Publications by authors named "Thibaut Devièse"

21 Publications

  • Page 1 of 1

Dating the last Middle Palaeolithic of the Crimean Peninsula: New hydroxyproline AMS dates from the site of Kabazi II.

J Hum Evol 2021 Jul 18;156:102996. Epub 2021 May 18.

Oxford Radiocarbon Accelerator Unit, RLAHA, Dyson Perrins Building, University of Oxford, OX13QY, Oxford, UK. Electronic address:

Radiocarbon dating of bone and charcoal from sites dating to the Middle and Upper Paleolithic is challenging due to low residual levels of radiocarbon. This means that small amounts of contaminating carbon can wield a great influence over accuracy unless they are fully removed. The site of Kabazi II in the Crimea is important because radiocarbon dates previously obtained from bones in archaeological horizons that date to the Western Crimean Mousterian (WCM) are surprisingly young. We redated the same samples using a single compound dating method that focuses on extracting and dating the amino acid hydroxyproline. We show that single amino acid dates produce significantly older determinations than those that use bulk collagen pretreatment procedures. Our results suggest that instead of dating to 35,000-40,000 cal BP, the bones actually date to >50,000 cal BP. This implies that the WCM at this site is much older than previously thought. In light of these current findings, we considered the dates of other key Crimean sites and concluded that in the absence of reliable pretreatment methods, it would be wise to consider many of them minimum ages. We conclude that there is little robust evidence to suggest Neanderthals were present in the Crimea after 40,000 cal BP.
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http://dx.doi.org/10.1016/j.jhevol.2021.102996DOI Listing
July 2021

A genome sequence from a modern human skull over 45,000 years old from Zlatý kůň in Czechia.

Nat Ecol Evol 2021 06 7;5(6):820-825. Epub 2021 Apr 7.

Max Planck Institute for the Science of Human History, Jena, Germany.

Modern humans expanded into Eurasia more than 40,000 years ago following their dispersal out of Africa. These Eurasians carried ~2-3% Neanderthal ancestry in their genomes, originating from admixture with Neanderthals that took place sometime between 50,000 and 60,000 years ago, probably in the Middle East. In Europe, the modern human expansion preceded the disappearance of Neanderthals from the fossil record by 3,000-5,000 years. The genetic makeup of the first Europeans who colonized the continent more than 40,000 years ago remains poorly understood since few specimens have been studied. Here, we analyse a genome generated from the skull of a female individual from Zlatý kůň, Czechia. We found that she belonged to a population that appears to have contributed genetically neither to later Europeans nor to Asians. Her genome carries ~3% Neanderthal ancestry, similar to those of other Upper Palaeolithic hunter-gatherers. However, the lengths of the Neanderthal segments are longer than those observed in the currently oldest modern human genome of the ~45,000-year-old Ust'-Ishim individual from Siberia, suggesting that this individual from Zlatý kůň is one of the earliest Eurasian inhabitants following the expansion out of Africa.
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http://dx.doi.org/10.1038/s41559-021-01443-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8175239PMC
June 2021

Reevaluating the timing of Neanderthal disappearance in Northwest Europe.

Proc Natl Acad Sci U S A 2021 Mar 8;118(12). Epub 2021 Mar 8.

Oxford Radiocarbon Accelerator Unit, Research Laboratory for Archaeology and the History of Art, University of Oxford, OX1 3QY Oxford, United Kingdom.

Elucidating when Neanderthal populations disappeared from Eurasia is a key question in paleoanthropology, and Belgium is one of the key regions for studying the Middle to Upper Paleolithic transition. Previous radiocarbon dating placed the Spy Neanderthals among the latest surviving Neanderthals in Northwest Europe with reported dates as young as 23,880 ± 240 B.P. (OxA-8912). Questions were raised, however, regarding the reliability of these dates. Soil contamination and carbon-based conservation products are known to cause problems during the radiocarbon dating of bulk collagen samples. Employing a compound-specific approach that is today the most efficient in removing contamination and ancient genomic analysis, we demonstrate here that previous dates produced on Neanderthal specimens from Spy were inaccurately young by up to 10,000 y due to the presence of unremoved contamination. Our compound-specific radiocarbon dates on the Neanderthals from Spy and those from Engis and Fonds-de-Forêt demonstrate that they disappeared from Northwest Europe at 44,200 to 40,600 cal B.P. (at 95.4% probability), much earlier than previously suggested. Our data contribute significantly to refining models for Neanderthal disappearance in Europe and, more broadly, show that chronometric models regarding the appearance or disappearance of animal or hominin groups should be based only on radiocarbon dates obtained using robust pretreatment methods.
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http://dx.doi.org/10.1073/pnas.2022466118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7999949PMC
March 2021

Denisovan ancestry and population history of early East Asians.

