THE BIOGEOGRAPHY OF SOUTH AMERICAN CARNIVORES (MAMMALIA, CARNIVORA) IN THE CONTEXT OF THE GREAT AMERICAN BIOTIC INTERCHANGE

PREVOSTI, F. J.; SOIBELZON, L. H.

Simposio; VII Simposio Brasileiro de Paleontologia Vertebrados; 2010

Placental carnivores (Order Carnivora) have a short history in South America, tightly related to the biogeographic event called the “Great American Biotic Interchange” (GABI). The oldest records of the group in South America come from the Late Miocene (≈ 6-7 Ma) and correspond to extinct procyonids, followed by mustelids and canids in the Late Pliocene (≈ 2.5 Ma). However most families, genera and species have been recorded since the Early Pleistocene (≈ 1.8 Ma). Albeit their short “history” in South America, carnivores have been very successful, diverse and well represented in this continent. In this paper we review the biogeographic patterns of South American carnivores using the fossil record, recent published phylogenies, and the geographic distribution of living and extinct species. The available information suggests that the South American carnivore fauna resulting from several independent immigrations including different lineages, plus an important component of in situ speciation. Immigrations events happened independently several times within each family and, in some cases, within each genus. One interesting pattern observed in recent carnivores, is that species with a geographic range comprising South America plus Central America and/or North America, are “generalists” (having large distribution areas including different habitats), and inhabits some kind of forested biomes. On the other hand, the species that are adapted to open or arid environments, occupy the southern part of the subcontinent and the dry portions of the Andes. The latter appear to a be a derived condition, and could be the result of invasions to these areas by ancestral populations, or the effect of climatic changes that modified the South American environment during the Pleistocene several times.