LA DISTRIBUCION DEL GUANACO (MAMMALIA, CAMELIDAE) EN LA PROVINCIA DE BUENOS AIRES DURANTE EL PLEISTOCENO TARDIO y HOLOCENO. LOS FACTORES CLIMATICOS COMO CAUSAS DE SU RETRACCION

Abstract

Some hypothesis explaining the presence and posterior retraction of the guanaco in the Bonarian terrítory are proposed. The dernostration of these hypothesis is based on paleontological, archeological and historícal evidences. 1. The guanaco inhabited all the terrítory of Buenos Aires province during the Late Pleistocene and part of the Holocene. 2. The guanaco inhabited from the Sierras Australes southward and the Bonarian western sandy area when the Spaniards arrived to th e Río de la Plata (XVI th. century ). 3. The guanaco retraction is a consequence of ecological causes related to clirnatic changes, 4. The guanaco inhabited the Interserrana Area and the Pampa Ondulada in some moments during the Late Pleistocene and the Holocene, when the environmental conditions were more arid than today.