EVOLUTION AND HISTORICAL BIOGEOGRAPHY OF PACIFIC COPROSMA (RUBIACEAE) A DISSERTATION SUBMITTED TO THE GRADUATE DIVISION OF THE UNIVERSITY OF HAWAI‘I AT MĀNOA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN BOTANY MAY 2014 By Jason T. Cantley Dissertation Committee: Sterling Keeley, Chairperson Vicki Funk Clifford Morden Tom Ranker Lyndon Wester © by Jason T. Cantley 2014 ii ACKNOWLEDGMENTS Without the work of the many funding sources and individuals who helped with the completion of this dissertation, it simply would not have been possible. First, I would like to thank the Botany Department at the University of Hawai‘i at Mānoa, the American Society of Plant Taxonomists, the Lamoureux Fellowship fund for graduate student research, the Graduate Student Organization at the University of Hawai‘i at Mānoa and Department of Plant Biology at Michigan State University for financial support. Extensive field work would in New Zealand not have been possible without the help of Dr. Adrienne Markey and Rewi Elliot at Otari-Wilton’s Bush in Wellington. We are very grateful to the New Zealand Department of Conservation, the Tasmanian Parks and Wildlife Service, the Dunedin City Council, Otari-Wilton’s Bush, Zealandia, and the Yellow Eyed Penguin Trust for collection permits and/or access to collection sites, and for the generous assistance of the Allen Herbarium, the Bishop Museum Herbarium, Tasmanian Herbarium, Auckland War Memorial Museum, the Western Australian Herbarium, National Tropical Botanical Garden and the Joseph Rock Herbarium for facilitating the exchange of herbarium vouchers. Fieldwork in the Hawaiian Islands would not have been possible without the help of David Lorence and Tim Flynn at NTBG, Amanda Vernon, Marian Chau, Seana Walsh, Kevin Enriques, Warren Wagner, Vicki Funk, Butch Hasse with the Moloka’i Land Trust, Bill ‘Wili’ & Audrey Garnett and Russell Kalstrom with The Nature Conservancy. Many need to be thanked for fieldwork which I was not able to fund in locations across the Pacific including Jean- Yves Meyer at the French Polynesian Delegation for Research (Délégation à la iii Recherche) for providing silica dried material of Marquesan species, Art Whistler for Samaoan species, Gerald McCormack for Cook Islands specimens, Matt Prebble and Michael Keihn for New Guinean species, Tod Steussy for samples of Juan Fernández Islands specimens and Adrienne Markey for Tasmanian and Australian Specimens. A special thanks needs to be extended to my dissertation committee members: Tom Ranker, Cliff Morden, Vicki Funk, and Lyndon Wester for all of their help with the organization and issues that arose throughout the period of research. I am overly grateful for the guidance of Dr. Sterling Keeley, my dissertation chair person. Without her help, guidance and support, I’m not sure that I would have been able to navigate the time spent as a graduate student. I also am very grateful for many insightful conversations and support from Timothy Gallaher as we were studying very similar evolutionary questions and it enabled us to often work cohesively together to learn phylogenetic software and DNA protocols. Many thanks to my botanical based friends for moral support and other wise: Marian Chau, Seana Walsh, Joanne Birch, Kim Peyton, Rachael Wade, and Jessica Neumann. There are many others who were instrumental in helping with my dissertation and I am very grateful for their help. iv ABSTRACT This dissertation investigated the evolutionary history and historical biogeography of Coprosma (Rubiaceae) across the Pacific Ocean. A brief introduction to the status of Pacific biogeography of angiosperms is discussed in Chapter 1 along with an introduction to the systematic relationships and previous research of the genus Coprosma itself. Chapter 1 ends with a description of the dissertation aims and hypotheses. The first research based chapter is Chapter 2, which aimed to elucidate the evolutionary history to the Hawaiian Islands using molecular phylogenetic analyses followed by an assessment of phylogeographic patterns within the genus. The analyses inferred two independent colonization events of Coprosma to the Hawaiian Islands: one radiation of 12 orange- fruited taxa from the Marquesas Islands or Austral Islands, and a separate independent colonization for one black-fruited species from an unclear origin. Research of Chapter 3 investigated the historical biogeography of the genus across a wide geographic distribution with many more species represented using molecular clocking techniques. The analyses inferred that Coprosma diverged from Nertera in New Zealand during the Oligocene. Subsequent diversification of New Zealand taxa was correlated temporally with tectonics of the Miocene. It was also inferred that at least 30 bird mediated long distance dispersal events, primarily within the last 10 Ma, have occurred in order to explain the extant distribution of the genus. Chapter 4 investigated the evolutionary inheritance of morphological traits, which were traced onto phylogenetic reconstructions of the genus. Resulting from this work, a key and new taxonomic description that includes six newly circumscribed subgenera was completed. Chapter 5 synthesizes the v dissertation research which has elucidated a complex novel evolutionary history of Coprosma which is one of the most widespread and species rich genera in the Pacific. vi TABLE OF CONTENTS Acknowledgements…………………………………………………………………....