Les nouveaux marqueurs isotopiques de l’alimentation (δ66Zn, δ44Ca, δ15NAA, δ13CAA) et la diversité des stratégies de subsistance néandertaliennes

Cette étude examine les stratégies alimentaires néandertaliennes à l’aide de nouveaux marqueurs isotopiques. Alors que l’analyse isotopique du collagène suggère généralement un régime néandertalien principalement carnivore et terrestre, d’autres méthodes mettent en évidence une consommation occasionnelle de plantes et de ressources aquatiques. Les avancées technologiques récentes introduisent des marqueurs tels que les isotopes du zinc et du calcium dans l’émail dentaire, ainsi que les isoto..

Les isotopes des métaux de transition (Cu, Fe, Zn) au service de l'anthropologie

First developed in geochemistry, isotopic analyses have progressively become a classical tool in anthropology since the seventies. They provide supplementary metabolic information to osteology, such as mobility or diet of past populations. However, isotopic studies only concern six elements among the thirty of the human body. Therefore, other elements could supply information on sex, age-at-death or fecundity, which still are crucial issues in anthropology.The aim of this thesis is to understand the origin of copper, iron and zinc isotopic variability in the human body, and to assess the contribution of these elements for anthropology. In order to do this, metals were purified from sample matrix by liquid chromatography on ion exchange resin and the isotope compositions were measured by multiple-collector inductively-coupled plasma mass spectrometry (MC-ICP-MS). δ56Fe and δ65Cu analyses performed on phalanx of skeletons coming from a french cementery (Saint-Laurent de Grenoble) revealed an isotopic sex difference which mirrors the one found in blood. Concerning its origin, calculations and data obtained on dental enamel support the hypothesis that the isotopic sex difference is due to a higher metal hepatic solicitation for women rather than differential intestinal absorption between men and women. Blood isotopic data from French and Yakut population also highlighted three other significant factors of variability: menopause, age, and cold stress. Our results argue for the development of Fe, Cu, and Zn stable isotope analyses in human remains as a potential vehicle for information on age-at-death, age at menopause, sex and metabolic adaptation to cold stress of past populations.Depuis les années soixante-dix, l’outil isotopique, d’abord développé en géochimie, s’est généralisé en anthropologie. Il est en effet susceptible d’apporter des informations métaboliques complémentaires à l’étude ostéologique, notamment sur la mobilité et l’alimentation des populations passées. Cependant, sur la trentaine d’éléments présente dans le corps humain, seuls six d’entre eux sont classiquement étudiés dans les ossements. Dès lors, les isotopes stables d’autres éléments représentent une source d’informations inexploitée. Ils pourraient effectivement contribuer aux questions cruciales que sont la diagnose sexuelle, l’estimation de la fécondité ou encore l’évaluation de l’âge au décès.Le but de ce travail de thèse est de comprendre l’origine de la variabilité isotopique du cuivre, du zinc et du fer dans le corps humain, et ainsi, d’évaluer l’apport potentiel de ces métaux de transition à l’anthropologie. Pour cela, les éléments ont été séparés par chromatographie sur résine échangeuse d’ions. Puis les rapports isotopiques ont été mesurés par spectrométrie de masse à source plasma et à multicollection (MC-ICP-MS).L’analyse du δ56Fe et δ65Cu de phalanges de squelettes du XVII-XVIIIèmes siècles provenant de Saint-Laurent de Grenoble a permis de mettre en évidence une différence isotopique entre hommes et femmes, reflet de celle observée dans le sang. Cette dissemblance isotopique est discutée à partir d’un modèle mathématique s’appuyant sur nos analyses du foie et de l’émail dentaire. Celui-ci nous a amenés à mettre en cause le rôle de la sollicitation hépatique dans la composition isotopique du sang plutôt que celui de l’absorption intestinale. L’étude du δ56Fe, δ65Cu et δ66Zn dans le sang d’une population française et d’une population yakoute a également contribué à dégager trois autres facteurs significatifs de variabilité isotopique : la ménopause, l’âge et le stress thermique.Nos résultats sont donc en faveur du développement de l’analyse des isotopes stables du Fe, Cu et Zn des restes humains en tant que vecteur potentiel d’informations sur leur âge au décès, âge à la ménopause, sexe et adaptation métabolique au froid

Sampling Plants and Malacofauna in 87Sr/86Sr Bioavailability Studies : implications for isoscape mapping and reconstructing of past mobility patterns

