THE MAMMALIAN FAUNA OF THE NORTHERN CHILEAN PATAGONIA - A BIOGEOGRAPHICAL DILEMMA

The northern Chilean Patagonia, in spite of its small size (8,000 km2, 1 % of Chilean territory), major habitat disturbances during the late Pleistocene, and extreme southern location (50-degrees to 53-degrees latitude south), contains a high mammalian diversity with almost 50 % of Chile's total native terrestrial mammals. The most diverse groups of mammals in the area are the rodents and carnivores, representing 50 % and 23 % of the mammalian fauna, respectively. The major reasons that the region has such an unusually high mammalian diversity seem to be high habitat diversity and the combination of two different faunas, species that originated on the Chilean side of the Andes (Chilean-Andean origin = 72 %) and those from the Patagonia steppe of the Argentinian side of the Andes (28 %).