Sonja Kroll

Julio Bendezu-Sarmiento

Johanna Lhuillier

Élise Luneau

Kai Kaniuth

Mike Teufer

Samariddin Mustafakulov

Mutalib Khasanov

Natalia Vinogradova

Nona Avanesova

Denis Fiorillo

Margareta Tengberg

Arash Sharifi

Céline Bon

Delphine Bosch

Marjan Mashkour
email: marjan.mashkour@mnhn.fr

Mobility and land use in the Greater Khorasan Civilization: Isotopic approaches (87Sr/86Sr, δ18O) on human populations from southern Central Asia

Keywords: 87 Sr/ 86 Sr and δ 18 O isotopes, southern Central Asia, Greater Khorasan Civilization (GKC), human mobility curation, formal analysis, investigation, methodology, project administration, conceptualization, visualization, writing -

des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Introduction

During the Middle and Late Bronze Age, the emergence of complex societies is observed in southern Central Asia. With the rise of the Greater Khorasan Civilization (hereafter GKC 1 , ca. 2400-1500 BCE, e.g., Lyonnet, Dubova 2021) major transformations led to deep cultural and economic shifts.

Archaeological remains evidence the establishment of intensive trade networks and long-distance interactions (cf. e.g., [START_REF] Hiebert | Origins of the Bronze Age Oasis Civilization in Central Asia[END_REF][START_REF] Possehl | The Middle Asian interaction sphere. Trade and contact in the 3rd Millenium BC[END_REF][START_REF] Frachetti | Central Asia, the Steppe, and the Near East, 2500-1500 BC[END_REF]. The location between harsh deserts and high mountain ranges was a natural passage since Neolithic periods (Thomalsky et al. 2013), which later developed into the Silk Road (historical Great Khorasan Road, cf. e.g., [START_REF] De La Vaissière | Central Asia and the Silk Road[END_REF][START_REF] Wilkinson | Tying the Threads of Eurasia[END_REF]. Due to the prevailing climatic conditions, structural migrations such as pastoralism or nomadism to access natural and economic resources, were always essential subsistence strategies of the communities who settled in this region (e.g., [START_REF] Mashkour | Sociétés pastorales et économies de subsistance au Nord Est de l'Iran et au Sud du Turkménistan. In: Bendezu-Sarmiento J (ed) L'archéologie française en Asie centrale[END_REF][START_REF] Spengler | Agriculturalists and pastoralists: Bronze Age economy of the Murghab alluvial fan, southern Central Asia[END_REF].

Hence, the impact of migration and of changes in land use and territorial management remains a matter of ongoing discussions among scientists (cf. e.g., [START_REF] Biscione | The crisis of Central Asia urbanization in II millennium BC and villages as an alternative system[END_REF][START_REF] Vinogradova | Contacts Between the Steppe and Agricultural Tribes of Central Asia in the Bronze Age[END_REF][START_REF] Kohl | The making of Bronze Age Eurasia[END_REF][START_REF] Cattani | The Bronze Age and early Iron Age in the Margiana lowlands. Facts and methodological proposals for a redefinition of the research strategies, the archaeological map of the Murghab delta studies and Reports[END_REF]Salvatori 2008;[START_REF] Frachetti | Migration Concepts in Central Eurasien Archaeology[END_REF][START_REF] Frachetti | Multiregional emergence of mobile pastoralism and nonuniform institutional complexity across Eurasia[END_REF][START_REF] Cc | The Oxus Civilisation. La Civilización del Oxus[END_REF][START_REF] Luneau | La fin de la civilisation de l'Oxus. Transformations et recompositions des sociétés de l'âge du Bronze final en Asie centrale méridionale (1800-1500/1400 avant n.è[END_REF][START_REF] Luneau | Climate Change and the Rise and Fall of the Oxus Civilization in Southern Central Asia[END_REF][START_REF] Rouse | Mixing metaphors: sedentary-mobile interactions and local-global connections in prehistoric Turkmenistan[END_REF]. In this context analyses of isotopes such as strontium ( 87 Sr/ 86 Sr) and oxygen (δ 18 O) are today a common and powerful tool for a better understanding of interactions and exchange of past populations. This study takes a first step in exploring human mobility in southern Central Asia presenting isotopic analyses of a main corpus of samples from Ulug Depe in Turkmenistan and Dzharkutan in Uzbekistan, both sites belonging to the first urban centers in the region during the 3 rd and 2 nd mill. BCE. The results will be compared with single samples from other Bronze Age sites, such as Sapallitepa, Tilla Bulak and Bustan in southern Uzbekistan, Bashman 1 in central Uzbekistan, and Saridzhar and the nearby graveyards Gelot and Darnaichi in southern Tajikistan (fig. 1). The following discussion is based on the first analysis of human material from southern Central Asia. We are aware that the data at our disposal cannot yet produce statistically reliable results; however, since no isotopic studies on residential mobility have previously been conducted on populations in southern Central Asia, this study will provide a first biogeochemical data set of 87 Sr/ 86 Sr isotopes and an initial idea of the dynamics during the Bronze Age. 1 Biscione, Vahdati 2021, also called Oxus Civilization or Bactria-Margiana Archaeological Complex (BMAC) cf. e.g., [START_REF] Hiebert | Origins of the Bronze Age Oasis Civilization in Central Asia[END_REF][START_REF] Sarianidi | Gonurdepe. City of Kings and Gods[END_REF][START_REF] Francfort | L'âge du bronze en Asie centrale. La civilisation de l'Oxus[END_REF]; Lamberg-Karlovsky 2013; Teufer 2015; Salvatori 2016.