Science 2020 10;370(6516):579-583

Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany.

We present analyses of the genome of a ~34,000-year-old hominin skull cap discovered in the Salkhit Valley in northeastern Mongolia. We show that this individual was a female member of a modern human population that, following the split between East and West Eurasians, experienced substantial gene flow from West Eurasians. Both she and a 40,000-year-old individual from Tianyuan outside Beijing carried genomic segments of Denisovan ancestry. These segments derive from the same Denisovan admixture event(s) that contributed to present-day mainland Asians but are distinct from the Denisovan DNA segments in present-day Papuans and Aboriginal Australians.
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http://dx.doi.org/10.1126/science.abc1166DOI Listing
October 2020

Molecular profiling of Peru Balsam reveals active ingredients responsible for its pharmaceutical properties.

Nat Prod Res 2020 Apr 21:1-6. Epub 2020 Apr 21.

Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford, UK.

Peru Balsam, a resinous substance derived from var. , has historically been used as a topical ointment for various skin conditions such as scabies, poorly healing wounds, eczema, and haemorrhoids. The ingredients responsible for these properties are not fully elucidated. We investigated the chemical composition of two Peru Balsam samples, one historical and one modern, using gas chromatography/mass spectrometry to identify the active ingredients responsible for its pharmaceutical properties. Both Peru Balsam specimens investigated had similar compositions, showing the stability of the substance. Components identified are effective against scabies, exhibit antimicrobial activity and aid skin penetration. These properties are consistent with historical uses of Peru Balsam. Several ingredients are also known allergens. This study, combining chemical information with scientific literature related to pharmaceutical properties of natural substances, represents a breakthrough in the elucidation of active ingredients in Peru Balsam.
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http://dx.doi.org/10.1080/14786419.2020.1753056DOI Listing
April 2020

Birch bark tar in early Medieval England - Continuity of tradition or technological revival?

J Archaeol Sci Rep 2020 Feb;29:102118

Organic Geochemistry Unit, School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.

Birch bark tar is a manufactured product with a history of production and use that reaches back to the Palaeolithic. Its sticky, water resistant and biocidal properties mean that it has a wide range of applications, for example, as a multipurpose adhesive, sealant and in medicine. Archaeological evidence for birch bark tar in the old world covers a broad geographic range from the UK to the Baltic and from the Mediterranean to Scandinavia. In the east and north of this range there is continuity of use to modern times but in western Europe and the British Isles the use of birch bark tar has generally been viewed as limited to prehistory, with gradual displacement by pine tars during the Roman period. Here, we report new finds of birch bark tar from two early Medieval sites in the east of England. Analysis by HT-GC/MS to identify the tars also revealed fatty material, possibly added to modify the tar. The different contexts of the finds point to diverse applications of the material: in one case perhaps a medicine, the other associated with a ceramic container, possibly used for processing the tar. The results present the first identification of birch bark tar from early Medieval archaeological contexts in the UK. Together they indicate a later period of use for birch bark tar in the UK than has been previously observed and raise the question of whether this indicates evidence of a longer continuity of use than hitherto recognised or a later reintroduction of the technology in the Medieval period, in which case the similarities between the find sites, both early Anglo-Saxon cemeteries with comparable assemblages of grave goods, may be significant.
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http://dx.doi.org/10.1016/j.jasrep.2019.102118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063695PMC
February 2020

Assessing the efficiency of supercritical fluid extraction for the decontamination of archaeological bones prior to radiocarbon dating.

Analyst 2019 Oct;144(20):6128-6135

Oxford Radiocarbon Accelerator Unit, RLAHA, University of Oxford, 1 South Parks Road, Oxford, OX1 3TG, UK.

