Quaternary of Tierra del Fuego and southernmost Patagonia

Abstract

In the Fuego-Patagonian region, except for a very few exceptions, no mammals that may be clearly correlated with those characterizing the upper most Miocene-Early Pleistocene units of the extra-Patagonian area (Montehermosan, Chapadmalalan, Marplatan and Ensenadan stages) have been recorded. The remains of the Late Pleistocene in Patagonia are diverse and relatively frequent, but almost restricted to those representing approximately the last 15,000 years, many of which are directly or indirectly associated with archaeological sites. The goals of this contribution are: 1- to present an updated revision of the information about Late Pleistocene and Middle Holocene fauna records in archaeological/palaeontological sites of the Fuego-Patagonian region (43º 30´-55º 30´S), and 2- to comments the climatic conditions that occurred in Patagonia during this period. During the Antarctic Cold Reversal, several species of pampean herbivore megamammals expanded their distribution to reach the south of Patagonia and Tierra del Fuego. These herbivores were accompanied by their potential predators. This expansion of the distribution towards high latitudes can be attributed to environmental conditions that favored the increase of primary productivity. However towards the end of the Pleistocene and beginning of the Holocene, these mammals became extinct. In Patagonia, the extinction of megamammals occurred with a combination of climatic change and human presence. Although it is unlikely that human predation was the sole cause of extinction of all large/megafauna, it may have reduced population sizes of some large/megamammals, particularly in environmental change conditions. Human settlement in South America could have occurred since ca.18,500 and 14,500 years cal BP. Extinctions occurred prior to, during and after human colonization. There is some evidence of extinct fauna surviving into the Early Holocene, implying that some megamammals and large mammals persisted for some millennial alongside people.