Histological Contributions to Species Identification of Calcined Bone from the Bull Brook and Morrill Point Mound Archaeological Sites
As of 2002, Degree of Master of Science (MS) Quaternary and Climate Studies published under the auspices of the Climate Change Institute.
The highly fragmented nature of burned, cremated, or calcined archaeological bone makes species differentiation difficult. Although gross morphological analyses of calcined archaeological assemblages have provided important contributions to site interpretation, most fragments lack macro-level diagnostic features. However, some questions may only be informed through analysis of such fragments. Studies have demonstrated that histology (microstructure) is preserved in calcined archaeological bone and can provide valuable information in these cases. I contribute to this growing field by identifying histological differences among three important large mammal species - black bear (Ursus americanus), white-tailed deer (Odocoileus virginianus), and caribou (Rangifer tarandus) - and applying these differences in the analysis of calcined bone from the Bull Brook and Morrill Point Mound sites in Massachusetts (10,400 to 3,900 radiocarbon years B.P). Modern samples were taken from the upper limb bones of all species and from cervid metatarsals. Archaeological samples included two bone tools from Morrill Point Mound and seven bone fragments from Bull Brook. Polished transverse sections of these samples were imaged with a scanning electron microscope (SEM) using back-scattered electron (BSE) imaging. In my analysis of the modern comparative samples I found both qualitative and quantitative differences between ursid and cervid specimens and between the closely-related cervid species. I also identified differential characteristics between upper limb bones and metatarsals in cervids. Histological analysis of the Bull Brook archaeological samples provided evidence consistent with identified characteristics of bear and caribou, increasing confidence in tentative identifications based in contextual evidence. Of the two Morrill Point Mound bone tools, my analysis lead to a confident identification of a projectile point as bear right femur. The second tool was more ambiguous, but the observations it provided widens the range of possible species for future research. Living bone is a constantly changing material, formed and maintained through destructive and additive processes. My detailed treatment of each sample emphasizes the need for an understanding of how biological processes during life affect microstructural features observed after death and the recognition that groups of characteristics rather than single universal identifiers are required for species identification.