Resumo:
The Karyotypes of the Brazilian marmosets C. jacchus and C. penicillafa
are very similar. Both have 2n = 46. C. jacchus has one more metacentric
pair and C. penicillata has one more submetacentric pair, while
the sex chromosomes show distinct morphological differences.
On the basis of the chomosome complement of these species some
considerations about the process ofchromosomal evolution are presented.
A short comparative study of these and other species of the same
genus shows that basic mechanisms such as centric fusion and pericentric
inversions can explain the observed morphologic chromosomal variations.