Acknowledgments: We thank Annabell Reiner and Sven Steinbrenner (MPI-EVA) for technical and practical support with preparation and analysis of samples. We thank the La Ferrassie Team for support during field sampling and project development, especially Harold Dibble, Shannon McPherron (MPI-EVA), Teresa Steele (UC Davies), Vera Aldeias (MPI-EVA, University of Algarve), Paul Goldberg (University of Wollongong, University Tübingen), Dennis Sandgathe (Simon Fraser University, University of Pennsylvania), Alain Turq (Musée national de Préhistoire, CNRS), and Jean-Jacques Hublin (MPI-EVA), as well as Mike Richards (SFU). Special thanks to Daphne Katranides and Aaron Katranides. We also thank the editor (TP) and two reviewers whose constructive comments greatly improved this manuscript. Funding: This research was funded by the Max Planck Society and a Leverhulme Trust grant to KB (RPG-2017-410), with additional support from Australian Research Council Discovery grants DP0664144 and DP110101417 to RG. KJ thanks the ERC ARCHEIS 803676, and IM thanks Australian Research Council Discovery Early Career Award (DE160100703), for salary support during production of this manuscript.Peer reviewedPublisher PD

Tracing intensive fish and meat consumption using Zn isotope ratios: evidence from a historical Breton population (Rennes, France)

International audienceHere we report Sr and Zn isotope ratios of teeth of medieval to early modern Breton people a population whose diet is known from historical, archeological and collagen isotope data. Most of the population, buried in the Dominican convent of Rennes, France, consists of parliamentary nobles, wealthy commoners and ecclesiastics, who had a diet rich in animal products. Our aim is to assess how the Zn isotope ratios of their teeth compare to those of other French historical populations previously studied, which were characterized by cereal-based diets, and those of modern French individuals, who daily eat animal products. We describe a clear offset (∼0.35‰) between local and non-local human individuals in Zn isotope ratios. The δ 66 Zn tooth values of local individuals overlap that of modern French people, and are lower than those of local carnivores. Non-local δ 66 Zn values are similar to those of historical individuals analyzed previously. We conclude the lower Zn isotope ratios of local humans relative to the associated fauna can be explained by the consumption of carnivorous fish and pork, in agreement with historical, zooarchaeological and collagen (C, N, S) isotope data. Zn isotopes could therefore be a tracer of fish and/or substantial meat consumption in ancient populations

Strontium Isotope Evidence for Neanderthal and Modern Human Mobility at the Upper and Middle Palaeolithic Site of Fumane Cave (Italy)

To investigate the mobility patterns of Neanderthals and modern humans in Europe during the Middle-to-Upper Palaeolithic transition period, we applied strontium isotope analysis to Neanderthal (n = 3) and modern human (n = 2) teeth recovered from the site of Fumane Cave in the Monti Lessini region of Northern Italy. We also measured a large number of environmental samples from the region, to establish a strontium ‘baseline’, and also micromammals (vole teeth) from the levels associated with the hominin teeth. We found that the modern humans and Neanderthals had similar strontium isotope values, and these values match the local baseline values we obtained for the site and the surrounding region. We conclude that both groups were utilizing the local mountainous region where Fumane Cave is situated, and likely the nearby Lessini highlands and Adige plains, and therefore the strontium evidence does not show differening mobility patterns between Neanderthals and modern humans at the Fumane site

Sampling Plants and Malacofauna in 87Sr/86Sr Bioavailability Studies: Implications for Isoscape Mapping and Reconstructing of Past Mobility Patterns

Establishing strontium isotope (87Sr/86Sr) geographical variability is a key component of any study that seeks to utilize strontium isotopes as tracers of provenance or mobility. Although lithological maps can provide a guideline, estimations of bioavailable 87Sr/86Sr are often necessary, both in qualitative estimates of local strontium isotope "catchments" and for informing/refining isoscape models. Local soils, plants and/or animal remains are commonly included in bioavailability studies, although consensus on what (and how extensively) to sample is lacking. In this study, 96 biological samples (plants and snails) were collected at 17 locations spanning 6 lithological units, within a region of south-west France and an area with a high concentration of Paleolithic archaeological sites. Sampling sites aligned with those from a previous study on soil bioavailable strontium, and comparison with these values, and the influence of environmental and anthropogenic variables, was explored. Data confirm a broad correspondence of plant and snail 87Sr/86Sr values with lithological unit/soil values, although the correlation between expected 87Sr/86Sr values from lithology and bioavailable 87Sr/86Sr ratios from biological samples was higher for plants than for snails. Grass, shrub and tree 87Sr/86Sr values were similar but grasses had a stronger relationship with topsoil values than trees, reflecting differences in root architecture. Variability in 87Sr/86Sr ratios from all plant samples was lower for sites located on homogeneous geological substrates than for those on heterogeneous substrates, such as granite. Among environmental and anthropogenic variables, only an effect of proximity to water was detected, with increased 87Sr/86Sr values in plants from sites close to rivers originating from radiogenic bedrock. The results highlight the importance of analyzing biological samples to complement, inform and refine strontium isoscape models. The sampling of plants rather than snails is recommended, including plants of varying root depth, and (if sample size is a limitation) to collect a greater number of samples from areas with heterogeneous geological substrates to improve the characterizations of those regions. Finally, we call for new experimental studies on the mineralized tissues of grazers, browsers, frugivores and/or tree leaf feeders to explore the influence of 87Sr/86Sr variability with soil profile/root architecture on 87Sr/86Sr values of locally-feeding fauna.This research was funded by the Max Planck Society and a Leverhulme Trust grant to KB (RPG-2017-410), with additional support from Australian Research Council Discovery grants DP0664144 and DP110101417 to RG. KJ thanks the ERC ARCHEIS 803676, and IM thanks Australian Research Council Discovery Early Career Award (DE160100703), for salary support during production of this manuscript

