Sistemática, evolución y paleobiogeografía de los primates Platyrrhini

Abstract

Estudios recientes acerca de las relaciones filogenéticas entre los primates platirrinos basados en datos morfológicos y moleculares, concuerdan en una división en tres familias: Atelidae, Pitheciidae y Cebidae, con la única excepción de Aotus, que dependiendo de enfoques moleculares o morfológicos, lo relacionan con cébidos o pitécidos, respectivamente. El registro fósil de los platirrinos procede de regiones distantes entre sí, siendo los más antiguos los que proceden del Oligoceno tardío de Bolivia (26 Ma). Estratos del Mioceno medio de La Venta, Colombia, y del Mioceno temprano a medio de Patagonia y Chile, se cuentan entre los yacimientos con mayor abundancia de platirrinos fósiles, representados por 11 géneros en La Venta, ocho en Argentina y uno en Chile, en un rango temporal desde aproximadamente 12 a 20 Ma, siendo más antiguos los de Patagonia y Chile. Los de La Venta son los más relacionados con formas actuales. Se recuperaron, además, dos géneros del Pleistoceno del este de Brasil, al menos tres taxones del Mioceno tardío de Río Acre, Brasil, y cuatro géneros del Pleistoceno y Holoceno de las Antillas. Estimaciones recientes sobre tiempos de divergencia en la filogenia de primates, sugieren una antigüedad para el crown group Platyrrhini que permite incluir a los primates patagónicos. Otro escenario que apoya una continuidad evolutiva entre las formas australes y las de estirpe amazónica, es un posible corredor paleobiogeográfico occidental sudamericano, considerando que para esos tiempos la cordillera de los Andes no representó una barrera significativa para la dispersión de los primates. Palabras clave: primates, Platyrrhini, sistemática, evolución, paleobioeografía. ABSTRACT. Recent studies on the phylogenetic relationships among the platyrrhine primates based on morphological and molecular data, agree in a taxonomic arrangement of three families: Atelidae, Pitheciidae, and Cebidae, with the only exception of Aotus, alternatively related to cebids or pitheciids depending on molecular or morphological approaches, respectively. The platyrrhine fossil record come from widespread regions, being the oldest the late Oligocene fossils from Bolivia (26 Ma). Fossiliferous strata ranging from the Middle Miocene of La Venta, Colombia, to the early and middle Miocene from Patagonia and Chile are among the richest in producing fossil platyrrhines, represented by 11 genera from La Venta, 8 genera from Argentina, and one genus from Chile. These records come from a temporal span between approximately 12-20 Ma, being the oldest those from Patagonia and Chile. La Venta primates are closest to the extant forms. Two additional genera from the Pleistocene of Brazil have been also recovered, as well as three taxa from the late Miocene of Río Acre, Brazil, and four from the Pleistocene and Holocene of the Greater Antilles. Recent estimations on divergence times of the primate phylogeny suggest an age for the crown group Platyrrhini that allows the inclusion of the Patagonian fossil primates. Another scenario supporting the evolutionary continuity between the Patagonian and Amazonian lineages is a possible paleobiogeographic corridor throughout western South America, considering that by that time the Andean cordillera did not represent a significant geographic barrier to avoid the primate dispersal.

Recent studies on the phylogenetic relationships among the platyrrhine primates based on morphological and molecular data, agree in a taxonomic arrangement of three families: Atelidae, Pitheciidae, and Cebidae, with the only exception of Aotus, alternatively related to cebids or pitheciids depending on molecular or morphological approaches, respectively. The platyrrhine fossil record comes from widespread regions, being the oldest the late Oligocene fossils from Bolivia (26 Ma). Fossiliferous strata ranging from the middle Miocene of La Venta, Colombia, to the early and middle Miocene from Patagonia and Chile are among the richest in producing fossil platyrrhines, represented by 11 genera from La Venta, 8 genera from Argentina, and one genus from Chile. These records come from a temporal span between approximately 12-20 Ma, being the oldest those from Patagonia and Chile. La Venta primates are closest to the extant forms. Two additional genera from the Pleistocene of Brazil have been also recovered, as well as three taxa from the late Miocene of Río Acre, Brazil, and four from the Pleistocene and Holocene of the Greater Antilles. Recent estimations on divergence times of the primate phylogeny suggest an age for the crown group Platyrrhini that allows the inclusion of the Patagonian fossil primate. Another scenario supporting the evolutionary continuity between the Patagonian and Amazonian lineages is a possible paleobiogeographic corridor throughout western South America, considering that by that time the Andean cordillera did not represent a significant geographic barrier to avoid the primate dispersal.