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Direct, accurate, and precise dating of archaeological pottery vessels is now achievable using a recently developed approach based on the radiocarbon dating of purified molecular components of food residues preserved in the walls of pottery vessels. The method targets fatty acids from animal fat residues, making it uniquely suited for directly dating the inception of new food commodities in prehistoric populations. Here, we report a large-scale application of the method by directly dating the introduction of dairying into Central Europe by the Linearbandkeramik (LBK) cultural group based on dairy fat residues. The radiocarbon dates ( n = 27) from the 54th century BC from the western and eastern expansion of the LBK suggest dairy exploitation arrived with the first settlers in the respective regions and were not gradually adopted later. This is particularly significant, as contemporaneous LBK sites showed an uneven distribution of dairy exploitation. Significantly, our findings demonstrate the power of directly dating the introduction of new food commodities, hence removing taphonomic uncertainties when assessing this indirectly based on associated cultural materials or other remains.

Direct and accurate radiocarbon dating of lipid residues preserved in ceramics is a recently established method that allows direct dating of specific food products and their inception in human subsistence strategies. The method targets individual fatty acids originating from animal fats such as ruminant dairy, ruminant adipose, non-ruminant adipose and aquatic fats. Horse lipid residues found in Central Asian pottery vessels are also directly dateable using this new method. Here we present the identification of equine lipid residues preserved in two pottery assemblages from the Neolithic and Eneolithic in Kazakhstan and their direct 14C dating. The site of Botai, previously radiocarbon-dated to the 4th millennium BC, was used as a reference to evaluate the dates obtained directly on horse lipids. The direct dating of equine products extracted from Botai potsherds are shown to be compatible with previous 14C dates at the site. The site of Bestamak, lacking previous14C measurements, had been relatively dated to the Neolithic based on pottery typologies. The direct dating of equine residues made it possible to anchor the pottery assemblage of Bestamak in the 6th millennium BC confirming their Neolithic attribution. These findings demonstrate the potential for dating horse products through a compound-specific approach, while highlighting challenges in 14C dating individual fatty acids from lipid extracts in which their abundances differ substantially.

The analysis of processing standards alongside samples for quality assurance in radiocarbon (14C) analyses is critical. Ideally, these standards should be similar both in nature and age to unknown samples. A new compound-specific approach was developed at the University of Bristol for dating pottery vessels using palmitic and stearic fatty acids extracted from within the clay matrix and isolated by preparative capillary gas chromatography. Obtaining suitable potsherds for use as processing standards in such analyses is not feasible, so we suggest that bog butter represents an ideal material for such purposes. We sampled ca. 450 g from two bog butter specimens and homogenized them by melting. We verified the homogeneity of both specimens by characterization of their lipid composition, δ13C values of individual lipids, and both bulk- and compound-specific radiocarbon analyses on 10 sub-samples of each bog butter specimen. The weighted means of all 14C measurements on the bog butter standards are 3777 ± 4 BP (IB33) and 338 ± 3 BP (IB38), thereby providing age-relevant standards for archaeological and historical fatty acids and ensuring the accuracy of radiocarbon determinations of lipids using a compound-specific approach. These new secondary standards will be subjected to an intercomparison exercise to provide robust consensus values.

This article presents the results of the first dedicated study of organic residues in Portugal, extracted from pottery excavated from Anta 1 de Val da Laje passage grave. We fully exploit the organic residue extract, to obtain information regarding the diet of the people and their relationship with the environment, the socio-economic aspects of an otherwise elusive society, and we also used a new methodology to obtain direct absolute dates for the pottery, the residue extract being the only datable organic material from the site. Our results suggest a community with diet based on terrestrial resources, that was fully benefitting from a range of domestic animals including their secondary products. We present the first direct evidence of not only meat consumption, but also milk and dairy production in Iberia. The compound-specific radiocarbon dating methodology, opens a door to possibilities for investigating otherwise poorly dated archaeological phenomena in the Iberian Peninsula.

