Interpreting Paleontology, Evolving Ecosystems, and Climate Change in the Cenozoic Fossil Parks
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AN ABSTRACT OF THE THESIS OF Jason P. Kenworthy for the degree of Master of Science in Geology presented on April 8, 2010. Title: Changes in Landscape, Climate, and Life During the Age of Mammals: Interpreting Paleontology, Evolving Ecosystems, and Climate Change in the Cenozoic Fossil Parks Abstract approved: ___________________________________________________________________________________ Robert J. Lillie This thesis develops a manual for interpreters at six National Park Service areas established to preserve and interpret fossils of the Cenozoic Era: Fossil Butte National Monument (Wyoming), John Day Fossil Beds National Monument (Oregon), Badlands National Park (South Dakota), Florissant Fossil Beds National Monument (Colorado), Agate Fossil Beds National Monument (Nebraska), and Hagerman Fossil Beds National Monument (Idaho). The manual will help interpreters place their park’s story into the context of three components of paleoecosystems preserved in each park: changes in geologic landscapes, global climate, and the evolution of mammals. It also provides context for interpreting modern climate change. The colorful landscapes of the Cenozoic fossil parks preserve evidence of changing landscapes, climates, and life as well as clues about change affecting our future. Because the six parks are nationally and globally significant paleontological sites, they also offer interpretive opportunities to connect visitors to the science of paleontology. The manual is written for interpreters with a variety of geology, other science and humanities backgrounds. The first three chapters provide a basic foundation of paleontological knowledge and interpretive resources applicable to all of the parks. Chapter 1 is an introduction to the scope and significance of the fossils and paleoecosystems preserved in each of the Cenozoic fossil parks. Chapter 2 outlines NPS interpretive theory and offers practical information for developing paleontology interpretation and interpreting long- term paleoecosystem evolution. Chapter 3 provides geologic content and interpretive methods for answering three common questions visitors ask: How old are these fossils? What is a fossil? and Were all these fossils found here? Interpretive responses to these questions allow visitors to connect with the Cenozoic Era, fossilization processes, and the profound sense of place afforded by the fossil parks. Chapters 4, 5, and 6 summarize how the major components of ecosystems changed between the extinction of dinosaurs 65 million years ago and the beginning of the Pleistocene “ice ages” 2.6 million years ago. Chapter 4 details the active geologic processes—mountain building and volcanic activity—of the American West during this time period and how these processes helped form and preserve the paleoecosystems of the parks. Chapter 5 places the parks’ paleoecosystems in chronological order and relates them to the global climate transition from the “greenhouse” world (nearly-tropical forests and lakes at Fossil Butte NM, John Day Fossil Beds NM, Badlands NP, and Florissant Fossil Beds NM) of 65 to 34 million years ago, to the “icehouse” world (cooler and drier woodlands, savannahs, and grasslands at John Day Fossil Beds NM, Badlands NP, Agate Fossil Beds NM, and Hagerman Fossil Beds NM) beginning 34 million years ago and continuing today. Chapter 6 traces the evolution of the horse during this time of global change from a four-toed, dog-sized browser to a hoofed, zebra-sized grazer on the grasslands of the American West. Chapter 7 describes the “ice ages” that followed the stories of the Cenozoic fossil parks. It also places the global climatic and ecosystem changes told by the Cenozoic fossil parks in the context of modern, rapid, anthropogenic climate changes. Each chapter includes “Digging Deeper” boxes that provide more detailed geologic content, or interpretive suggestions. © Copyright by Jason P. Kenworthy April 8, 2010 All Rights Reserved Changing Landscape, Climate, and Life During the Age of Mammals: Interpreting Paleontology, Evolving Ecosystems, and Climate Change in the Cenozoic Fossil Parks by Jason P. Kenworthy A THESIS submitted to Oregon State University in partial fulfillment of the requirements for the degree of Master of Science Presented April 8, 2010 Commencement June 2010 Master of Science thesis of Jason P. Kenworthy presented on April 8, 2010. APPROVED: _______________________________________________________________ Major Professor, representing Geology _______________________________________________________________ Chair of the Department of Geosciences _______________________________________________________________ Dean of the Graduate School I understand