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FEEDING MORPHOLOGY AND KINEMATICS IN SURFPERCHES (EMBIOTOCIDAE: PERCIFORMES): EVOLUTIONARY AND FUNCTIONAL CONSEQUENCES A Thesis Presented to the Faculty of California State University, Stanislaus and Moss Landing Marine Laboratories In Partial Fulfillment of the Requirements for the Degree of Master of Science in Marine Science By Kimberly Quaranta June 2011 i ACKNOWLEDGEMENTS This work would not have been made possible without the acceptance, battle, forgiveness, and mentorship of Dr. Lara Ferry. She helped create a love for functional morphology and fishes, and gave me a chance when needed most. To Dr. Greg Cailliet, who in his own right is a gift to life learning, I am truly grateful to have worked on this thesis with him. It has been an academic and emotional adventure that has left me a better person due to his influence and guidance. Dr. Peter Wainwright was instrumental in providing valuable comments and time spent pouring over my dataset. This thesis or dream of becoming a marine scientist would also not have been possible without the amazing support of Dr. Pam Roe. Gratitude for her efforts in processing paperwork, valuable edits and comments, and overall passion and enthusiasm for science will never fully be adequately expressed in words. To all my friends and cohorts at MLML for countless hours working late nights, playing foosball, having wonderful dinner parties, scuba diving, helping each other with our research, and just being there for one another, I thank you. To all the MLML staff and faculty, you truly made this experience special and unforgettable. Special thanks to Kenneth Coale, who has been a great leader, friend and teacher. Lastly, I would like to thank my family. My mother, Carol and father, Joseph for giving me life, and everything I could have ever wanted from it. iii TABLE OF CONTENTS PAGE Acknowledgments….................................................................................................... iii List of Tables .................................................................................................................v List of Figures............................................................................................................. vi Chapter I Abstract..............................................................................................................2 Introduction....................................................................................................... 4 Methods............................................................................................................. 7 Results............................................................................................................. 11 Discussion....................................................................................................... 14 References....................................................................................................... 25 Appendix I: Morphological and mechanical characteristics of the body and feeding apparatus in 10 species of embiotocids............................. 56 Chapter II Abstract........................................................................................................... 59 Introduction..................................................................................................... 61 Methods........................................................................................................... 64 Results..............................................................................................................66 Discussion....................................................................................................... 67 References....................................................................................................... 73 iv LIST OF TABLES TABLE PAGE Chapter I 1. Location and method of collection for surfperch specimens................................. 33 2. Principle components analysis on 10 morphological variables related to feeding in 10 embiotocid species........................................................... 34 3. One way Analysis of Variance (ANOVA) for each PCA explaining 10% or more of the total variance...........................................................................35 TABLE PAGE Chapter II 1. Measurements made to produce kinematic variables (Westneat, 1990).................82 2. Mean peak maximums and standard error for all five kinematic variables measured during high speed video ..........................................................83 3. Mean time to peak maximums and standard error for all five kinematic variables measured during high speed video ......................................................... 84 4. Results of t values for differences amongst Embiotoca jacksoni and Embiotoca lateralis for each kinematic variable ............................................ 85 v LIST OF FIGURES FIGURE PAGE Chapter I 1. Head length, standard length, and total length measurements made ................... 37 2. Diagram showing depression of the lower jaw resulting in protrusion of the upper jaws...................................................................................................38 3. Illustration of vertical and horizontal gape measurement.................................... 39 4. Placement of the adductor mandibular and sternohyoideus ................................ 40 5. Placement of the levator posterior muscle and lower pharyngeal jaw plate in embiotocids .......................................................................................41 6. Lower jaw levers for calculating mechanical advantage ......................................42 7. Measurements of the four links used in calculating the kinematic transmission coefficient ........................................................................................43 8. Separation of embiotocid species along PC 1 (26.8 %)........................................44 9. Boxplot of the adductor mandibulae mass............................................................46 10. Boxplot of vertical gape........................................................................................47 11. Boxplot of the sternohyoideus muscle mass.........................................................48 12. Boxplot of jaw opening mechanical advantage ....................................................49 13. Boxplot of the kinematic transmission coefficient (KT) for the oral four-bar linkage mechanism ..........................................................................50 14. Separation of embiotocid species along principle component axis 3 (17.8 %)..............................................................................................................51 15. Boxplot of the variable, levator posterior muscle (A), which loaded highest on principle component 3 and the lower pharyngeal jaw mass that loaded next highest .......................................................................................52 vi 16. Separation of embiotocid species along PC 4 (12 %)...........................................53 17. Box plot of the highest loading variable, jaw closing mechanical advantage, on principle component axis four .......................................................54 FIGURE PAGE Chapter II 1. Landmarks associated with measurements made for all kinematic variables, from Westneat, 1990.............................................................................................. 87 2. Still frames from high speed video showing prey capture and expression of kinematic variables.......................................................................... 88 3. Strike patterns for Embiotoca jacksoni and Embiotoca lateralis........................... 89 vii CHAPTER ONE ANALYSIS OF THE TROPHIC MORPHOLOGY AND MECHANICS IN 10 SPECIES OF SURFPERCHES (PERCIFORMES: EMBIOTOCIDAE) 1 ABSTRACT The surfperch family (Embiotocidae) is relatively small, having 23 species and occupying temperate water. They exhibit highly derived jaw morphology resembling that of tropical species, such as labrids, with tremendous diversity. Surfperches forage in specific, often predictable ways, and can be categorized into winnowers, pickers (nonwinnowers), and crushers. In addition, surfperches are viviparous and lack larval stages thus limiting their distribution. Therefore, it is hypothesized that their jaw morphology has led to their success in partitioning resources by means of their foraging behavior. This study used morphometrics to assess the potential diversity in jaw morphology among 10 species in this family. Measurements were made on preserved specimens, including jaw lengths and mass of muscles associated with operation of the jaw. The large set of morphometrics was analyzed using a Principal Components Analysis to determine which variables explained the most variation in surfperch jaw morphology and diversity, in addition to an Analysis of Variance (ANOVA) to determine how they differ from one another. The morphology of surfperches did not differentiate between pickers and winnowers, but morphology was able to distinguish the one species noted as a crusher (Damalichthys vacca). However, the data showed that there were significant differences among species in jaw morphology and musculature. Although there was not a direct correlation between foraging behavior and morphology, it is likely that surfperches coxist based 2 on their ability to modulate prey acquisition in their habitat. Despite the relatively low number of species within