Predator-prey relationships inferred by coprolite phytolith analysis from Argentine Patagonia

BENVENUTO, MARÍA LAURA; NADIA VELÁZQUEZ; ANA CECILIA MARTÍNEZ TOSTO; NATALIA L. FERNÁNDEZ; CIVALERO, MARÍA TERESA; MARGARITA OSTERRIETH; BURRY, LIDIA SUSANA

Kiel

Congreso; 27th Annual Meeting of the European Association of Archaeologists; 2021

Knowing about past biological interactions is possible thanks to the study of coprolites found in archaeological sites. Evidence of herbivores consumption by omnivorous organisms was found in Patagonia through bone remains studies. With the aim to recognize the limitations and potentialities of the phytolith analysis to infer predator-preyrelationships, a comparative analysis among the content of phytoliths obtained from omnivores and herbivores coprolites was performed. The coprolites were found in thearchaeological site Cerro Casa de Piedra 5, Perito Moreno National Park, Patagonia, Argentina, in an archaeological layer dated to 7,402 cal BP. According to theirmorphological features and content, the coprolites were assigned to omnivoresorganisms and camelids. Samples were rehydrated, filtered, concentrated, dried, andmounted in immersion oil. Counting and identification of phytoliths were made underoptical microscope. The results showed the dominance of phytolith association of thesubfamily Pooideae in the omnivore and camelid coprolites suggesting that the grasseswere part of the diet of these organisms. This result was even confirmed through pollen and plant remains analyze. Also, isolated and articulated phytoliths and preserved silicified cells within the producing plant tissue were observed in camelid coprolites,while in omnivore samples only isolated phytoliths were observed. The presence ofisolated phytoliths in these last samples could indicate that the phytoliths consumed could have been subjected to alteration processes, such as chewing, food processing prior to consumption, digestion or were indirectly incorporated by the consumption ofguanaco viscera, exposing phytoliths on more than one occasion to the alteration processes. Future studies on the qualitative and quantitative production of phytoliths inspecies linked to the diet of herbivores and omnivores as well as on the effects of taphonomic processes from the digestive systems of consumers may contribute to the knowledge of past biological interactions