Bone is one of the main sample types used for building chronologies in archaeology. It is also used in other research areas such as palaeodiet and palaeoenvironmental studies. However, for results to be accurate, samples must be free of exogenous carbon. Contamination can originate from a wide range of sources in the post-depositional environment but may also occur during excavation and post excavation activities (i.e. with the application of conservation materials) or during laboratory handling. Efficient procedures to remove contamination are therefore crucial prior to radiocarbon or stable isotope measurements. This work describes the development of an innovative sample pretreatment for bones, based on using supercritical CO2, which shows unique solvation properties. The effectiveness of supercritical fluid extraction (SFE) to remove conservation materials was compared with that obtained when applying a routine extraction based on the use of organic solvents (methanol, acetone and chloroform). The chemical composition of the bone samples before and after the two pre-treatments was then investigated using analytical pyrolysis-based techniques: EGA-MS (Evolved Gas Analysis-Mass Spectrometry) and Py-GC/MS (Pyrolysis-Gas Chromatography coupled with Mass Spectrometry). Collagen samples extracted from the same bones, prepared with the two cleaning protocols, were also radiocarbon dated by Accelerator Mass Spectrometry (AMS). The results of this study show that SFE is an efficient alternative method because it was as effective as the established treatment protocol. It removes contaminants such as conservation materials from bone samples with a minimum of handling and can be used routinely in radiocarbon dating laboratories. This work also demonstrates that analytical pyrolysis is not only a very efficient method to identify contaminants in bones but also to assess the effectiveness of the pretreatment prior to the radiocarbon measurement of the samples.
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http://dx.doi.org/10.1039/c9an00859dDOI Listing
October 2019

Preparative HPLC Separation of Underivatized Amino Acids for Isotopic Analysis.

Methods Mol Biol 2019 ;2030:69-83

Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK.

Single-compound analysis of stable or radioactive isotopes has found application in a number of fields ranging from archaeology to forensics. Often, the most difficult part of these analyses is the development of a method for isolating the compound(s) of interest, which can derive from a wide range of sample types including the hair, nails, and bone.Here we describe three complementary preparative HPLC techniques suitable for separating and isolating amino acids from bone collagen and hair keratin. Using preparative reversed-phase, ion-pair, or mixed-mode chromatography in aqueous carbon-free mobile phases, or those from which carbon can easily be removed, underivatized single amino acids can be isolated and further analyzed using mass spectrometric techniques.
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http://dx.doi.org/10.1007/978-1-4939-9639-1_7DOI Listing
April 2020

Metabolomics reveals diet-derived plant polyphenols accumulate in physiological bone.

Sci Rep 2019 05 29;9(1):8047. Epub 2019 May 29.

Department of Chemistry, Mansfield Road, University of Oxford, Oxford, OX1 3TA, UK.

Plant-derived secondary metabolites consumed in the diet, especially polyphenolic compounds, are known to have a range of positive health effects. They are present in circulation after ingestion and absorption and can be sequestered into cells within particular organs, but have rarely been investigated systematically in osteological tissues. However, a small number of polyphenols and similar molecules are known to bind to bone. For example alizarin, a plant derived anthraquinone and tetracycline (a naturally occurring antibiotic), are both absorbed into bone from circulation during bone formation and are used to monitor mineralization in osteological studies. Both molecules have also been identified serendipitously in archaeological human bones derived from natural sources in the diet. Whether an analogous mechanism of sequestration extends to additional diet-derived plant-polyphenols has not previously been systematically studied. We investigated whether a range of diet-derived polyphenol-like compounds bind to bone using untargeted metabolomics applied to the analysis of bone extracts from pigs fed an acorn-based diet. We analysed the diet which was rich in ellagitannins, extracts from the pig bones and surrounding tissue, post-mortem. We found direct evidence of multiple polyphenolic compounds in these extracts and matched them to the diet. We also showed that these compounds were present in the bone but not surrounding tissues. We also provide data showing that a range of polyphenolic compounds bind to hydroxyapatite in vitro. The evidence for polyphenol sequestration into physiological bone, and the range and specificity of polyphenols in human and animal diets, raises intriguing questions about potential effects on bone formation and bone health. Further studies are needed to determine the stability of the sequestered molecules post-mortem but there is also potential for (palaeo)dietary reconstruction and forensic applications.
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http://dx.doi.org/10.1038/s41598-019-44390-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6541599PMC
May 2019

New data for the Early Upper Paleolithic of Kostenki (Russia).

J Hum Evol 2019 02 19;127:21-40. Epub 2018 Dec 19.

School of Archaeology, University of Oxford, 1-2 South Parks Road, Oxford OX1 3UB, UK.

