Patagonian Desert whom 3,000 ended up in Buenos Aires separated by sexes to avoid their procreation. The boundary treaty of 1881 between Chile and Argentina bought most of the desert under definitive Argentine sovereignty; previously Chile had claimed varying now Argentine areas under claims of inherited colonial titles. In the few decades before and after 1900 the less dry parts of the Patagonian steppe experienced a sheep farming boom, transforming the region into one of the world's greatest exporters of ovine products. The area is sparsely populated today and those that do live here survive mainly by the raising of livestock such
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