Roedores del extremo austral: tafonomía, diversidad y evolución ambiental durante el Holoceno tardío

ULYSES F.J. PARDIÑAS; TETA PABLO; FORMOSO ANAHÍ E.; BARBERENA RAMIRO

Bosques, montañas y cazadores. Investigaciones arqueológicas en Patagonia meridional

Dunken

Año: 2011; p. 1 - 240

We studied archaeological and paleontological small mammal samples from three sites at the southern tip of the Argentinean Patagonia (Orejas de Burro 1, Cóndor 1, and Puesto Pali Aike). These samples are all Late Holocene in age according to radiocarbon dates and are basically composed by osteological remains of rodents. Taphonomical signatures suggest a mixed origin for these assemblages being the trophic activity of strigiform birds (owls) and humans the main accumulator agents. Recent rodent communities in southernmost mainland Patagonia are composed by eight rodent species, while in the fossils ones there are at least eleven. In overall terms, fossil rodent samples suggest environmental conditions similar to the present ones, with predominance of gramineous steppes and open, bare, rocky areas. These conditions were briefly interrupted by a cold-humid pulse around 1,200 years before present that allowed the eastern expansión of several rodents typically associated to western environments. Austral rodent communities seem to be basically stable during the last 3,500 years; by the contrary, the latest Holocene was a time of strong community reworking in northern and central Patagonia. The causes of these differences need further exploration.