Context

Archaeological Background

Ulug Depe and Dzharkutan delivered the major part of the human material in this study. Ulug Depe is located in southern Turkmenistan in the northern submontane plains of the Kopet Dagh Mountains, 175 km south-east of the capital Ashgabat at 288 m a.s.l. (cf. e.g., Lecomte 2007a[START_REF] Lecomte | Ulug-depe: 4000 years of evolution between plain and desert. In: Historical and Cultural Sites of Turkmenistan[END_REF][START_REF] Lecomte | Activités archéologiques françaises au Turkménistan. In: Bendezu-Sarmiento J (ed) Archéologie française en Asie centrale[END_REF][START_REF] Bendezu-Sarmiento | Archéologie funéraire et bio-anthropologie à Ulug dépé et Dzharkutan. Âge du bronze au Turkménistan et en Ouzbékistan. In: Bendezu-Sarmiento J (ed) L'archéologie française en Asie centrale[END_REF][START_REF] Bendezu-Sarmiento | Some more exceptional discoveries at Ulug-depe[END_REF][START_REF] Luneau | Climate Change and the Rise and Fall of the Oxus Civilization in Southern Central Asia[END_REF]. In ancient times, Ulug Depe was situated adjacent to the Kelet River, which traverses the Kopet Dagh in the direction of Nishapur and presents a natural pass through the mountains [START_REF] Lecomte | Activités archéologiques françaises au Turkménistan. In: Bendezu-Sarmiento J (ed) Archéologie française en Asie centrale[END_REF]. Already in the Chalcolithic period, the first social changes towards a more centralized system are evidenced. The construction of a fortification wall, as well as the separation of craft areas and the beginning of irrigated agriculture, reflects the changing nature of property and territorial management, as well as a certain social differentiation [START_REF] Lecomte | Ulug-depe: 4000 years of evolution between plain and desert. In: Historical and Cultural Sites of Turkmenistan[END_REF]. With the appearance of the GKC, Ulug Depe had a period of particular prosperity. Impressive public monuments, such as the remains of high terraces were discovered [START_REF] Lecomte | Ulug-depe: 4000 years of evolution between plain and desert. In: Historical and Cultural Sites of Turkmenistan[END_REF][START_REF] Bendezu-Sarmiento | Habitat and Occupancy during the Bronze Age in Central Asia. Recent work at the sites of Ulug-depe (Turkmenistan) and Dzharkutan (Uzbekistan), Urban Cultures of Central Asia from the Bronze Age to the Karakhanids[END_REF]. Numerous finds of gold, lapis lazuli, carnelian and alabaster reflect widespread connections to the Indus Valley and the Iranian Plateau (Bendezu-Sarmiento, Lhuillier 2016: 527 figs. 4-6).

The situation in Dzharkutan is different: at the end of the 3 rd mill. BCE the Sapalli culture, a local variant of the GKC, arose in northern Bactria and several new settlements such as Dzharkutan, Sapallitepa, Bustan, Molali, and Tilla Bulak developed in the Surkhan Darya Valley (fig. 1) [START_REF] Askarov | Džarkutan[END_REF][START_REF] Shirinov | Die frühurbane Kultur der Bronzezeit im südlichen Mittelasien. Die vorgeschichtliche Siedlung von Dzharkutan[END_REF][START_REF] Huff | Uzbek-German archaeological researches in the Surkhan Darya region[END_REF][START_REF] Huff | Dzharkutan, Uzbekistan[END_REF]Bendezu-Sarmiento, Mustafakulov 2013;[START_REF] Kaniuth | Life in the countryside. The rural archaeology of the Sapalli culture[END_REF]. The establishment of these new settlements has been associated with an increased mobility of the populations (e.g., [START_REF] Frachetti | Migration Concepts in Central Eurasien Archaeology[END_REF][START_REF] Frachetti | Multiregional emergence of mobile pastoralism and nonuniform institutional complexity across Eurasia[END_REF]Bendezu-Sarmiento, Mustafakulov 2013). The Surkhan Darya Valley is located in southern Uzbekistan, ca. 50 km north of the district capital Termez, at an altitude around 350 m a.s.l. Dzharkutan with a size of about 40-50 ha is the biggest site in the Shurkan Darya Valley, including several mounds with traces of occupation, a citadel with a palace, a temple and large necropolises [START_REF] Shirinov | Die frühurbane Kultur der Bronzezeit im südlichen Mittelasien. Die vorgeschichtliche Siedlung von Dzharkutan[END_REF][START_REF] Huff | Dzharkutan, Uzbekistan[END_REF]Bendezu-Sarmiento, Mustafakulov 2013). Artifacts, mainly pottery influenced by the Andronovo Culture from the steppes were discovered in Dzharkutan, reflecting dynamic interactions with the related farmer-breeder culture from the Pamir foothills of southwestern Tajikistan, the so called Vakhsh culture [START_REF] Luneau | Вахшская культура на Джаркутане (Узбекистан, бронзовый век): Новое освоение ? [The Vakhsh culture at Dzharkutan (Uzbekistan, Bronze Age): a new occupancy?[END_REF][START_REF] Luneau | Transfers and Interactions between North and South in Central Asia during the Bronze Age[END_REF].

