcanic island arc

A variety of Teaching Tools are available for qualified instruc- nn Lecture Outlines in PowerPoint format—The tors to assist with preparing for and teaching their courses. Lecture Outlines in PowerPoint format provide lec- These resources are accessible via digital download and mul- ture notes and images for each chapter of Earth’s tiple other formats: Evolving Systems: The History of Planet Earth, Sec- ond Edition. Instructors with Microsoft Power-

Morrison Formation Point can customize the outlines, art, and order of Retreating Sundance Sea Figure 23.16A (p. 610). Folding and thrusting presentation and add their own material. Franciscan Group Data from: Monroe, J. S., and Wicander, R. 1997. The Changing Earth: Exploring Geology and Evolution, 2nd ed. Belmont, CA: West/Wadsworth. (a)

379 (b) Orogeny, Sea Level, and Sedimentation Seaways, tectonics, and sedimentation in the interior of western13.4 North America during the Jurassic. (a) The Morrison FIGURE 13.17 24/10/16 11:42 am Formation, which is molasse shed from the west that filled the Sundance Sea. (b) Exposure of the Morrison Formation. PRESENT DAY Relatively weak meltwater input Ocean Warm circulation may temporarily slow or stop if Circulation there is enough eventually meltwater input returns to Elevator travels along normal by same path, whether going evaporation Possible short-

Temperature and mixing of Evaporation, mixing term collapse up or9781284457162_CH13_PASS02.indd down 379 meltwater

Cold Ocean Circulation unable to re-establish for much longer time

LAST GLACIAL MAX Greatly increased meltwater input Circulation collapses with Warm increased meltwater Ocean input at the circulation end of a One way unable to glacial interval re-establish for much

longer time Long-term Temperature collapse nn Key Image Review—The Ocean Circulation State One way Cold Data from: Paillard, D. 2001. Glacial hiccups. Nature, 409, 148 (Figure 1A). Key Image Review provides (b) In contrast to the elevator, the illustrations, photo- escalators only move in one direction. Princeton University Press. Figure 14.1 (p. 151). graphs, and tables to which (a) Data from: Alley, R. B. 2000. The Two-Mile Time Machine: Ice Cores, Abrupt Climate Change, and Our Future. Princeton, NJ: Climate modes and hysteresis loops. (a) How a hysteresis loop works. Any time you are on the elevator, you can reverse Jones & Bartlett Learning FIGURE 16.19 direction pretty much at any point and go back the way you came. However, if you take the escalator, you can only return to your initial holds the copyright or has position by a new path, as shown. (b) Hysteresis loop for climate (temperature) stability as a function of NADW production in the North Atlantic Ocean. The modern North Atlantic has two basic climate modes. Top (present day): If meltwater input exceeds a threshold permission to reprint digi- value, ocean circulation jumps (dashed line pointing down) from the upper warm mode (unperturbed present-day state) to the lower, colder mode (solid blue line), where NADW slows. Climate can only return (dashed line pointing up) to the warm mode (upper line) when tally. These images are not meltwater has mixed or evaporated suiciently. Note that both of these more moderate warm and cold modes could occur under modern conditions. Bottom (last glacial maximum): Like the escalators in part A, it takes a much larger disturbance like a large influx of meltwater to shut down modern NADW formation for longer periods of time. This is presumably what happened during glacial intervals when much for sale or distribution but greater volumes of meltwater would have been released. may be used to enhance Figure 16.1). So, too, do the Younger Dryas and Heinrich events. your existing slides, tests, We might be confronted with such a climatic threshold in the near future. Recent data suggest that freshen- and quizzes or other class- But, if a large freshwater input occurs, such as that which ing of the North Atlantic has occurred over about the last apparently happened during the Younger Dryas, climate 40 years of the 20th century in the vicinity of Greenland and room material. might shift to a new mode for the foreseeable future. In the Iceland. If the glaciers melt sufficiently, NADW production case of large freshwater inputs to the North Atlantic, sum- might suddenly shut down, which could send the northern mers in Ireland would resemble those of Spitsbergen (north- hemisphere into a deep freeze after a prolonged interval of ern Greenland) and winters in London those of Siberia! warming due to fossil fuel combustion. In the future such meltwater inputs could occur in xix response to the combustion of fossil fuels. Indeed, humans might be pushing Earth’s climate closer and closer toward a CONCEPT AND REASONING CHECK threshold beyond which climate will rapidly shift to a new mode that might or might not bode well for us. Based on © Jones & Bartlett Learning, LLC, an Ascend Learning Company. NOT FOR SALE OR DISTRIBUTION the hysteresis loop, it is conceivable that, given the input 1. What are the climatic implications of a hysteresis loop? into Earth’s atmosphere from fossil fuel combustion, 519 of CO2 CO2 might accumulate in Earth’s atmosphere with little or Climatic Modes and Climatic Irreversibility 9781284457162_FMxx_00i_xxii.indd 19 07/11/16 1:47 pm no effect until a threshold is crossed and climate suddenly 16.6 shifts into an entirely2 suggestnew mode. has happenedThis is certainly in the whatpast (seeice 24/10/16 1:22 pm core records of CO

