SUMMARY AND CONCLUSIONS

Recently discovered caves in the central Andes of Perú have yielded numerous fossils that provide clues regarding life in that region during the Pleistocene. Many of the specimens are well preserved and are providing a wealth of morphological and even molecular data for works in progress. Our initial results may be summarized as follows:

• Over 100 Pleistocene mammal fossils have been recovered from three caves in the Peruvian Andes and are cataloged into the research collection of MUSM, Lima, Perú. This includes the largest collection of fossil vicuña that we are aware of, a few other ungulates, as well as bats, a chinchillid rodent, three genera of sloths, and numerous specimens of rare carnivorans. This also includes a collection of frozen bone samples that will be available for future molecular studies.

• Radiocarbon ages have been obtained for two of the Pleistocene cave faunas. Conventional radiocarbon ages from bone of a horse (†Onohippidium devillei) and Vicugna from Cueva Roselló yielded conventional radiocarbon ages of 23,340 ± 120 BP and 22,220 ± 130 BP, respectively and a †Diabolotherium specimen of Trigo Jirka had a radiocarbon age of 29,140 ± 260 BP (Table 3). Prior to our work, only three Pleistocene cave faunas from the Andes of Perú had been dated via radiocarbon analyses (Huargo Cave [Cardich 1973]; Tres Ventanas [Engel 1970]; and Pikimachay [McNeish et al. 1970]. Our work is the first to use accelerator mass spectrometry to date Andean Pleistocene faunas of Perú.

• We document the oldest occurrence of vicuña in the Altiplano, extending the record from under 12,000 BP (Marín et al. 2007) to at least 22,000 BP, almost doubling the known age of this taxon in the region.

• The successful acquisition of aDNA of sufficient base pair lengths from fossils over 20,000 years of age and from latitudes less than 20° indicates that high elevation caves can be a source of material for molecular studies from low latitude Pleistocene localities. Cool dry conditions frequently encountered at high elevations can delay the degradation of DNA. Caves also shield fossils from damaging UV radiation.