There is considerable uncertainty regarding the regional cohesion and territorial hegemony of the GKC. In particular throughout south/western Tajikistan, researchers have documented numerous instances of mixed cultural remains that include next to GKC-type materials also materials described as "local" (Vakhsh) as well as related to the "steppe" (Andronovo, Federovo) (e.g., [START_REF] Rouse | Silent partners: archaeological insights on mobility, interaction and civilization in Central Asia's past[END_REF], Teufer 2021[START_REF] Vinogradova | The formation of the Oxus Civilization/BMAC in southwestern Tajikistan[END_REF]. Our sampling thus includes several other sites in addition to the GKC-related centres of Ulug Depe and Dzharkutan. The nearby site of Sapallitepa and the cemetery of Bustan help round out the picture of GKC-related sites in southern Uzbekistan, while the cemeteries of Gelot/Darnachi and the Saridzhar settlement in Tajikistan represent a complex intersection with communities in the upper Yakh-Su River Valley [START_REF] Teufer | Der Baktro-Margianische Archäologische Komplex und die Oxus-Zivilisation[END_REF][START_REF] Teufer | Der Übergang von der Spätbronze-zur Früheisenzeit in Mittelasien[END_REF]. Likewise, the samples from Bashman 1 in central Uzbekistan will help establish baselines of communication between the GKC and Andronovo related communities (e.g., Luneau 2017).

Chronological and anthropological context

The human material analysed in this study was collected by different archaeological expeditions during the last decades and often the local possibilities as well as availability and preservation of the material limited the selection. Hence, it was not possible to present a representative sample of all sexes and age groups. Nevertheless, the remains of 32 human individuals from eight sites in southern Central Asia were used for the present study: eleven individuals from Ulug Depe, eleven from Dzharkutan, two from Sapallitepa, one from Bustan, two from Gelot/Darnaichi, three from Saridzhar and two from Bashman 1 (cf. tab. 1 and 4). In Ulug Depe four burials (2 men, 1 undetermined adult, 1 child) date to the Early Bronze Age (EBA, Namazga IV (NMG IV), ca. 2800-2500 BCE), two burials (1 woman, 1 child) date to the transition from the Early to the Middle Bronze Age (EBA-MBA, NMG IV-V) and five burials

(1 man, 1 woman, 2 undetermined adults, 1 child) to the later phase of the Middle Bronze Age (MBA (NMG V), ca. 2200-1900BCE, cf. also Bendezu-Sarmiento 2013). The Ulug group consisted of three men, two women, three undetermined adults and three children.

The eleven individuals from Dzharkutan date between 2100 and 1700 BCE, corresponding to the transition from the MBA to the LBA and the LBA (NMG V-VI, NMG VI; cf. also Bendezu-Sarmiento, Mustafakulov 2013). A young woman and one undetermined adult dated back to the end of the 3rd/beginning of the 2nd mill. BC (MBA/LBA), nine individuals (1 man, 4 women, 3 undetermined adults, 1 child) dated back to the LBA, ca. 1900 and 1700 BC. In a total the group consists of five women, one man, four undetermined adults and one child.

