How race becomes biology: Embodiment of social inequality

Posted in Anthropology, Articles, Health/Medicine/Genetics, Media Archive, Politics/Public Policy, Social Science on 2011-04-26 21:39Z by Steven

How race becomes biology: Embodiment of social inequality

American Journal of Physical Anthropology
Special Issue: Race Reconciled: How Biological Anthropologists View Human Variation
Volume 139, Issue 1 (May 2009)
pages 47–57
DOI: 10.1002/ajpa.20983

Clarence C. Gravlee, Associate Professor of Anthropology
University of Florida, Gainesville

The current debate over racial inequalities in health is arguably the most important venue for advancing both scientific and public understanding of race, racism, and human biological variation. In the United States and elsewhere, there are well-defined inequalities between racially defined groups for a range of biological outcomes—cardiovascular disease, diabetes, stroke, certain cancers, low birth weight, preterm delivery, and others. Among biomedical researchers, these patterns are often taken as evidence of fundamental genetic differences between alleged races. However, a growing body of evidence establishes the primacy of social inequalities in the origin and persistence of racial health disparities. Here, I summarize this evidence and argue that the debate over racial inequalities in health presents an opportunity to refine the critique of race in three ways: 1) to reiterate why the race concept is inconsistent with patterns of global human genetic diversity; 2) to refocus attention on the complex, environmental influences on human biology at multiple levels of analysis and across the lifecourse; and 3) to revise the claim that race is a cultural construct and expand research on the sociocultural reality of race and racism. Drawing on recent developments in neighboring disciplines, I present a model for explaining how racial inequality becomes embodied—literally—in the biological well-being of racialized groups and individuals. This model requires a shift in the way we articulate the critique of race as bad biology.

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Admixture in a biologically African caste of Black Americans

Posted in Anthropology, Articles, Media Archive, United States on 2011-01-25 04:37Z by Steven

Admixture in a biologically African caste of Black Americans

American Journal of Physical Anthropology
Volume 74, Issue 2 (October 1987)
pages 265–273
DOI: 10.1002/ajpa.1330740213

Curtis W. Wienker, Emeritus Professor of Anthropology
University of South Florida

Social and historical factors account for much of the variation in European ancestry among different Black American populations, including that of McNary, Arizona. The Black population of McNary is socioculturally and geographically isolated. Admixture estimates based upon reflectometry and serological data suggest that this population has less than 5% European ancestry. Anthropometric and hemoglobin data also suggest that this population is more African in ancestry than other Black American populations. Admixture estimates for the population are complicated by several factors. Genetic drift has probably affected Black McNary; estimated effective population size (Ne) is 52.11 and the coefficient of breeding isolation is less than 50. Frequencies of the alleles B, O, and r support this hypothesis; they are quite atypical for a Black American group. Selective migration and occupational selection may also have influenced the current genetic composition of Black McNary. Over 80% of the Black residents of McNary were born in backwoods lumbering towns in the American South. Most Black families in McNary trace their economic reliance on lumbering back several generations. Historical sources and demographic data from Black McNary suggest that Southern Black millworking families formed an endogamous unit that produced this caste, which has a relatively small amount of European ancestry.

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Brief communication: Admixture analysis with forensic microsatellites in Minas Gerais, Brazil: The ongoing evolution of the capital and of an African-derived community

Posted in Anthropology, Articles, Brazil, Caribbean/Latin America, Media Archive on 2011-01-25 01:32Z by Steven

Brief communication: Admixture analysis with forensic microsatellites in Minas Gerais, Brazil: The ongoing evolution of the capital and of an African-derived community

American Journal of Physical Anthropology
Volume 139, Issue 4 (August 2009)
pages 591–595
DOI: 10.1002/ajpa.21046

Marília O. Scliar
Departamento de Biologia Geral, ICB
Universidade Federal de Minas Gerais, MG, Brazil

Marco T. Vaintraub
GENETICENTER—Centro de Genética e Reprodução, Nova Lima, MG, Brazil

Patrícia M.V. Vaintraub
GENETICENTER—Centro de Genética e Reprodução, Nova Lima, MG, Brazil

