Supplementary material from "Patagonian Partnerships: the extinct Dusicyon avus and its Interaction with Prehistoric Human Communities"

The southern Mendoza province, located in the northern region of Patagonia, was inhabited by hunter-gatherer groups until historic times. Previous archaeological studies have reported canid remains among faunal assemblages, which were assumed to be part of the human diet. However, the taxonomic identification and significance of these canids within human groups have raised questions. In this study, we employed ancient DNA analysis, morphological examination, and stable isotope analysis (δ13Ccol, δ15N) to reevaluate the taxonomic assignment of a canid discovered at the Late Holocene burial site of Cañada Seca. Previous morphological identifications suggested it belonged to the genus Lycalopex, but our results conclusively demonstrate that the individual belongs to the extinct fox species Dusicyon avus. This finding expands Dusicyon avus’ known geographical distribution to Patagonia's northern extremity. Furthermore, statistical predictions based on genetic divergence undermine the hypothesis that hybridization between Canis and Dusicyon, facilitated by the introduction of domestic dogs, played a role in the extinction of Dusicyon species. On the other hand, our findings indicate that a Dusicyon avus individual shared a similar diet and was likely buried alongside humans, suggesting a close relationship between the two species during their lives and deaths.