The two individuals from nearby Sapallitepa coincides with the earliest phase of the LBA [START_REF] Askarov | Sapallitepa[END_REF]. Sapallitepa is located about 40 km southwest of Dzharkutan, close to the northern bank of the Amu Darya River. The hills of Bustan are located 5 km south of Dzharkutan and dates to the final phase of the Bronze Age [START_REF] Avanesova | Bustan VI -The necropolis of fire-worshippers of pre-urban Bactria[END_REF]. The graveyards of Gelot/Darnaichi and the neighboured settlement Saridzhar are located on the banks of the Yakh-Su River in southern Tajikistan [START_REF] Teufer | Das Gräberfeld von Gelot[END_REF][START_REF] Teufer | Spätbronzezeitliche Grabfunde aus Nordbaktrien und benachbarten Regionen. Studien zur Chronologie zwischen Aralsee und Persischem Golf. AIT 13. Teufer M[END_REF][START_REF] Lombardo | Excavations of the burial ground of Gelot in 2007-2010[END_REF][START_REF] Vinogradova | Погребальные памятники эпохи бронзы в Южном Таджикистане (могильники Гелота и Дарнайчи) / Институт востоковедения (Burial Sites of the Bronze Age in Southern Tajikistan -Gelot and Darnay Chi necropolises-)[END_REF]. The two burials from Gelot/Darnaichi belong to the so called Pjandzh culture and date between 2450 and 1900 cal. BCE [START_REF] Teufer | Der Baktro-Margianische Archäologische Komplex und die Oxus-Zivilisation[END_REF][START_REF] Teufer | Der Übergang von der Spätbronze-zur Früheisenzeit in Mittelasien[END_REF] The choice of human material was made mainly on the basis of the in-situ conservation of the burials after excavation, since a large part of the burials were looted in the past. Teeth were removed as a priority according to their maxillo-mandibular state of preservation. inter-individual comparisons difficult as the teeth evolve in different stages of life (cf. Knipper 2004: 602 fig. 6;[START_REF] Hillson | Teeth[END_REF]. In this study mainly molars (M3) were analysed, which represent a later stage of child-and teenager years. The human bone material consisted mainly of ribs, vertebras and phalanges. Their remodelling rate depends on the particular bone and can vary between 5 and 30 years (cf. Tütken 2010: 35 fig. 2). Long-bones as femurs, tibias and cranium have slow remodelling rates of 20 to 30 years, whereas ribs and pelvic bones have faster turnover rates of 5 to 10 years (cf. e.g., Knipper 2004: 610-615;Tütken 2010: 35). The detailed description of the methods used for the anthropological determination of gender and age can be found in Bendezu-Sarmiento 2013.

Table 1: Simplified comparative chronology of the sites according to the analysed human remains

Ecological and geo-chemical realities

One of the main issues of the present study was the description of the distribution of 87 Sr/ 86 Sr isotopes in southern Central Asia. The general concept of mobility studies is based on the comparison of the biogenic signature of an individual with the so called isolandscape (cf. [START_REF] Evans | Spatial variations in biosphere 87Sr/86Sr in Britain[END_REF][START_REF] Bowen | The Online Isotopes in Precipitation Calculator[END_REF][START_REF] Maurer | Bioavailable 87 Sr/ 86 Sr in different environmental samples -Effects of anthropogenic contamination and implications for isoscapes in past migration studies[END_REF]. Isolandscapes record the spatial distribution of the local isotopic composition of environmentally bioavailable 87 Sr/ 86 Sr.

All the sites analysed here are located along the northern foothills of Kopet Dagh Mountains, the eastern foothills of Kugitang Mountains and the southern foothills of the Khodzhasartes Mountains (fig. 2). The Kopet Dagh submontane region is formed from alluvial fan deposits and younger Quaternary loess deposits [START_REF] Fet | Biogeography and Ecology of Turkmenistan[END_REF][START_REF] Atamuradov | Biodiversity, genetic diversity, and projected areas in Turkmenistan[END_REF]. The Surkhan Darya Valley is covered by layers of clayish and sandy loess, underneath a thick layer of continental deposits mainly consists of sedimentary rocks (sandstone and aleurolite) with sporadic volcanic outcrops [START_REF] Mukin | Encyclopedia of European and Asian regional Geology[END_REF][START_REF] Kaniuth | Life in the countryside. The rural archaeology of the Sapalli culture[END_REF] Amu Darya Basin provided 87 Sr/ 86 Sr ratios between 0.7078 and 0.7084 [START_REF] Meisel | Combined osmium and strontium isotopic study of the Cretaceous-Tertiary boundary at Sumbar, Turkmenistan: A test for an impact vs. a volcanic hypothesis[END_REF]Zheng et al. 2011), while Caspian Sea deposits resulted in 87 Sr/ 86 Sr ranges around 0.7081 [START_REF] Clauer | Fluctuations of Caspian Sea level: Beyond climatic variations?[END_REF]. [START_REF] Fet | Biogeography and Ecology of Turkmenistan[END_REF][START_REF] Miller | Agricultural development in western Central Asia in the Chalcolithic and Bronze Ages[END_REF][START_REF] Moore | Agriculture and herding in early oasis settlements of the Oxus civilization[END_REF][START_REF] Miller | Agricultural development in western Central Asia in the Chalcolithic and Bronze Ages[END_REF][START_REF] Miller | The use of plants at Anau North[END_REF][START_REF] Tengberg | Économies végétales et environnements en Asie centrale du Néolithique à l'époque sassanide : la contribution des disciplines archéobotaniques. In: Bendezu-Sarmiento J (ed) L'archéologie française en Asie centrale[END_REF]