Several questions remain regarding the timing and nature of the Neanderthal-anatomically modern human (AMH) transition in Europe. The situation in Eastern Europe is generally less clear due to the relatively few sites and a dearth of reliable radiocarbon dates. Claims have been made for both notably early AMH and notably late Neanderthal presence, as well as for early AMH (Aurignacian) dispersal into the region from Central/Western Europe. The Kostenki-Borshchevo complex (European Russia) of Early Upper Paleolithic (EUP) sites offers high-quality data to address these questions. Here we revise the chronology and cultural status of the key sites of Kostenki 17 and Kostenki 14. The Kostenki 17/II lithic assemblage shares important features with Proto-Aurignacian material, strengthening an association with AMHs. New radiocarbon dates for Kostenki 17/II of ∼41-40 ka cal BP agree with new dates for the recently excavated Kostenki 14/IVw, which shows some similarities to Kostenki 17/II. Dates of ≥41 ka cal BP from other Kostenki sites cannot be linked to diagnostic archaeological material, and therefore cannot be argued to date AMH occupation. Kostenki 14's Layer in Volcanic Ash assemblage, on the other hand, compares to Early Aurignacian material. New radiocarbon dates targeting diagnostic lithics date to 39-37 ka cal BP. Overall, Kostenki's early EUP is in good agreement with the archaeological record further west. Our results are therefore consistent with models predicting interregional penecontemporaneity of diagnostic EUP assemblages. Most importantly, our work highlights ongoing challenges for reliably radiocarbon dating the period. Dates for Kostenki 14 agreed with the samples' chronostratigraphic positions, but standard pre-treatment methods consistently produced incorrect ages for Kostenki 17/II. Extraction of hydroxyproline from bone collagen using preparative high-performance liquid chromatography, however, yielded results consistent with the samples' chronostratigraphic position and with the layer's archaeological contents. This suggests that for some sites compound-specific techniques are required to build reliable radiocarbon chronologies.
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http://dx.doi.org/10.1016/j.jhevol.2018.11.012DOI Listing
February 2019

Age estimates for hominin fossils and the onset of the Upper Palaeolithic at Denisova Cave.

Nature 2019 01 30;565(7741):640-644. Epub 2019 Jan 30.

Oxford Radiocarbon Accelerator Unit, Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford, UK.

Denisova Cave in the Siberian Altai (Russia) is a key site for understanding the complex relationships between hominin groups that inhabited Eurasia in the Middle and Late Pleistocene epoch. DNA sequenced from human remains found at this site has revealed the presence of a hitherto unknown hominin group, the Denisovans, and high-coverage genomes from both Neanderthal and Denisovan fossils provide evidence for admixture between these two populations. Determining the age of these fossils is important if we are to understand the nature of hominin interaction, and aspects of their cultural and subsistence adaptations. Here we present 50 radiocarbon determinations from the late Middle and Upper Palaeolithic layers of the site. We also report three direct dates for hominin fragments and obtain a mitochondrial DNA sequence for one of them. We apply a Bayesian age modelling approach that combines chronometric (radiocarbon, uranium series and optical ages), stratigraphic and genetic data to calculate probabilistically the age of the human fossils at the site. Our modelled estimate for the age of the oldest Denisovan fossil suggests that this group was present at the site as early as 195,000 years ago (at 95.4% probability). All Neanderthal fossils-as well as Denisova 11, the daughter of a Neanderthal and a Denisovan-date to between 80,000 and 140,000 years ago. The youngest Denisovan dates to 52,000-76,000 years ago. Direct radiocarbon dating of Upper Palaeolithic tooth pendants and bone points yielded the earliest evidence for the production of these artefacts in northern Eurasia, between 43,000 and 49,000 calibrated years before present (taken as AD 1950). On the basis of current archaeological evidence, it may be assumed that these artefacts are associated with the Denisovan population. It is not currently possible to determine whether anatomically modern humans were involved in their production, as modern-human fossil and genetic evidence of such antiquity has not yet been identified in the Altai region.
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http://dx.doi.org/10.1038/s41586-018-0870-zDOI Listing
January 2019

Compound-specific radiocarbon dating and mitochondrial DNA analysis of the Pleistocene hominin from Salkhit Mongolia.

Nat Commun 2019 01 30;10(1):274. Epub 2019 Jan 30.

Oxford Radiocarbon Accelerator Unit, Research Laboratory for Archaeology and the History of Art, University of Oxford, Dyson Perrins Building, South Parks Road, Oxford, OX1 3QY, UK.

