Individual and sexual characteristics of the skull
Last reviewed: 23.04.2024
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Each skull has individual features. For the skull as a whole, certain shape, size, ratio of the size of the facial skull to the brain, the degree of development of the superciliary arches, mastoid processes, muscular tubercles, rough lines, etc. Are characteristic. These signs, as well as the size of the skull, are variable, but do not go beyond the conditional norm.
For individual characteristics of the shape of the skull (medullary) it is customary to determine its dimensions (diameters): longitudinal, transverse, high-altitude.
- Longitudinal dimension - the distance from the glabella to the most protruding point of the occiput is 167-193 mm (in males).
- The transverse dimension corresponding to the widest part of the skull is in the range from 123 to 153 mm.
- Vertical size - the distance from the middle of the anterior margin of the large (occipital) opening (basia) to the point of convergence of the sagittal suture with the coronal suture (bregma) is 126-143 mm.
The ratio of the longitudinal dimension (diameter) to the transverse dimension, multiplied by 100, is a cranial index (long-latitudinal index). With a cranial index value of up to 74.9, the skull is called long (dolichohrania); a pointer equal to 75.0-79.9, characterizes the average size of the skull (mesocrania), and with a pointer of 80 or more, the skull will be wide and short (brachycrania). The shape of the head corresponds to the shape of the skull. In connection with this, long-legged people (dolichocephaly), mid-annual (mesocaes) and broad- headed (brachycephaly) are distinguished .
Looking at the skull from above, one can see the variety of its shape: ellipsoid (with dolichobranium), ovoid (with mesocrania), spheroid (with brachycrania), etc. The capacity (volume of the cavity) of the cerebral cranium is also individual. It fluctuates in an adult from 1000 to 2000 cm 3.
The shape and size of individual bones of the skull and skull as a whole correspond in the process of their growth and development to the individual form of the brain, the sense organs and the initial parts of the digestive and respiratory systems fixed on its bones. This convincingly confirms the relief of the inner surface of the skull, reflecting the shape and development of the organs enclosed in it. For example, three cranial fossae of the inner base of the skull interfere with the corresponding parts of the brain. The relief of the inner surface of the skull reflects the location of the impressions of furrows and gyri, arterial and venous furrows,
The external shape of the skull largely depends on the development of the muscles, which have a modeling effect on young bone tissue. The absence of one or more chewing muscles on one side of the head entails asymmetry of the face and smoothing of finger-like impressions on the inner surface of the skull. Loss of the eye is accompanied by a decrease in the further almost complete infection of the orbit. This helps to increase and smooth the walls of the anterior cranial fossa on the corresponding side.
Sexual differences in the human skull are insignificant. Therefore, it is sometimes difficult to distinguish a male skull from a female one. At the same time, the male skull of tuberosity (the place of attachment of the muscles) is usually seen better; stronger protrude the occiput, the superciliary arches. Glaznitsy are relatively large, the paranasal sinuses are better expressed. The bones are usually somewhat thicker than the female skull. The longitudinal (anteroposterior) and vertical dimensions of the male skull are large. The male skull is more spacious (150-200 cm 3 ) than the female skull . The capacity of the skull in men is about 1450 cm 3, and in women - 1300 cm 3. The difference can be explained by the smaller size of the woman's body.
The shape of the skull does not affect a person's mental abilities. Attempts by some falsifiers of science based on the shape of the skull to speak of "higher" and "lower" races are untenable. This is evidenced by approximately the same size of the skull in representatives of different races. Thus, for example, the longitudinal size of the male skull in representatives of the Caucasoid type is on the average 180.7 mm, in the Mongoloid type 184.6 mm, in the Negroid type, 185.2 mm. According to anthropologists, Sioux Indians have high head sizes, and the capacity of the skull for South African blacks (1540 cm 3 ) is larger than that of many Europeans (Ya. Ya. Roginsky, MG Levin). VV Ginzburg (1963) cites figures for the skull capacity of Australians (1347 cm 3 ), Dutch (1382 cm 3 ), Swiss (1367 cm 3 ), Buryat (1496 cm 3 ), Eskimos (1563 cm 3 ). In different races, there are large skull sizes, and small ones.
Numerous studies of anthropologists have not established any grounds for believing that the size of the cerebral skull predominates in one or another race. The somewhat smaller head sizes of Bushmen, Pygmies, and others are explained by their small growth. Often, a reduction in the size of the head may be the result of inadequate nutrition for centuries and other unfavorable living conditions (Ya. Ya. Roginsky, MG Levin). Judgments about the allegedly unequal order of occlusion of the skull joints in representatives of various races are also untenable.
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