Stable isotope signatures of domesticates found on archaeology sites provide information about past human behaviour, such as the evolution and adaptation of husbandry strategies. A dynamic phase in cattle husbandry evolution is during the 6th millennium BCE, where the first cattle herders of central Europe spread rapidly through diverse forested ecological niches, where little is known about pasturing strategies. Here we investigate cattle pasturing and foddering practices using a multi-regional dataset of stable isotope values (δ13C and δ18O; compound-specific stable isotopic analysis δ15N-amino acids and δ13C-dairy fats) measured from cattle bone and teeth, and pottery residues from early farming contexts, and palaeoenvironmental information. Our analysis reveals that farmers practiced different pasturing strategies with the intensive use of forested ecosystems in some areas for both graze and seasonal forage. We propose that the diversity of strategies is related to the adaptation of herding to new environments, which had a positive impact on cattle breeding and milk availability for human consumption.

Direct and accurate radiocarbon dating of lipid residues preserved in ceramics is a recently established method that allows direct dating of specific food products and their inception in human subsistence strategies. The method targets individual fatty acids originating from animal fats such as ruminant dairy, ruminant adipose, non-ruminant adipose and aquatic fats. Horse lipid residues found in Central Asian pottery vessels are also directly dateable using this new method. Here we present the identification of equine lipid residues preserved in two pottery assemblages from the Neolithic and Eneolithic in Kazakhstan and their directThe online version contains supplementary material available at 10.1007/s12520-022-01630-2.

In European and many African, Middle Eastern and southern Asian populations, lactase persistence (LP) is the most strongly selected monogenic trait to have evolved over the past 10,000 years1. Although the selection of LP and the consumption of prehistoric milk must be linked, considerable uncertainty remains concerning their spatiotemporal configuration and specific interactions2,3. Here we provide detailed distributions of milk exploitation across Europe over the past 9,000 years using around 7,000 pottery fat residues from more than 550 archaeological sites. European milk use was widespread from the Neolithic period onwards but varied spatially and temporally in intensity. Notably, LP selection varying with levels of prehistoric milk exploitation is no better at explaining LP allele frequency trajectories than uniform selection since the Neolithic period. In the UK Biobank4,5 cohort of 500,000 contemporary Europeans, LP genotype was only weakly associated with milk consumption and did not show consistent associations with improved fitness or health indicators. This suggests that other reasons for the beneficial effects of LP should be considered for its rapid frequency increase. We propose that lactase non-persistent individuals consumed milk when it became available but, under conditions of famine and/or increased pathogen exposure, this was disadvantageous, driving LP selection in prehistoric Europe. Comparison of model likelihoods indicates that population fluctuations, settlement density and wild animal exploitation—proxies for these drivers—provide better explanations of LP selection than the extent of milk exploitation. These findings offer new perspectives on prehistoric milk exploitation and LP evolution.

International audience; The Alsace region bordering the Rhine River was extensively occupied during the Neolithic by farming societies with domesticated animal. The first settlers were two sub-groups of the Linearbandkeramik who appeared to diverge in several respects, including: pottery styles, house orientations and funerary rituals. To explore whether this was reflected in food procurement practices investigations were performed of organic residues in nearly 900 pottery vessels from sites across the region. The results reveal lipid biomarker and stable carbon evidence for exploitation of plant and bee products, and most significantly, extensive domestic animal products including: non-ruminant carcass products, and ruminant primary and secondary products. Critically, culturally-related economic differences were seen spatially between the upper and lower Alsatian groups. Temporal differences were confirmed using compound-specific radiocarbon dating of fatty acids preserved in potsherds, showing that while milk exploitation was widespread during the early Neolithic in UA, it only became commonplace in LA generations later.

International audience; he application of biomolecular techniques to archaeological materials from the Balkans is providing valuable new information on the prehistory of the region. This is especially relevant for the study of the neolithisation process in SE Europe, which gradually affected the rest of the continent. Here, to answer questions regarding diet and subsistence practices in early farming societies in the central Balkans, we combine organic residue analyses of archaeological pottery, taxonomic and isotopic study of domestic animal remains and biomolecular analyses of human dental calculus. The results from the analyses of the lipid residues from pottery suggest that milk was processed in ceramic vessels. Dairy products were shown to be part of the subsistence strategies of the earliest Neolithic communities in the region but were of varying importance in different areas of the Balkan. Conversely, milk proteins were not detected within the dental calculus. The molecular and isotopic identification of meat, dairy, plants and beeswax in the pottery lipids also provided insights into the diversity of diet in these early Neolithic communities, mainly based on terrestrial resources. We also present the first compound-specific radiocarbon dates for the region, obtained directly from absorbed organic residues extracted from pottery, identified as dairy lipids.

