Assessing parasite epidemiology in the epidemiological importance of Patagonian Late Holocene rockshelters using carnivore coprolites in the past: new data from Piedra Parada, Argentina

The aim of this research was to analyse the variability of parasite assemblages on a small spatial scale, by examining carnivore coprolites from the archaeological site Campo Moncada 2 (CM2), Piedra Parada area, Chubut province, Argentina, and comparing the results with those previously obtained from the archaeological site Campo Cerda 1 (CCe1), located in the same area. Six carnivore coprolites from CM2 were analysed: 4 obtained in sub-level 2a and 2 obtained in sub-level 2a/b. Two radiocarbon dates associated with the coprolites placed the samples chronologically between 780 +/- 80 and 860 +/- 80 years before present. The rehydrated sediments were sieved and then allowed to sediment spontaneously. The sediment was used for parasitological examination under light microscopy. Conservative estimation of total parasite richness resulted in 21 parasitic taxa. The taxa with the highest fecal prevalence (>50%) corresponded to parasites prevalent in modern carnivores (Alaria sp., Toxocara cf. cants, Toxascaris sp., Eucoleus cf. aerophila, Trichuris sp. and Ancylostomatidae gen. sp.). Assuming that the fox coprolites are contemporaneous, the total fecal parasite richness estimated for CM2 and previously for CCe1 was similar. The high total parasite richness found suggests a network of host-parasite relationships that could include regional hunter-gatherers. The results obtained in carnivore coprolites allow us to infer a very diverse biological community in Piedra Parada area, so the regional caves and rockshelters could have a proportional epidemiological importance as parasite exchange nodes.