Anthropol. Sci. 110(4),389-402, 2002 |
|||||
 |
|||||
| Shintaro Kondo1 and Masahito Natori2 |
|||||
|
|||||
| (Received
May 1, 2001; accepted June 12, 2002) |
|||||
| Abstract
The allometric relationship between the second
deciduous molar (dm2), the first permanent molar (M1), and body weight
was investigated in catarrhine primates, including fossil hominid taxa.
In this study, tooth and body weight measurements were compared in 14
species of hominoids and 11 species of cercopithecids. In all species,
the mesiodistal and buccolingual crown diameters of dm2 were smaller
than those of M1. The tooth crown area (mesiodistal crown diameter multiplied
by buccolingual crown diameter) was used as the measure of tooth size.
Allometric coefficients were computed as the slope of rectilinear functions
of the logarithmically transformed data. Allometric scaling of tooth
crown area to body weight showed isometry (the slopes ranged from 0.593
to 0.700). The allometric coefficients were slightly larger in M1 and
in dm2, and were larger in the mandible than in the maxilla, but these
differences were not significant. Both hominoids and cercopithecids
were close to the regression line in both dm2 and M1, but Australopithecus
species were perculiar that they have large permanent and deciduous
molars in comparison to body weight, with A. boisei having the largest
molars. These results indicated that the tooth crown size of dm2 scales
to body weight in the same pattern as in the M1. The allometric scaling
of the tooth crown area of dm2 to that of M1 showed negative allometry
in both the maxilla and mandible, but these slopes were nearly 1.000
(0.932 in the maxilla and 0.954 in the mandible). Both hominoids and
cercopithecids lay close to the regression line, indicating that the
size of dm2 is closely related to that of M1. Key Words: allometry, second deciduous molar, first molar, body weight, catarrhine primates |
|||||
| (C)Copyright
2002 The Anthropological Society of Nippon |
|||||
