The mind of primitive man

by Franz Boas

The whole trend of the studies of growth thus emphasizes the importance of the effect of rate of development upon the final form of the body. Illness in early childhood, malnutrition, lack of fresh air and physical exercise, are so many retarding causes, which bring it about that the growing individual of a certain age is in its physiological development younger than the healthy, well-nourished individual, who has plenty of fresh air, and who puts his muscular system to good use. Retardation or acceleration has, however, the effect of modifying the later course of development; so that the final stage will be the more favorable, the less the retarding causes.

It seems more than likely, judging from the course of development of a few simple mental activities that have been made the subject of study, that mental development follows laws quite analogous to those of physical development (Meumann).

These facts relating to growth are of fundamental importance for a correct interpretation of the oft-discussed phenomena of early arrest of growth. We have seen that among members of the same race a prolonged period of growth goes hand in hand with unfavorable development, while an abbreviated period of growth results in larger dimensions of all physical measurements, and in a superiority of mental activity. In this statement pathological cases of complete premature arrest of development, or of over-development, are of course excluded,—cases of dwarfish growth or of microcephaly, as well as cases of hypertrophic growth of organs. It follows, that, in judging the physiological value of arrest of growth, the mere fact that growth ceases in one race at an earlier time than in another cannot be considered as significant in itself without observations on the rapidity of growth.

So far, the question still remains open, in how far there may be changes in the types of man that cannot be explained by acceleration or retardation of growth.

An attempt has been made by Rieger to explain differences in head-form as due to the effect of physiological and mechanical conditions, and Engel emphasizes the effect of pressure of the muscles upon the forms of the head. Walcher tries to explain different head-forms by the consideration of the position of the infant in the cradle. He believes that position on the back produces round heads; position on the side, long heads. It would seem, however, that the difference of head-form in large areas of Europe, in which infants are treated in the same manner, are too great to make this explanation acceptable.

A number of observations have been made, however, which demonstrate conclusively a difference between urban and rural types. These observations were first made by Ammon, who showed that the urban population in Baden differs from the rural population in head-form, stature, and pigmentation. He accepts the conclusion that we have here an actual change in type; due, however, not to a direct effect of environment, but rather to an elimination of certain types in city life: in other words, an effect of natural selection. This observation is in accord with observations made by Livi in the cities of Italy, which show also a difference when compared to the surrounding country. Comparisons of the normal and hospital populations of London, made by Shrubsall, are not unfavorable to the assumption of a certain amount of correlation between morbidity and physical type, although the homogeneity of material from a metropolis like London, drawn from different social strata of a large city, remains always open to doubt.

Another explanation, given by Livi, seems to account adequately for the difference between city and country population, without necessitating the assumption of any considerable effect of natural selection, which presupposes an improbable correlation between mortality and fertility on the one hand, and traits like head-form and pigmentation on the other. The change of type in cities, so far as it has been observed, is of such character, that the city always shows greater resemblance to the average type of the whole large district in which it is located. If the local rural population is markedly short-headed, the general type over a larger area from which the city population is drawn more long-headed, then the city population will be more long-headed, and vice versâ. Unless selection can be demonstrated to occur in a sufficient number of definite families, this explanation seems simpler and adequate.

Up to quite recent times no evidence of actual changes of type was available, except the observations by Ammon and those by Livi on the physical characteristics of rural and urban populations, to which I have just referred, and some others on the influence of altitude upon physical form. In the discussions of the distribution of different types of man in Europe, peculiarities of body-form in certain areas—as in the mountains of central France, in parts of Tuscany, in the province of Zealand in Holland, in southwestern Norway—have been explained as due to the survival of old racial types, to the influence of natural selection, or to the direct influence of environment, according as the necessities of the case prompted the investigator to adduce the one cause or the other, or a combination of any two or of all, as a convenient explanation of the difficult phenomenon (Ripley). It goes without saying that haphazard application of unproved though possible theories cannot serve as proof of the effectiveness of selection or of environment in modifying types. The effectiveness of selection can be proved only by an investigation of the surviving members of a type as compared to those eliminated by death, or of a shifting of population connected with the selection of a certain type. The influence of environment requires the direct comparison of parents living under one environment with children living under another environment.

I cannot give any example in which the influence of selection has been proved beyond cavil. It seems plausible that in the criminal colonies of earlier periods, and in the settling of the West by the most vigorous members of our Eastern population, and in the complementary weeding-out of strong elements in some parts of New England, this principle may have been active; but we have no actual data which would connect with physical types the selection that has undoubtedly taken place.

On the other hand, it has been my good fortune to be able to demonstrate the existence of a direct influence of environment upon the bodily form of man by a comparison of immigrants born in Europe and their descendants born in New York City (Boas). I have investigated four groups of people,—the South Italians, representing the Mediterranean type of Europe, which is characterized by short stature, elongated head, dark complexion and hair; the Central European type, which is characterized by medium stature, short head, light hair and lighter complexion; the Northwest European type, which is characterized by tall stature, elongated head, light complexion, and blond hair. Furthermore, I have investigated an extended series of East European Hebrews, who resemble in some respects the Central European group. The traits which I selected for examination are head-measurements, stature, weight, and hair-color. Among these, only stature and weight are closely related to the rate of growth, while head-measurements and hair-color are only slightly subjected to these influences. Differences in hair-color and head-development do not belong to the group of measurements of which I spoke before, which depend in their final values upon the physiological conditions during the period of growth. From all we know, they are primarily dependent upon heredity.