Material and Methods

Isotopic applications and their problems

Isotope analysis is a reliable method for tracking human and animal origins and mobility at a lifetime scale (cf. e.g., [START_REF] Price | Characterization of biologically available strontium isotope ratios for the study of prehistoric migration[END_REF][START_REF] Price | Strontium isotopes and prehistoric human migration: the Bell Beaker period in central Europe[END_REF][START_REF] Tütken | Die Bedeutung der Knochenfrühdiagenese für die Erhaltungsfähigkeit in vivo erworbener Element-und Isotopenzusammensetzungen in fossilen Knochen[END_REF][START_REF] Knipper | Die Strontiumisotopenanalyse: eine naturwissenschaftliche Methode zur Erfassung von Mobilität in der Ur-und Frühgeschichte[END_REF][START_REF] Miller | Isotopic investigations of pastoralism in prehistory[END_REF].

The ratio of strontium 87 Sr/ 86 Sr depends on water sources and the geological formation with which the water has interacted. Strontium is dissolved out of rocks by the groundwater, permeating through rivers and other water sources into soils and plants. It enters the body through drinking and eating and is incorporated without substantial fractionation into the hydroxyapatite of hard tissues like bones and teeth, often referred to as biogenic strontium (e.g., [START_REF] Tütken | Die Bedeutung der Knochenfrühdiagenese für die Erhaltungsfähigkeit in vivo erworbener Element-und Isotopenzusammensetzungen in fossilen Knochen[END_REF][START_REF] Bentley | Strontium isotopes from the earth to the archaeological skeleton: a review[END_REF]). The water and food ingested by an organism is thus directly connected to the nature of the geological substrates [START_REF] Faure | Principles of Isotope Geology[END_REF][START_REF] Faure | Isotopes: Principles and Applications[END_REF]. Moreover, tooth enamel is synthesized during childhood and remains static. Therefore, the isotopic ratio of tooth enamel reflects the environment in which the organism evolved during the first years of its life. Bones undergo continuous modification during the whole life and isotopes reflect the situation of the last years before death. Differences between bones and teeth, therefore, provide evidence for changes and the mobility of humans and animals during their lifetime [START_REF] Price | Characterization of biologically available strontium isotope ratios for the study of prehistoric migration[END_REF][START_REF] Bentley | Strontium isotopes from the earth to the archaeological skeleton: a review[END_REF][START_REF] Burton | Seeking the local 87Sr/86Sr ratio to determine geographic origins of humans[END_REF].

The ratio of oxygen 18 O/ 16 O (δ 18 O) in mammals reflects the sources of incorporated water, such as drinking water and the water in edible plants (e.g., [START_REF] Balasse | The seasonal mobility model for prehistoric herders in the south-western cape of South Africa assessed by isotopic analysis of sheep tooth enamel[END_REF][START_REF] Balasse | A key to the adaptation of Neolithic husbandry in the Orkneys: contribution of seaweed to the sheep diet at the Holm of Papa Westray, revealed through stable isotope analysis (δ13C and δ18O) of teeth[END_REF]. The values reflect the composition of local meteoric water, derived from precipitation as rain, snow, or atmospheric moisture. The oxygen composition varies with different factors such as humidity, temperature, rain shadow effects, altitude, latitude and distance from the sea [START_REF] Longinelli | Oxygen isotopes in mammal bone phosphate: a new tool for palaeohydrological and palaeoclimatological research[END_REF][START_REF] White | Oxygen isotopes and the 33 identification of geographical origins: The Valley of Oaxaca versus the Valley of Teotihuacan[END_REF][START_REF] White | Exploring the Effects of Environment, Physiology and Diet on Oxygen Isotope Ratios in Ancient Nubian Bones and Teeth[END_REF].

