Unraveling Island Economies through Organic Residue Analysis: The Case of Mocha Island (Southern Chile)

Biophysical conditions played a fundamental role in early human colonization of insular territories, particularly in food-producing societies dealing with limited resources and the challenges of maintaining a sustainable carrying capacity. Studies on past human colonization of small oceanic islands thus offer insights into economic plasticity, ecological impacts, and adaptation of early food-producing groups. On the coast of southern Chile, early evidence is dated to 950 cal BP of island colonization by coastal populations with mainland subsistence systems based on the exploitation of marine resources, along with gathering, managing, and cultivating plants and hunting terrestrial animals. Strikingly, the extent to which these mixed economies contributed to insular colonization efforts is largely unknown. Here we used organic residue analysis of ceramic artifacts to shed light on the subsistence of populations on Mocha Island in southern Chile. We extracted and analyzed lipids from 51 pottery sherds associated with the El Vergel cultural complex that flourished in southern Chile between 950 and 400 cal BP. Chemical and stable isotope analysis of the extracts identified a range of food products, including C3 and C4 plants and marine organisms. The results reveal the central role of mixed subsistence systems in fueling the colonization of Mocha Island

Utilising phytanic acid diastereomers for the characterisation of archaeological lipid residues in pottery samples

Phytanic acid diastereomers, 3S,7R,11R,15-phytanic acid (SRR) and 3R,7R,11R,15-phytanic acid (RRR), were determined by GC-MS in extracts of archaeological ceramic. The SRR% was higher in pottery from coastal sites corresponding with 13C enriched n-alkanoic acid corroborating a predominantly marine origin for the food residues. Conversely, low SRR% and 13C depleted n-alkanoic acid were found at inland sites, which are most likely derived from ruminant products. These observations are explained by differences in the bacterial transformation of phytol to phytanic acid between ruminant and aquatic organisms and allow these products to be easily distinguished in archaeological contexts

Chemical analysis of pottery demonstrates prehistoric origin for high-altitude alpine dairying

The European high Alps are internationally renowned for their dairy produce, which are of huge cultural and economic significance to the region. Although the recent history of alpine dairying has been well studied, virtually nothing is known regarding the origins of this practice. This is due to poor preservation of high altitude archaeological sites and the ephemeral nature of transhumance economic practices. Archaeologists have suggested that stone structures that appear around 3,000 years ago are associated with more intense seasonal occupation of the high Alps and perhaps the establishment of new economic strategies. Here, we report on organic residue analysis of small fragments of pottery sherds that are occasionally preserved both at these sites and earlier prehistoric rock-shelters. Based mainly on isotopic criteria, dairy lipids could only be identified on ceramics from the stone structures, which date to the Iron Age (ca. 3,000 - 2,500 BP), providing the earliest evidence of this practice in the high Alps. Dairy production in such a marginal environment implies a high degree of risk even by today’s standards. We postulate that this practice was driven by population increase and climate deterioration that put pressure on lowland agropastoral systems and the establishment of more extensive trade networks, leading to greater demand for highly nutritious and transportable dairy products

Marine and freshwater shell exploitation in the Early Upper Palaeolithic. Re-examination of the assemblages from Fumane Cave (NE Italy).

The making and use of personal ornaments has been at the centre of a vibrant debate on the origin of modern cognitive behaviour associated with Anatomically Modern Humans within and outside Africa. The Aurignacian deposits of Fumane Cave (NE Italy) offer unique archaeological records in which it is possible to observe evidence of the main cultural symbolic features of European Anatomically Modern Humans. The aim of this contribution is to enhance our knowledge about the ethno-cultural diversity of this period by re-examining shell assemblages associated with personal ornaments. Taxonomical, palaeoecological and taphonomical analyses were performed on a rich assemblage of marine shells retrieved from the Protoaurignacian and Early Aurignacian contexts of Fumane Cave. Over 800 shells (both perforated and unperforated) were recovered, representing 68 different taxa, including 56 gastropods, 11 bivalves and 1 scaphopod. Direct AMS dating of some perforated shells (Homalopoma sanguineum, Nassarius circumcinctus, and Glycymeris nummaria) show strong consistency with other 14C dates obtained from the same sedimentary units, demonstrating that shells were collected on beaches dated to the Marine Isotope Stage 3 (MIS3). A range of use-wear traces and ochre residues observed at stereomicroscope and scanning electron microscope levels on well-preserved perforation edges indicates that the shells were systematically manufactured and used as personal ornaments. Although no clear differences have been observed between the two assemblages, comparisons within the techno-complex confirm that the Aurignacian of Fumane Cave was under the influence of the Southern European ethno-linguistic group

Prehistoric human occupation and littoral exploitation in Caribbean Nicaragua. The data from Karoline shell middens

