University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 2016 A Comparison of the Utility of Craniometric and Dental Morphological Data for Assessing Biodistance and Sex- Differential Migration in the Pacific Islands Brittney A. Eubank Follow this and additional works at: https://scholarworks.umt.edu/etd Part of the Biological and Physical Anthropology Commons, and the Multivariate Analysis Commons Let us know how access to this document benefits ou.y Recommended Citation Eubank, Brittney A., "A Comparison of the Utility of Craniometric and Dental Morphological Data for Assessing Biodistance and Sex-Differential Migration in the Pacific Islands" (2016). Graduate Student Theses, Dissertations, & Professional Papers. 10655. https://scholarworks.umt.edu/etd/10655 This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. A Comparison of the Utility of Craniometric and Dental Morphological Data for Assessing Biodistance and Sex-Differential Migration in the Pacific Islands By Brittney A. Eubank B.A., Anthropology, University of Montana, Missoula, MT, 2013 Thesis Paper Presented in Partial Fulfillment of the Requirements for the Degree of Master of Arts Anthropology The University of Montana Missoula, MT Spring 2016 Approved by: Dr. Randall Skelton, Chair Department of Anthropology Dr. Meradeth Snow Department of Anthropology Dr. Corey Ragsdale Department of Anthropology Dr. Kevin McKelvey USDA Forest Service 1 Abstract Eubank, Brittney A., M.A., Spring 2016 Anthropology A Comparison of the Utility of Craniometric and Dental Morphological Data for Assessing Biodistance and Sex-Differential Migration in the Pacific Islands Chairperson: Randall Skelton Genetic analysis of maternally-inherited mitochondrial DNA and the paternally-inherited Y- chromosome yield contrasting pictures of movement of peoples into the Pacific Islands. A possible explanation for this discrepancy is a matrilocal residency pattern practiced by early Pacific settlers, in which Melanesian men were brought into settler communities to intermarry with local women, yielding a higher intrapopulation variance and lower interpopulation variance exhibited in males compared to females. This research investigates the possibility of sex-differential migration in the Oceanic populations of Easter Island, Fiji, Guam, Mokapu, and New Britain through analysis of biodistance based on dental morphological trait frequencies and craniometric measures while simultaneously comparing the utility of these two different data types, dental non-metrics and continuous cranial measurements, to determine whether these two types of data can be usefully combined or utilized interchangeably to represent underlying genotypic variation. Using Mean Measure of Divergence and Mahalanobis distance, variation for these populations was modelled with Principal Coordinatess Analysis, Generalized Procrustes Analysis, Mantel tests, discriminant analysis, and K-means clustering. Overall, the dental data was not found to be consistently more variable between the sexes and populations than craniometric data, indicating that if craniometric measurements are smoothed out by environmental factors while dental morphology is more canalized, this effect is subtle for this region and these particular samples. Additionally, estimates of possible residence patterns were not in agreement between analyses, indicating that residency was likely only slightly unilocal if not ambilocal, depending on population. However, uneven sample sizes and the small number of populations available for study likely affected the ability to draw out conclusive inferences about the peopling of this vast and complex region. i Acknowledgements I am greatly appreciative to the many individuals that helped to make this project possible and have enlightened and supported me throughout my graduate career. I would like to thank Dr. G.R. Scott for generously providing me with dental data. I would like to thank my committee members, Dr. Meradeth Snow, Dr. Corey Ragsdale, and Dr. Kevin McKelvey for not only their willingness to sit on this committee, but for their advice and help with many aspects of this project. I would like to thank Dr. Randall Skelton for his unwavering guidance and support throughout both my undergraduate and graduate pursuits. It is due to his constant encouragement and reassurance of my capabilities that I have been inspired to pursue this field. Finally, I thank my family for their support of my academic career; my parents and sisters, for always lending a listening ear, a helping hand, and an appreciation for my path; and