The xenarthrans are the only group of mammals that originated in South America; there are 31 living species: six sloths, four anteaters, and 21 armadillos. In Argentina, 18 species of xenarthrans were cited. The objectives of this study were to compile the existing information on the distribution of the xenarthrans of Argentina, to use species distribution models to map the potential distribution of these species, and to assess patterns of species richness of this important group of mammals. We obtained a total of 975 records corresponding to 706 different collecting localities from Argentina. We generated species distribution models for 15 of the 18 species present in the country. Virtually all of Argentina is occupied by xenarthrans. The highest richness of species is in the north and northeast of the country in the humid and arid Chaco, probably in relation with the mosaic of ecosystems recorded in these regions. These ecoregions have different degrees of habitat degradation and continues to be a major threat for the viability of the xenarthrans occurring there. The information given in this contribution is an input to clarify occurrence and distribution of this group of mammals.

In this study, we combine species distribution models with a reserve selection approach to assess the degree of representation of xenarthrans in the existing protected area network of Argentina, and to identify conservation priority areas that may help expand the current system. Species distribution models were developed from species' occurrence records using a maximum entropy algorithm. Maps of species distributions were produced for 15 of the 16 species currently present in the country. To assess the performance of the existing protected area network in representing all modeled species, and to identify priority areas to expand the current reserve system, we used the software Zonation. Overall, all species modeled are represented in the existing protected area network. However, the percentage of their ranges covered by protected areas is very low (average = 6.7%; range = 1.7-17.6%). To represent at least 5% of the distribution of each species, 8.8% of the country's area would be needed, and species with restricted ranges have the greatest increase in representation in this scenario. When 10% of the country is set aside for conservation, species representation increases considerably, again favoring range-restricted species. Most of the areas identified as conservation priorities are under strong anthropogenic pressures, including deforestation, agricultural expansion, and hunting. Our analysis provides a preliminary assessment of conservation priorities for the xenarthrans of

<p>El presente trabajo aporta al conocimiento de la biogeografía humana en ambientes áridos y las fases de poblamiento en relación con las trayectorias demográficas humanas. En ese marco, se presenta nueva información arqueológica del área El Corcovo, emplazada en el Monte surmendocino/nordpatagónico. Se detallan los trabajos de campo que contemplaron transectas, excavación arqueológica de un sitio y el relevamiento de arte rupestre de otros tres. Los resultados señalan el inicio de las ocupaciones en torno a 1900 años 14C AP y un cambio en el patrón de movilidad en torno a 600 años 14C AP. Ambas situaciones son consistentes con las estimaciones cronológicas relativas existentes para el arte rupestre del área. Con base en un modelo demográfico regional del Monte, los resultados encuentran dos pulsos de incremento en la señal humana que se corresponden cronológicamente con la fecha inicial de ocupación estimada para el área y con la fecha obtenida para el cambio propuesto. Al asociarse estos pulsos con disminuciones significativas en el sector fitogeográfico de Patagonia se postulan explicaciones alternativas sobre la dinámica poblacional. </p>

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In this paper we evaluate the role of human strategies in the Andean Piedmont from northern Patagonia across the Holocene. Specifically, we present the analysis of the Early Holocene-Late Holocene archaeological record of Salamanca cave (Mendoza-Argentina). We identified technological changes that occurred during the Late Holocene and the implications of a human occupation hiatus in the Middle Holocene. We follow a multiproxy approach by the analysis of radiocarbon dates, archaeofaunal remains, ceramic, lithics and XRF obsidian sourcing. We also discuss a detailed stratigraphic sequence by geomorphological descriptions, the construction of a radiocarbon sequence model and summed probability distributions, compared with other archaeological sites in the region. We conclude that after the Middle Holocene archaeological hiatus, human populations grew while guanaco populations dropped. The imbalance between demography and resources boosted the incorporation of new technologies such as ceramics and the bow and arrow, allowing people to exploit lower-ranked resources.