Nebraska Academy of Sciences


Date of this Version



Published in Transactions of the Nebraska Academy of Sciences, Volume 4 (1977) pp. 77-93.


Copyright 1977 by the Authors; used by permission of the NAS


Wet gravel pits in Red Willow County, Nebraska have yielded numerous fossil bones from sediments ranging in composition from black peat to coarse gravels. Glaciations to the north and northeast and in alpine situations in the Rocky Mountains may have caused a unique fauna to range into the High Plains in what is now southwestern Nebraska. The mammals recovered consist of twenty-four species. Of these twelve are extinct and six others no longer occur in the area. Geographic ranges are extended for Sangamona, Rangifer tarandus, Symbos cavifrons, Ovibos moschatus, and Ovis catclawensis. Techniques of gravel recovery resulted in mixing of the fauna, which ranges throughout the Latest Pleistocene (Rancholabrean) and into the Holocene. A temperate-to-cold climate is indicated for part of the Late Pleistocene (Post-Sangamon) in southwestern Nebraska.