Stable Isotope Analysis of Diet-based Social Differentiation at Late Prehistoric Collective Burials in South-Western Portugal

Abstract

In the Neolithic and Copper Age collective burials of the Portuguese Estremadura, the majority of material culture and skeletal remains are highly commingled, making it difficult for archaeologists to evaluate social status by linking individuals with specific grave goods. In these circumstances, bio-anthropological data about individual life histories offer an additional avenue of investigation into social complexity among prehistoric communities practising collective burial. In this study, stable isotope data were gathered from 81 individuals from seven collective burial sites and one settlement, the fortified site of Zambujal, in order to determine if significant dietary differences exist within or between burials that may point to patterns of social differentiation, both at individual sites and across the region. While in general all of the sampled individuals consumed fairly homogeneous diets based on terrestrial animal proteins and C 3 plants, this study found that statistically significant differences in δ 13 C ap and δ 15 N values exist between several sites, which may indicate socially differentiated consumption of meat and plants. Additionally, statistically significant differences were found in δ 15 N values between adults and juveniles, which may either be attributable to proteinrestrictive child-feeding practices or physiological processes related to skeletal growth and development.

Stable isotope ratio analysis of bone collagen as indicator of different dietary habits and environmental conditions in northeastern Iberia during the 4th and 3rd millennium cal B.C.

“…This homogeneous pattern of diet based on C 3 terrestrial resources seems to be general along the entire Iberian Peninsula during the Late Neolithic and Chalcolithic (e.g. Alt et al 2016;Díaz-Zorita 2014;Fernández-Crespo et al 2016;Fontanals-Coll et al 2015;García-Borja et al 2013;López-Costas et al 2015;McClure et al 2011;Sarasketa-Gartzia et al 2017;VillalbaMouco et al 2017;Salazar-García 2011;Salazar-García et al 2013b;Salazar-García 2014;Waterman et al 2016). The reason of this homogeneity could be the consolidated economy based on agriculture and livestock, together with a higher mobility among the different communities and the increase of trade networks, not only in prestigious objects (Schuhmacher and Banerjee 2012) but also in food products.…”

First insight into the Neolithic subsistence economy in the north‐east Iberian Peninsula: paleodietary reconstruction through stable isotopes

“…The method followed to extract the collagen was the one established by Richards and Hedges (1999), including Brown et al's (1988) modifications as regards the ultrafiltration phase using >30kDa fraction with precleaned Amicon V C ultrafilters (Millipore). To ensure the correct preservation of the collagen, different quality controls were applied to detect possible diagenetic alterations or contamination (DeNiro, 1985;Ambrose, 1993;Van Klinken, 1999 and Tuross, 2010), or may be related to a compromised health due to their premature death (Waterman et al, 2015).…”

“…Lubell et al, 1994;Umbelino and Cunha, 2012;Carvalho and Petchey, 2013;Fontanals-Coll et al, 2014;Waterman et al, 2015) and the northern coast (e.g. Most of these have focused on Mesolithic to Copper Age sites on the Atlantic seaboard (e.g.…”

Archaeology, chronology, and age‐diet insights of two late fourth millennium cal BC pit graves from central southern Iberia (Córdoba, Spain)

“…In the first place, there are no differences of δ 15 N values between juveniles and adults. The existence of these differences in contemporary prehistoric sites in the south of Spain is usually explained by ethnographic models (Fontanals‐Coll, Díaz‐Zorita, & Subirà, ; Waterman et al, ) that suggest social practices favouring a differential consumption of meat for adults. The only evidence pointing the health conditions in life of the individuals under study is offered by their dentition.…”