Cleusa G. Fonseca
Departamento de Biologia Geral, ICB
Universidade Federal de Minas Gerais, MG, Brazil

We report the estimated allele frequencies for 13 and 14 microsatellite loci in two populations of Minas Gerais, Brazil as follows: Belo Horizonte (the capital) and Marinhos (an African-derived community). Analysis of the African, Amerindian, and European genetic contributions to both populations, together with historical information, revealed distinct differences between the two populations. Estimates for Belo Horizonte revealed a higher-European (66%) than African (32%) contribution, and a minimal Amerindian contribution. These results are consistent with the peopling of the city mainly by people from the Minas Gerais hinterland, a people highly admixed but with more European ancestry. Estimates for Marinhos confirmed the high-African component of the population. However, a temporal analysis of two datasets—CURRENT (representing the population living in Marinhos today) and ORIGINAL (representing families, who have lived in Marinhos since the onset of the 20th century),—identified a diminishing of the population’s African ancestry from 92% in the ORIGINAL group to 67% in the CURRENT group. This change is here interpreted as a consequence of the growing migration into the village of people with more European ancestry and subsequent admixture with the local population.

Description of the supporting document:

Supporting Table S1. Origin and size of parental sample populations used in admixture analyses. Supporting Table S2. Allele frequencies distribution of 13 STRs loci in Belo Horizonte population. Supporting Table S3. Allele frequencies distribution of 14 STRs loci in Marinhos (CURR) population. Supporting Table S4. Allele frequencies distribution of 14 STRs loci in Marinhos (ORIG) population. Supporting Table S5. Admixture proportions and 90% confidence intervals for each individual of Marinhos population obtained with the Structure 2.0 program.

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Notes on physical anthropology of Australian aborigines and black-white hybrids

Posted in Anthropology, Articles, Media Archive, Oceania on 2011-01-24 01:28Z by Steven

Notes on physical anthropology of Australian aborigines and black-white hybrids

American Journal of Physical Anthropology
Volume 8, Issue 1 (January/March 1925)
pages 73–94
DOI: 10.1002/ajpa.1330080105

Charles B. Davenport, Director
Department of Experimental Evolution
(Carnegie Institution of Washington)
Cold Spring Harbor, Long Island, New York

Introduction

In September 1914, after the meetings of the British Association in Australia, I was given transportation by the Government of New South Wales, enabling me to go to the government reservation for aborigines at Brewarrina on the Burke division of the State railroad. This reservation is on the Barwon fork of the Darling River, about 60 miles south of the Queensland boundary.  The purpose of the visit was to observe near by a number of  individuals of the fast disappearing race.

While at Brewarrina, during about six days, I enjoyed the hospitality of Mr. and Mrs. Arnold’s tact and good judgment that I was enabled to see as many of the inhabitants of the Station as time permitted and to make some simple measurements upon them…

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The Cajuns of Southern Alabama: Morphology and Serology

Posted in Anthropology, Articles, Media Archive, Tri-Racial Isolates, United States on 2010-12-30 03:04Z by Steven

The Cajuns of Southern Alabama: Morphology and Serology

American Journal of Physical Anthropology
Volume 47, Issue 1 (July 1977)
pages 1-6
DOI: 10.1002/ajpa.1330470103

William S. Pollitzer
University of North Carolina, Chapel Hill

Kadambari K. Namboodiri
University of North Carolina, Chapel Hill

William H. Coleman
University of Alabama, Huntsville

Wayne H. Finley
University of Alabama, Birmingham

Webster C. Leyshon
Laboratory of Developmental Biology and Anomalies
National Institute of Dental Research, Bethesda, Maryland

Gary C. Jennings
University of Florida, Gainesville

William H. Brown
University of North Carolina, Chapel Hill

A survey was conducted of 324 members of the Cajun isolate of Southern Alabama. Tradition and appearance suggest that this population of about 3,000 are not entirely White, Black, or Indian but constitute a triracial community somewhat reproductively isolated and inbred. The earliest American settlement in the area, along the banks of the Mobile and Tombigbee Rivers, lay between Spaniards to the South and Indian tribes on the other sides: Creek, Choctaw, and Cherokee.

