Taphonomic Trajectory of Diagenesis: How Site Formation Should Inform Biological Sampling Strategies for Isotopic Studies of Ancestors.

OBJECTIVES

Stable isotope analyses of archaeological bone have become an increasingly common research avenue for interpreting past human behavior. To ensure reliable isotope data is used for interpretations, bone samples must meet quality control standards. The common quality control measures for bone samples rely on post-sampling destructive approaches. As increasing attention is focused on the ethical use of Ancestors in anthropological research, sampling strategies should prioritize minimal impact to individuals that are less likely to yield viable data for research projects supported by descendant communities.

MATERIALS AND METHODS

Here, I use previously published stable isotope and diagenesis measures from the Vineyards at Marsh Creek Site (CA-CCO-548), supported through tribal consultation and approved by the Most Likely Descendent, as a case study to highlight how geoarchaeology can inform the taphonomic trajectories of individual burials or groups of burials within distinct site formation processes.

RESULTS

Isotope quality control measures indicate that burials located in a context of rapid sedimentation had a higher rate of good bone preservation (100% for collagen and 82% for bioapatite) compared to burials from a stratigraphic context of slow sedimentation in older alluvial deposits (73% for collagen and 63% for bioapatite).

DISCUSSION

Bone preservation corresponds to patterns in site stratigraphy, therefore geoarchaeological data can be used to inform the sampling strategies, rather than relying on post-processing destructive methods for diagenesis assessment. Sampling strategies should become increasingly reliant on contextual information based on nuanced analyses (i.e., geoarchaeology) of local burial environments to better understand the taphonomic trajectory of bone.