Monte Desert not only common, but tall cacti even appear in the more hospitable areas of the desert. The fauna of the area is also very similar to that of the Patagonian Desert, only in greater diversity and number due to the Monte's more hospitable conditions. Small mammals like mice abound and larger animals like the guanaco and burrowing owl can be found as well. Monte Desert The Monte Desert is a South American ecoregion, lying entirely within Argentina and covering approximately the submontane areas of Catamarca, La Rioja, San Juan, San Luis and Mendoza Provinces, plus the western half of La
Patagonian opossum of La Pampa and Choele Choel (northern Rio Negro Province). It is suggested that the Patagonian opossum may have emerged from the same ancestral group as "Marmosa". They resemble each other closely. In the winter both types have similarly thickening at the base of the tails, where fat accumulates. Yet they do not share all aspects of their lifestyle; Patagonian opossums have a specialized way to gather and consume food, which is made possible by the shortening of their skull and jaws. The shortening occurs in the premolar region; this gives the Patagonian opossum increased biting power. The general appearance