Esterase D and carbonic anhydrase 2 in a natural population ofCebus apella from Brazil

A comparative study of eleven protein systems in tamarins, genus Saguinus (Platyrrhini, Callitrichinae)

The genetic variability of six tamarin taxa, genus Saguinus, was analyzed comparatively using protein data from eleven systems coded by 15 loci. S. fuscicollis weddelli and S. midas midas were the most polymorphic taxa, and S. bicolor the least. The results of the phylogenetic analyses (UPGMA and neighbor-joining) and the genetic distances between taxa were generally consistent with their geographic and probable phylogenetic relationships. Analyses of the S. bicolor and S. midas populations suggested that they represent no more than three subspecies of a single species, S. midas, with the bicolor forms belonging to a single subspecies, S. midas bicolor. If supported by additional studies, this would have important implications for the conservation of the bicolor form, which is endangered with extinction. The genetic similarity of S. fuscicollis and S. mystax was also consistent with their geographical and morphological proximity, although more data from a larger number of taxa will be required before the taxonomic relationships within the genus can be defined.

Divergence between biochemical and cytogenetic differences in three species of the Callicebus moloch group

Specimens from three species of the Callicebus moloch group--C. moloch (N = 80), C. brunneus (N = 166), and C. cupreus (N = 23)--were studied. Twenty genetic loci were investigated through electrophoresis, genetic distances were estimated, and the results compared with the available cytogenetic data. Low values of genetic distance were encountered, contrasting with relatively large chromosome differences. We propose that recent karyotypic rearrangements, rather than other Pleistocene events, were the major evolutionary mechanisms determining speciation in these three taxa.

Coat color and biochemical variation in Amazonian wild populations of Alouatta belzebul

A comparative study of 13 blood genetic systems and pelage color variation was performed in four wild populations of Alouatta belzebul. The animals from the west bank of the Tocantins River showed less color variation than those from the east bank, as well as less than those from Tocantins Island. The blood genetic markers, however, revealed an opposite pattern of variation. A previously undescribed morphological variant (completely red) was observed in one specimen of the east bank, where pelage color of the local population varied from completely black to completely red. Levels of heterozygosity and inter- and intralocus variances for the blood systems are compared with those observed in five other species of New World primates.