Diet and gender in the Tiwanaku colonies: Stable isotope analysis of human bone collagen and apatite from Moquegua, Peru.

OBJECTIVES: Gender and other facets of social identity play important roles in the organization of complex societies. This study reconstructs dietary practices within the Middle Horizon (AD 500-1000) Tiwanaku colonies in southern Peru to increase our knowledge of gendered patterns of consumption within this early expansive state. METHODS: We use stable isotope analysis of 43 human bone samples representing 14 females, 20 males, 8 juveniles, and 1 indeterminate individual recovered from burial excavations at the sites of Rio Muerto and Omo in the Moquegua Valley. Data are contextualized by comparisons with previously published Tiwanaku isotope data from the period. RESULTS: Our results find mean values of δ(13) Capatite = -7.3 ± 1.6% (N = 36, 1SD), δ(13) Ccollagen = -12.3 ± 1.5% (N = 43, 1SD), and δ(15) Ncollagen = 8.4 ± 1.6% (N = 43, 1SD). Between the sexes, Mann-Whitney U tests demonstrate significant differences in δ(13) Ccollagen (U = 74, P = 0.021), but no differences in δ(13) Capatite (U = 58, P = 0.095) or δ(15) Ncollagen (U = 116, P = 0.755) values. CONCLUSIONS: These data indicate relatively high C4 plant consumption among the Tiwanaku colonies, and support paleobotanical and archaeological evidence that maize (Zea mays) was the staple crop. Dietary values are similar overall between the sexes, but significantly higher δ(13) Ccollagen values in males is consistent with a model of gendered norms of consumption similar to that of the later Inca (AD 1438-1533), where males consumed more maize than females, often in the form of beer (chicha). Results provide new insights on social dynamics within the Tiwanaku colonies and suggest the increased importance maize consumption for males during the Tiwanaku expansion.

Paleomobility in the Tiwanaku diaspora: biogeochemical analyses at Rio Muerto, Moquegua, Peru.

Paleomobility has been a key element in the study of the expansion of ancient states and empires, including the Tiwanaku polity of the South Central Andes (AD 500-1000). We present radiogenic strontium and oxygen isotope data from human burials from three cemeteries in the Tiwanaku-affiliated Middle Horizon archaeological site complex of Rio Muerto in the Moquegua Valley of southern Peru. At Rio Muerto, archaeological human enamel and bone values range from (87) Sr/(86) Sr = 0.70657-0.72018, with a mean of (87) Sr/(86) Sr = 0.70804 ± 0.00207 (1σ, n = 55). For the subset of samples analyzed for oxygen isotope values (n = 48), the data ranges from δ(18) Ocarbonate(VSMOW) = +18.1 to +27.0‰. When contextualized with other lines of archaeological evidence, we interpret these data as evidence for an archaeological population in which the majority of individuals had "local" origins, and were likely second-generation, or more, immigrants from the Tiwanaku heartland in the altiplano. Based on detailed life history data, we argue a smaller number of individuals came at different ages from various regions within the Tiwanaku polity. We consider whether these individuals with isotopic values consistent with "nonlocal" geographic origins could represent first-generation migrants, marriage exchange partners, or occupationally mobile herders, traders or other travelers. By combining isotopic life history studies with mortuary treatment data, we use a person-centered migration history approach to state integration and expansion. Isotopic analyses of paleomobility at the Rio Muerto site complex contribute to the role of diversity in ancient states by demonstrating the range of geographic origins rather than simply colonists from the Lake Titicaca Basin.