The development of pastoralism transformed human diets and societies in grasslands worldwide. The long-term success of cattle herding in Africa has been sustained by dynamic food systems, consumption of a broad range of primary and secondary livestock products, and the evolution of lactase persistence (LP), which allows digestion of lactose into adulthood and enables the milk-based, high-protein, low-calorie diets characteristic of contemporary pastoralists. Despite the presence of multiple alleles associated with LP in ancient and present-day eastern African populations, the contexts for selection for LP and the long-term development of pastoralist foodways in this region remain unclear. Pastoral Neolithic (c. 5000 to 1200 BP) faunas indicate that herders relied on cattle, sheep, and goats and some hunting, but direct information on milk consumption, plant use, and broader culinary patterns is rare. Combined chemical and isotopic analysis of ceramic sherds (n = 125) from Pastoral Neolithic archaeological contexts in Kenya and Tanzania, using compound-specific δ(13)C and Δ(13)C values of the major fatty acids, provides chemical evidence for milk, meat, and plant processing by ancient herding societies in eastern Africa. These data provide the earliest direct evidence for milk product consumption and reveal a history of reliance on animal products and other nutrients, likely extracted through soups or stews, and plant foods. They document a 5,000-y temporal framework for eastern Africa pastoralist cuisines and cultural contexts for selection for alleles distinctive of LP in eastern Africa.

The application of biomolecular techniques to archaeological materials from the Balkans is providing valuable new information on the prehistory of the region. This is especially relevant for the study of the neolithisation process in SE Europe, which gradually affected the rest of the continent. Here, to answer questions regarding diet and subsistence practices in early farming societies, we combine organic residue analyses of archaeological pottery, taxonomic and isotopic study of domestic animal remains and biomolecular analyses of human dental calculus. The results from the analyses of the lipid residues from pottery suggest that milk was processed in ceramic vessels. Dairy products were shown to be part of the subsistence strategies of the earliest Neolithic communities in the region but were of varying importance in different areas of the Balkan. On the other hand, we did not confidently detect any milk proteins within the dental calculus. The molecular and isotopic identification of meat, dairy, plants and beeswax in the pottery lipids also provided insights into the diversity of diet in these early Neolithic communities. We also present the first compound-specific radiocarbon dates for the region, obtained directly on absorbed organic residues extracted from pottery, identified as dairy lipids.

At archaeological sites located on islands or near the coast, the potential exists for lipid extracts of potsherds to contain fatty acids (FA) from both aquatic and terrestrial organisms, meaning that consideration must be given to marine reservoir effects (MRE) in radiocarbon (14C) analyses. Here we studied the site of Bornais (Outer Hebrides, UK) where a local MRE, ΔR of –65 ± 45 yr was determined through the paired 14C determinations of terrestrial and marine faunal bones. Lipid analysis of 49 potsherds, revealed aquatic biomarkers in 45% of the vessels, and δ13C values of C16:0 and C18:0 FAs revealed ruminant and marine product mixing for 71% of the vessels. Compound-specific 14C analysis (CSRA) of FAs yielded intermediate 14C ages between those of terrestrial and marine bones from the same contexts, confirming an MRE existed. A database containing δ13C values for FAs from reference terrestrial and marine organisms provided endmembers for calculating the percentage marine-derived C (%marine) in FAs. We show that lipid 14C dates can be corrected using determined %marine and ΔR values, such that pottery vessels from coastal locations can be 14C dated by CSRA of FAs.