Reply to Ben-Dor and Barkai: A low Zn isotope ratio is not equal to a low Zn content

However, we are afraid that there was a misunderstanding in the interpretation of our data. Ben-Dor and Barkai (2) wrote that "One explanation presented in the [our] paper was that Neandertals may have consumed body parts and animals that were relatively poor in zinc, like the liver or deer." This sentence is not reflecting our conclusions: We discussed Zn isotope ratios (i.e., 66Zn/64Zn ratio expressed as a δ66Zn value) and not Zn concentrations. To explain low δ66Zn values of the Neandertal tooth, we propose that Neandertals ate food items depleted in heavy Zn isotopes (and therefore enriched in light Zn isotopes), but those foods can have variable Zn contents, independent of the Zn isotope composition as such

Les premières preuves isotopiques d’une forte consommation de plantes chez les chasseurs-cueilleurs du Pléistocène supérieur à Taforalt, Maroc

La transition des stratégies de subsistance des chasseurs-cueilleurs vers l’agropastoralisme représente l’une des évolutions alimentaires les plus significatives de l’évolution humaine, mais qui reste cependant encore peu documentée en Afrique du Nord. Le site de Taforalt (Maroc) est l’une des plus anciennes nécropoles de cette région datant de la période ibéromaurusienne (15000-13000 cal BP). La présence de caries dentaires sur les individus inhumés ainsi que les preuves de développement d’..

Trophic position of Otodus megalodon and great white sharks through time revealed by zinc isotopes

Diet is a crucial trait of an animal’s lifestyle and ecology. The trophic level of an organism indicates its functional position within an ecosystem and holds significance for its ecology and evolution. Here, we demonstrate the use of zinc isotopes (δ66Zn) to geochemically assess the trophic level in diverse extant and extinct sharks, including the Neogene megatooth shark (Otodus megalodon) and the great white shark (Carcharodon carcharias). We reveal that dietary δ66Zn signatures are preserved in fossil shark tooth enameloid over deep geologic time and are robust recorders of each species’ trophic level. We observe significant δ66Zn differences among the Otodus and Carcharodon populations implying dietary shifts throughout the Neogene in both genera. Notably, Early Pliocene sympatric C. carcharias and O. megalodon appear to have occupied a similar mean trophic level, a finding that may hold clues to the extinction of the gigantic Neogene megatooth shark.publishedVersio

Isotopic evidence of high reliance on plant food among Later Stone Age hunter-gatherers at Taforalt, Morocco

The transition from hunting-gathering to agriculture stands as one of the most important dietary revolutions in human history. Yet, due to a scarcity of well-preserved human remains from Pleistocene sites, little is known about the dietary practices of pre-agricultural human groups. Here we present the isotopic evidence of pronounced plant reliance among Late Stone Age hunter-gatherers from North Africa (15,000–13,000 cal BP), predating the advent of agriculture by several millennia. Employing a comprehensive multi-isotopic approach, we conducted zinc (δ66Zn) and strontium (87Sr/86Sr) analysis on dental enamel, bulk carbon (δ13C) and nitrogen (δ15N) and sulfur (δ34S) isotope analysis on dentin and bone collagen, and single amino acid analysis on human and faunal remains from Taforalt (Morocco). Our results unequivocally demonstrate a substantial plant-based component in the diets of these hunter-gatherers. This distinct dietary pattern challenges the prevailing notion of high reliance on animal proteins among pre-agricultural human groups. It also raises intriguing questions surrounding the absence of agricultural development in North Africa during the early Holocene. This study underscores the importance of investigating dietary practices during the transition to agriculture and provides insights into the complexities of human subsistence strategies across different regions