ON THE VALIDITY OF ARCHAEOLOGICAL SHELLFISH METRICS IN COASTAL CALIFORNIA ____________ A Thesis Presented to the Faculty of California State University, Chico ____________ In Partial Fulfillment of the Requirements for the Degree Master of Arts in Anthropology ____________ by Arran M. Bell Fall 2009 ON THE VALIDITY OF ARCHAEOLOGICAL SHELLFISH METRICS IN COASTAL CALIFORNIA A Thesis by Arran M. Bell Fall 2009 APPROVED BY THE INTERIM DEAN OF THE SCHOOL OF GRADUATE, INTERNATIONAL, AND INTERDISCIPLINARY STUDIES: _________________________________ Mark J. Morlock, Ph.D. APPROVED BY THE GRADUATE ADVISORY COMMITTEE: _________________________________ Frank E. Bayham, Ph.D., Chair _________________________________ Eric J. Bartelink, Ph.D. ACKNOWLEDGMENTS First I would like to thank Dr. Frank Bayham for working with me on this project from its inception. Without his vision and ideas this thesis would never have taken place. I would also like to thank Eric Bartelink for all the time and hard work he put into making my thesis what it is. I would especially like to thank my parents whose unconditional love and support have meant everything to me. They encouraged and sustained me through out this long process and I owe them a great deal. All of the volunteers who participated in this study were a great service to me. Their participation in this project was essential to its completion. I am very grateful for the time that they unselfishly gave to me to complete this study. I would also like to thank Greg White for allowing me to use his template and providing me with all of his original notes and background research. This information was invaluable to me and very greatly appreciated. Elena Nilsson and all of the URS team and URS Corporation have supported me through out my graduate experience. Their understanding and help have always been a great asset to me through out my time at CSU Chico. Without their support and acknowledgment this project could not have been completed. I would like to thank Melinda Button for her encouragement and friendship during the completion of this project. Her constant support, advice and help through out iii this entire experience was greatly appreciated. In addition, I would like to thank all of my graduate school cohorts from 2005 – 2007 who encouraged and supported me through out this process. Finally, I would like to thank God. Without my parent’s strong religious background and my own experiences of blessing, this project most likely would never have been completed. Skye, I love you and I miss you. As always, this is dedicated to you. iv TABLE OF CONTENTS PAGE Acknowledgments ...................................................................................................... iii List of Tables.............................................................................................................. vii List of Figures............................................................................................................. viii Abstract....................................................................................................................... x CHAPTER I. Introduction.............................................................................................. 1 Archaeofaunal Shellfish Research................................................ 4 Project Goals ................................................................................ 8 Thesis Organization...................................................................... 9 II. The Archaeology of Human Impacts ....................................................... 11 Human Behavioral Ecology ......................................................... 13 Methods Used to Identify Ecological Patterns ............................. 23 Summary....................................................................................... 29 III. An Ecological Perspective on California Mussels ................................... 30 The Natural History of the California Mussel.............................. 31 Ecology of the Coastline .............................................................. 40 Rocky Shores................................................................................ 40 Discussion..................................................................................... 47 IV. Research Design....................................................................................... 49 Sample Loci.................................................................................. 51 Phase I .......................................................................................... 59 Phase II ......................................................................................... 61 Discussion..................................................................................... 62 v CHAPTER PAGE V. Effectiveness of White Template: A Blind Study .................................... 64 Stage I: Davenport Landing Pilot Study....................................... 65 Stage II: Punta Gorda Study......................................................... 75 Summary....................................................................................... 81 VI. Morphological Variation and Size Estimation in California mussels ...... 83 Descriptive Statistics of Mussel Shells......................................... 84 Basal Angle Measurements .......................................................... 87 Incremental Height Measurements............................................... 92 Conclusions from Phase II............................................................ 100 VII. Summary and Conclusions....................................................................... 103 Summary....................................................................................... 103 Contributions to the Field of Archaeology................................... 106 References Cited......................................................................................................... 110 Appendices A. Ventral Side of the California Mussel...................................................... 118 B. Mussel Size Class Template..................................................................... 120 C. Punta Gorda Length, Height and Width Measurements........................... 122 D. Davenport Landing Length, Height and Width Measurements................ 125 E. Punta Gorda Incremental Height Measurements...................................... 130 F. Davenport Landing Incremental Height Measurements........................... 133 G. Punta Gorda Basal Angle Measurements................................................. 138 H. Davenport Landing Basal Angle Measurements...................................... 140 vi LIST OF TABLES TABLE PAGE 1. Distribution of Shellfish Fragments Size Classes from the First Blind Test, Stage I ................................................................... 67 2. Distribution of Shellfish Fragments Size Classes from the Second Blind Test, Stage I............................................................... 67 3. Distribution of Student 3 Shell Fragments When Using the Pre-Sorted Fragment Size Groups ................................................... 70 4. Distribution of Shellfish Fragments Size Classes, Stage II ...................... 76 5. Stage II Correctly Identified Shells by Volunteer .................................... 77 6. Pearson’s r Correlation Coefficient Using Results from Stage II ............ 77 7. Inter-observer Agreement Results Using Cohen’s Kappa........................ 79 8. Punta Gorda and Davenport Landing: Descriptive Statistics for Maximum Length, Height and Width with Range and Standard Deviation .......................................................................... 86 9. Number of Shells Analyzed and Their Size Ranges for Punta Gorda and Davenport Landing ........................................................ 101 vii LIST OF FIGURES FIGURE PAGE 1. California Mussel Valve Illustration, Demonstrating Location of Length and Height Measurements............................................... 2 2. Map of Punta Gorda, Humboldt County, California................................. 52 3. Map of Davenport Landing, Santa Cruz County, California.................... 55 4. California Mussel Valve Illustration, Demonstrating Location of Length, Height, and Incremental Height Measurements............. 62 5. Comparison of Student Results to Actual Shell Measurements from the First Blind Test of Stage I ................................................. 68 6. Comparison of Student 1 Results from Blind Test 1, 2 and Actual Measurements ...................................................................... 68 7. Comparison of Student Results to Actual Shell Measurements from the Second Blind Test of Stage I............................................. 71 8. Comparison of Student 2 Results from Blind Test 1, 2 and Actual Measurements ...................................................................... 72 9. Comparison of Student 3 Results from Blind Test 1, 2 and Actual Measurements ...................................................................... 74 10. Range of Student Responses for Shells Belonging to the 6 cm Size Group ....................................................................................... 80 11. Range of Student Responses for Shells Belonging to the 4 cm Size Group ....................................................................................... 80 12. Location of Length, Height and Width