Taphonomy and paleoecology of the late pleistocene mammalian fauna from Sandia Cave, New Mexico: Poster Session B

Sandia Cave is an important latest Pleistocene(late Rancholabrean) vertebrate fauna, with more than 30 species of mammals, including 9 members of extinct Pleistocene megafauna: Nothrotheriops shastensis, 2 species of Equus, Camelops hesternus, Hemiauchenia macrocephala, Capromeryx minor, Bison antiquus, Mammut americanum, and Mammuthus columbi.When Frank Hibben excavated Sandia Cave inthe late 1930s,he used the presence of these extinct species to argue that associated archaeological materials were also Pleistocene in age. Ataphonomic study of the large mammals has not shown any instances of human modification on extinct or extralimital species, lending no support to Hibben’s argument. Instead, extensive of these fauna. However, a small proportion of unidentifiable bone fragments do display human damage in the form of cut and percussion marks, and bone tools. The ages of these activities will be determined by pending radiocarbon dates. Taphonomic analysis of the lagomorphs and larger sciurids shows no positively identifiable cultural modification, indicating that these smaller mammalian species were accumulated by carnivores or raptorial birds, and then further modified by rodent gnawing. The faunal assemblage from Sandia Cave (elevation 2165 m) also has important paleoecological and paleoclimatological implications. Several cold-adapted small mammals extralimital to the modern Sandia Mountains (maximum elevation~3250 m) have been identified, including the yellow-bellied marmot, Marmota flaviventris. Radiocarbon dates of 16,290 and 24,050 yrBP on M. flaviventris bones from a neighboring cave and 11,850-13,700 yrBP on large mammal bones from Sandia Cave indicate that faunal assemblages from the Sandia Mountains sample the interval from the last glacial maximum through the latest Pleistocene. Holocene bone fragments have likely also been introduced more recently by a combination of human, carnivore, and raptor activity