Abstract
Dental variation among Callithrix species was analyzed. Based on Q-mode correlation coefficients and principal component analysis, Callithri argentata-C. humeralifer and C. aurita-C. geoffroyi-C. kuhli-C. penicillata-C. jacchus are grouped into one cluster, respectively. On the scattergrams based on the shape factor, the members of the latter cluster (C. jacchus group) make a line of C. aurita-C. geoffroyi-C. kuhli-C. penicillata-C. jacchus. Roughly speaking, their distribution areas are arranged in the order named from south to north. Fossil evidence shows that C. aurita has the most primitive feature of the C. jacchus group in proportion of the dentition. When combined with this knowledge, the morphological relationships of the C. jacchus group seem to be consistent with the step-by-step differentiation of the dental shape from southern species to northern one.
