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Melody D. Ratliff, B.A .

Melody D. Ratliff, B.A . Department of Anthropology, The University of Montana, Missoula, MT. Introduction

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Melody D. Ratliff, B.A .

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  1. Melody D. Ratliff, B.A. Department of Anthropology, The University of Montana, Missoula, MT Introduction When assessing ancestry in a forensic context, individuals are generally classified into one of four categories: belonging to European ancestry, African ancestry, Asian ancestry, or Native American ancestry. Individuals from the Southeast Asian and Pacific Island regions are usually phenotypically classified in the Asian categorization though as previous researchers have shown, there is an interregional clinal pattern in this area of the world that would theoretically cause individuals from Southeast Asia and the Pacific Islands to have slightly differing frequencies of discrete traits than those of mainland Asia. I suggest that there will be slight frequency differences between the mainland Asian population and the Southeast Asian population, as well as between the Southeast Asian population and the Pacific Island population. I also suggest that there will be statistically significant differences between the Asian population and the Southeast Asian/Pacific Island populations for at least some traits. Results Results Results The Anterior Nasal Spine (ANS), the Inferior Nasal Aperture (INA), Interorbital Breadth (IOB), Nasal Aperture Width (NAW), Nasal Bone Contour (NBC), Post Zygomatic Tubercle, (PZT), and Zygomaticomaxillary Suture Course (ZSC) were all found to be significantly different between the groups at the 95% confidence level. The ANS, IOB, and NBC exhibit a separation between the Asian population frequencies and the Pacific Islands/Southeast Asian population frequencies. The INA in Table 1 appears to exhibit a clinal pattern moving geographically west to east, Asia to Southeast Asia to the Pacific Islands, changing from a score of 3 (right-angle) to a score of 1(sloping or guttering). The NAW in Table 2 also appears to have this same clinal pattern moving toward a narrow NAW as you move westerly. The PZT in Table 3 also appears to have to show clinality from a larger PZT to a smaller PZT from mainland Asia to Southeast Asia to the Pacific Islands. In Table 9, the ZSC has a very strong inclination toward a score of jagged/S-shaped in mainland Asians and a shift away from this score in Southeast Asians and Pacific Islanders. Also noted in Table 4, there is a strong shift toward a straight ZSC in Southeast Asians and Pacific Islanders, noting clinality of this trait over the geography. Nasal Overgrowth (NO) and Post-Bregmatic Depression (PBD) were found not to be significantly different between the groups. Morphoscopic Trait Frequencies of Southeast Asians and Pacific Islanders: A Preliminary Examination INA 3 INA 1 I NA 2 PZT: 0 PZT: 1 Materials and Methods Cranial morphoscopic data were collected using the Macromorphoscopics module of the program Osteoware1 which provides the user with a particular set of assessments in order to help standardize the assessments. Osteoware1 allows for the recording of 16 morphoscopic traits, of which 9 are recorded for this study. The traits are as follows: Anterior Nasal Spine (ANS), Inferior Nasal Aperture (INA), Interorbital Breadth (IOB), Nasal Aperture Width (NAW), Nasal Bone Contour (NBC), Nasal Overgrowth (NO), Post-Bregmatic Depression (PBD), Posterior Zygomatic Tubercle (PZT), Zygomaticomaxillary Suture Course (ZSC). These traits were scored for 30 individuals from the University of Pennsylvania Museum of Archaeology and Anthropology’s physical anthropology skeletal collection and 136 individuals from the Smithsonian National Museum of Natural History for a total of (n=166). The Southeast Asian population sample consists of 94 individuals from the Philippine Islands, Indonesia, Malaysia, Borneo, Sumatra, and Sri Lanka. The Pacific Island population sample consists of 72 individuals from French Polynesia, Fiji, Papua New Guinea, Solomon Islands, Vanuatu, Samoa, and Easter Island. The Asian comparison sample was provided by Dr. Joe Hefner and consists of 74 Japanese and Chinese individuals. For this study, the Pacific Island population groups together the far island populations as well as Micronesian and Melanesian populations. This preliminary study compares the frequencies of morphoscopic traits between Southeast Asians, Pacific Islanders, and mainland Asians. Using SPSS2, cross-tabulation tables were created to show the frequencies for each trait. Chi-square analyses were performed for each trait to determine if there is a significant difference between the three groups for each trait. INA 5 INA 4 PZT: 3 PZT: 2 Conclusions The frequencies of seven of the nine traits used for this study were found to be significantly different between the mainland Asian, Southeast Asian, and Pacific Island groups at the 95% confidence level. Three of the nine traits exhibit a clustering of Southeast Asian and Pacific Island individuals and a separation between the mainland Asian group and the Southeast Asian/Pacific Island group. Four of the nine traits exhibit a clinal distribution of the frequencies of trait expression, moving geographically from mainland Asia to Southeast Asia to the Pacific Islands. References • Osteoware [computer program] Smithsonian Institute, Washington, D.C. 20013-7012, 2011. https://osteoware.si.edu/content/software-downloads • SPSS Inc. Released 2009. PASW Statistics for Windows, Version 18.0. Chicago: SPSS Inc NAW 2: medium NAW 3: broad NAW 1:narrow ZSC: 2 ZSC: 1 ZSC: 0 Acknowledgements I would like to thank Dr. Joe Hefner for his guidance using the Morphoscopics module of Osteoware and for providing me with his expertise in this area of research, as well as the Asian comparison data set. I would like to thank the Pennsylvania Museum of Archaeology and Anthropology, Dr. Janet Monge, the Smithsonian Institute, and Dr. David Hunt for their help and for allowing me to use the collections. I would also like to thank my advisor, Dr. Randy Skelton for his guidance with this research.

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