Joshua and Chloe, for being the inspiration for all that I do and for brightening every day of my life. We made many sacrifices together to allow me to accomplish this goal, and I am beyond grateful for the love and support you have given me throughout this journey. ii Table of Contents Title: A Comparison of the Utility of Craniometric and Dental Morphological Data For Assessing Biodistance and Sex-Differential Migration in the Pacific Islands Abstract……………………………………………………………………………………………i Acknowledgements……………………………………………………………………………….ii Table of Contents………………………………………………………………………………...iii List of figures……………………………………………………………………………………..v List of tables……………………………………………………………………………………...vi Chapter 1: Introduction……………………………………………………………………………1 Chapter 2: Literature Review 2.1 Migrations into the Pacific Islands – linguistic, archaeological, and genetic evidence.5 2.2 Post-marital residence pattern………………………………………………………..14 2.3 Biodistance and investigation of social organization through skeletal remains……..22 2.4 Craniometrics and dental morphology……………………………………………….38 Chapter 3: Materials and Methods 3.1 Samples………………………………………………………………………………49 3.1.1 Turner Data (dental)………………………………………………………..51 3.1.2 Howells Data (craniometric)……………………………………………….51 3.2 Methods………………………………………………………………………………52 3.2.1 Preprocessing………………………………………………………………52 3.2.2 Statistical Analysis…………………………………………………………57 Mean Measure of Divergence……………………………………………57 Mahalanobis Distance……………………………………………………57 Principal Components Analysis………………………………………….58 Generalized Procrustes Analysis…………………………………………58 Mantel Tests…………………………………………………………...…59 iii Determinant Analysis…………………………………………………….60 K-Means Clustering……………………………………………………...60 Chapter 4: Results………………………………………………………………………………..62 Chapter 5: Discussion……………………………………………………………………………97 5.1 Comparing sexes…………………………………………………………………….98 5.2 Comparing data types……………………………..…...…………………………...103 5.3 Comparing both sexes and data types……………………...……………………….105 5.4 Limitations………………………………………………………………………….110 5.5 Future Research…………………………………………………………………….114 Conclusion……………………………………………………………………………………...116 Bibliography……………………………………………………………………………………117 iv List of Figures Figure 1: Map of Oceania…………………………………………………………………………6 Figure 2: Distribution of mitochondrial DNA haplotypes in Oceania…………………………...11 Figure 3: Distribution of Y-chromosome haplotypes in Oceania………………………………..13 Figure 4: The main predictors of marital residence pattern……………………………………...17 Figure 5: Graph showing where the different in trait frequencies is equal to the correction term as a function of sample size for MMD……………………………………………………………...27 Figure 6: Model of quasicontinuous variation and threshold effect……………………………..35 Figure 7: Male versus cranial morphology and sexually dimorphic features……………………36 Figure 8: Examples of ASUDAS casts of graded expression for UI1 shoveling and Carabelli’s cusp………………………………………………………………………………………………39 Figure 9: Example of ASUDAS score sheet……………………………………………………..41 Figure 10: Map of the Pacific Islands with sample populations highlighted in yellow………...49 Figure 11: PCo plots for males and females based on MMD for dental scores………………...67 Figure 12: PCo plots for males and females based on Mahalanobis for craniometric measurements……………………………………………………………………………………68 Figure 13: PCo plots for all individuals based on MMD for dental scores and Mahalanobis for craniometric measurements……………..……………………………………........................….69 Figure 14: 3D plots of axes 1-3 for males based on Mahalanobis for craniometric measurements…………………………………………………………………………………….70 Figure 15: 3D plots of axes 1-3 for females based on Mahalanobis for craniometric measurements…………………………………………………………………………………….71 Figure 16: 3D plots of axes 1-3 for both sexes based on Mahalanobis for craniometric measurements…………………………………………………………………………………….72 Figure 17: Residuals by population for Male Cranial/Female Cranial consensus configuration..77 Figure 18: Residuals by population for Male Dental/Female Dental consensus configuration…77 Figure 19: Residuals by population for Female Dental/Female Cranial consensus configuration……………………………………………………………………………………..78 Figure 20: Residuals by population for Male Dental/Male Cranial consensus configuration…..78 Figure 21: Variance by configuration and by factor for Male Cranial/Female Cranial consensus configuration…………………………………………………………………………………….80 v Figure 22: Variance by configuration and by factor for Male Dental/Female Dental consensus configuration……………………………………………………………………………………..81 Figure 23: Variance by