Withering Snow and Ice in the Mid-latitudes: A New Archaeological and Paleobiological Record for the Rocky Mountain Region
Keywords:climate change, ice patches, organic artifacts, dart shaft, foreshaft, bighorn sheep, bison, Rocky Mountains
In the mid-latitude mountains of North America, archaeological materials have been identified in association with kinetically stable “ice patches” that attracted animals and their human predators. The stable ice in these features exhibits little internal deformation or movement and can preserve otherwise perishable materials for millennia. Eight prehistoric sites have been identified in association with perennial ice patches within the Greater Yellowstone Area of Montana and Wyoming. Surveys in Colorado have produced paleobiological samples, but no definitive archaeological sites. Archaeological remains include ancient wooden dart shafts and fragments, wooden artifacts of unknown function, a wrapped leather object of unknown function, butchered animal remains, and chipped stone artifacts. Fragments of weapons ranging in age from 200 to 10 400 years suggest long-term continuity in ice patch hunting in the region. Paleobiological specimens range in age from several hundred to nearly 8000 years. Bighorn sheep (Ovis canadensis) is a presumed prey species, but the remains of bison (Bison bison) and other large ungulates also occur. Ice patches offer important insights into the use of high-elevation environments by Native Americans. Efforts are ongoing to build and maintain awareness of these resources among federal land managers and the public.