Ranking de recursos y dieta óptima en desiertos nordpatagónicos.

Prey ranking of animal resources is critical to the evaluation of decision-making of past foragers. Previous work in Central Western Argentina (CWA) has used a ranking of resources on the basis of size and weight alone. Here we present the first CWA resource ranking that incorporates handling costs. Our ranking puts the guanaco (Lama guanicoe) in first place, followed by Rheidae eggs and armadillos (Dasypodidae), and highlights the importance of certain resources commonly assumed to be low-ranking. Following the optimal foraging theory, we develop the diet-breath model (DBM) for two of the most representative environments of North Patagonia: the Monte and Patagonian deserts. The higher encounter rates with the first-ranked prey, guanaco, in the Patagonia desert, discourages the incorporation of lower-ranking resources into the diet. In contrast, lower guanaco encounter rates in the Monte desert favors a wider optimal diet model, including the incorporation of fish (i.e., Percichthys trucha). The DBM was used to (re)interpret temporal trends in human subsistence and to support the idea of an expansion of the diet during the Late Holocene in CWA. In general terms, the DBM expectations are confirmed with the regional zooarchaeological record. [ABSTRACT FROM AUTHOR]