A skullcap found in the Salkhit Valley in northeast Mongolia is, to our knowledge, the only Pleistocene hominin fossil found in the country. It was initially described as an individual with possible archaic affinities, but its ancestry has been debated since the discovery. Here, we determine the age of the Salkhit skull by compound-specific radiocarbon dating of hydroxyproline to 34,950-33,900 Cal. BP (at 95% probability), placing the Salkhit individual in the Early Upper Paleolithic period. We reconstruct the complete mitochondrial genome (mtDNA) of the specimen. It falls within a group of modern human mtDNAs (haplogroup N) that is widespread in Eurasia today. The results now place the specimen into its proper chronometric and biological context and allow us to begin integrating it with other evidence for the human occupation of this region during the Paleolithic, as well as wider Pleistocene sequences across Eurasia.
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http://dx.doi.org/10.1038/s41467-018-08018-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6353915PMC
January 2019

Evolution and extinction of the giant rhinoceros Elasmotherium sibiricum sheds light on late Quaternary megafaunal extinctions.

Nat Ecol Evol 2019 01 26;3(1):31-38. Epub 2018 Nov 26.

Department of Earth Sciences, Natural History Museum, London, UK.

Understanding extinction events requires an unbiased record of the chronology and ecology of victims and survivors. The rhinoceros Elasmotherium sibiricum, known as the 'Siberian unicorn', was believed to have gone extinct around 200,000 years ago-well before the late Quaternary megafaunal extinction event. However, no absolute dating, genetic analysis or quantitative ecological assessment of this species has been undertaken. Here, we show, by accelerator mass spectrometry radiocarbon dating of 23 individuals, including cross-validation by compound-specific analysis, that E. sibiricum survived in Eastern Europe and Central Asia until at least 39,000 years ago, corroborating a wave of megafaunal turnover before the Last Glacial Maximum in Eurasia, in addition to the better-known late-glacial event. Stable isotope data indicate a dry steppe niche for E. sibiricum and, together with morphology, a highly specialized diet that probably contributed to its extinction. We further demonstrate, with DNA sequencing data, a very deep phylogenetic split between the subfamilies Elasmotheriinae and Rhinocerotinae that includes all the living rhinoceroses, settling a debate based on fossil evidence and confirming that the two lineages had diverged by the Eocene. As the last surviving member of the Elasmotheriinae, the demise of the 'Siberian unicorn' marked the extinction of this subfamily.
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http://dx.doi.org/10.1038/s41559-018-0722-0DOI Listing
January 2019

Early human dispersals within the Americas.

Science 2018 12 8;362(6419). Epub 2018 Nov 8.

Canadian Museum of History, Gatineau, Québec K1A 0M8, Canada.

Studies of the peopling of the Americas have focused on the timing and number of initial migrations. Less attention has been paid to the subsequent spread of people within the Americas. We sequenced 15 ancient human genomes spanning from Alaska to Patagonia; six are ≥10,000 years old (up to ~18× coverage). All are most closely related to Native Americans, including those from an Ancient Beringian individual and two morphologically distinct "Paleoamericans." We found evidence of rapid dispersal and early diversification that included previously unknown groups as people moved south. This resulted in multiple independent, geographically uneven migrations, including one that provides clues of a Late Pleistocene Australasian genetic signal, as well as a later Mesoamerican-related expansion. These led to complex and dynamic population histories from North to South America.
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http://dx.doi.org/10.1126/science.aav2621DOI Listing
December 2018

The prehistoric peopling of Southeast Asia.

Science 2018 07;361(6397):88-92

Anthropological and Paleoenvironmental Department, Institute of Archaeology, Hanoi, Vietnam.

The human occupation history of Southeast Asia (SEA) remains heavily debated. Current evidence suggests that SEA was occupied by Hòabìnhian hunter-gatherers until ~4000 years ago, when farming economies developed and expanded, restricting foraging groups to remote habitats. Some argue that agricultural development was indigenous; others favor the "two-layer" hypothesis that posits a southward expansion of farmers giving rise to present-day Southeast Asian genetic diversity. By sequencing 26 ancient human genomes (25 from SEA, 1 Japanese Jōmon), we show that neither interpretation fits the complexity of Southeast Asian history: Both Hòabìnhian hunter-gatherers and East Asian farmers contributed to current Southeast Asian diversity, with further migrations affecting island SEA and Vietnam. Our results help resolve one of the long-standing controversies in Southeast Asian prehistory.
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http://dx.doi.org/10.1126/science.aat3628DOI Listing
July 2018

Reassessing the chronology of the archaeological site of Anzick.

