A study of the degeneracy of the jaws of the human race / by Eugene S. Talbot.

  • Talbot, Eugene S. (Eugene Solomon), 1847-1924.
Date:
1892
Catalogue details

Licence: Public Domain Mark

Credit: A study of the degeneracy of the jaws of the human race / by Eugene S. Talbot. Source: Wellcome Collection.

Provider: This material has been provided by the University of Toronto, Harry A Abbott Dentistry Library, through the Medical Heritage Library. The original may be consulted at the Harry A Abbott Dentistry Library, University of Toronto.

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    where the face and special senses are located within a limited area upon the front of the head.'' The animal depends upon its physical strength for its food and for protection. The bony Iramework is very strong. The bones are large, long, and the prominences upon their surfaces for the attach- ment of muscles are very marked, thus indicating that the muscles are large and strong. As we ascend the scale to man, we find that the bones are smaller in diameter, and shorter, showing that the muscles are not so large and strong. Great changes take place in the jaws and teeth. They become smaller in size, the teeth change their shape, because man now is no longer required to procure his food with his teeth or to protect himself by his jaws. The brain is continually enlarging and changing its shape, and the bones of the head, especially the parietal and frontal, expand forward, laterally, and upward. The temporal muscle, zygomatic arch, and jaws de- crease in size and are not so prominent. If we compare the jaws of the orang and chimpanzee with that of a negro, we observe a wonderful difference as regards size, shape, and character of the teeth. If we will now compare the negro jaws with those of our working-classes, and these latter with the jaws of young people of the well-to-do class, who are not required to work physically, we shall observe almost as great a change as we noticed in the case of the orang and the negro. These changes are the result of the law of compensation. The tendency of the human race is to develop in an intellectual line, and if the race seeks a high education and brain-development, without a corresponding physical training, the result is a fully developed cerebrum and a weak physical structure. Our food is now prepared in such a manner that mastication is almost unnecessary, and arrest of development of the jaws and decay of the teeth must follow as a result. Comparing the shape of the face, head, and general make-up of the present people with those of our ancestors, there can be no question that the human race is improving in grace, beauty, and intellect. The changes which occur in the general outline of the head and jaws in a few generations, are excellently illustrated in the following portraits of a noted family in this country. Four generations are here shown, in the order in which they lived. The cuts are drawn from daguerreo- types and photographs, and of course are useful only in giving the general outlines of the shapes of the heads. Unfortunately, the hair upon the faces depicted in the last two illustrations forbids any comparison being made so far as the jaws are concerned. There is, however, such a contrast in the shapes of the heads that those who are familiar with craniology can readily trace the changes w^hich would naturally take place in the shapes of the jaws. Fig. I represents a man born in Connecticut in 1761 ; died in 1826. This picture represents a brachycephalic head with massive jaws, prominent lips, especially the upper. The nose is long', and the eyes are set close together ; the forehead very high and straight. Quite a change is noticeable in the second generation, depicted in Fig. 2. The face is not so long, the lateral diameter of the head is larger, the forehead more prominent, and the eyes are a little farther apart. The nose is about the same length, and while there is a general resemblance ab(>ut ^\\e moUth; and chin, the distance from the