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Cranial Biomechanics and Feeding Performance of Sharks Daniel Robert Huber University of South Florida

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Cranial Biomechanics and Feeding Performance of Sharks Daniel Robert Huber University of South Florida University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 2006 Cranial biomechanics and feeding performance of sharks Daniel Robert Huber University of South Florida Follow this and additional works at: http://scholarcommons.usf.edu/etd Part of the American Studies Commons Scholar Commons Citation Huber, Daniel Robert, "Cranial biomechanics and feeding performance of sharks" (2006). Graduate Theses and Dissertations. http://scholarcommons.usf.edu/etd/2566 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Cranial Biomechanics and Feeding Performance of Sharks by Daniel Robert Huber A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Biology College of Arts and Sciences University of South Florida Major Professor: Philip J. Motta, Ph.D. Robert E. Hueter, Ph.D. Thomas J. Koob, Ph.D. Florence I. Thomas, Ph.D. James R. Garey, Ph.D. Date of Approval: June 2, 2006 Keywords: elasmobranch, functional morphology, aquatic prey capture, bite force, jaw suspension © Copyright 2006 , Daniel Robert Huber Dedication I dedicate this work to my parents, Mark, Geri, Joann, and Steve, for fostering a kid’s bizarre fascination with dangerous animals. Their foresight and unwavering support over the past twenty-seven years has been the foundation of the perseverance and integrity that has led to the completion of my doctorate. I am forever indebted to them, and hope that I have made them proud. Acknowledgements I would first like to acknowledge the contributions of my mentor and friend Dr. Philip J. Motta. His wisdom in all things shark and otherwise has been a guiding force in my life over the past six years and I cannot imagine having found a more insightful and cheerful person to call “boss”. Secondly, I would like to acknowledge Christina Weggelaar, whose confidence in and patience with me have been crucial to my sanity and success. Many others have contributed to the work herein, including Drs. Thomas Eason, James Garey, Robert Hueter, Thomas Koob, Adam Summers, and Florence Thomas. Years full of thought provoking conversation and brainstorming on this and other projects were provided by Angela Collins, Eric Cross, Mason Dean, Mark Driscoll, Dayv Lowry, Kyle Mara, Mike Matott, Samantha Mulvany, Justin Schaefer, Lisa Whitenack, and Alpa Wintzer. Experimental assistance was provided by Dan Conklin, Coral Gehrke, Wayne Giordano, Terry Hall, Eric Hovland, Kristen Mathews, Sean Moore, Jack Morris, Wes Pratt, Chris Schreiber, and John Tyminski. The use of facilities and specimens was provided by California State University at Long Beach, Florida Museum of Natural History, Florida Aquarium, Hokkaido University, Mote Marine Laboratory Center for Shark Research, Occidental College, SeaWorld Entertainment Parks, Texas A&M University, University of Miami, University of South Florida, and University of Washington Friday Harbor Laboratories. Funding for this project was provided by the American Elasmobranch Society, American Society of Ichthyologists and Herpetologists, Mote Marine Laboratory, PADI Project A.W.A.R.E. Foundation, Porter Family Foundation, Society for Integrative and Comparative Biology, University of South Florida Department of Biology, and University of South Florida Foundation. Table of Contents List of Tables ......................................................................................................................iv List of Figures................................................................................................................... vii Abstract.............................................................................................................................. xi Chapter One. Prey Capture Biomechanics and Feeding Performance of the Horn Shark Heterodontus francisci .........................................................................................1 Introduction..............................................................................................................3 Materials and Methods.............................................................................................6 Experimental Animals .................................................................................6 Morphological Analysis...............................................................................6 Theoretical Force Generation....................................................................10 In Situ Bite Performance Measurements....................................................12 Restrained and Stimulated Bite Force Measurements ...............................14 Statistical Analysis.....................................................................................15 Results....................................................................................................................17 Biomechanical Modeling...........................................................................17 Performance Measurements.......................................................................22 Methodological Comparison......................................................................27 Bite Forces Among Vertebrates.................................................................28 Discussion..............................................................................................................30 Functional Morphology.............................................................................30 Methodological Comparison......................................................................37 Feeding Performance .................................................................................39 Feeding Ecology........................................................................................42 Conclusions............................................................................................................44 Chapter Two. Prey Capture Biomechanics and Feeding Performance of Juvenile Lemon Sharks Negaprion brevisostris..........................................................................46 Introduction............................................................................................................48 Materials and Methods...........................................................................................52 Experimental Animals ...............................................................................52 Cranial Morphology...................................................................................52 Theoretical Biomechanical Analysis.........................................................55 Bite Performance Measurements ...............................................................58 Statistical Analysis.....................................................................................60 i Results....................................................................................................................62 Cranial Biomechanics ................................................................................62 Mechanics of Jaw Protrusion.....................................................................67 Prey Capture Performance .........................................................................68 Methodological Comparison......................................................................73 Bite Forces Among Cartilaginous Fishes ..................................................73 Discussion..............................................................................................................71 Cranial Biomechanics ................................................................................74 Mechanics and Evolution of Jaw Suspension............................................77 Prey Capture Performance .........................................................................82 Methodological Comparison......................................................................85 Conclusions............................................................................................................86 Chapter Three. Mechanical Consequences of Functional Constraint in the Feeding Mechanism of the Whitespotted Bamboo Shark Chiloscyllium plagiosum..................88 Introduction............................................................................................................90 Materials and Methods...........................................................................................95 Experimental Animals ...............................................................................95 Morphological Analysis.............................................................................95 Theoretical Force Generation....................................................................98 Bite Force Measurement..........................................................................101 Statistical Analysis...................................................................................103 Results..................................................................................................................104 Biomechanical Modeling.........................................................................104 Methodological Comparison....................................................................110
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