Preparative capillary gas chromatography (pcGC) is widely used for the isolation of single compounds for radiocarbon determinations. While being effective at isolating compounds, there are still genuine concerns relating to contamination associated with the isolation procedure, such as incomplete removal of solvent used to recover isolated compounds from the traps and cross-contamination, which can lead to erroneous 14C determinations. Herein we describe new approaches to identifying and removing these two sources of contamination. First, we replaced the common "U" trap design, which requires recovery of compounds using organic solvent, with a novel solventless trapping system (STS), consisting of a simple glass tube containing a glass wool plug, allowing condensation of a target compound in the wool and its solventless recovery by pushing the glass wool directly into a foil capsule for graphitization. With the STS trap, an average of 95.7% of the target compound was recovered, and contamination from column bleed was reduced. In addition, comparison of 14C determinations of fatty acid methyl ester (FAME) standards determined offline to those isolated by pcGC in STS traps showed excellent reproducibility and accuracy compared to those isolated using the commercial "U" traps. Second, "coldspots" were identified in the instrument, i.e., the termini of capillaries in the preparative unit, which can be cleaned of compounds condensed from earlier runs using a heat gun. Our new procedure, incorporating these two modifications, was tested on archeological fat hoards, producing 14C dates on isolated C16:0 and C18:0 fatty acids statistically consistent with the bulk dates of the archeological material.

Organic residue analyses of archaeological ceramics can provide important insights into ancient foodways. To date, however, there has been little critical reflection on how lipid residues might (or might not) reflect dietary practices or subsistence strategies more generally. A combination of ethnoarchaeological research and chemical and isotopic analyses of lipid residues from pottery made and used by modern Samburu pastoralists in northern Kenya was undertaken to supplement the interpretive framework used in archaeological investigations. A total of 63 potsherds were collected from various contexts, including settlement sites and rockshelters, and analysed using gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) and gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). The results showed that the free fatty acids, palmitic (C16:0) and stearic (C18:0), dominated the lipid profiles, with extremely broad ranges of δ13C values. The majority of the Δ13C values from Samburu pots suggest that vessels were intensively used to process ruminant carcass products, yet the Samburu economy is not, in fact, meat-based at all. Despite an overall reliance on dairy products, milk is rarely processed in ceramic vessels, largely due to cultural prohibitions. Surprisingly, a number of vessels from one site, Naiborkeju Hill, were used to process dairy products. Compound-specific radiocarbon dating of lipids from these sherds suggests that this pottery originated from an earlier period, demonstrating a possible shift in ceramic use by pastoralist communities in this region over time. The overall conclusion is that lipid residues may not necessarily reflect, in a simple way, the day-to-day consumption or the perceived relative importance of different foodstuffs. In the Samburu case, lipid residues reflect the functional and ideological suitability of ceramics for processing only certain types of food (meat/fat/bones), despite an overall reliance on milk. These conclusions are important when considering the origins and development of African pastoralism, for example, as interpreted from the archaeological record.

Pottery is one of the most commonly recovered artefacts from archaeological sites. Despite more than a century of relative dating based on typology and seriation

Bog butters are large white or yellow waxy deposits regularly discovered within the peat bogs of Ireland and Scotland. They represent an extraordinary survival of prehistoric and later agricultural products, comprising the largest deposits of fat found anywhere in nature. Often found in wooden containers or wrapped in animal bladders, they are considered to have been buried intentionally by past farming communities. While previous analysis has determined that Irish bog butters derive from animal fat, their precise characterisation could not be achieved due to diagenetic compositional alterations during burial. Via compound-specific stable isotope analysis, we provide the first conclusive evidence of a dairy fat origin for the Irish bog butter tradition, which differs from bog butter traditions observed elsewhere. Our research also reveals a remarkably long-lived tradition of deposition and possible curation spanning at least 3500 years, from the Early Bronze Age (c. 1700 BC) to the 17th century AD. This is conclusively established via an extensive suite of both bulk and compound-specific radiocarbon dates.

Preparative capillary gas chromatography (PCGC) is the central technique used for the purification of volatile or semi-volatile organic compounds for radiocarbon analysis using accelerator mass spectrometry (AMS). While thicker film columns offer efficient separations, column bleed of cyclic poly(dimethyl siloxane) (PDMS) stationary phase has been highlighted as a potential source of contaminant carbon in ‘trapped’ compounds. The dimethylpolysiloxane CH3 groups are of ‘infinite’ radiocarbon age due to the fossil carbon origin of the feedstock used in production. Hence, column bleed, if present at sufficiently high concentrations, would shift the radiocarbon ages of trapped compounds to older ages. Quantification of the column bleed in trapped samples, however, is extremely challenging and up to now has only been achieved through indirect 14C determinations of chromatographic blanks, which are used for post 14C determination ‘corrections’. As part of wider investigations aimed at better understanding the chemical nature of contamination in compound-specific 14C-determinations, herein, we report a rigorous approach to column bleed identification and quantification. Using reference fatty acid methyl esters (FAMEs) 1H nuclear magnetic resonance spectroscopy (NMR), employing a 700 MHz instrument equipped with a 1.7 mm microcryoprobe optimised for 1H observation, was able to detect low sub-microgram amounts of low molecular weight compounds (

