Paleoparasitological and ancient DNA insights into rodent middens around anthropogenic environments: The study of Topaín and Turi areas (central Atacama Desert, Chile)

The study of paleomiddens in desert environments is crucial for understanding past ecological and environmental dynamics, as these sites offer unique opportunities to preserve ancient biological materials. Rodent middens have contributed significantly to the understanding of biotic responses to late Quaternary environmental changes in arid ecosystems like the Atacama Desert. This region has been home to human populations since ancient times. Paleoparasitology plays an essential role in reconstructing ancient parasite relationships. This study examines the gastrointestinal parasite diversity in rodent middens from the central Atacama Desert, spanning from 2400 cal years BP to modern times, with a focus on exploring the connections between parasites, human activity, and environmental changes. Thirteen parasite species or morphotypes from Nematoda and Coccidia were identified, including two with zoonotic potential, indicating possible exposure risks to ancient populations. Using a combination of ancient DNA (aDNA) analysis, fecal morphology, and specific parasites, two rodent species (Cricetidae and Octodontidae) were identified. Parasite richness and the number of eggs and oocysts fluctuated over time, likely in response to environmental shifts and associated ecological dynamics. This research integrates traditional techniques with aDNA analysis, providing new insights into the health challenges faced by ancient populations and highlighting the need for continued research in this field. It also offers valuable data on how both ancient and modern organisms coped with health threats in a harsh and fluctuating environment. The findings underscore the potential of paleoparasitology to reveal the complexities of ancient parasite dynamics and environmental conditions, paving the way for future interdisciplinary studies.