The Physical Anthropology and Genetics of Marginal People of the Southeastern United StatesPosted in Anthropology, Articles, Tri-Racial Isolates, United States on 2010-12-01 01:34Z by Steven |
The Physical Anthropology and Genetics of Marginal People of the Southeastern United States
American Anthropologist
Volume 74, Issue 3 (June 1972)
pages 719–734
DOI: 10.1525/aa.1972.74.3.02a00360
William S. Pollitzer
University of North Carolina
Admixture of White, Negro, and Indian peoples of the Southeastern United States from colonial days on has led to some unique populations isolated by social status. In time they formed distinctive gene pools. On the basis of physical traits and serological factors, it has been possible to reconstruct the approximate genetic contribution of parental populations to the hybrid ones. Some inherited diseases have also been concentrated in these isolates. Both differential fertility and changing social factors may affect the future of these populations.
Over vast spans of time populations of mankind have evolved many physical differences. In accordance with well established genetic principles, they arose because mutations in the genes controlling such traits occurred at random but conferred upon the individuals selective advantages. Thus, heavy pigmentation of the skin may have been an advantage to those living in the extreme sunlight of the tropics. Some anthropologists believe that body form and facial features may similarly represent adaptations to extremes of temperature and humidity. Geographical barriers such as oceans and deserts serve to isolate populations and emphasize their distinctive characteristics, although gradients exist between the physical traits of related people. Man’s increasing capacity for food production, most notably in the neolithic era when the cultivation of crops and domestication of animals greatly increased his food resources, contributed to the growth of populations. Particular groups of people of similar appearance expanded in numbers and later in territory, giving the impression that the earth was populated with a few “races.” An earlier generation of anthropologists, searching for distinct types, classified all people on the basis of a few physical traits such as skin color, hair form, head shape or nose width. More modern students of mankind have recognized that there are indeed only clines or gradients in all of these traits and that mixture is a universal phenomenon.
Can we then speak of “races” of man at all? While the concept of fixed types remains in the popular thinking, many scientists have gone to the opposite extreme and denied the reality of race at all. My own position is an intermediate one in which I liken human populations to the surface of the earth. Here is a small elevation and, there, a larger one; here is a single contour and, there, a doubled one. Shallow valleys separate some high ground; deep valleys separate others. Who can say, then, what is to be labeled a hill and what is to be called a mountain? Shall we use one name or two names for closely related projections? Where we draw the line-what labels we attach-these are arbitrary decisions; but the rises and the falls in the earth’s surface are facts of nature. So it is with human populations. How finely we wish to divide them, how broadly we lump them or the designations we give to them will inevitably vary; but large populations with distinctive features are still recognizable. It is, of course, mating preferences for physical characteristics which govern the collection of genes in so-called gene pools; and it is our culture which determines these choices. In that sense, those physically recognized groupings which we may popularly refer to as “races” are dependent upon our culture both for their formation and for their definition…
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