82. Heredity
The first of the several factors through which it is logically possible to explain the life and conduct and customs of any people is race or heredity: in other words, the inborn tendencies, bodily and mental, of the people that carry these customs. At first sight it may seem that this element of race might be quite influential. Since peoples differ in inherited characteristics of body—complexion, features, hair, eye color, head form, and the like—these bodily inherited peculiarities ought to be accompanied by mentally inherited traits, such as greater or less inclination to courage, energy, power of abstract thought, mechanical ingenuity, musical or æsthetic proclivities, swift reactions, ability to concentrate, gift of expression. Such racial mental traits, again, might conceivably be expressed in the conduct and culture of each people. Races born to a greater activity of the mechanical faculties would achieve more or higher inventions, those innately gifted in the direction of music would develop more subtly melodious songs, and so on.
Yet in every particular case it is difficult or impossible to establish by incontrovertible evidence that heredity is the specific cause of this accomplishment, of this point of view, or of this mode of life; that it is the determining factor to such and such degree of such and such customs. This is not a denial of the probability that inborn racial differences exist. It is an affirmation of the difficulty, discussed in Chapters [I], [IV], and [V], of knowing what is inborn; and more specifically, of the difficulty of tracing particular customary activities back to particular racial qualities. The problem of connecting specific race traits with specific phenomena of culture or group conduct, such as settled life, architecture in stone, religious symbolism, and the like,—of determining how much of this type of architecture or symbolism is instinctive in the race and how much of it is the result of traditional or social influences,—remains unsolved.
For example, should one try to apply to the explanation of the mode of life or culture of the Indians of the Southwestern United States biological facts, such as their head form, one would be confronted by the difficulty that long heads are characteristic of some of the town-building tribes, or Pueblos, and also of some of the tribes living in brush huts. Broad heads are also found among both the settled and nomadic tribes. The Pueblo Taos and non-Pueblo Pima are narrow-headed, the Pueblo Zuñi and non-Pueblo Apache broad-headed. So with the pulse rate, which has been already mentioned (§ [70]) as unusually slow among the Southwestern Indians. It is the same for the nomadic Apache who lived by fighting, and for the Hopi and Zuñi who are famous for their timidity and gentleness. Similar cases might be cited almost endlessly. It is evident that they are of a kind with the lack of correspondence between race and speech, or race and nationality, among the European peoples.