A head's breadth as a percentage of its length. Heads of different relative breadths are termed brachycephalic (broad), mesocephalic (intermediate), and dolichocephalic (long). The cranial index expresses comparable ratios on the skull, rather than the living head. The notion is especially used in anthropological classification.
The cephalic index is the ratio of the maximum breadth of the head to its maximum length (i.e., in the horizontal plane, or front to back), sometimes multiplied by 100 for convenience. It was defined by Swedish professor of anatomy Anders Retzius (1796-1860) and first used in physical anthropology to classify ancient human remains found in Europe. In 2002 a paper by Sparks and Jantz re-evaluated some of Boas's original data using new statistical techniques and concluded that there was a "relatively high genetic component" of head shape.
In adults, the index is no longer used except for describing individuals' appearances, and has no correlation with behavior.
Technically the measured factors are defined as the maximum width of the bones that surround the head, above the supramastoid crest (behind the cheekbones), and the maximum length from the most easily noticed part of the glabella (between the eyebrows) to the most easily noticed point on the back part of the head. (Discuss)
The terminology is also applied to animals, such as dogs and cats.
List of brachycephalic (snub-nosed) dogs:
American Straffordshire Terrier Boston Terrier Boxer Brussels Griffon Bull Terrier Dutch Pug English Bulldog English Toy Spaniel French Bulldog Japanese Spaniel (Japanese Chin) Japanese Pug Pekingese Shih Tzu Shar-Pei Straffordshire Bull TerrierList of brachycephalic (snub-nosed) cats:
Himalayan cat Persian catDolichocephalic animals
It has been suggested that this section be split into a new article entitled Cephalic index (non-human). (Discuss)List of dolicocephalic canines:
Wolf Coyote Sighthounds such as Afghan Hound Azawakh Borzoi Greyhound Hortaya Borzaya Saluki Sloughi
User Comments Add a comment…