Crania of Mammals

We photographed many mammalian crania that were macerated in Japan and which were without their mandibles or hyoid bones. They were housed in 5 public and private institutions. We excluded severely fractured and very young bones. Nearly all the mammalian materials from DUSM were included in the first release in 2000. Thus, the number of specimens exceeded 50 for each of several species such as American minks, rhesus monkeys, crab-eating macaques, foxes, Japanese martens, raccoon-dogs, domestic dogs, and squirrel monkeys. In the current release, crania were chosen from the other four institutions listed in Table 1, concentrating mainly on species unavailable at DUSM. The total number of specimens photographed amounted to 1826. All mammalian skeletons from Tohoku University in Sendai, which had been macerated and prepared, mostly by Shigehara, were added. Monkeys and apes were selected from the collections of Primate Research Institute and Japan Monkey Centre in Inuyama, respectively. Rare mammalian species from the Institute for Live Fossils (a private laboratory of Tomoyuki Inaba) contributed much to increase the number of species, reaching 308.

Table 1. Number of crania photographed
Source of specimenNumber
Dokkyo University School of Medicine1301
School of Dentistry, Tohoku University196
Primate Research Institute, Kyoto University123
Japan Monkey Centre19
Institute for Live Fossils (Tomoyuki Inaba)186
Total1825

The numbers of orders, families, genera, and species contained in our mammalian database are summarized in Table 2, where a percentage shows the proportion of our final content to the total number in each taxonomic category.The numbers of families, genera, and species contained within the Order Primates are summarized in Table 3. It is noted that the primate species exceeded 50 % of the total, while the number of mammalian species photographed in our project represents only 7 % of the total in Table 2. This bias of bone selection arises from favoritism of primate skeletons due to our disciplines relevant to human evolution.

Table 2. Final content, total, and percentage at each mammalian taxonomic level.
The total numbers of taxa within the mammals are based on Corbet and Hill (1991).
ContentTotalProportion (%)
Order162080.0
Family6913252.3
Genus189105817.9
Species30742827.2
Individuals1825

Table 3. Final content, total, and percentage at each level within the Order Primates.
The total numbers of taxa within the primates are based on Corbet and Hill (1991).
ContentTotalProportion (%)
Family91275.0
Genus385865.5
Species9318151.4
Individuals704

In general, the scientific names and common names are based on Corbet and Hill (1991), while the taxonomy of Japanese mammals and their Japanese names are derived from Imaizumi (1988). For the other species not included in the above references, we consulted two Smithsonian Institute publications (Wilson and Cole, 2000; Wilson and Reeder, 1992). Domestic species are placed in independent categories, since they are different from their ancestors.


Back to Menu