Physical measurements are reported for 71 adults, plus color of skin, eyes, and hair. X-rays were taken of wrist and ankle bones of some 253 children. Red blood samples were typed on adults and children, and haptoglobin, Gm, and Gc types were determined from serum. History and physical examinations were also made.

Physical measurements and observations suggest predominantly White ancestry, and D2 analysis confirms this, with least similarity to Indians. Analysis of serological traits implies almost 70% White, almost 30% Black, and very little Indians genes. Few defects of clear genetic etiology were discovered. Growth patterns judged from X-rays appeared normal. All genetic loci testable were in Hardy-Weinberg equilibrium except Gc. While history and some common surnames suggest endogamy in the past, the medical and serological findings, plus some additional surnames, indicate that the isolate has already been largely diluted or dissolved.

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Gene admixture in human populations: Models and predictions

Posted in Anthropology, Health/Medicine/Genetics, Media Archive on 2010-11-22 02:12Z by Steven

Gene admixture in human populations: Models and predictions

American Journal of Physical Anthropology
Volume 29, Issue Supplement S7 (1986)
pages 1–43
DOI: 10.1002/ajpa.1330290502

Ranajit Chakraborty, Robert A. Kehoe Professor and Director of Center for Genome Information
University of Cincinnati

Brief accounts of methods for estimating proportions of admixture in populations and individuals of hybrid origin are presented with the objective of appraising their underlying assumptions. In view of the uncertainties introduced by assumptions under which admixture estimates are obtained, it is concluded that the reliability of estimates derived from different methods cannot be formally compared. With examples from several admixed populations, it is shown that all methods do not necessarily give discordant results when identical data are used to obtain admixture estimates.

Even though past experiences using admixed populations to detect selection or to understand disease etiology have not been very successful, it is believed that admixed human populations can be regarded as a natural experiment. Hence, they are suitable for microevolutionary and epidemiological studies.

The proper identification of ancestral populations and the degree of asymmetry in gene flow (sex-biased admixture) are important issues in admixture studies. These aspects can be examined in the statistical properties of allele frequency distributions, but corroboration of particular models should be made from in-depth investigations of historical demography and social structure of admixed populations.

Future studies of admixture with DNA polymorphism data may resolve some of the uncertainties associated with current techniques of detecting genetic polymorphisms. Because of the abundance of genetic data, it is argued that morphological traits are of limited use in resolving current problems of human admixture studies.

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Blood groups of Whites, Negroes and Mulattoes from the State of Maranhão, Brazil

Posted in Anthropology, Articles, Brazil, Caribbean/Latin America, Media Archive on 2010-11-13 02:45Z by Steven

Blood groups of Whites, Negroes and Mulattoes from the State of Maranhão, Brazil

American Journal of Physical Anthropology
Volume 6, Issue 4
(December 1948)
pages 423–428
DOI: 10.1002/ajpa.1330060412

E. M. da Silva
Department of Hematology
Instituto Oswaldo Cruz, Rio de Janeiro, Brazil

Within the Brazilian “melting pot” the intensity and variation of the racial mixture rises to a high point in the State of Maranhão. Of the three main races entering into this mixture, Indian, Negro and White, remnants are still to be found in more or less pure condition. As would be expected, however, all possible combinations of these primary groups are now abundantly present. Thus the population of this State presents unlimited opportunities for research in the problems of physical anthropology growing out of race mixture.

The present study deals with the classical blood groups in Whites and Negroes and in mixtures of these two races. The observations were made in the city of São Luiz and in the village of Santo Antonio dos Pretos (Municipe of Codó), a little over 300 km southeast of the former.

The Negroes were selected on the basis of their well-known physical characteristics. The series totals 198 and includes representatives of different African groups.

The Whites are mainly from Arabian (Syrian) stock, with some Portuguese and a few Spanish individuals. The series totals 196.