The investigation of organic residues associated with archaeological pottery using modern analytical chemical methods began in the 1970s. It was recognised early on that the analysis of lipids (i.e. fats, waxes and resins) preserved in surface residues or the fabric of single potsherds, representative of single vessels, was a powerful method for ascertaining pottery use, with a high degree of specificity. Subsequent developments saw a significant change in scale, with studies often involving lipid analyses of tens to hundreds of potsherds per archaeological assemblage, providing information that extended beyond pottery use. The identification of animal and plant foodstuffs processed in pots provides insights into herding and farming, and can also detect trade in exotic organic goods. Information about the environment and climate can be extrapolated from the isotopic composition of compounds detected in potsherds, potentially providing novel avenues of investigation. The direct dating of lipids in potsherds is opening up new opportunities for building archaeological chronologies, while the integration of lipid residue analyses with other environmental and cultural proxies within interdisciplinary projects is already providing unprecedented insights into past lifestyles, from site to regional scales.

The recovery of Early Iron Age artefacts and domestic animal remains from hunter-gatherer contexts at Likoaeng, Lesotho, has been argued to indicate contact between highland hunter-gatherers and Early Iron Age agropastoralist communities settled in lowland areas of southeastern Africa during the second half of the first millennium ad. However, disagreement between archaeozoological studies and ancient DNA means that the possibility that those hunter-gatherers kept livestock themselves remains controversial. Here we report analyses of pottery-absorbed organic residues from two hunter-gatherer sites and one agriculturalist site in highland Lesotho to reconstruct prehistoric subsistence practices. Our results demonstrate the exploitation of secondary products from domestic livestock by hunter-gatherers in Lesotho, directly dated to the seventh century ad at Likoaeng and the tenth century ad at the nearby site of Sehonghong. The data provide compelling evidence for the keeping of livestock by hunter-gatherer groups and their probable incorporation as ancillary resources into their subsistence strategies. Fewlass et al. recover dairy residues from hunter-gatherer pottery from highland Lesotho dating from mid-to-late first millennium ad, which implies ongoing contact between these groups and coastal agriculturalists not long after they first arrived in southern Africa.

Pottery is one of the most commonly recovered artefacts from archaeological sites. Despite more than a century of relative dating based on typology and seriation1, accurate dating of pottery using the radiocarbon dating method has proven extremely challenging owing to the limited survival of organic temper and unreliability of visible residues2–4. Here we report a method to directly date archaeological pottery based on accelerator mass spectrometry analysis of 14C in absorbed food residues using palmitic (C16:0) and stearic (C18:0) fatty acids purified by preparative gas chromatography5–8. We present accurate compound-specific radiocarbon determinations of lipids extracted from pottery vessels, which were rigorously evaluated by comparison with dendrochronological dates9,10 and inclusion in site and regional chronologies that contained previously determined radiocarbon dates on other materials11–15. Notably, the compound-specific dates from each of the C16:0 and C18:0 fatty acids in pottery vessels provide an internal quality control of the results6 and are entirely compatible with dates for other commonly dated materials. Accurate radiocarbon dating of pottery vessels can reveal: (1) the period of use of pottery; (2) the antiquity of organic residues, including when specific foodstuffs were exploited; (3) the chronology of sites in the absence of traditionally datable materials; and (4) direct verification of pottery typochronologies. Here we used the method to date the exploitation of dairy and carcass products in Neolithic vessels from Britain, Anatolia, central and western Europe, and Saharan Africa. Using lipid residues absorbed in potsherds, the ages of pottery from various archaeological sites are determined and validated using sites for which the dates are well known from other methods.

International audience