Since the 1970s, the fields of archaeology and geochemistry have used stable isotope analysis for reconstructions of paleodiets and other prehistoric behaviors which have since been used as evidence for topics such as human evolution, migration research, transitions to agriculture, among other topics. Focusing on tooth enamel has allowed researchers to avoid any diagenetic alteration damage since the tissue has high resistance to such a process. However, due to cost and effort, the vast majority of studies analyzing these elements utilize cross-sectional (bulk) sampling, rather than incremental (serial) sampling. Previous studies have shown that there are systematic offsets in values between the two methods, and quantifying these differences across different taxa within an ecosystem adds valuable information for future stable isotope research. In this study, we determine the extent to which information is lost about an organism's diet, water intake, and movement when bulk, rather than serially, sampling along the growth axis of mammalian molars. We do this through the evaluation of samples taken from bovid and equid fossils dating to the Late Pleistocene of southern and western Kenya as a part of a larger project tracking seasonality and migration in eastern Africa from 100-12 ka. Our results for carbon, oxygen, and strontium isotopic analyses indicate that caution is needed when evaluating bulk sampled isotopic samples, as the majority of information stored in each tooth either remains unsampled or is averaged into a single neutral value, erasing information about seasonality and intra-year movements. This has strong implications for both how new research should best be conducted and how paleoecologists should interpret previous studies utilizing bulk sampling.
University / Institution: University of Utah
Format: In Person
SESSION D (3:30-5:00PM)
Area of Research: Science & Technology
Faculty Mentor: Kaedan O'Brien