SOME EVOLUTIONARY TENDENCIES OF NEOTROPICAL PRIMATES: Algunas tendencias evolutivas de los primates neotropicales

the evolution of neotropical primates has occurred isolated from other primates of the world, resulting in a distinct evolutionary history. various characteristics of neotropical primates (platyrrhini) are quite distinct from those of the old world (catarrhini), including the dental formula, the position of cranial plates, the anatomy of the auditory apparatus, much less average body weights, much less terrestrial adaptation, prehensile tails for some, and conservative phenotypes. additionally monogamous forms of platyrrhini share a tendency for rapid chromosome evolution with one monogamous group of catarrhines (hylobatids or gibbons). the phyletic history of the platyrrhine monkeys seems to contrast with that of the catarrhine inasmuch as there was a very early division (miocene) of the new world monkeys into groups that exist today, whereas the appearance of old world primate family groups seemed to have occurred much more recently in the plio-pleistocene. some of these tendencies can be explained hypothetically, looking at ecological characteristics suggested for the new continent while other tendencies are perhaps the result of random evolutionary pathways taken during the course of evolution such as genetic drift and founder effect. nevertheless there is still much work to be done to be able to recognize the singularities of the platyrrines and to appreciate the details of their evolution.