Inca bone ( lat. Os Incae ) is a non-constant additional bone of the human skull , which is formed in some cases as a result of incomplete fusion of the upper scales of the occipital bone with the body of the occipital bone.
The bone was named on behalf of the South American Inca tribe. In Inca skull samples, this bone was present in approximately 20% of cases. In other human populations , the incidence of Inca bone does not exceed 10%. Its formation is associated with the following circumstances. The scales of the occipital bone are formed from four independent centers of ossification, which in the process of embryonic development in most cases merge without a trace between themselves and with the body of the occipital bone. In some cases, a noticeable seam remains between the scales (in these cases called the “Inca bone”) and the body of the occipital bone (the so-called mendous suture ). Occasionally, incomplete fusion of ossification centers in the rudiment of the scales of the occipital bone is observed, then the Inca bone itself breaks up into 2–4 fragments. It is believed that the Inca bone is homologous to the inter-dark bone ( Latin os interparietale ), which in the form of a separate bone is expressed normally in some mammals .
Literature
- Inca Bone // Basket - Kukunor. - M .: Soviet Encyclopedia, 1953. - P. 138. - ( Great Soviet Encyclopedia : [in 51 vols.] / Ch. Ed. B. A. Vvedensky ; 1949-1958, vol. 23).
- I. Ya. Roginsky, M. G. Levin. Basics of anthropology. Moscow, Publishing House of Moscow State University, 1955.S. 77-78.