Proc Natl Acad Sci U S A 2018 07 18;115(27):7000-7003. Epub 2018 Jun 18.

Oxford Radiocarbon Accelerator Unit, Research Lab for Archaeology and the History of Art, School of Archaeology, University of Oxford, OX1 3TG Oxford, United Kingdom.

Found in 1968, the archaeological site of Anzick, Montana, contains the only known Clovis burial. Here, the partial remains of a male infant, Anzick-1, were found in association with a Clovis assemblage of over 100 lithic and osseous artifacts-all red-stained with ochre. The incomplete, unstained cranium of an unassociated, geologically younger individual, Anzick-2, was also recovered. Previous chronometric work has shown an age difference between Anzick-1 and the Clovis assemblage (represented by dates from two antler rod samples). This discrepancy has led to much speculation, with some discounting Anzick-1 as Clovis. To resolve this issue, we present the results of a comprehensive radiocarbon dating program that utilized different pretreatment methods on osseous material from the site. Through this comparative approach, we obtained a robust chronometric dataset that suggests that Anzick-1 is temporally coeval with the dated antler rods. This implies that the individual is indeed temporally associated with the Clovis assemblage.
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http://dx.doi.org/10.1073/pnas.1803624115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6142201PMC
July 2018

Supercritical Fluids for Higher Extraction Yields of Lipids from Archeological Ceramics.

Anal Chem 2018 02 30;90(4):2420-2424. Epub 2018 Jan 30.

Department of Anthropology and Archaeology, University of South Africa , P.O. Box 392, Unisa 0003, South Africa.

The extraction and study of organic residues from ceramics has been a subject of interest for the last 50 years in archeology and archeological science. Lipids are among the best-preserved organic substances in archeological contexts and can provide information about the diets of ancient populations as well as past environments. Here, we present a method which demonstrates significantly improved extraction of lipids from archeological pots by replacing liquid organic solvents with supercritical fluids. Optimization of the procedure using response surface methodology (RSM) approach showed that, on our system, optimal conditions for supercritical extraction of lipids from synthetic fired clay ceramics could be achieved using carbon dioxide with 16 vol % of cosolvent EtOH-HO (95:5 v/v) in 90 min at a flow rate of 2.3 mL/min, for a pressure of 30 MPa and a temperature of 50 °C. For all reference and archeological samples included in this study, lipid yields obtained by supercritical fluid extraction under these optimal conditions were systematically higher than by conventional solvent extraction. This study also highlighted a variability of the ratio of unsaturated versus saturated fatty acids depending on the extraction method. This can have important implications in the identification of the residue(s). The increased extraction efficiency provided by supercritical fluids, as well as their minimally destructive nature, enable new and refined approaches to residue analysis and dating of archeological ceramics.
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http://dx.doi.org/10.1021/acs.analchem.7b04913DOI Listing
February 2018

New protocol for compound-specific radiocarbon analysis of archaeological bones.

Rapid Commun Mass Spectrom 2018 Mar;32(5):373-379

Oxford Radiocarbon Accelerator Unit, Research Laboratory for Archaeology and the History of Art, University of Oxford, 1-2 South Parks Road, Oxford, OX1 3TG, UK.

Rationale: For radiocarbon results to be accurate, samples must be free of contaminating carbon. Sample pre-treatment using a high-performance liquid chromatography (HPLC) approach has been developed at the Oxford Radiocarbon Accelerator Unit (ORAU) as an alternative to conventional methods for dating heavily contaminated bones. This approach isolates hydroxyproline from bone collagen, enabling a purified bone-specific fraction to then be radiocarbon dated by accelerator mass spectrometry (AMS).

Methods: Using semi-preparative chromatography and non-carbon-based eluents, this technique enables the separation of underivatised amino acids liberated by hydrolysis of extracted bone collagen. A particular focus has been the isolation of hydroxyproline for single-compound AMS dating since this amino acid is one of the main contributors to the total amount of carbon in mammalian collagen. Our previous approach, involving a carbon-free aqueous mobile phase, required a two-step separation using two different chromatographic columns.

Results: This paper reports significant improvements that have been recently made to the method to enable faster semi-preparative separation of hydroxyproline from bone collagen, making the method more suitable for routine radiocarbon dating of contaminated and/or poorly preserved bone samples by AMS. All steps of the procedure, from the collagen extraction to the correction of the AMS data, are described.

