University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2018-01-09 Ontogeny of Population-Specific Phenotypic Variation in the Threespine Stickleback Pistore, Alexandra Pistore, A. E. (2018). Ontogeny of Population-Specific Phenotypic Variation in the Threespine Stickleback (Unpublished masters thesis). University of Calgary, Calgary, AB. http://hdl.handle.net/1880/106305 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY Ontogeny of Population-Specific Phenotypic Variation in the Threespine Stickleback by Alexandra Pistore A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE GRADUATE PROGRAM IN MEDICAL SCIENCE CALGARY, ALBERTA JANUARY, 2018 © Alexandra Pistore 2018 Abstract The Threespine Stickleback (Gasterosteus aculeatus) is a fish commonly used for the study of adaptive radiation, phenotypic plasticity, parallel evolution, and epigenetic mechanisms. Information regarding stickleback development, however, is largely missing from the literature. Using 2D and 3D analysis, I characterized skeletal and soft tissue development in four phenotypically diverse populations of stickleback, three marine and one freshwater. Fish as early as 5 days post fertilization can be distinguished by population, and by 90 days post fertilization, stickleback juveniles have developed a nearly complete skeleton and have attained their population-specific phenotype. This research gives some of the first indications of phenotype development in the Threespine Stickleback, and suggests that juvenile stickleback may be a target of selection in the fish’s expansion into new habitats. Keywords: Threespine stickleback, Gasterosteus aculeatus, phenotype, juvenile, embryo, development, ontogeny, skeleton, epigenetics ii Acknowledgements I absolutely could not have done this work without an army of people at my back. Thank you to my lab mates/soul sisters Tegan Barry, Chelsey Zurowski, Emma Carroll, and Riley Waytes for making me laugh, for reminding me that there’s always time for crafts, for the countless tea and lunch and hiking dates, and for suffering through early morning gym sessions with me. Hashtags will never be the same. Thank you especially to Tegan, who always had time to answer my questions, and who drove me all over Western Canada to catch fish. Minivans seem way cooler now. Thank you to my lab mates Sarah Anderson, Sara Smith, Jori Harrison, Matthew Morris, Ella Bowles, Stevi Vanderzwan, Brandon Allen, Hayley Britz, Rebecca Green, Chris Percival, Jacinda Larson, and Francis Smith for all of the hard work that they did before me, for troubleshooting with me, and for offering insight. This thesis was built upon the shoulders of giants. Thank you, too, to Dr. Benedikt Hallgrimsson for sharing his lab with us. Thank you to my committee of the most powerfully intelligent yet enormously supportive men – Doctors Sean Rogers, John Bertram, and Steve Vamosi – for the meetings, revisions, emails, and time taken out of Christmas holidays. This process has never been unduly stressful thanks to your incredible support. Thank you to my family and friends for ignoring me when I needed to be ignored, and for asking me about my research even though it held, for them, the interest factor of a dusty countertop. And finally, thank you to my supervisor and science wizard Heather Jamniczky. The English language (and all of the others, I suspect, but cannot confirm) do not contain the words necessary to thank you for all that you have done. Team fish! iii Table of Contents Abstract .............................................................................................................................. ii Acknowledgements .......................................................................................................... iii Table of Contents ............................................................................................................. iv List of Tables .................................................................................................................... vi List of Figures and Illustrations .................................................................................... vii List of Symbols, Abbreviations and Nomenclature ......................................................xv Epigraph ......................................................................................................................... xvi Chapter 1 – Introduction ..................................................................................................1 1.1 General Introduction .............................................................................................1 1.2 Development and Evolution ....................................................................................1 1.3 Threespine Stickleback ............................................................................................5 1.4 Thesis Outline ...........................................................................................................8 Chapter 2 - Methods ........................................................................................................10 2.1 Fish Collection ........................................................................................................10 2.2 Fish Care .................................................................................................................11 2.3 Crossing ..................................................................................................................12 2.4 Raising Juveniles ....................................................................................................13 2.5 Sampling .................................................................................................................15 2.6 Genetics ...................................................................................................................15 2.7 Photography and 2D Imaging ...............................................................................16 2.8 2D Landmarking and Statistical Analysis ...........................................................16 2.9 MicroCT Scanning and 3D Imaging ....................................................................18 2.10 3D Landmarking ..................................................................................................19 2.11 2D and 3D Morphometrics ..................................................................................20 Chapter 3 - Results...........................................................................................................22 3.1 2D Morphometrics .................................................................................................22 3.1.1 Consistency of Landmarking ........................................................................22 3.1.2 Dorsal Component by Population ................................................................22 3.1.3 Dorsal Component by Age ............................................................................24 3.1.4 Lateral Component by Age ...........................................................................28 3.1.5 Dorsal Component Pooled ............................................................................31 3.1.6 Lateral Component Pooled ...........................................................................33 3.2 3D Morphometrics .................................................................................................35 3.2.1 Consistency of Landmarking ........................................................................35 3.2.2 By Population .................................................................................................35 3.2.3 By Age .............................................................................................................38 3.2.4 Pooled ..............................................................................................................40 Chapter 4 - Discussion .....................................................................................................43 4.1 Population-Specific Variation is Present in 2D Explorations of Threespine Stickleback ............................................................................................................44 iv 4.2 Population-Specific Variation is Present in 3D Explorations of Threespine Stickleback ............................................................................................................45 4.3 Population-Specific Phenotypes Appear Early ...................................................47 4.4 Sexual Dimorphism is not Consistent Across Populations.................................47 4.5 Implications of Lab Rearing Juveniles on Phenotype ........................................50 Chapter 5 - Limitations ...................................................................................................52 Chapter 6 - Future Directions and Significance............................................................55 Tables ................................................................................................................................58