Evolution of Body Mass in Coleoptera: Insights from Museum Specimens and DNA Barcodes
Total Page:16
File Type:pdf, Size:1020Kb
Evolution of Body Mass in Coleoptera: Insights from Museum Specimens and DNA Barcodes by Jingchan Hu A Thesis presented to The University of Guelph In partial fulfilment of requirements for the degree of Master of Science in Integrative Biology Guelph, Ontario, Canada © Jingchan Hu, December 2019 ABSTRACT Evolution of Body Mass in Coleoptera: Insights from Museum Specimens and DNA Barcodes Jingchan Hu Advisor: University of Guelph, 2019 Dr. Paul D. N. Hebert Advisory Committee Members: Dr. Sarah J. Adamowicz Dr. Jinzhong Fu This thesis investigates the evolution of body mass in Coleoptera, one of the most diverse orders of animals. By quantifying the mass of over 3,000 Canadian species using museum specimens stored at the Centre for Biodiversity Genomics, it describes fundamental yet under- investigated aspects of body mass variation in Coleoptera, such as species-size distributions and the partitioning of variation at different taxonomic levels. Using DNA barcode sequences and backbone phylogenies, it also illustrates trajectories of mass evolution, evaluating the influence of phylogenetic constraints and ecological specialization. Both lineage-wide patterns as well as phylogenetic parameters in Coleoptera appear to diverge strongly from trends noted in vertebrate groups, providing new insights into the evolution of a fundamental biological trait. As well, this thesis provides direction and methodologies for future studies to utilize museum specimens in investigations of arthropod body mass. iii ACKNOWLEDGEMENTS This research was funded by a Discovery Grant from the Natural Sciences and Engineering Research Council of Canada (NSERC) awarded to Dr. Paul Hebert. I would like to thank Dr. Paul Hebert for being my advisor for this thesis, and for his feedback and advice throughout. Paul gave me considerable autonomy and freedom to explore in this project, but also provided invaluable insight and advice at every key step. It is thanks to him that I have gained essential experiences of the research process, from planning to presentation, in completing this project. I also thank the members of my advisory committee, Dr. Sarah J. Adamowicz and Dr. Jinzhong Fu, for their advice, feedback, and encouragement over the years. As well, I am grateful to Dr. Dirk Steinke, Sujeevan Ratnasingham, and Dr. Mikko Pentinsaari, for generously sharing with me their knowledge and expertise, as well as the staff and work-study students at the Centre for Biodiversity Genomics collections unit, for helping me navigate the lab and stay organized through the data collection process. Finally, thank you to members of the Hebert Lab, the Steinke Lab, and other CBG staff who have offered me help and support throughout this project. iv TABLE OF CONTENTS Abstract ........................................................................................................................................... ii Acknowledgements ........................................................................................................................ iii Table of Contents ........................................................................................................................... iv List of Tables ................................................................................................................................ vii List of Figures .............................................................................................................................. viii List of Appendices ......................................................................................................................... ix 1 Chapter 1: Introduction ........................................................................................................... 1 1.1 Summary .......................................................................................................................... 1 1.2 Introduction: body mass variation shapes diversity in animals........................................ 1 1.3 Measures and approximations of body mass.................................................................... 2 1.3.1 Types of mass measurement ..................................................................................... 2 1.3.2 Approximations of body mass .................................................................................. 3 1.3.3 Using museum specimens to measure arthropod dry mass ...................................... 4 1.4 Ecological and evolutionary trends in body mass: ........................................................... 5 1.4.1 Body size and diversity ............................................................................................. 6 1.4.2 Cope’s rule and stasis................................................................................................ 6 1.4.3 Spatial trends ............................................................................................................. 7 1.4.4 Sexual size dimorphism and Rensch’s rule .............................................................. 8 1.4.5 Mass in an evolutionary framework ......................................................................... 8 1.4.6 Rules of body mass are often oversimplifications .................................................... 9 1.5 Trends of body mass variation are poorly understood in insects ................................... 10 1.6 Thesis chapters ............................................................................................................... 11 1.6.1 Chapter 2: Coleoptera body mass data from museum specimens ........................... 11 1.6.2 Chapter 3: Evolution of Coleoptera body mass using DNA barcodes.................... 11 1.6.3 Chapter 4: General conclusions .............................................................................. 11 2 Chapter 2: Coleoptera body mass data from museum specimens ......................................... 12 2.1 Abstract .......................................................................................................................... 12 2.2 Introduction .................................................................................................................... 12 2.3 Materials and methods ................................................................................................... 14 2.3.1 Assessment of weighing methods and protocol ...................................................... 14 v 2.3.2 Correlation between live and dry mass ................................................................... 15 2.3.3 Data collection ........................................................................................................ 16 2.4 Results ............................................................................................................................ 17 2.4.1 Data collection ........................................................................................................ 17 2.4.2 Variation in specimen mass measurements ............................................................ 17 2.4.3 Dry-mass live-mass correlations ............................................................................. 18 2.5 Discussion ...................................................................................................................... 18 2.5.1 Museum specimens are a good source of mass data ............................................... 18 2.5.2 Suggestions for future weighing protocol ............................................................... 19 2.5.3 Additional sources of error ..................................................................................... 20 2.6 Tables and figures .......................................................................................................... 22 3 Chapter 3: Evolution of Coleoptera body mass using DNA barcodes.................................. 23 3.1 Abstract .......................................................................................................................... 23 3.2 Introduction .................................................................................................................... 23 3.3 Materials and methods ................................................................................................... 26 3.3.1 BINs as a species proxy .......................................................................................... 26 3.3.2 Trait data assignment .............................................................................................. 27 3.3.3 Data exploration and initial analysis ....................................................................... 28 3.3.4 Phylogenetic trees and downstream analyses ......................................................... 29 3.3.5 Predictors of the mass of a new species .................................................................. 30 3.4 Results ............................................................................................................................ 31 3.4.1 Data distribution and variance partitioning............................................................. 31 3.4.2 Phylogenetic analyses ............................................................................................. 32 3.4.3 Predictors of unknown species mass....................................................................... 32 3.5 Discussion ...................................................................................................................... 33 3.5.1 Coleoptera mass