Conclusions: The modifications to the hardware and to the method itself have reduced significantly the time required for the preparation of each sample. This makes it easier for other radiocarbon facilities to implement and use this approach as a routine method for preparing contaminated bone samples.
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http://dx.doi.org/10.1002/rcm.8047DOI Listing
March 2018

Ancient genomes show social and reproductive behavior of early Upper Paleolithic foragers.

Science 2017 11 5;358(6363):659-662. Epub 2017 Oct 5.

Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, 1350 Copenhagen, Denmark.

Present-day hunter-gatherers (HGs) live in multilevel social groups essential to sustain a population structure characterized by limited levels of within-band relatedness and inbreeding. When these wider social networks evolved among HGs is unknown. To investigate whether the contemporary HG strategy was already present in the Upper Paleolithic, we used complete genome sequences from Sunghir, a site dated to ~34,000 years before the present, containing multiple anatomically modern human individuals. We show that individuals at Sunghir derive from a population of small effective size, with limited kinship and levels of inbreeding similar to HG populations. Our findings suggest that Upper Paleolithic social organization was similar to that of living HGs, with limited relatedness within residential groups embedded in a larger mating network.
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http://dx.doi.org/10.1126/science.aao1807DOI Listing
November 2017

Direct dating of Neanderthal remains from the site of Vindija Cave and implications for the Middle to Upper Paleolithic transition.

Proc Natl Acad Sci U S A 2017 10 5;114(40):10606-10611. Epub 2017 Sep 5.

Oxford Radiocarbon Accelerator Unit, Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford OX1 3QY, United Kingdom.

Previous dating of the Vi-207 and Vi-208 Neanderthal remains from Vindija Cave (Croatia) led to the suggestion that Neanderthals survived there as recently as 28,000-29,000 B.P. Subsequent dating yielded older dates, interpreted as ages of at least ∼32,500 B.P. We have redated these same specimens using an approach based on the extraction of the amino acid hydroxyproline, using preparative high-performance liquid chromatography (Prep-HPLC). This method is more efficient in eliminating modern contamination in the bone collagen. The revised dates are older than 40,000 B.P., suggesting the Vindija Neanderthals did not live more recently than others across Europe, and probably predate the arrival of anatomically modern humans in Eastern Europe. We applied zooarchaeology by mass spectrometry (ZooMS) to find additional hominin remains. We identified one bone that is Neanderthal, based on its mitochondrial DNA, and dated it directly to 46,200 ± 1,500 B.P. We also attempted to date six early Upper Paleolithic bone points from stratigraphic units G, Fd/d+G and Fd/d, Fd. One bone artifact gave a date of 29,500 ± 400 B.P., while the remainder yielded no collagen. We additionally dated animal bone samples from units G and G-G These dates suggest a co-occurrence of early Upper Paleolithic osseous artifacts, particularly split-based points, alongside the remains of Neanderthals is a result of postdepositional mixing, rather than an association between the two groups, although more work is required to show this definitively.
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http://dx.doi.org/10.1073/pnas.1709235114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5635904PMC
October 2017

First chemical evidence of royal purple as a material used for funeral treatment discovered in a Gallo-Roman burial (Naintré, France, third century AD).

Anal Bioanal Chem 2011 Oct 7;401(6):1739-48. Epub 2011 Jul 7.

Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Pisa, Italy.

Violet-purple residues collected from a Gallo-Roman burial dated back to the second half of the third century A.D. and excavated at Naintré (France) were chemically investigated by multi-analytical methodology involving the use of Raman spectroscopy, direct exposure-mass spectrometry (DE-MS) and high-performance liquid chromatography (HPLC-UV-visible). Little is known about funeral treatment and rituals during Roman times. Retrieving valuable information on these by chemical analysis of organic residues was thus a key aspect of this work. Analyses demonstrated the presence of the very precious purple colorant obtained from shellfish glands commonly known as Tyrian or royal purple and its exceptional preservation. Chemical investigation and archaeological evidence have shown that purple was widely spread after the deposition of the body for burial. These results are the earliest chemical evidence of purple colorant used during funeral rituals (not as textile dye) and enabled us to highlight new aspects of funeral practices in Roman times.
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http://dx.doi.org/10.1007/s00216-011-5217-7DOI Listing
October 2011