Mitochondrial DNA Variation in the Fijian Archipelago by Diana A
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Mitochondrial DNA variation in the Fijian Archipelago By Diana A. Taylor Submitted to the graduate degree program in Anthropology and the Graduate Faculty of the University of Kansas in partial fulfillment of the requirements for the degree of Master of Arts. ________________________________ Chairperson Dr. Alan J. Redd ________________________________ Dr. James H. Mielke ________________________________ Dr. Maria E. Orive Date Defended: April 5, 2012 The Thesis Committee for Diana A. Taylor certifies that this is the approved version of the following thesis: Mitochondrial DNA variation in the Fijian Archipelago ________________________________ Chairperson Dr. Alan J. Redd Date approved: April 18, 2012 ii ABSTRACT The purpose of this thesis is to explore the evolutionary history of Fijians with respect to maternal ancestry. Geographically situated between Melanesia and Polynesia, Fiji has been a place of cultural exchange between Pacific Islanders for at least three thousand years. Traditionally, Fijians have been classified as Melanesians based on geography, culture, and skin pigmentation. However, Fijians share much in common linguistically, phenotypically, and genetically with Polynesians. Four questions motivated my research. First, are Fijians more Melanesian or Polynesian genetically? Second, is there a relationship between geography and genetic variation? Third, are Rotumans more similar to Fijians or Polynesians? And lastly, are Lau Islanders more similar to Fijians or Tongans? I used maternally inherited mitochondrial DNA (mtDNA) as my tool of investigation. In addition, I used various lines of anthropological evidence to synthesize my conclusions. I examined a sample of over 100 Fijians from five island populations, namely: Viti Levu, Kadavu, Vanua Levu, the Lau Islands, and Rotuma. In addition, my sample included two Melanesian and two Polynesian island populations. The results of the analyses place Fijian mtDNAs intermediate between Melanesians and Polynesians. However, the Fijians appear slightly more Polynesian than Melanesian based on a Multidimensional Scaling (MDS) plot and a comparison of frequencies of Near-Oceanic versus Asian mtDNA lineages. I did not detect a genetic- geographic association. Other factors besides geographic distance shaped maternal migration patterns. This is the first genetic study of Rotumans. The Rotumans are very similar to Polynesians genetically. The Rotuman sample has little genetic diversity suggesting that a maternal genetic bottleneck occurred at some point in their history. Finally, Lau Islanders are as diverse as the Fijian mainlanders, which supports a hypothesis that the Lau Group historically functioned as a crossroads for Fijians and Tongans. Lau Islanders are more similar to Tongans than they are to other Fijian Islanders (excluding Rotuma) based on a MDS plot and a comparison of frequencies of Near-Oceanic versus Asian mtDNA lineages. iii This thesis is dedicated to my family, who support me through all the ‘chutes and ladders’ of life: My mother and grandmother for watching over me; my father and second mother, Vicky, for endless support and love; my brothers, Grant and Dane, for keeping their big sister in line; my aunts, Rita and Patricia, for taking me under their wings when I needed guidance; and finally, a special thanks to Steven and Michaela for helping me survive this thesis and graduate school in general. I love you all. iv ACKNOWLEDGEMENTS First and foremost, I thank the participants of this study; their curiosity to learn more about their maternal ancestry was refreshing and I hope the results from this project offer them personal insight. I would also like to sincerely thank Dr. Anand P. Tyagi, and The University of the South Pacific for making this study possible. Two of my committee members, Dr. James H. Mielke and Dr. Maria E. Orive, helped to make this thesis a better product and I am incredibly thankful for their support. Special thanks to Dr. Geetanjali Tiwari for collecting biological samples and interviewing participants. Also, thanks to Michaela Beals for assisting with biological sample processing. Finally, and most importantly, I would like to thank Dr. Alan J. Redd for guiding me and this project and providing an endless amount of support. Dr. Redd assisted me with all facets of this project and I am incredibly thankful to have had the privilege of working as his graduate student. This project was partially funded by a Carol A. Clark award from the University of Kansas Department of Anthropology. Thank you to the members of the Carol A. Clark committee for offering support to this project. v Table of Contents CHAPTER 1: INTRODUCTION....................................................................................... 1 CHAPTER 2: BACKGROUND......................................................................................... 5 2.1 ARCHEOLOGY IN THE FIJIAN ARCHIPELAGO............................................... 5 2.1.1 History of Near Oceania .................................................................................... 5 2.1.2 History of the Lapita Expansion in Near Oceania ............................................. 7 2.1.3 History of the Lapita Expansion in Remote Oceania....................................... 10 2.1.4 History of the Lapita Expansion in the Fijian Archipelago ............................. 13 2.1.5 Vanuatuan influence on the islands of Fiji ...................................................... 19 2.1.6 Polynesian influence on the islands of Fiji ...................................................... 21 2.2 LANGUAGE STUDIES IN THE FIJIAN ARCHIPELAGO ................................ 26 2.2.1 Papuan languages............................................................................................. 26 2.2.2 Austronesian language expansion.................................................................... 27 2.2.3 Fijian language................................................................................................. 28 2.3 KINSHIP ORGANIZATION IN THE FIJIAN ARCHIPELAGO......................... 33 2.3.1 Post-marital residence rules in Oceanic populations ....................................... 33 2.4 BIOLOGICAL ANTHROPOLOGY IN THE FIJIAN ARCHIPELAGO.............. 35 2.4.1 Near-Oceanic mitochondrial DNA .................................................................. 35 2.4.2 Mitochondrial DNA associated with the Austronesian expansion .................. 42 2.4.3 The Austronesian expansion: Evidence from the mitochondrial DNA 9 base pair deletion .............................................................................................................. 47 2.4.4 Austronesian colonization of Remote Oceania................................................ 48 2.4.5 Sex-biased genetics in Austronesian-founded populations.............................. 50 2.4.6 Biological studies of the Fijian people............................................................. 51 2.4.7 Fijian genetics .................................................................................................. 55 CHAPTER 3: MATERIALS AND METHODS .............................................................. 60 3.1 MATERIALS.......................................................................................................... 60 3.1.1 Study participants............................................................................................. 60 3.1.2 Island populations examined............................................................................ 60 3.2 LABORATORY METHODS................................................................................. 61 3.2.1 Protocol for mtDNA sample processing.......................................................... 61 3.2.2 MtDNA sequencing ......................................................................................... 62 3.2.3 MtDNA haplogroup assignment...................................................................... 63 3.3 METHODS OF ANALYSIS .................................................................................. 64 3.3.1 Haplogroup frequency classification ............................................................... 64 3.3.2 Haplotype sharing ............................................................................................ 64 3.3.3 Measurements of diversity within populations................................................ 65 3.3.4 Measurement of diversity among populations................................................. 66 3.3.5 Measurement of multivariate distances ........................................................... 67 3.3.6 Tree phylogeny ................................................................................................ 68 CHAPTER 4: RESULTS.................................................................................................. 70 4.1 MITOCHONDRIAL DNA RESULTS................................................................... 70 4.1.1 Mitochondrial DNA (mtDNA) haplogroup assignment .................................. 70 4.1.2 Haplogroup frequency visualization................................................................ 75 4.1.3 Haplotype sharing ............................................................................................ 76 4.1.4 Measurements of diversity within populations................................................ 78 vi 4.1.5 Measurements of diversity among populations ............................................... 81 4.1.6 Measurement of multivariate distances ..........................................................