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Résumé

Bones of yellow-bellied marmot occur in various archaeological sites associated with caves and rockshelter site in the Great Basin and southwestern United States, but local extinctions and range changes for this marmot have been attributed to climatic changes rather than prehistoric overkill. Bones of yellow-bellied marmot occur in various archaeological sites associated with caves and rockshelter site in the Great Basin and southwestern United States, but local extinctions and range changes for this marmot have been attributed to climatic changes rather than prehistoric overkill.This monograph presents the results ofthe analysis of faunas from three caves and rockshelters in the northern half of the Great Basin: Danger Cave (Tooele County, western Utah), Last Supper Cave (Humboldt County, northwestern Nevada),and Hanging Rock Shelter (Washoe County, northwestern Nevada). The Danger Cave fauna was excavated by Jesse D. Jennings between 1949 and 1953. A total of 3628 Danger Cave bones and teeth were identified to at least the genus level, of which 3513 are mammalian, 114 are avian, and 1 is reptilian. Stratigraphic analysis of this fauna shows that the major change in the nature of the vertebrate fauna in the western basin of Pleistocene Lake Bonneville occurred at ca. 10,000 B.P. At this time, a series of relatively mesic-adapted taxa seems to have become locally extinct: pygmy rabbits (Sylvilagus idahoensis), yellow-bellied marmots (Marmota flaviventris), and Sage Grouse (Centrocercus urophasianus). This faunal shift indicates a decrease in locally available mesic habitats, and correlates well with the suggested retreat of Lake Bonneville from the Gilbert level at about 10,000 B.P. It does not support suggestions that Lake Bonneville did not exceed historic levels between ca. 14,500 and 3500 B.P. In documenting the local presence of yellow-bellied marmots and bushy-tailed wood rats along the lower elevations of the Silver Island Mountains, the Danger Cave fauna adds significant support to J. H. Brown's account of the history of boreal mammals in the Great Basin. The decline in the abundance of pygmy rabbits at ca. 10,000 B.P. here may be correlated with the terminal Pleistocene extirpation of these animals from the Southwest, and suggests that these leporids underwent two periods of prehistoric decline in the Great Basin: one at the end of the Pleistocene (documented only from Danger Cave), and one at about 7000 B.P. (documented from a number of sites in the northern Great Basin). Last Supper Cave was excavated by T. N. Layton between 1968 and 1973, and by J. 0. Davis in 1974. The faunal collection retrieved by these excavations provided a total of 9095 vertebrate specimens that could be identified to at least the genus level. Of these, 8975 are mammalian, 63 are reptilian, 56 are avian, and 1 is amphibian. Although the Last Supper Cave sediments were deposited over at least 11,000 years, most of the faunal materials from the site came from wood rat middens that lined the walls of the cave. Radiocarbon dates spanning the last 2000 years were obtained for midden in the rear of the site. There is little correlation between depth and age of the dated material in that midden, hence the entire faunal assemblage from that setting is treated here as a single analytic unit. In addition to the vertebrate specimens, a total of 1412 valves of Margaritifera falcata were identified from the Last Supper Cave fauna. Initial reports on Last Supper Cave noted that units deposited between about 9000 and 7000 B.P. contained concentrations of these shells. However, all shells available to us came either from the rear wood rat midden or lacked provenience. Last Supper Cave also provided a small number of wapiti (Cervus elaphus) specimens. These animals are unknown historically from northwestern Nevada and adjacent Oregon; the Last Supper Cave specimens join those from Fort Rock Cave, the Connley Caves,