Secular trends in Cherokee cranial morphology: Eastern vs Western bands

Temporal trends in craniometric estimates of admixture for a modern American sample

OBJECTIVES

Temporal trends in craniometric estimates of admixture are investigated for three U.S. populations in the FDB. Patterns of association between birth years and posterior probabilities of cluster membership are identified to assess how these proportions of admixture have changed over recent time. Demographic and genetic data correlates, patterns of morphological expression, and shifts in source populations are evaluated.

MATERIALS AND METHODS

Estimates of three-way admixture were obtained for 1,521 individuals of documented population, sex, and birth years that span the 20th century. Correlations were calculated between birth years and admixture proportions for members of each FDB population. Population and sex-specific admixture variation was further assessed by ANOVA and regression. Correlation analysis was used to identify, per population, which of the cranial measurements change in dimension under increased or decreased admixture.

RESULTS

Admixture proportions differ significantly by population and change over time. No sex differences are detected. Analysis of the relationship between admixture proportions and ILDs finds that admixture drives morphological change in areas of the cranium known to vary among populations. Results agree with prior work on secular change.

DISCUSSION

Findings reveal a progressive increase in White-European population admixture for the self-identified Black individuals, a recent demographic shift toward the increased representation of Hispanic individuals carrying greater Native American ancestry, and reduction in admixture for White individuals that suggest a loss of diversity over time. Changes in admixture produce tractable differences in morphological expression. Both sexes exhibit similar admixture proportions and self-identification patterns. Observed diachronic trends are corroborated by information on recent U.S. demographic change.

The vanishing Black Indian: Revisiting craniometry and historic collections

OBJECTIVES

This article uses craniometric allocation as a platform for discussing the legacy of Samuel G. Morton's collection of crania, the process of racialization, and the value of contextualized biohistoric research perspectives in biological anthropology.

MATERIALS AND METHODS

Standard craniometric measurements were recorded for seven Seminoles in the Samuel G. Morton Crania Collection and 10 European soldiers from the Fort St. Marks Military Cemetery; all individuals were men and died in Florida during the 19th century. Fordisc 3.1 was used to assess craniometric affinity with respect to three samples: the Forensic Data Bank, Howells data set, and an archival sample that best fits the target populations collected from 19th century Florida. Discriminant function analyses were used to evaluate how allocations change across the three comparative databases, which roughly reflect a temporal sequence.

RESULTS

Most Seminoles allocated as Native American, while most soldiers allocated as Euro-American. Allocation of Seminole crania, however, was unstable across analysis runs with more individuals identifying as African Americans when compared to the Howells and Forensic Data Bank. To the contrary, most of the soldiers produced consistent allocations across analyses. Repeatability for the St. Marks sample was lower when using the archival sample database, contrary to expectations. For the Seminole crania, Cohen's κ indicates significantly lower repeatability. A possible Black Seminole individual was identified in the Morton Collection.

DISCUSSION

Recent articles discussing the merits and weaknesses of comparative craniometry focus on methodological issues. In our biohistoric approach, we use the patterning of craniometric allocations across databases as a platform for discussing social race and its development during the 19th century, a process known as racialization. Here we propose that differences in repeatability for the Seminoles and Euro-American soldiers reflect this process and transformation of racialized identities during 19th century U.S. nation-building. In particular, notions of whiteness were and remain tightly controlled, while other racial categorizations were affected by legal, social, and political contexts that resulted in hybridity in lieu of boundedness.