A zooarchaeological analysis of bear (Ursus spp.) remains from two archaeological sites in Unalaska, Alaska (4700 BP - 2500 BP)

This dataset contains information about bear specimens (Ursus spp.) identified from two archaeological sites in Unalaska, Alaska: Margaret Bay (UNL-048, 4700 Before Present (BP)) and Amaknak Bridge (UNL-050, 2500 BP). The material is accessioned at the Museum of the Aleutians in Unalaska. Zooarchaeological data included are three dimensional scans (OBJ, MTL, and JPG files for rendering in MeshLab software) and digital photographs. 3D scans were obtained by using a DAVID SLS-3 HD Structured White Light 3D Scanner at the University of Oklahoma Laboratories of Molecular Anthropology and Microbiome Research (LMAMR). Photographs were taken with a Nikon D3400 24.2-megapixel DX format DSLR camera. Zooarchaeological analyses were performed to investigate how bears came to be in Unalaska Bay, a region where bears do not currently live. It has been suggested that this assemblage is evidence of Neoglacial expansion of sea ice in the region and subsequent range expansion of polar bears. Our goals here were to assess whether the bears can be distinguished to species and determine whether these animals were harvested locally and represent a range expansion. The results suggest that bears are very difficult to distinguish using morphological characteristics alone: we argue there is likely a mix of brown and polar bear in this small assemblage, but that morphological analyses alone are inadequate for reconstructing bear distribution in this context. However, the age profiles and butchery patterns do suggest that bears were harvested locally, and we contend that expanding Neoglacial sea ice facilitated their presence around Unalaska Island.