It can be evidence of local water sources and climate conditions in which an individual grew up and is, therefore, another indicator for the origins and movements of humans and animals [START_REF] Budd | Investigating population movement by stable isotope analysis: A Report from Britain[END_REF][START_REF] Millard | Direct evaluation of archaeological immigration, population dynamics and lead exposure by isotope biogeochemistry[END_REF][START_REF] White | Exploring the Effects of Environment, Physiology and Diet on Oxygen Isotope Ratios in Ancient Nubian Bones and Teeth[END_REF]Bentley, Knipper 2005). The oxygen signal of an individual is not only impacted by the surrounding habitat but also by several physiological factors, such as individual metabolism and water intake, body temperature, or heat loss mechanisms [START_REF] Makarewicz | Oxygen (δ18O) and carbon (δ13C) isotopic distinction in sequentially sampled tooth enamel of co-localized wild and domesticated caprines: Complications to establishing seasonality and mobility in herbivores[END_REF], Ventresca Miller 2018). Moreover, culturally related manners as the intake of brewed, fermented, or cooked beverages can affect the δ 18 O ratios [START_REF] Brettell | Brewing and stewing: The effect of culturally mediated behaviour on the oxygen isotope composition of ingested fluids and the implications for human provenance studies[END_REF][START_REF] Royer | Carbon, nitrogen and oxygen isotope fractionation during food cooking: Implications for the interpretation of the fossil human record[END_REF], as well as weaning can have an impact on the δ 18 O ratio in body tissues [START_REF] White | Exploring the Effects of Environment, Physiology and Diet on Oxygen Isotope Ratios in Ancient Nubian Bones and Teeth[END_REF]). Additionally, seasonal variations have to be taken into account. The mineralization of body tissues generally covers a period of several years and might be impacted by seasonal changes through time. Central Asia is dominated by a dry, hot and arid vegetation, groundwater sources like springs, wells, rivers, or lakes may have been seasonal and differ over time. Furthermore, many regions in the world as e.g., tropical zones have similar δ 18 O values, ranging from approximately -2.0 to -8.0 (VSMOW), so that a distinction of these regions is difficult [START_REF] Bowen | Global application of stable hydrogen and oxygen isotopes to wildlife forensics[END_REF][START_REF] Sjögren | A complex Neolithic economy: isotope evidence for the circulation of cattle and sheep in the TRB of western Sweden[END_REF]. Therefore, δ 18 O results will be taken only for the interpretation of inter-individual variations.

Diagenesis can have a critical impact on the isotopic composition of human remains. Bones, but especially tooth dentine are very sensible to diagenesis -the ability of isotopes to penetrate from the surrounding milieu into the material. Decay processes as well as bone density, temperature and humidity/aridity can strongly modify the original isotopic composition (e.g., [START_REF] Behrensmeyer | Taphonomic and ecologic information from bone weathering[END_REF][START_REF] Budd | Differential diagenesis of strontium in archaeological human dental tissues[END_REF][START_REF] Denys | Taphonomy and experimentation[END_REF][START_REF] Hedges | Bone Diagenesis: An Overview of Processes[END_REF]Hoppe et al. 2003;[START_REF] Tütken | Die Bedeutung der Knochenfrühdiagenese für die Erhaltungsfähigkeit in vivo erworbener Element-und Isotopenzusammensetzungen in fossilen Knochen[END_REF][START_REF] Tütken | Die Isotopenanalyse fossiler Skelettreste -Bestimmung der Herkunft und Mobilität von Menschen und Tieren. Tagungsband des 2. Mitteldeutschen Archäologentages in Halle (Saale): Anthropologie, Isotopie und DNA -biographische Annäherung an namenlose vorgeschichtliche Skelette? Tagungen des Landesmuseums für Vorgeschichte Halle[END_REF][START_REF] Maurer | Bioavailable 87 Sr/ 86 Sr in different environmental samples -Effects of anthropogenic contamination and implications for isoscapes in past migration studies[END_REF].

Depending on the conservation of the material, diagenetic effects, especially of recent, well-preserved material, can be more or less completely eliminated by careful mechanical ablation of the topmost layers of the bone compacta followed by a specific leaching treatment with NaOCl and NaOH or acetic acid solutions (Hedges 2002: 322;Hoppe et al. 2003: 25-26;Tütken 2003: 217). Carbonized plant remains also strongly undergo diagenetic changes. Although exogenous strontium does not replace all biogenic strontium and is removable through leaching with strong acid [START_REF] Fiorentino | Stable isotopes in archaeobotanical research[END_REF][START_REF] Styring | Revisiting the Potential of carbonized grain to preserve biogenic 87Sr/86Sr signatures within the burial environment[END_REF], potential diagenetic alterations always have to be taken into account when interpreting isotopic data. The strong homogeneity of 87 Sr/ 86 Sr results of Ulug Depe bones attracts attention, as all of them fall within a very narrow strontium range. It may be feared that these results are caused by contamination through diagenetic processes. Although the assessment of the diagenetic effect on the 87 Sr/ 86 Sr ratios through measuring the concentration of the elements was not performed on the samples, Ulug Depe bones were in very good conditions and leaching with strong acid should have removed the diagenetic impact for isotopic measurements. Moreover, both chemical extractions and measurements were conducted in multiple sessions over a period of two years with each session incorporating samples of different material, species and origins. Therefore, systematic mistakes within the analytical process can be excluded and the results will be considered as reliable.

