Freshwater reservoir offsets and food crusts: Isotope, AMS, and lipid analyses of experimental cooking residues

Freshwater reservoir offsets (FROs) occur when AMS dates on charred, encrusted food residues on pottery predate a pot’s chronological context because of the presence of ancient carbon from aquatic resources such as fish. Research over the past two decades has demonstrated that FROs vary widely within and between water bodies and between fish in those water bodies. Lipid analyses have identified aquatic biomarkers that can be extracted from cooking residues as potential evidence for FROs. However, lacking has been efforts to determine empirically how much fish with FROs needs to be cooked in a pot with other resources to result in significant FRO on encrusted cooking residue and what percentage of fish C in a residue is needed to result in the recovery of aquatic biomarkers. Here we provide preliminary assessments of both issues. Our results indicate that in historically-contingent, high alkalinity environments\u3c20%C from fish may result in a statistically significant FRO, but that biomarkers for aquatic resources may be present in the absence of a significant FRO

What do “barbarians” eat? Integrating ceramic use-wear and residue analysis in the study of food and society at the margins of Bronze Age China

The Siwa archaeological culture (ca. 3350 and 2650 cal yr BP) has often been associated with the tribes referenced in textual sources as Qiang and Rong: prized captives commonly sacrificed by the Shang and marauding hordes who toppled the Western Zhou dynasty. In early Chinese writings, food plays a key role in accentuating the ‘sino-barbarian’ dichotomy believed to have taken root over 3000 years ago, with the Qiang and Rong described as nomadic pastoralists who consumed more meat than grain and knew little of proper dining etiquette. To date, however, little direct archaeological evidence has allowed us to reconstruct the diet and foodways of the groups who occupied the Loess Plateau during this pivotal period. Here we present the results of the first ceramic use-wear study performed on the Siwa ma’an jars from the site of Zhanqi, combined with the molecular and isotopic characterization of lipid residues from foodcrusts, and evidence from experimental cooking. We report molecular data indicating the preparation of meals composed of millet and ruminant dairy among the Siwa community of Zhanqi. Use-wear analysis shows that Zhanqi community members were sophisticated creators of ceramic equipment, the ma’an cooking pot, which allowed them to prepare a wide number of dishes with limited fuel. These findings support recent isotope studies at Zhanqi as well as nuance the centrality of meat in the Siwa period diet

The role of salmon fishing in the adoption of pottery technology in subarctic Alaska

Ceramic technology makes an abrupt appearance in the New World Arctic at circa 2800 cal BP. While there is general consensus that the ultimate source of these Alaskan pottery traditions lay in continental NE Asia, the motivations for the adoption of pottery in Alaska have remained unclear. Through organic residue analysis we investigated the function of Norton pottery in Southwest Alaska, and the extent to which its function changed in later periods under the increasing northern influence of Thule culture in the region (from ca. 1000 cal BP). Our results show clear evidence of aquatic resource processing in all pottery vessels. Regional variability due to environmental and ecological differences are apparent in the pottery. The majority of Norton pottery was from inland riverine locations and the function of this early pottery was to process anadromous fish, with only limited evidence of other resources. After 1000 cal BP more sites appear on the coast, and while pottery technology changes dramatically at this time, this is not as clear in pottery function which remains aimed at local abundant aquatic resources. We hypothesize that pottery was adopted into Alaska as part of a riverine adaptation and suggest that targeted human exploitation of large riverine systems may have facilitated its expansion into Southwest Alaska. Furthermore, we suggest that this pattern might extend back into Siberia where Alaskan pottery originates

Structure and regional diversity of the Meadowood Interaction Sphere

In northeastern North America, elaboration of mortuary ceremonialism and the widespread distribution of Onondaga chert bifaces during the Early Woodland period (3,000-2,400 BP) have been attributed to the development of the Meadowood Interaction Sphere. The mechanisms underlying the flow of goods and ideas, the structure of the network, and the incentives of the participating groups, however, remain poorly understood. This study aims at discriminating between ritual, economic, and socio-political interpretations of the Meadowood Interaction Sphere through a pan-regional survey of its manifestations. The ritual model defines Meadowood as a “Burial Cult” and ascribes the sharing of traits to the diffusion of religious ideas and cult items. According to the economic model, alliances between groups are based on economic reciprocity and serve to increase the stability of local subsistence systems. The socio-political model involves successful traders increasing their status through their ability to obtain prestige items. To evaluate these scenarios, this research examines Meadowood material manifestations, their contexts of use, the spatial distribution of sites and artefacts, as well as subsistence strategies and social organization. The role of Meadowood trade goods as prestige items is supported by their fine craftsmanship and their occurrence in both residential and mortuary/gathering contexts. Meadowood manifestations concentrate in resource-rich areas, where communities have the greatest potential to produce surpluses and develop socioeconomic inequalities. Moreover, this study demonstrates an increasing dependence on abundant and predictable resources. Also significant is the recognition of distinct regional networks, where Meadowood groups are strategically located to act as “middlemen” between Atlantic and Midwestern communities. Finally, the presence of burial precincts distinct from habitation sites, variability in mortuary treatments and grave good distributions, and evidence of funerary feasts reflect social inequalities, ownership, and competitive displays of success. The data presented in this study converge on socio-political forces being the major underlying factors for the establishment of Early Woodland interregional networks in northeastern North America. The development of socioeconomic inequalities and an attempt by individuals or corporate groups to enhance their status through privileged access to rare goods were central in maintaining the contacts that constitute the essence of the Meadowood Interaction Sphere

Correction: Freshwater reservoir offsets and food crusts: Isotope, AMS, and lipid analyses of experimental cooking residues.

[This corrects the article DOI: 10.1371/journal.pone.0196407.]

Regression of fraction fish C on fraction dead carbon.

<p>Regression of fraction fish C on fraction dead carbon.</p

Freshwater reservoir offsets and food crusts: Isotope, AMS, and lipid analyses of experimental cooking residues - Fig 7

<p>Partial m/z 105 ion chromatograms showing ω-(o-alkylphenyl)alkanoicacids with 16(+), 18(*), and 20(#) carbon atoms in heated samples containing lake trout (A), chain pickerel (B) and maize (C).</p

Freshwater reservoir offsets and food crusts: Isotope, AMS, and lipid analyses of experimental cooking residues - Fig 5

<p>Gas chromatograms of lipid extracts from unheated maize-fish powder mixes consisting of 90% Lake Trout and 10% maize (A) and 10% Lake Trout and 90% maize (B). Cn:x are fatty acids with carbon length n and number of unsaturations x; br are branched-chain acids; IS is internal standard (n-hexatriacontane).</p

Percent raw fish resulting in significant FRO with different radiocarbon date error terms.

<p>Percent raw fish resulting in significant FRO with different radiocarbon date error terms.</p