By anthropology of the Old Americans is meant the status, physically, physiologically and demographically, of the oldest parts of the white population of the United States, as contrasted with the American population at large and with other units of the white race.
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In order to supply as far as possible the need in these directions the writer undertook, in 1912, a systematic anthropological study of the oldest part of the "Old Americans." By "Old Americans" he designated all those who in their families had no mixture with more recent elements on either side for at least three generations. The study lasted until the present year. It was carried on in the anthropological laboratory of the U. S. National Museum, but eventually also in the field, and the utmost care was exercised throughout to assure the reliability of the data secured.
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The above data on the eyes and hair permit the formulation of the following conclusions regarding pigmentation, and the other conditions here studied, in the Old Americans :
SKIN. 1. Two-thirds of the old stock males and three-fourths of the females show skin that may be classed as medium.
2. In only 5 per thousand in males, but in 52 per thousand in the females, is the skin plainly lighter than the medium. All of these cases are associated with pure light eyes and light or red hair.
3. In a little over one-fourth of the males and in one-sixth of the females the skin is perceptibly darker than medium. Such skin is generally associated with brown eyes and medium to dark hair.
HAIR. 1. Only 1 among 16 males and 1 among 14.5 females has real blond hair.
2. One-half of the males and over four-tenths of the females show medium (or "medium brown") hair.
3. In one-fourth of the males and three-tenths of the females the hair is dark ("dark brown"), to near black.
4. In approximately 1 percent in the males and but a little more in the females the hair is fully black.
5. In 2.6 per hundred of males and 4.9 per hundred in females the hair is red or near red.
6. The females show a slight to moderate excess of true blonds (especially golden and yellow), but also of darks, blacks and reds, over the males.
7. There are some areas in which hair pigmentation among the Old Americans, due to isolation and more thorough mixtures, differs from that of the group as a whole.
8. Differences between the "Yankees" and the "Southerners" in this respect are only moderate, the former showing somewhat more lights, less darks, few if any true blacks and less reds. But the southerners show almost identical conditions in regard to hair pigmentation as those of the central states and those of mixed-state ancestry.
EYES. 1. Approximately one-third of the eyes of the males and one-fourth of the eyes of the females of the Old Americans are pure lights.
2. One-sixth of the males and one-fifth of the females show eyes the iris of which is pure brown (light, medium or dark) .
3. Over one-half of the males as well as females have eyes that show plain traces of brown in light (mixed).
4. There are on the whole more light and less dark eyes than there is of light and dark hair.
5. Regional differences are less marked than with the hair, except in isolated localities.
6. There is a considerable but not a complete correlation between the pigmentation of the eyes and that of the hair. Light eyes may in some instances be associated with dark (though not black) hair; but medium to dark eyes are as a rule accompanied by medium, dark or black hair.
BLONDS AND BRUNETS. 1. The classification of the Old Americans on the basis of both the color of the eyes and hair brings a number of the conditions relating to pigmentation out with special clearness.
2. Over one-half of the males and nearly one-half of the females are " intermediates."
3. Blonds are scarce, as are also true brunets, but the latter are plainly more frequent, especially in the females.
4. The females show slightly more blondes, more brunettes and less intermediates than the males.
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COMPARISONS. Suitable data for comparison are scarce. From what is available it appears that the pigmentation of both hair and eyes in the Old Americans is much like that of the present population of Great Britain, though the latter appears to show some excess of both dark eyes and dark hair.
As to changes with time, it seems probable that in both Great Britain and the United States there is taking place a slow progress towards a darker pigmentation of both eyes and hair, though the fact needs definite confirmation.
[Hrdlicka A. 1922. Physical Anthropology of the Old Americans. American Journal of Physical Anthropology 5(2):97-142.]