Allometric Variation of the Postcranial Skeleton in two South American Tamarins Saguinus oedipus oedipus and Saguinus fuscicollis illigeri (CALLITRICHIDAE, PRIMATES)

This research examines several aspects of allometry in the postcranial skeleton of two South American tamarins Saguinus oedipus oedipus and Saguinus fuscicollis illigeri. The statistical method used for analyzing these groups is reduced major axis regression. Bivariate plots are used to qualitatively evaluate group differences, particularly in regard to differing locomotor behavior. The allometric variation in the postcrania of these two species is described. Finally, allometric comparisons between these groups are made.

Heterochronic terminology is used to describe the allometric patterning. The most important result of this study is that geometric similarity was determined to exist between the groups. The comparisons support the contention that Saguinus oedipus oedipus is, in allometric terms, a geometrically "overgrown" Saguinus fuscicollis illigeri. Analysis of the bivariate plots reveal that significant differences in slope values between the species examined may be related to the documented anatomical locomotor variability exhibited by S.o.oedipus and S.f.illigeri.