9781284457162_CH16_PASS02.indd 519 nn Test Bank Material—The author has provided 500+ the Review Questions and Food for Thought exercises at multiple-choice questions, including true-false, match- the end of each chapter and the Concept and Reasoning ing, and identications. Each chapter has approximately Checks embedded throughout. These could be used in 30 to 40 questions. The author of this text has used smaller classes as writing assignments. Students could some—but certainly not all—of these questions in his be assigned the questions ahead of time or given a list to introductory course. Many questions ask for basic fac- choose from. These questions are available as an instruc- tual information, others are intended to make students tor download. “think about it.” In some cases, essentially the same nn Instructor’s Manual—An Instructor’s Manual contain- questions are worded differently. Alternative wordings ing an instructor’s overview, instructional aids, answers and answers are suggested for some questions. Some to Review and Food for Thought questions, and sugges- questions refer to specic gures in the text. Instruc- tions for homework or in-class projects and assignments tors are welcome to modify the questions as they see t. is available for each chapter. Short and long essay questions can be developed from

xx Teaching Tools

9781284457162_FMxx_00i_xxii.indd 20 07/11/16 1:47 pm ACKNOWLEDGMENTS

Earth’s Evolving Systems had its beginnings in my book One I express my gratitude to the reviewers of the first edi- Long Experiment: Scale and Process in Earth History (1998, tion, whose feedback helped to shape the text in many ways: Columbia University Press), the reviews of which were Rick Batt, Buffalo State College encouraging. Alan Benimoff, College of Staten Island–CUNY Many individuals contributed to the publication of this Walter S. Borowski, Eastern Kentucky University work. I would like to thank Stan Wakefield for putting me Robert Cicerone, Bridgewater State College in touch with Jones & Bartlett Learning regarding the man- Joshua C. Galster, Montclair State University uscript. I would also like to thank Editor Audrey Schwinn William Garcia, University of North Carolina at Charlotte who guided the text through its preproduction phase; Rights Tamie J. Jovanelly, Berry College and Media Specialist Jamey O’Quinn; and Media Develop- Matthew G. Powell, Juniata College ment Editor Shannon Sheehan. I would also like to thank Steven H. Schimmrich, SUNY Ulster County Senior Production Editor, Nancy Hitchcock, whose careful Community College eyes for detail have much improved the book and kept it on Greg W. Scott, Lamar State College–Orange track for publication. A number of recent undergraduate geology majors at Comments from the following reviewers helped to shape this the University of Delaware have contributed to this book second edition: with their enthusiasm during the courses I have taught, Alan I. Benimoff, College of Staten Island especially Emily Cahoon, Mary Cassella, Steve Cinderella, Harry Dowsett, U.S. Geological Survey Lauren Cook, Laura Dodd, Kevin Gielarowski, Josh Hum- Antony N. Giles, Nicholls State University berston, Deon Knights, Kelsey Lanan, Sherri Legg, Amanda Danny Glenn, Wharton Junior College Lusas, Briana Lyons, Suzie McCormick, Livia Montone, Warren D. Huff, University of Cincinnati Steve Mulvry, Sharon Nebbia, Marc Roy, Nick Spalt, Justin Takehito Ikejiri, University of Alabama Walker, Jessie Wenke, Dave Wessell, and Erika Young. So, Arthur C. Lee, Roane State Community College too, have many students in my introductory course. I hope Margaret Karen Menge, Delgado Community College their enthusiasm validates my approach with the