The individuals of mixed origin, which we will call Mulattoes in accordance with Brazilian custom, are mostly if not all first generation crosses. Selection was made by examining…

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The Physical Form of Mississippi Negroes

Posted in Anthropology, Articles, Media Archive, Mississippi, United States on 2010-11-12 23:03Z by Steven

The Physical Form of Mississippi Negroes

American Journal of Physical Anthropology
Volume 16, Issue 2
(October/December 1931)
pages 193–201
DOI: 10.1002/ajpa.1330160213

Melville J. Herskovits (1895-1963), Professor of Anthropology and African Studies
Northwestern University

Vivian K. Cameron

Harriet Smith

During the years 1923 to 1927, research was carried on in an attempt to investigate the physical form of the American Negro, with particular reference to the question of a possible physical type being formed in the United States, and to the amount and consequences of the racial mixture that had gone into the formation of the Negro population of this country.  The results of this research may be briefly summarized as follows: first, that the American Negro, as indicated by the genealogies collected in the course of the study, represented much more racial crossing than had been generally recognized, and secondly, that in spite of this crossing, a physical type which combined the characteristics of the African and European ancestral populations hand which was relatively homogeneous in character had been formed.

Awaiting publication of the complete results of this study, a volume outlining the results was brought out. The point most generally made when this work was criticized was that since the majority of the sample utilized in the study had been measured in the north, the group studied could not be…

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The Variability of Hybrid Populations

Posted in Anthropology, Articles, Media Archive on 2010-11-03 18:59Z by Steven

The Variability of Hybrid Populations

American Journal of Physical Anthropology
Volume 16, Issue 3
(January/March 1932)
pages 283–307
DOI: 10.1002/ajpa.1330160312

K. Wagner
Department of Anatomy
University of Oslo

On the assumption of mendelian inheritance it should be expected that hybrid populations, apart from the first generation of crossing, must show an increased variability as compared with the original ‘races’ that entered into the mixture. Assuming that the characters investigated are genetically very complex, i.e., that there is pronounced polymeria, the difference in variability between hybrid populations and the relatively ‘pure’ races would no doubt be diminished, but not entirely eliminated. The chances for segregation of a polymeric character are, it is true, very small and diminish greatly with an increasing number of fundamental factors, so that a very large body of hybrid material would be required in order to be able to count upon a variation effect, but polymeric characters in this absolute sense are certainly exceptional. If the complete emergence of a character is due to combinations of the factors abc, then ab, ac, or be will in many, perhaps in most, cases have some, effect. Neither does dominance play any decisive role for the variability rule here laid down, as the segregation of recessive types must bring about a considerable increase in the variability of hybrid populations, and, quite apart from this, it may be said that absolute dominance hardly comes into consideration as regards most of the anthropological characters.

Here, as so often elsewhere, changes of environment may have a disturbing influence, but these must necessarily be disregarded in a theoretical consideration of the matter. In case the racial crossing took place far back in time, it might be imagined that the high degree of heterozygosis occasioned…

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Biological and Social Consequences of Race-Crossing

Posted in Anthropology, Articles, Health/Medicine/Genetics, Media Archive, Social Science on 2010-08-10 00:43Z by Steven

Biological and Social Consequences of Race-Crossing

American Journal of Physical Anthropology
Volume 9, Issue 2 (April/June 1926)
pages 145–156
DOI: 10.1002/ajpa.1330090212

W. E. Castle (1867-1962)
Bussey Institution, Harvard University

What constitute the essential differences between human races seems to be a question difficult for anthropologists to agree upon but from a biologist’s point of view those appear to be on safe ground who base racial distinctions on easily recognizable and measurable differences perpetuated by heredity irrespective of the environment.  See Hooton, 1926.  It is still a moot question how races originate, not merely in man, but also among lower animals and plants.  At one time natural selection was thought to be an all-sufficient explanation of the matter, but the more carefully the question is studied and the more exact and experimental in character the data which enter into its solution, the more fully we become convinced that forms of life are rarely static, that organic is the rule rather than the exception. Change is inevitable and is not limited to useful or adaptive variations.  Natural selection undoubtedly determines the survival of decidedly useful variations, which arise for any reason, and also the extinction of those which are positively harmful, but a host of there variations fall in neither of these categories and survive among the descendants as a matter of course, quite unaffected by natural selection.

The experimental study of evolution indicates that genetic (hereditary) variations are all the time arising, and with especial frequency in such organism are bisexual and cross-fertilized.

In a state of nature no species can long be separated by geographical barriers into  non-interbreeding groups, without the origins of specific or racial differences between such groups…

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