Ponencia presentada en el 150th Anniversary of the discovery of the Mesolithic Shell-Middens celebrado en Portugal del 21 al 23 de marzo de 2011Peer Reviewe

Deciphering late Quaternary land snail shell δ18O and δ13C from Franchthi Cave (Argolid, Greece)

International audienceThis paper investigates the stable isotopic composition from late Pleistocene–Holocene (~ 13 to ~ 10.5 cal ka BP) shells of the land snail Helix figulina, from Franchthi Cave (Greece). It explores the palaeoclimatic and palaeoenvironmental implications of the isotope palaeoecology of archaeological shells at the time of human occupation of the cave. Modern shells from around the cave were also analysed and their isotopic signatures compared with those of the archaeological shells. The carbon isotope composition of modern shells depicts the consumption of C3 vegetation. Shell oxygen isotopic values are consistent with other Mediterranean snail shells from coastal areas. Combining empirical linear regression and an evaporative model, the δ18Os suggest that modern snails in the study area are active during periods of higher relative humidity and lower rainfall δ18O, probably at night. Late glacial and early Holocene δ18Os show lower values compared to modern ones. Early Holocene δ18Os values likely track enhanced moisture and isotopic changes in the precipitation source. By contrast, lower late glacial δ18O could reflect lower temperatures and δ18Op, compared to the present day. Shell carbon isotope values indicate the presence of C3 vegetation as main source of carbon to late glacial and early Holocene snails

Alkylresorcinol detection and identification in archaeological pottery using ultra-high-performance liquid chromatography-quadrupole/Orbitrap mass spectrometry

Rationale Alkylresorcinols (AR) are cereal-specific biomarkers and have recently been found in archaeological pots. However, their low concentrations and high susceptibility to degradation make them difficult to detect using conventional gas chromatography mass spectrometry (GC/MS). Here we describe the development of a more sensitive liquid chromatography mass spectrometry (LC/MS) method to detect these compounds. Method A method based on the use of ultra-high-performance liquid chromatography (UHPLC) coupled to an Orbitrap mass analyser was established and validated for the detection of low-concentration ARs in pottery. During the preliminary experiments, UHPLC-Q/Orbitrap MS (ultra-high-performance liquid chromatography-quadrupole/Orbitrap mass spectrometry) was demonstrated to be more sensitive, and a wide range of AR homologues in cereal extracts were detected, unlike UHPLC-QTOFMS (ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry) and GC/MS. The developed method was utilised to profile AR homologue distribution in modern cereal samples and reanalyse AR-containing pots from the archaeological site of Must Farm. Results A highly sensitive LC/MS method with a limit of detection (LOD) of 0.02??g/g and a limit of quantification (LOQ) of 0.06??g/g was used to profile ARs in five modern cereal grains. The obtained LOD is 250 times lower than that obtained using the conventional GC/MS approach. AR 21:0 was the most abundant homologue in all four Triticum spp.?einkorn, emmer, Khorasan wheat and common wheat. Meanwhile, AR 25:0 was the predominant homologue in barley, potentially enabling differentiation between wheat and barley. The developed LC/MS-based method was successfully used to analyse ARs extracted from Must Farm potsherds and identified the cereal species most likely processed in the pots?emmer wheat. Conclusion The described method offers an alternative and more sensitive approach for detecting and identifying ARs in ancient pottery. It has been successfully utilised to detect AR homologues in archaeological samples and discriminate which cereal species?wheat and barley?were processed in the pots

Seasonal exploitation of intertidal resources at El Mazo (N Iberia) reveals optimized human subsistence strategies during the Mesolithic in Atlantic Europe

International audienceOver the last few decades, research has significantly enhanced our understanding of the role played by shellfish in human subsistence during the Mesolithic period along the Atlantic coast of Europe. Instrumental to this advance has been the analysis of stable oxygen isotope measurements (delta 18O) from mollusc shells, which offers valuable insights into the seasonality of shellfish exploitation. The delta 18O values serve as reliable indicators of past seasonal seawater temperature variations experienced by the molluscs, enabling us to accurately determine the time of year when past humans collected them. Recent studies using this approach have successfully identified seasonal exploitation patterns of the topshell Phorcus lineatus (da Costa, 1778) in Atlantic Europe. However, uncertainties remain regarding the exploitation schedule of Patella depressa Pennant 1777, one of the most abundantly collected species in Mesolithic sites. Here we used shell delta 18O values of P. depressa from the Mesolithic sites of El Mazo (Northern Iberia) to determine its seasonality of exploitation. Our study reveals that P. depressa was prevalently exploited during colder months. Modern specimens of the same limpet species were also collected during two annual cycles to assess potential seasonal changes in meat yield return. Results obtained has profound implications for better understanding how last coastal foragers managed available littoral resources throughout the year