Reference material

For the determination of the 2013, et al. 2020). Rodents, such as mice, have a natural lifespan of around 2-3 years and form territorial family clans. Hence, their bone compositions can be considered as representative of the surrounding environment and deliver reliable information about the bioavailable strontium (e.g., [START_REF] Knipper | Die Strontiumisotopenanalyse: eine naturwissenschaftliche Methode zur Erfassung von Mobilität in der Ur-und Frühgeschichte[END_REF]Bentley et al. 2004). When only human material was available as it was the case in Bashman 1, tooth dentine was analysed. Primary dentine is particularly susceptible to diagenetic alterations and represents the bioavailable strontium of the environment rather than the biogenic signal of the individual (cf. e.g., [START_REF] Gerling | Prehistoric Mobility and Diet in the West Eurasian Steppes 3500 to 300 BC: An Isotopic Approach[END_REF]. Plants were used in form of carbonized grains and charred wood from Bronze and Iron Age layers [START_REF] Tengberg | Économies végétales et environnements en Asie centrale du Néolithique à l'époque sassanide : la contribution des disciplines archéobotaniques. In: Bendezu-Sarmiento J (ed) L'archéologie française en Asie centrale[END_REF][START_REF] Tengberg | Environment and Subsistence Economies at Iron Age Ulug-depe, South-eastern Turkmenistan: First Results from the Archaeozoological and Archaeobotanical Studies[END_REF]. In general, all reference samples were collected during the excavations, and we avoided using modern material because of possible complications with the influence of fertilizers or imported animal feed [START_REF] Böhlke | Strontium isotope geochemistry of groundwaters and streams affected by agriculture[END_REF]Bentley, Knipper 2005;[START_REF] Maurer | Bioavailable 87 Sr/ 86 Sr in different environmental samples -Effects of anthropogenic contamination and implications for isoscapes in past migration studies[END_REF].

Applied laboratory methods

Analyses were conducted on bone compacta, tooth enamel and primary tooth dentine. All steps were performed in a sterile atmosphere, tools were cleaned with ethanol and in the ultrasonic bath. Bones were cleaned of dirt with a toothbrush and a diamond drill. The sampling was proceeded with a micro saw followed by careful crushing with an agate mortar and pestle. Teeth were cleaned with a toothbrush and a diamond drill, enamel and dentine sampling was undertaken with a diamond drill.

Charred plants were mechanically cleaned of sand and dust with a needle and tweezers under the microscope. After crushing and the treatment with 6 M HCl for 24 hours after [START_REF] Styring | Revisiting the Potential of carbonized grain to preserve biogenic 87Sr/86Sr signatures within the burial environment[END_REF], the samples were transformed into ash in a ceramic beaker at 750°C for 12 hours. The residues were solved in 1 ml 13 M HNO3 in the Ultrasonic bath followed by the evaporation of the acid solution on a hot plate (100⁰C) overnight.

The extraction of strontium was performed with 10-15 mg tooth enamel and 20-25 mg bone compacta/tooth dentine. The leaching procedure to remove the diagenetic strontium was undertaken with 7% acetic acid in an ultrasonic bath (45°C) for 30 minutes followed by several rinsing steps with ultrapure H2O Milli-Q®, changing the solution every 10 minutes until it became clear (only enamel and bones were leached, dentine was only rinsed in water). The samples were dried overnight. The cleaned, leached and oven dried samples were transferred to a clean Teflon beaker and dissolved in 1 ml 13 M HNO3 in the Ultrasonic bath at 65°C. Acid was evaporated on a hot plate at 100°C and samples were dissolved in 2 ml 2 M HNO3. Strontium was extracted through a Teflon column using "Sr-Eichrom" resin [START_REF] Pin | Concomitant separation of strontium and samariumneodymium for isotopic analysis in silicate samples, based on specific extraction chromatography[END_REF]) after the following protocol: columns were washed 6 times alternately with 5 ml 6 M HCl and 0.05 M HNO3 followed by the conditioning step with 3 ml 2 M HNO3. After uploading the samples, the elimination of other elements was performed with 2 ml 2 M HNO3, 3 ml 7 M HNO3 and

Results

Determination of the local 87 Sr/ 86 Sr ranges

Several methods exist for the calculation of local 87 Sr/ 86 Sr signals to get the most reliable results (e.g., [START_REF] Grupe | Mobility of the Bell Beaker people revealed by strontium isotope ratios of tooth and bone: a study of southern Bavarian skeletal remains[END_REF][START_REF] Price | Characterization of biologically available strontium isotope ratios for the study of prehistoric migration[END_REF][START_REF] Price | Strontium isotopes and prehistoric human migration: the Bell Beaker period in central Europe[END_REF]Bentley et al. 2004;[START_REF] Knipper | Die Strontiumisotopenanalyse: eine naturwissenschaftliche Methode zur Erfassung von Mobilität in der Ur-und Frühgeschichte[END_REF]). In order to compare our results with already published data, we followed [START_REF] Price | Characterization of biologically available strontium isotope ratios for the study of prehistoric migration[END_REF] The bio-available local 87 Sr/ 86 Sr range of Ulug Depe was determined using three samples of rodents and two of carnivores [START_REF] Mashkour | Sociétés pastorales et économies de subsistance au Nord Est de l'Iran et au Sud du Turkménistan. In: Bendezu-Sarmiento J (ed) L'archéologie française en Asie centrale[END_REF], supplemented by four samples of barley, supposed to be grown locally, one sample of juniper wood, a mountainous species, and one sample of tamarisk, with a high variety of adaptation, but in this region mainly growing along rivers and in the plain [START_REF] Tengberg | Environment and Subsistence Economies at Iron Age Ulug-depe, South-eastern Turkmenistan: First Results from the Archaeozoological and Archaeobotanical Studies[END_REF]. The ratios ranged between 0.707885 and 0.708045 with an average of 0.707964 To get a better idea of the surrounding situations, further faunal samples were added from Tilla Bulak, a small village 25 km west of Dzharkutan, dating around 2000-1750 BCE [START_REF] Kaniuth | The Late Bronze Age Settlement of Tilla Bulak (Uzbekistan) -a summary of four years´ work[END_REF].

