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International audience; Following a thematic day on “Service and expertise through archaeological and conservation sciences” organised by the CAI-RN network (Competences Archéométriques Interdisciplinaires - Réseau National, MITI CNRS), the members of the Steering Committee of the CAI-RN network who took part in this workshop wished to bring together and clarify in this text a certain number of the points raised during the discussion. In particular, it gives a brief definition of the terms ‘service’ and ‘expertise’ and presents the different types of structures linked to the archaeometric community and carrying out these activities. This proposal for an initial analysis of the current situation also suggests a number of thought-provoking impulses.; Suite à une journée thématique « Service et expertise par les sciences archéologiques et de la conservation » organisée par le réseau CAI-RN (Compétences Archéométriques Interdisciplinaires – Réseau National, MITI CNRS) les membres du Comité de Pilotage du réseau CAI-RN ayant participé à cette journée ont souhaité rassembler et clarifier dans ce texte un certain nombre des points évoqués lors des discussions. Ceci en donnant notamment une brève définition des termes « service » et « expertise » et en présentant les différents types de structures liées à la communauté archéométrique et réalisant ces activités. Cette proposition d’une première analyse de la situation actuelle propose aussi quelques pistes de réflexion.

International audience; Paleogenomics makes possible to follow human migrations by DNA analysis of human tissues or teeth and thus the discovery of Denisovans, contemporaries of Neanderthals, mixed with homo sapiens.; La paléogénomie permet de suivre les migrations humaines par l’analyse ADN des tissus humains ou des dents et ainsi la découverte des Dénisoviens, contemporains des Néandertaliens, métissés avec l’homo sapiens.

International audience; In the middle of the 1980s, extraction and analysis of DNA preserved in biologicalremains of the past yielded the first results, giving rise to a new scientific field, paleogenetics.Its first successes were obtained thanks to the advent of PCR. Yet, the degraded nature ofancient DNA and the power of PCR also led to numerous artefacts owing to contamination withmodern DNA that have almost killed this new field at the end of the 1990s. Strict experimentalprocedures and the development of methods of decontamination and contamination preventionallowed the revival of the field. Recently, genome-wide analyses; Au milieu des années 1980, l’extraction et l’analyse de l’ADN préservé dans des ves-tiges biologiques du passé ont donné des premiers résultats, entérinant la naissance du domainede la paléogénétique. C’est grâce à l’invention de la PCR que cette nouvelle discipline a puévoluer et récolter ses premiers succès. Néanmoins, la nature dégradée de l’ADN ancien et lapuissance de la méthode de la PCR ont aussi abouti à de nombreux artefacts dus à la conta-mination avec l’ADN moderne qui ont failli tuer ce nouveau domaine à la fin des années 1990.L’application de procédures expérimentales rigoureuses et le développement de méthodes dedécontamination et de prévention des contaminations ont ensuite permis la renaissance de lapaléogénétique avant que le séquenc¸age massivement parallèle n’ait rendu possible l’obtentiond’information génomique d’individus anciens et l’essor du domaine.

