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This study examines the specific African ancestry of the "Gullah" African Americans of Lowcountry South Carolina. The proximate goal was to use biological data from Lowcountry populations to test the conclusions of previous cultural, historical, and linguistic research. The ultimate goal was to further knowledge of complex diseases prevalent in African American populations. When ancestral populations are correctly identified, medical researchers can target the most informative comparative populations for studies of genetic and environmental causes of disease. The proposed Lowcountry/Sierra Leone relationship promoted by Opala (1987) generated new interest and pride in Gullah/Geechee heritage. However, other African connections to the Lowcountry have been somewhat neglected. This study investigates other likely associations between West Africa and the Lowcountry using biological evidence. Chapters 1-3 summarize the history, cultural traditions, and previous studies of the African Americans of the South Carolina Lowcountry. Based upon this information, the biological analysis in Part 11 tests the proposed affinity of Lowcountry African Americans with peoples of West Africa. Chapter 4 describes the utility of accurate biological description of African Americans and the population dynamics that have affected their genome(s). Chapter 5 presents a brief introduction to abnormal p-globin haplotypes and their application to the question of specific African American ancestry. The regional homogeneity of these markers in Africa presents the unique opportunity to identify the origins of two ancestors of individuals with sickle cell anemia (Hb SS). Chapter 6 examines the anthropometric affinity and population structure of Lowcountry African Americans (Fst, coefficients of kinship, generalized distances) using comparative metric data from available African populations. The genetic results indicate the expected relationships to Upper Guinea and equatorial Africa, but a stronger affiliation with peoples of the Gold and Slave Coasts than expected from cultural and historical evidence. The metric data indicates that the Gullah population exhibits a morphology that closely resembles those of West African populations and suggests relationships with populations that are overlooked in the cultural and historical hypotheses. All results indicate that Lowcountry African Americans represent a biological amalgam with identifiable affinities with all major regions of West Africa.

This study attempted to augment the Stout and Paine (1992) and Stout and colleagues' (1996) methods of histological aging for the clavicle. In the 1992 study, the predictive equation was generated from a sample of only 40 individuals taken from an autopsy population (mean ages 28.6 years) with no prior sampling strategy. The 1996 expansion (Stout et al., 1996) tested the 1992 equation, added 41 males and 42 females from a Swiss cemetery sample to the original autopsy sample to generate a new predictive equation based on all 123 individuals. In this study, an independent autopsy population was used to construct a sample of 95 individuals with a random stratified profile and an approximately equal number of individuals from each decade between the ages of 22 and 88 years. Roughly equal numbers of males (n = 50) and females (n = 45) were included in the sample. Construction of an independent sample assured comparability of all measures and excluded possibility of intraobserver error. This sample was used to achieve four research goals: 1) Test for sexual dimorphism in the OPD variable. 2) Generate predictive equations using inverse calibration, the method most commonly used in histological aging methods, achieved by regressing age upon the histological variable OPD. 3) Test the 1992, 1996, and current equations using both the Stout and Paine (1992) and the current samples. 4) Generate predictive equations for the Stout and Paine (1992) and current sample using classical calibration, which is regression of the OPD variable upon age. The generation of predictive equations using both the inverse and classical calibration allowed comparison of the characteristic distributions associated with each, and tests for accuracy of their estimates. While females exhibited a greater correlation between age and the OPD variable (r2 = .5763) than males (r2 = .2489), this difference did not result in a significant difference in the OPD variable between males and females: Based on the full sample, the relationship between age and the OPD variable was found to be highly significant (p < .0001). A linear response and plateau function (lrp) was performed on the data to locate the most likely asymptote, a point where further remodeling activity cannot be detected. The lrp placed the most likely start of the plateau at the age of 73 years. Based upon this result, a subsample of those individuals between the ages of 22 and 73 years were used to generate all predictive equations (n = 74). The inverse predictive equation reported by Stout and colleagues (1996) provided the most accurate age estimates for the current sample, followed by the equation produced from the subsample in the current study. The classical calibration equations generated for the current subsample and Stout and Paine (1992) samples both resulted in greater mean squared error values than the their inverse counterparts when applied to the full current sample. Comparison of the mean squared error values for the classical and inverse predictive equations for the current subsample (n = 74) showed that while the inverse calibration equation shows evidence of slight bias, the error for the inverse calibration estimates is smaller than those for the classical equation across all age ranges (22 - 73 years). This suggest the inverse form of the predictive equation is the calibration method of choice for histological age estimation for the clavicle.