Microhistological analysis of ancient camelid dung from the southern Argentinean Puna: Past vegetation composition and diet

Abstract

Identification of plant micro-remains in ancient dung is a tool used infrequently in archaeological studies to infer past vegetation diversity and herbivore diet. Through the microhistological analysis of dung of South American camelids from two micro-sectors of a rockshelter archaeological site in the Puna of Catamarca (Argentina), we identified plant micro-remains to illuminate our knowledge of the environment and the use of camelids during the late Holocene (540 ± 40 years BP). Grasses were the main plant category found in dung samples of both micro-sectors, followed by sedges (Cyperaceae), shrubs and annual herbs. However, relative abundance of several species and vegetation type varied between samples. Differences were also detected in the abundance of species from vegas (high Andean wetlands) and open areas. Our results could be explained by several factors, such as the season of the year in which dung was produced, differences in foraging habitats and foraging behavior of camelid species. Our work underscores the importance of microhistology as a useful tool for future paleoenvironmental studies. This method, combined with other reconstruction techniques (pollen, stable isotopes and macro-vegetation remains), has the potential to provide insights of paleovegetation histories and the use of wildlife by hunter-gatherers of the Southern Puna during the entire Holocene.