Mithilfe der Paläogenetik können potentiell sowohl die einstige genetische Vielfalt von Arten und/oder Populationen als auch evolutionäre Prozesse aufgedeckt werden, die andernfalls verborgen blieben, verließe man sich nur auf moderne genetische Daten. Nach einer generellen Darstellung von Grenzen und Potential der Paläogenetik präsentieren wir eine Reihe von Studien aus unserem Labor, die es erlauben, die Entwicklung der genetischen Vielfalt von diversen Tierarten seit dem Ende des Pleistozäns vergleichend zu betrachten - Spezies, die jeweils unterschiedliche Bindungen zum Menschen besaßen, entweder im Zuge der Domestikation oder durch die Vermeidung derselben. Wir zeigen auf, dass obwohl in den Domestizierungsprozess ursprünglich nur ein Teil einer größeren Wildtierpopulation einbezogen wurde, durch den regulären Genfluss von den Wild- zu den Haustieren letztgenannte eine höhere genetische Diversität innehaben als die Wildpopulationen. Denn viele davon haben während des Holozäns eine durch den Menschen verursachte Schrumpfung ihrer Bestände erfahren., Palaeogenetics has the potential to reconstruct past genetic diversity of species and/or populations and to reveal evolutionary processes that would otherwise remain hidden when relying only on modern genetic data. After a general presentation of the limits and potentials of palaeogenetics, we summarize a series of studies from our lab that allow us to compare the evolution of genetic diversity of various animal species since the end of the Pleistocene, that have had different relationships with humans with respect to their domestication or avoidance therefrom. We show that, even though domestication initially involved only a subset of a larger wild population, regular gene flow from wild to domestic animals allowed the latter to retain a higher genetic diversity than related wild populations many of which experienced a severe, human-driven population reduction during the Holocene.

La domestication des bœufs au Néolithique et leur diffusion ont été étudiées aussi bien par l’archéologie et l’archéozoologie que par la phylogénie moléculaire. Toutefois, ces approches très différentes, ayant chacune des contraintes et limites spécifiques, n’ont pas permis l’élaboration d’un modèle unique intégrant l’ensemble des données. Une troisième approche pourrait permettre d’établir un pont entre archéozoologie et phylogénie moléculaire et de résoudre un certain nombre de points controversés : c’est la paléogénétique qui analyse directement l’ADN conservé dans les fossiles. Cette approche est délicate et exigeante, mais apporte le complément indispensable aux autres approches. C’est pour cette raison que nous réalisons une étude paléogénétique de la domestication des bœufs en France. Nos premiers résultats montrent que des bœufs néolithiques domestiqués en Charente ont, comme les bœufs européens actuels, une origine proche-orientale. De plus, nos données préliminaires suggèrent une influence génétique des aurochs locaux dans ce cheptel bovin. Die Domestizierung von Rindern und ihre Verbreitung während der Jungsteinzeit wurden sowohl von Archäologie und Archäozoologie als auch von Molekularer Phylogenie untersucht. Diese verschiedenen Ansätze mit den ihnen eigenen Grenzen und Beschränkungen führten bis heute nicht zur Erstellung eines alle Ergebnisse vereinigenden Modells. Ein dritter Ansatz soll eine Brücke zwischen Archäozoologie und Molekularer Phylogenie bauen und eine Reihe von Widersprüchen lösen: Es handelt sich um die Paläogenetik, die direkt die in Fossilien erhaltene DNS studiert. Obwohl dieser Ansatz technisch sehr schwierig ist und hohe Anforderungen stellt, so ergänzt er doch die zwei anderen Ansätzen auf ideale Weise und ist daher unentbehrlich. Wir führen daher eine paläogenetische Studie des Domestizierungsprozess von Rindern in Frankreich durch. Unsere ersten Ergebnisse zeigen, dass neolithische Hausrinder aus dem Gebiet der Charente denselben nahöstlichen Ursprung haben wie unsere rezenten europäischen Rinder. Darüber hinaus deuten unsere vorläufigen Ergebnisse an, dass lokale Auerochsen auf diesen neolithischen Rinderbestand genetisch Einfluss genommen haben. Both archaeology/archaeozoology and molecular phylogeny have studied the domestication of cattle and the diffusion during the Neolithic period. However, these different approaches with their different intrinsic limits and specific constraints and biases have not converged into a single model unifying all the data obtained so far. A third approach could establish a bridge between archaeozoology and molecular phylogeny and solve a number of controversial questions: this is palaeogenetics analysing directly the DNA preserved in fossils. Although this approach is delicate and demanding, it brings about the indispensable complement to the other approaches. Therefore, we are carrying out a palaeogenetic study of the domestication process of cattle in France. Our first results show the same Near-Eastern origin for the Neolithic domesticated cattle in Charente as for the extant European cattle. Moreover, our preliminary results suggest that the local aurochs had a genetic impact on this Neolithic bovine life-stock.

