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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Black-American anthropology | 3/5 | https://en.wikipedia.org/wiki/Black-American_anthropology | reference | science, encyclopedia | 2026-05-05T15:10:09.399989+00:00 | kb-cron |
== Physical anthropology == Physical anthropology is the study of the biological features of ancient and modern humans, including health, nutrition, mortality, genetics and physical variability in the past and present, and of humans' primate relatives and fossil ancestors. These studies are all informed by modern evolutionary theory and take their place in anthropology rather than biology because they consider the biocultural context within which human evolution, adaptation and variation occur. Historically, however, physical anthropology focused on the physical variation observed among living peoples and assumed that a fixed number of definitive physical "types" lay behind this variation. These fundamental types were identified as the different "races" of humankind and were thought to be recognizable also in the fossil or skeletal record. Contemporary physical anthropologists recognize, however, that race is not a useful biological concept when applied to humans. Although many people believe that they can distinguish "races" on the basis of skin color, more of the variation in human genetic makeup can be attributed to differences within these so-called races than between them. Furthermore, the observable and unobservable (to the eye) physical variation is so great and complex that there are no criteria that can satisfactorily segregate all individuals into one race or another. The movement in historic times of genes throughout different populations of the world and the sharing of genes through interbreeding ensures that different populations around the world are becoming more alike. Unlike the classic typological approach, which interprets variation in physical form as resulting only from the admixture of races, contemporary approaches to understanding variation also take into account genetic and physiological adaptations to local and regional environmental factors, such as the intensity of ultraviolet radiation or ambient temperature and humidity. Conceptually, biological affinity expresses a continuum of relationship that reflects genetic mixing (gene flow) from different local and regional areas in antiquity in addition to the influences of other evolutionary factors, such as natural selection and genetic drift. Due to shared ancestry and their ethnogenesis within the land that would become the United States, Black-Americans exhibit morphological traits consistent with their founding populations. The formation of a unique Black-American ethnicity was noted by anthropologists in the early 20th century, "[t]hey noticed a "transformation" in the American Black population that Melville J. Herskovits (1928) termed "racial crossing." They began to publish, from an anthropological view, articles and books to help American Blacks understand their biological origins and culture. Herskovits did much to understand what he termed the "American Negro" and tried to help all Americans in the early 20th century understand that American Blacks were a significant portion of the population and that they have adapted to this environment both culturally and biologically, and are therefore American." Since the early 18th century, Black-Americans have remained morphologically distinct, yet somewhat intermediate between Europeans and Africans. A University of Tennessee study, found that "West African groups are more similar to one another than any other groups are to each other. The class means of the canonical variables were plotted and represent 64% of the among-group variation, Figure 6. The between canonical structure (Table 9) indicates that on the first canonical axis West Africans display more facial prognathism, wider nasal apertures, longer malars, and wider mid-facial breadth. Early American Whites display longer and wider vaults, wide biauricular breadth, larger values for cheek height, and larger values for occipital subtense. The second canonical axis is primarily separating groups based on vault height and frontal chord values. The 1600 and 1650 White half-century groups display the lowest vault heights and the 1700 and 1750 White half-century groups display the highest values for vault height. Based on the craniofacial variables used in the present analysis, the early American Black sample is intermediate to the West African and American White samples."
These findings are consistent with earlier literature:
Pollitizer (1958) found American Blacks morphologically and genetically intermediate between American Whites and West Africans based on quantitative polygenic traits and genetic data. However, Pollitizer's study uses recent American Black and White and West African samples. Trevor was interested in quantifying phenotypic traits of American Blacks by determining specific traits that were more similar to Africans and traits that were more similar to Europeans. In his analysis, he found three variables in American Blacks that were significantly higher than values for West African and British crania, indicating that American Blacks were not just intermediate, but displayed a unique morphology. These variables include facial height, nasal height, and orbital breadth. As other studies during this time period and earlier, the increased values for the three variables were attributed to admixture. In Angel's study of colonial to modern skeletal change in both American Blacks and Whites, he attributed an increase in facial height among American Blacks specifically to admixture with American Whites and Native Americans.
Per the University of Tennessee study, "[t]he most interesting relationship was found between SNPs and craniometrics, both indicating American Blacks to be intermediate between West Africans and American Whites. If craniofacial morphology was influenced by plasticity more than genetics, then the craniometric data would not "fit" well with the SNPs data. While plasticity does likely affect craniofacial morphology, the fit between the SNPs and craniometric data supports a genetic influence." Accordingly, the intermediacy of Black-Americans is supported both craniofacially and genetically. These findings are reinforced by a 2021 study published in Forensic Anthropology Volume 4, which found, "the [Black-American] group intermediate to the West and Central Africans and European Americans on the first axis."