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We use published zooarchaeological evidence to discuss the various hypotheses concerning the past distribution of huemuls in Patagonia, southern South America. We then use these data to evaluate the interactions between this cervid and hunter-gatherers during the Holocene. The zooarchaeological record shows that huemul mainly inhabited forested and forest-steppe ecotonal environments during the Holocene. Huemul were hunted in exceptional circumstances during the early occupation of Patagonia. Its presence in the zooarchaeological record of South Patagonia increases after 9500 BP and is more frequent after 2200 BP. However, the taxonomic contribution of the species' bone remains to the archaeological record is always low. The few assemblages where there are a high number of huemul bones would have been the result of opportunistic hunting episodes. This in turn suggests that hunting of huemul had little or no influence on the animal's regional distribution over time. However, the progressively greater human presence in some forested areas towards the end of the Holocene could have affected huemul populations at the local scale. The zooarchaeological information presented in this paper illustrates interspecific and long-term relationships and, hence, could serve as essential information in future management strategies for huemul in Argentina and Chile.

ObjectiveTo study the risk of Trypanosoma cruzi domestic transmission using an entomological index and to explore its relationship with household's characteristics and cultural aspects. Methods There were studied 158 households in an endemic area in Argentina. Each household was classified according to an entomological risk indicator (number of risky bites/ human). A questionnaire was administered to evaluate risk factors among householders. ResultsInfested households showed a wide range of risk values (0 to 5 risky bites/human) with skewed distribution, a high frequency of lower values and few very high risk households. Of all collected Triatoma infestans, 44% had had human blood meals whereas 27% had had dogs or chickens blood meals. Having dogs and birds sharing room with humans increased the risk values. Tidy clean households had contributed significantly to lower risk values as a result of low vector density. The infested households showed a 24.3% correlation between time after insecticide application and the number of vectors. But there was no correlation between the time after insecticide application and T. infestans' infectivity. The statistical analysis showed a high correlation between current values of the entomological risk indicator and Trypanosoma cruzi seroprevalence in children. ConclusionsThe risk of T. cruzi domestic transmission assessed using an entomological index show a correlation with children seroprevalence for Chagas' disease and householders' habits. Resumen Objetivo

Coexistence between species with similar ecological niches implies species must segregate along one or more niche axes to survive. Space, time, and trophic resources are regarded as the principal axes upon which species segregate. We examined segregation along these niche axes to determine mechanisms underlying coexistence between the two main predators, puma (Puma concolor) and culpeo foxes (Lycalopex culpaeus) in the Andes of Central Chile. We used occupancy modeling to examine space use and overlap, Kernel Density Estimation to determine temporal activity patterns and overlap, and analysis of prey remains in feces to assess diet breadth and similarity. We found high spatial overlap and positive associations between detection of the carnivores lending little support for spatial segregation. Similarly, we found high nocturnal, temporal overlap between pumas and foxes that matched peaks in activity of prey. In contrast, we found relatively low dietary overlap indicating niche segregation likely occurs along the dietary axis. The Puma diet was dominated by introduced, exotic hares and foxes appeared to shift away from hares to rabbits, small mammals, and seeds. Given that lagomorphs are the main dietary resource for pumas in particular, management decisions regarding the control or eradication of such exotic species could negatively affected puma survival.

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