Linking isotope analysis and paleopathology: An andean perspective.

This paper reviews the significant advances in isotopic investigations in Andean South America and directs scholars to explore new theoretical and analytical directions, specifically the applicability of isotope data to paleopathology. Excellent preservation and large skeletal collections of human remains make the Central Andes ideal for biogeochemical reconstructions and advancements in isotopic methods. Our aims are twofold: first, we present a meta-analysis of stable and radiogenic isotope research in the Central Andes since 1985, and highlight those that combine analyses of isotope ratios and pathological conditions. Second, we discuss useful directions for incorporating stable isotope analysis more explicitly in studies of paleopathology in the Andes more in the future. Principle research foci have described dietary variation and regional population mobility since the 1980s, where early methodological explorations identified significant trends in isotopic variation. For the years 1980-2017, we identified 96 scholarly publications through a meta-data analysis of major peer-reviewed journals, book chapters, and conference proceedings. These demonstrate specific trends in topical and methodological preferences across the Andean region and a shift from 10 publications pre-1997 to 67 in the last 10 years. However, combined isotope and paleopathology studies in this region remain sparse; given the ecological, geological, and cultural complexity of the Central Andes, analyses of pathological conditions in different regions would significantly benefit from the information on diet, mobility, and local ecology that isotope ratios provide. Isotope analysis requires destruction of archaeological tissues, and interpreting isotope data can be complex, but it can also provide unique insights into the pathogenesis of multifactorial conditions and assist differential diagnosis. Therefore, we also discuss research designs for pairing isotopic and paleopathological variables that will allow researchers to better capture disease ecologies in archaeological samples and their variation across different regions, within related sites, and within individual lifespans.

Analysis of nutritional disease in prehistory: The search for scurvy in antiquity and today.

In this paper, we discuss the issues surrounding the study of scurvy, or vitamin C deficiency, in paleopathology, and highlight the work of Donald Ortner in advancing this area of research. This micronutrient deficiency impacts collagen formation and results in damage to a variety of bodily tissues. While clinical manifestations are observed routinely, the lack of specific signatures on bone makes paleopathological diagnosis difficult. Rapid growth in infants, children, and subadults provides abundant remodeled tissue and an increase in vascularization that makes identification possible in younger segments of the population. However, diagnosis of scurvy in adults remains problematic, given that diagnostic lesions are strikingly similar to those associated with rickets, osteomalacia, and other conditions. We argue that this confounding factor underscores the need for a broader anthropological approach to scurvy research that expands beyond differential diagnosis to include more accurate reconstruction of diets and available resources, greater consideration of the possibility - even likelihood - of multiple nutrient deficiencies simultaneously affecting an individual, and the patterning of these deficiencies along lines of status, sex, and age.

Beyond the Paleolithic prescription: incorporating diversity and flexibility in the study of human diet evolution.

Evolutionary paradigms of human health and nutrition center on the evolutionary discordance or "mismatch" model in which human bodies, reflecting adaptations established in the Paleolithic era, are ill-suited to modern industrialized diets, resulting in rapidly increasing rates of chronic metabolic disease. Though this model remains useful, its utility in explaining the evolution of human dietary tendencies is limited. The assumption that human diets are mismatched to the evolved biology of humans implies that the human diet is instinctual or genetically determined and rooted in the Paleolithic era. This review looks at current research indicating that human eating habits are learned primarily through behavioral, social, and physiological mechanisms that start in utero and extend throughout the life course. Adaptations that appear to be strongly genetic likely reflect Neolithic, rather than Paleolithic, adaptations and are significantly influenced by human niche-constructing behavior. Several examples are used to conclude that incorporating a broader understanding of both the evolved mechanisms by which humans learn and imprint eating habits and the reciprocal effects of those habits on physiology would provide useful tools for structuring more lasting nutrition interventions.

The variable roads to sacrifice: Isotopic investigations of human remains from Chotuna-Huaca de los Sacrificios, Lambayeque, Peru.

This study investigates two key variables-residential context and subsistence-among sacrificial victims dating to the Late Horizon (A.D. 1450-1532) in the Huaca de los Sacrificios at the Chotuna-Chornancap Archaeological Complex in north coastal Peru. We investigate whether aspects of sacrifice in this distant coastal province mirrored that found in Inca heartland contexts such as the capacocha, or remained more typical of coastal sacrificial traditions. Stable carbon, nitrogen, and oxygen isotope values were characterized in bone carbonate, bone collagen, and hair keratin to estimate geographic residence during the decade before death and diet in the decade, versus months, before death. Bone δ18 Ocarbonate values have a mean (±SD) of 26.8 ± 1.1%, bone δ13 Ccarbonate values -6.7 ± 1.7%, and bone δ(13) Ccollagen values 11.8 ± 1.3%; bone δ15 Ncollagen values have a mean of 11.5 ± 1.3%. Combined hair δ13 Ckeratin values have a mean of -12.8 ± 1.6%, and hair δ15 Nkeratin values 10.8 ± 1.3%. In contrast to contemporaneous coastal and highland contexts, we are unable to identify immigrants among the sacrificed individuals or changes in diet that indicate provisioning with a standardized diet leading up to death. Instead, results suggest that victims were local to the area, but consumed moderately variable diets consistent with local subsistence patterns. These findings suggest a distinct pattern of human sacrifice in the Late Horizon and underscore the regional and temporal variation in sacrificial practices in the central Andes.

Diet, residential origin, and pathology at Machu Picchu, Peru.

Pathological conditions in human skeletal remains provide a wealth of information about archaeological populations, but many are limited in their interpretive significance by their nonspecific etiologies. This study analyzes three common pathological conditions known to manifest in infancy and childhood in the skeletal population from Machu Picchu, Peru (N = 74) with published carbon, nitrogen, oxygen, strontium, and lead isotopic data (Turner et al.: J Archaeol Sci 36 (2009) 317-332; Turner et al.: Chungara: Revista de Antropología Chilena 42 (2010) 515-524) to distinguish early-life diet from residential origins as significantly associated with pathologies among the site's inhabitants. Analyses of variance indicate highly significant variation between enamel δ(18)O values, which serve as a rough proxy of local environment, and both cribra orbitalia (CO) and porotic hyperostosis (PH), generally understood to be markers of anemia. Results tentatively suggest that individuals manifesting these lesions may have lived closer to the arid coasts; however, no significant variation was found in parameters of diet (enamel δ(13) C(carbonate), dentin δ(13) C(collagen), dentin δ(15)N) by either CO or PH, suggesting that the primary factors causing anemia may have been more significantly related to residential origin rather than diet. Linear enamel hypoplasia (LEH) frequency significantly varied by both dietary and residential parameters, supporting models of LEH formation from a synergy of dietary and environmental factors. These results support previous research on the etiology of PH in the Andes; they also represent a useful approach to refining site-specific interpretations of pathological conditions in archaeological populations, and exploring etiological variation between populations.