The 89th Annual Meeting of the American Association of Physical Anthropologists (2020)

The role of stable hydrogen isotope analysis of bone collagen in refining dietary interpretations at prehistoric Paquimé (Casas Grandes), Mexico


1Anthropology & Archaeology, University of Calgary, 2Applied Geochemistry - Isotope Science Laboratory, University of Calgary

April 16, 2020 , Platinum Ballroom Add to calendar

Previous isotopic analyses at prehistoric Paquimé indicated meat consumption varied between individuals, but the contribution of plant proteins to these values was not clear. Trophic level interpretations can also be complicated in arid environments because of the physiological effects of water-stress on stable nitrogen isotope tissue values. Collagen stable hydrogen isotope values, which reflect drinking water and dietary hydrogen sources, increase with each trophic level and can also be used to compare the relative amounts of dietary plant and animal protein between individuals.

In order to refine our previous interpretations, 71 human individuals from Paquimé were analyzed for their collagen stable hydrogen isotope values. After accounting for the exchangeable hydrogen in the samples, the stable hydrogen isotope ratios range from -18.8 to +30.6 per mil. We also estimated the isotopic values of meteoric precipitation and of herbivore tissues using the stable oxygen isotopes from tooth enamel from the same individuals. Plant-based diets will correlate more closely with these estimates than those that included more animal protein.

The results show that while most individuals at Paquimé incorporated some meat into their diet, plant proteins remained important. Young adults appear to have consumed more animal protein than adolescents and older adults, but other characteristics associated with social differentiation do not correspond to any particular dietary pattern.

This study demonstrates the benefit of incorporating stable hydrogen isotope analysis into research questions about protein sources. By refining isotopic knowledge about past diet, we are better able to understand human omnivorous adaptations to semi-arid environments.

  This research is supported by the Social Sciences and Humanities Research Council of Canada.

Slides/Poster (pdf)