GYPSUM CAVE REVISITED: A FAUNAL AND TAPHONOMIC ANALYSIS OF A RANCHOLABREAN-TO-HOLOCENE FAUNA IN SOUTHERN NEVADA

Gypsum Cave, near Las Vegas, Nevada, was excavated in 1930, yielding a Rancholabrean-to-Holocene mammalian fauna intermixed with many human artifacts. The bone assemblage, which is now housed at the Los Angeles County Museum of Natural History, contains burned and fractured bones with conspicuous grooves that had never before been studied. The objectives of this study are to identify and describe the Gypsum Cave fauna, and to interpret the taphonomy of the fauna to test the hypothesis that Gypsum Cave represents a site of interaction between Pleistocene animals and Paleo-Indians. The methods include: identifying the species present; determining their abundance in the cave; determining the age of the fauna; the spatial distribution of the bones; analyzing the fractures and surficial features of the bones; and examining the micromorphology of the burned bone surfaces with an SEM.

The results of this research indicate, (1) The NISP (number of identified specimens) for the Shasta ground sloth and bighorn sheep is high, indicating that these mammals died in the cave, while the NISP for all of the other large herbivores is low, indicating an active bone accumulation, similar to a predator's den, (2) the radiocarbon analyses of fossil material and artifacts do not support Pleistocene co-inhabitance in Gypsum Cave, (3) surface marks on the bones represent non-human gnaw marks and trample marks, as opposed to human-induced tool marks, (4) carnivore damage resembles canid damage, including furrows, splinters, grooves, and gnawed off epiphyseal ends, and (5) the burned bones are the result of a series of sloth dung fires as opposed to human cookery. The surficial bone characteristics are similar to wolf damage, possibly damage created by a dire wolf. These analyses indicate that Gypsum Cave does not represent a site of Late Pleistocene human butchery, but rather a Late Pleistocene predator's lair that was later inhabited and overprinted by humans in the Holocene.