The Casa del Diablo cave (Puno, Peru) and the late Pleistocene demise of megafauna in the Andean Altiplano

During the Late Quaternary Extinction event South America lost ∼83% of all its late Pleistocene megafaunal genera. As in other regions of the world, the debate about the possible drivers behind these extinctions revolves around the role of humans arriving into the continent and on the effect of the climatic changes characteristic of the Pleistocene-Holocene transition. The availability of precise chronological information, in order to estimate the timing of extinction of the different taxa affected, is critical for solving such debate. Here we present an updated study of the late Pleistocene mammalian deposits from Casa del Diablo Cave (CdD) in the Altiplano of Peru. The study includes an updated list of the mammalian faunas found in the cave and 11 taxon-specific XAD radiocarbon dates from extinct and extant megafauna bones. We compare this new chronology to the timing of major environmental changes and human arrival in the area, as well as with other megafaunal discoveries from the high Andes. The radiocarbon dates from CdD fall in the time window between 23 and 12.8 cal kyr BP. Compared to other records of extinct megafauna in the high Andes, the one from CdD presents in general younger occurrences. No temporal overlap between humans and extinct megafauna emerges from comparing first dates of appearance of humans in the Altiplano, and last appearance dates of extinct megafauna from CdD. However, the possibility of temporal overlap among the records becomes evident when we compare confidence intervals calculated to estimate true times of human arrival and megafaunal local extinctions.