Mammals of the Ardis Local Fauna 29 



the two species occur sympatrically in areas where the mean July 

 temperature is near 26.7 C (Martin 1968). Today, S. hispidus is com- 

 mon throughout South Carolina, but M. pennsylvanicus is present 

 only in the extreme western Piedmont and in a small relict population 

 near Charleston, South Carolina (Webster et al. 1985). Data from 

 Charleston, South Carolina, over the past 75 years yielded a July 

 daytime mean of 31.1 C and a minimum daily mean of 23.9 C (Pearce 

 and Smith 1984). Vegetational data for the late Wisconsin full glacia- 

 tion, taken from White Pond in South Carolina (Watts 1980), sug- 

 gested a 7 C to 20 C decrease in July temperatures compared to 

 present, and possibly a marginal reduction in precipitation. The pres- 

 ence of M. pennsylvanicus in the Ardis fauna and the absence of S. 

 hispidus may indicate slightly drier conditions and temperatures be- 

 low the mean summer temperature experienced today. 



It has been postulated that mammals in the late Pleistocene reacted 

 to environmental changes based on their own tolerance limits and not 

 as a "community unit" (Graham 1976, 1979). This accounts for northern 

 species pushed south by glaciation and then integrating with the existing 

 biota. Furthermore, southern species also were integrated into the 

 resident community as cooler summers and warmer winters prevailed, 

 producing the "disharmonious fauna" collected from the Ardis fauna. 



In general, the mammalian composition of the Ardis fauna, containing 

 distinctly southern, northern, and western extralimital forms, reflects 

 a climate more equitable than present. The less severe climatic gradients 

 would facilitate the sympatric occurrence of species now ecologically 

 incompatible. The Ardis local fauna coincides well with other late 

 Pleistocene fossil localities reporting disharmonious faunas with similar 

 temporal and topographical settings. This suggests that the late Pleistocene 

 in the southeastern United States was climatically more equitable and 

 ecologically more diverse prior to the dramatic shift towards a modern 

 assemblage, approximately 10,000 to 11,000 y.b.p. (Lundelius et al. 

 1983). 



ACKNOWLEDGMENTS— First and foremost we wish to thank 

 personnel of the Giant Cement Plant for their generous cooperation 

 and patience. They provided, at our request, heavy equipment, opera- 

 tor time, and rerouting of mining operations, to give us maximum 

 possible time for excavations, and nearly unlimited access to the site. 

 A special acknowledgment goes to the plant's safety director, Bert 

 Ardis, for whom the fauna is named. Mr. Ardis went out of his way to 

 ensure our access to the quarry, to provide us food and refreshments, 

 a place to sleep and shower, and field assistance far beyond our 

 hopes. 