…iii Abstract………………………………………………………………………….…..……v List of Tables………………………………………………………………………….….x List of Figures…………………………………………………………………………....xi CHAPTER 1: INTRODUCTION…………………………………………………….…1 Patterns of Pacific biogeography…………………………………………..….…....1 Geographical distribution of Coprosma…………………………………...............6 Previous biogeographic hypotheses on Coprosma………………………...............7 Biogeography of the Hawaiian Islands and Coprosma………………………........8 Other remote Pacific localities and Coprosma…………………………………....10 The systematic relationships of Coprosma………………………………………..11 Tribe Anthospermeae……………………………………………..………....11 Subtribe Coprosminae……………………………………………….……....12 Closely related genera to Coprosma……………………………...………....13 The genus Leptostigma……………………………………………………....13 The genus Normandia.……………………………………………………....14 The genus Durringtonia.…………………………………………….……....15 The genus Nertera….………………………………………………..……....15 Morphological circumscription of Coprosma…………………………………......17 Floral and fruit morphology………………………………………………....17 Leaves and interpetiolar stipules…………………………….……………....18 Secondary Growth and Habit……………………………………………......19 Current systematic treatment of Coprosma…………………………………..…...20 Dissertations aims and hypotheses……………………………………….......…....21 Aim A. To investigate the origins of Hawaiian Coprosma taxa...……….....22 Aim B. To understand the historical biogeography of Pacific Coprosma.....23 Aim C. To understand the morphological relationships among Coprosma taxa and their evolutionary implications……...………………………………….23 CHAPTER 2: BIOGEOGRAPHIC INSIGHTS ON PACIFIC COPROSMA (RUBIACEAE) INDICATE TWO COLONIZATIONS OF THE HAWAIIAN ISLANDS..........................................................................................................................25 Abstract…………….……………………………………………...…………….....25 Introduction…………….……………………………………………………….....26 Materials and Methods………………………………………………………….....30 Sampling…………….……………………………………………...…….....30 DNA extraction, amplification and sequencing…………….……………....31 Phylogenetic and biogeographic analyses…………….…….……………....36 Results…………….…………………………………………………………….....38 vii Maximum Likelihood and Bayesian Inference Analyses..……….………...38 Biogeographic Relationships………………..……………………………....40 Discussion…………….…………………………………………..…………….....44 CHAPTER 3: BIOGEOGRAPHY AND EVOLUTIONARY DIVERSIFICATION OF INSULAR COPROSMA (RUBIACEAE): ONE OF THE LARGEST AND MOST WIDELY DISTRIBUTED GENERA IN THE PACIFIC OCEAN………………………………………….............................................................51 Abstract…..…………………………………………………….……………….....51 Introduction…………………………………………………….……………….....53 Materials and Methods………………………………………………………….....59 Sampling………………………………………………………………….....59 DNA extraction, amplification and sequencing……………………….…....59 Phylogenetic and morphological analyses……………………….……….....60 Ancestral state reconstructions………...………………………………….....62 Molecular dating analyses…………………..…………………………….....63 Results…………………………………………………………………….…….....64 Phylogenetic Analyses…………………………...……………………….....64 Geographic origin(s) of Coprosma s.s. and non-New Zealand Pacific Taxa……………………………………………………………….......65 Morphological trait evolution in dispersal and establishment………...68 Reproductive Strategy……………………...……………………….....68 Habit………………………………………..……………………….....68 Fruit Color...………………………………..……………………….....68 Discussion……………………………………………………………………….....70 Character evolution aiding dispersal and establishment of Coprosma s.s.....70 Historical biogeography of Coprosma s.s. ……………………………….....73 Time, origin, and extensive radiation in New Zealand……..…………….....73 Dispersals from New Zealand to elsewhere…...…………………………....78 Conclusions……………………………………….…………………………….....81 CHAPTER 4: MORPHOLOGICAL, ECOLOGICAL AND MOLECULAR SUPPORT FOR NEW SUBGENERIC RELATIONSHIPS OF COPROSMA (RUBIACEAE)................................................................................................................83 Abstract…...……………………………………….…………………………….....83 Introduction……………………………………….…………………………….....85 Taxonomic History……………………….…………….…………...…………......85