Taxonomic over-splitting of extinct or endangered taxa, due to an incomplete knowledge of both skeletal morphological variability and the geographical ranges of past populations, continues to confuse the link between isolated extant populations and their ancestors. This is particularly problematic with the genus Equus. To more reliably determine the evolution and phylogeographic history of the endangered Asiatic wild ass, we studied the genetic diversity and inter-relationships of both extinct and extant populations over the last 100,000 years, including samples throughout its previous range from Western Europe to Southwest and East Asia. Using 229 bp of the mitochondrial hypervariable region, an approach which allowed the inclusion of information from extremely poorly preserved ancient samples, we classify all non-African wild asses into eleven clades that show a clear phylogeographic structure revealing their phylogenetic history. This study places the extinct European wild ass, E. hydruntinus, the phylogeny of which has been debated since the end of the 19th century, into its phylogenetic context within the Asiatic wild asses and reveals recent mitochondrial introgression between populations currently regarded as separate species. The phylogeographic organization of clades resulting from these efforts can be used not only to improve future taxonomic determination of a poorly characterized group of equids, but also to identify historic ranges, interbreeding events between various populations, and the impact of ancient climatic changes. In addition, appropriately placing extant relict populations into a broader phylogeographic and genetic context can better inform ongoing conservation strategies for this highly-endangered species., Hem iskelet morfolojik değişkenliği hem de geçmiş popülasyonların coğrafi aralıkları hakkındaki eksik bilgi nedeniyle, nesli tükenmiş veya nesli tükenmekte olan taksonların taksonomik aşırı bölünmesi, izole edilmiş mevcut popülasyonlar ve onların ataları arasındaki bağlantıyı karıştırmaya devam ediyor. Bu özellikle Equus cinsi için sorunludur. Nesli tükenmekte olan Asya yaban eşeği evrimini ve filocoğrafik tarihini daha güvenilir bir şekilde belirlemek için, Batı Avrupa'dan Güneybatıya ve Doğu'ya kadar önceki aralıktaki örnekler de dahil olmak üzere, son 100.000 yılda hem soyu tükenmiş hem de mevcut popülasyonların genetik çeşitliliğini ve karşılıklı ilişkilerini inceledik. Asya. Aşırı derecede kötü korunmuş antik örneklerden gelen bilgilerin dahil edilmesine izin veren bir yaklaşım olan mitokondriyal hiperdeğişken bölgenin 229 bp'sini kullanarak, tüm Afrika dışı yabani eşekleri filogenetik geçmişlerini açığa çıkaran net bir filocoğrafik yapı gösteren on bir sınıfa ayırıyoruz. Bu çalışma, soyoluşu 19. yüzyılın sonundan beri tartışılan, soyu tükenmiş Avrupa yaban eşeği E. hydruntinus'u Asya yaban eşeği içindeki filogenetik bağlamına yerleştiriyor ve şu anda ayrı türler olarak kabul edilen popülasyonlar arasındaki son mitokondriyal introgresyonu ortaya koyuyor. Bu çabalardan kaynaklanan soyların filocoğrafik organizasyonu, yalnızca kötü bir şekilde karakterize edilmiş bir eşitler grubunun gelecekteki taksonomik tespitini geliştirmek için değil, aynı zamanda tarihi aralıkları, çeşitli popülasyonlar arasındaki melezleşen olayları ve eski iklim değişikliklerinin etkisini belirlemek için de kullanılabilir. Ek olarak, mevcut kalıntı popülasyonları daha geniş bir filocoğrafik ve genetik bağlama uygun şekilde yerleştirmek, nesli tükenmekte olan bu türler için devam eden koruma stratejilerini daha iyi bilgilendirebilir.