Craniometric analysis of unaffiliated Native American remains in Texas Courtney C. Siegert1, Kate Spradley1, and Michelle D. Hamilton1 Department of Anthropology, Texas State University INTRODUCTION Texas prehistory is defined mainly based on stylistic material culture, specifically projectile points and ceramics. The prehistoric population structure of Texas is less understood, as the availability of published osteological analyses are lacking for the region. The purpose of this research is to explore the population structure of archaic and prehistoric peoples of Texas using craniometric data in an effort to better understand population structure. Cranial morphology is highly heritable and therefore can be used as a proxy for understanding biological distance and population relationships (Harding 1990; Relethford 2004; Carson 2006). DISCUSSION The chronology of Texas prehistory can be roughly divided into three major categories including the Paleo-Indian (late Pleistocene-6000 BC), Archaic (6,000 BC-700AD), and Late Prehistoric (700AD-1600 AD). Archaeological evidence suggests extensive trade connections and cultural diffusion during the Late Prehistoric (Hester and Turner 2010). Additionally, the Texas chronological periods may be too broad to accurately capture morphological changes over time. These factors may account for the large degree of variation seen within the prehistoric Texas samples: Caplan Mound Site (41GV1) has been defined culturally as a Caplan Phase campsite dating to the Late Prehistoric (Rose et al. 1999). Findings suggest a high degree of variation. Mitchell Ridge Site (41GV66) is an open campsite with an Archaic, Late Prehistoric, and Historic component (Texas Archaeological Sites Atlas). The two individuals included in this analysis are most similar to each other, followed by the Indian Knoll, Ainu and Windover samples. Owl Creek Shelter (41BL3) is a rockshelter in Bell County dating from the Prehistoric with extensive occupation. Individual 41BL3675 is most similar to Arikara and Blackfeet female samples based on matrix distances, while individual 41BL3651 is most similar to Ainu female and other Archaic samples from differing geographic locations. Owl Creek Shelter populations show a lesser degree of variability than Caplan Mound Site. Loeve Fox Site (41WM230) is located in Williamson County, dating from the Middle Archaic to the late Neoarchaic (about 700 AD) (Texas Archaeological Sites Atlas), and is most similar to the Ainu male sample (D2= 1.29052). Conejo Shelter (41VV162) is a multicomponent rockshelter dating from Paleoindian occupation to the early Historic (Texas Archaeological Sites Atlas), and is most similar to the Ainu female sample (D2= 4.70724). Due to the degree of geographic distance between Japan and Texas, the similarity between the Ainu, Conejo Shelter, and Loeve Fox samples may reflect common ancestry. Note: many of the Texas sites used in this project are multicomponent, spanning multiple chronological periods, so their assignment into specific time periods is based on a combination of absolute and relative dating methods. MATERIALS AND METHODS Unaffiliated human remains (n=15) housed at the Texas Archaeological Research Laboratory came from sites in Galveston County (41GV1, 41GV66) along the coastline, Bell (41BL3), Williamson(41WM230), and Coryell Counties (41CV14) in central Texas, and Val Verde County (41VV162, 41VV422) in west Texas. Comparative population groups consisting of both males and females were also included in analysis, TABLE 1. TABLE 1: Comparative populations The full suite of landmark data were collected using a Microscribe® G2 3D digitizer and 3Skull software (Ousley 2010), FIGURE 1. Variables and individuals with missing values were removed from analysis to obtain a complete data set Variables included in analysis: GOL, BBH, OBH, OBB, DKB, WMH, FRC, PAC, OCC In order to assess the biological relationships among the Texas samples and other Native Americans, a D2 matrix was obtained in SAS 9.3.2. The D2 distance matrix was double centered and the eigenvectors and eigenvalues generated using the EIGEN function in NTSYS 2.2r, making analysis less subject to errors caused by small sample size Figure 1: Digitizing cranium using Microscribe® G2 3D digitizer RESULTS FIGURE 2B: Plot of eigenvectors The first axis largely separates according to time period, with positive values being associated with groups from older temporal components, FIGURE 2A. The second axis separates the groups mainly by sex, with positive values generally being associated with females and negative values being associated with males, FIGURE 2B. Generally, the Texas sample clusters with the Archaic comparative samples with some exceptions. The Ainu sample, although coming from Japan, is most similar to Prehistoric and Archaic Texas Samples. Group N Time Period Location Site Reference Ainu Historic Japan Howell’s 1973 Arikara 42 Fort Sully, South Dakota Herrmann et al. 2006 Blackfeet 25 Montana (various loc.) Jantz, personal communication Indian Knoll 11 Archaic Paradise, Kentucky Numic 29 Great Basin (various loc.) Peru 55 unknown Yauyos, Peru Howells 1973 Santa Cruz 51 Santa Cruz, California Windover 21 Titusville, Florida Dickel 2002 Zuni 24 New Mexico Hodge 1937 Lipan Apache 2 Mission San Lorenzo, Texas Newcomb 1969 Conejo Shelter Val Verde County, Texas Alexander 1974 41WM2303 AINUM FIGURE 2A: Plot of eigenvectors Female Male Indeterminate CONCLUSION The purpose of the current research is to explore the population structure within prehistoric Native American groups of Texas using craniometric data and biological distance analysis. Preliminary results show that Texas prehistoric population groups display a range of variation. AINUM 41WM2303 ACKNOWLEDGEMENTS Many thanks to the Texas Archaeological Research Laboratory and staff, specifically Marybeth Tomka and Stacy Drake, for providing access to the curated osteological collection. Thank you to Dr. Steve Black for assisting with site background research and to Dr. Richard Jantz for use of previously collected data. REFERENCES For a digital copy of this presentation and a list of references, please scan QR code, visit goo.gl/0BTtGl, or email csiegert@txstate.edu.