that my thesis will become part of the permanent collection of Oregon State University libraries. My signature below authorizes release of my thesis to any reader upon request. ___________________________________________________________________________________ Jason P. Kenworthy, Author ACKNOWLEDGEMENTS This thesis was made possible through the contributions of numerous people and the funding and support of Oregon State University and the National Park Service (NPS). My advisor, Bob Lillie, was instrumental in the completion of this project. His passion for geology interpretation in the NPS is inspiring and his insightful, thoughtful, and thorough editing greatly improved this document. Thanks to my other committee members for their support: Ted Fremd (John Day Fossil Beds NM, recently retired), Ed Brook (OSU Geosciences), and Marta Torres (OSU College of Atmospheric and Oceanic Sciences). Thanks to all the interpreters, paleontologists, and staff at each park. Their enthusiasm, hospitality, and knowledge were invaluable! Special thanks to: Blanca Stransky, Sam Fisher, Betty Mack, Lil Mansfield, Mark Hertig, and Maribeth Kambitsch (Agate Fossil Beds NM); Julie Johndreau, Rachel Benton, Brad Fishback, Aaron Kaye, and the Big Pig Dig field crew (Badlands NP); Jeff Wolin and Herb Meyer (Florissant Fossil Beds NM); Phil Gensler, Annette Rousseau, Mary Carpenter, Patrick Taylor, Dylan Jones, Casey McKinney, and Bob Lorkowski (Hagerman Fossil Beds NM); John Fiedor, Lia Vella, Sara Herve, Matt Smith, Chris Schierup, and Michelle Ordway (John Day Fossil Beds NM). The logistics of working at five parks over two summers was made considerably less complicated by the administrative staffs of the parks and the NPS Geologic Resources Division (GRD). The parks provided funding and housing during the summers of 2007 and 2008. The GRD provided additional funding and travel support. Thanks to everyone at GRD for their support as I juggled my job and my thesis. An OSU Teaching Assistantship provided funding from 2007 through 2008. Allyson Mathis (Grand Canyon NP) offered comments on an early version of Chapters 2 and 3. Greg Retallack (University of Oregon) and Ron Blakey (Northern Arizona University) made their paleosol and paleogeography reconstructions available for use. Thanks to the entire staff of Fossil Butte NM for welcoming me during my first stint with the NPS more than nine years ago and for their continued support as the thesis came together: Arvid Aase, Marcia Fagnant, John Collins, Clay Kyte, Dave McGinnis, Anne Bluemel, and Liz Parker. The encouragement and enthusiasm of Vincent Santucci (George Washington Memorial Parkway) ignited my passion for paleontology and the Green and Gray. Thanks to all the grad students that shared kickball, Squirrels, Bombs, and the hallways and classrooms of Wilkinson, especially Trench, Wiley, Chris and Danielle, Chris and Cece, Ashley, Abi, Erin, Wendy, Mark, Alison, Paris, Eleanor, Jeff and Jeff. Mom, Dad, Ryan, and the Maryland gang—thanks for your support and encouragement. And finally my dearest appreciation to my wife Erin. You’ve been through it all by my side…I’m enjoying our journey and looking forward to our next adventure. Harumpfivle! TABLE OF CONTENTS Page INTRODUCTION ..................................................................................................................................... 2 Chapter 1 There are no dinosaurs here: The Cenozoic fossil parks tell the stories of the Age of Mammals. .................................................................................................................................................. 5 Fossil Butte National Monument, Wyoming ........................................................................................ 6 John Day Fossil Beds National Monument, Oregon ............................................................................. 7 Badlands National Park, South Dakota ................................................................................................. 8 Florissant Fossil Beds National Monument, Colorado ....................................................................... 10 Agate Fossil Beds National Monument, Nebraska ............................................................................. 10 Hagerman Fossil Beds National Monument, Idaho ............................................................................ 11 Chapter 2 Interpretation connects visitors to the Cenozoic fossil parks ................................................. 31 Tilden’s Six Principles of Interpretation ............................................................................................. 31 The Interpretive Equation ................................................................................................................... 32 Knowledge of the Resource: Foundation