readers. Jill Mignery, Miami University Jean Self-Trail read portions of Chapter 14. I also thank my Donald Neal, East Carolina University running buddies for many years of physical and mental exer- Cynthia L. Parish, Lamar University tion: Al, Dick, and Sandy. Carrie E. Schweitzer, Kent State University at Stark My sincere thanks to Drs. Karen Rosenberg and Thomas David Richard Schwimmer, Columbus State University Rocek of the Department of Anthropology at the University of Delaware for their review of the section on human evolu- Finally, I thank my wife, Carol, for her encouragement tion in Chapter 15; any errors are, however, mine. throughout the writing and production of this book. Watch- Jones & Bartlett Learning would also like to thank and ing our daughter, Dana, grow up has perhaps contributed acknowledge Dr. Amanda Julson of Blinn College for her more to my teaching and to this book than either she or I work on revising the Lecture Outlines in PowerPoint for- will ever know or understand. mat and the Web Links, and for creating the Instructor’s Manual for this edition. In addition, we sincerely appreciate Ronald Martin the assistance of Professor Ann Harris of Eastern Kentucky Newark, Delaware University and Dr. A. M. Hunt of University of Cincinnati in creating the online assessment questions that accompany this edition.

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9781284457162_FMxx_00i_xxii.indd 21 07/11/16 1:47 pm ABOUT THE AUTHOR

history (upon which Earth’s Evolving Systems is based), Pale- ontology, Paleoecology, Sedimentology, and Stratigraphy, and Advanced (Sequence) Stratigraphy , among others and he has been nominated several times for the university-wide Best Teacher Award. His research interests include the taphonomy (preservation) and biostratigraphy of microfossil assemblages and, most recently, the role of phytoplankton evolution in the diversification of the marine biosphere. He is the author or co-author of more than 60 papers; in addition to Earth’s Evolv- ing Systems, he has also authored One Long Experiment: Scale and Process in Earth History (Columbia University Press) and Taphonomy: A Process Approach (Cambridge University Press) and edited Environmental Micropaleontology: The Application of Microfossils to Environmental Geology (Kluwer/Plenum Press). He received the Best Paper Award in 1996 from the jour- Ron Martin is Professor of Geological Sciences at the Univer- nal Palaios for “Secular Increase in Nutrient Levels Through sity of Delaware. He grew up in southwestern Ohio, where the Phanerozoic: Implications for Productivity, Biomass, and world famous assemblages of Late Ordovician fossils drew his Diversity of the Marine Biosphere”; his work was also featured attention to paleontology. He received a B.S. degree in Geol- as the cover article in the June (2013) issue of Scientific Amer- ogy and Paleontology from Bowling Green State University ican: “Tiny Engines of Evolution,” which was translated into (Ohio), M.S. in Geology from the University of Florida, and French, German, Spanish, and Japanese sister publications. Ph.D. in Zoology from the University of California at Berke- He is past president of the North American Micropaleontol- ley. He worked as an operations micropaleontologist and ogy Section of the Society of Sedimentary Geology, former biostratigrapher for Unocal in Houston (Texas) from 1981– Editor of the Journal of Foraminiferal Research, and Associate 1985 before coming to the University of Delaware. He has Editor of Palaios. He was Visiting Professor at the Université taught introductory courses in physical geology and Earth de Lille (France) in 2014.

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