Marmoset evolution: the molecular evidence.

We report here the results of comparative immunological and electrophoretic studies of the serum proteins of the New World monkeys. Specifically, we find that the New World monkeys share a long period of common ancestry with the Catarrhini and that the divergence between these two groups occurred some 35-40 million years ago. The extant New World monkey lineages are then seen as sharing a long period of common ancestry subsequent to that divergence, with their radiation beginning in the early Miocene. We see seven distinct lineages stemming from this radiation: (1) Aotus, (2) Callicebus, (3) Cebus, (4) Saimiri, (5) Ateles-Lagothrix-Alouatta, (6) Pithecia-Cacajao and (7) Callimico-Callimico with Cebuella-Saguinus-Leontideus. Within those Ateles with Lagonthrix, and Callimico with Callithrix-Cebuella form further subgroups. The marmoset radiation appears to have begun some 7-10 million years ago.