(± 0.000045),
Seven samples of barley and wheat were analysed (Peters in Kaniuth 2009, 89-91): the ratios ranged between 0.708930 and 0.708968 with an average of 0.708948 (± 0.000015), resulting in a narrow, but significantly different local 87 Sr/ 86 Sr range of 0.708918 -0.708978 (±2σ, n = 7).

The two human individuals from Bashman 1 were tested for their dentine 87 Sr/ 86 Sr ratios. The results were close to each other (0.709297 and 0.709343), giving an impression of the strontium distribution in this region. The enamel ratio of the child was also close to the two dentine ratios; as it was a young child (below 7 years) and the analysed tooth a molar (formation not finished within this age), the child was added to the calculation to get the widest possible description of local strontium distribution. Then, the ratios ranged between 0.709297 and 0.709445 with an average of 0.709362 (± 0.000062), resulting in a local 87 Sr/ 86 Sr signal of 0.709238 -0.709485 (±2σ, n = 3).

Several analyses of rodents were included as further references: these do not provide reliable local 87 Sr/ 86 Sr signals, but serve as indicators for the isotopic distribution of the archaeological sites.

Hence, the bone material of one rodent from Sangir-tepe, of one from Erkurgan (Mashkour et al. 2016) and of two from Geoktchik Depe [START_REF] Mashkour | The subsistence Economy in the Rural Community of Geoktchik Depe in Southern Turkmenistan; Preliminary Results of the Faunal Analysis[END_REF] were analysed. Geoktchik Depe is located in the Dehistan Plain, in southwestern Turkmenistan, adjacent to the Caspian Sea, which is today an arid and flat region [START_REF] Lecomte | The Iron Age of Northern Hyrcania[END_REF](Lecomte , 2007b)). The two rodents from Geoktchik Depe showed completely different 87 Sr/ 86 Sr ratios, resulting in a wide range of 0.708102 -0.709616 (±2σ, n = 2). The rodent from Sangirtepe displayed a similar 87 Sr/ 86 Sr ratio of 0.709224 (± 0.000006), while that from Erkurgan a ratio of 0.708273 (± 0.000003) closer to those from Ulug Depe and Dzharkutan. The calculated local signals of the single sites were resultful within the available references and are well distinguishable at a micro-regional scale (cf. fig. 3). The calculated strontium signal of the whole region was calculated resulting in a range of 0.707466 -0.709469 (±2σ, n = 34).

Interpolation on an interregional scale

The geographic regions of southern Central Asia comprise a large area with very diverse geological conditions, making interregional comparisons difficult. But the obtained local signals are sufficiently distinctive for a first evaluation on an interregional scale. The background strontium isotope values for the region were reconstructed by interpolating the data for the geological units using the kriging method. The strontium isotope values of the geological units with references can be found in the supplementary. Although the accuracy of this reconstruction is limited by the available data and their locations, higher 87 Sr/ 86 Sr ratios (~0.70800-0.70850) are seen to the north of Dzharkutan while lower values (~0.70605-0.70700) were observed near Ulug Depe (fig. 4).

Human 87 Sr/ 86 Sr and δ 18 O results

The 87 Sr/ 86 Sr and δ 18 O results of all human samples from Ulug Depe, Dzharkutan, Sapallitepa, Bustan, Bashman 1, Gelot/Darnaichi and Saridzhar are listed in table 3 and presented in figures 5, 6 and 7 (the individuals from Bashman 1 were only tested for strontium, and are therefore not in figs. 6 and 7). A preliminary cluster analysis of Ulug Depe and Dzharkutan individuals provided two distinguishable clusters with several outliers. Hence the sites can be considered as capable of being differentiated. A Levene test confirmed that there was no homogeneity of variances between the sites (F = 2.16, p < 0.02). But since the small sample number made statistical analyses unreliable, we desisted from further calculations. Moreover, the deviations of the individual results were negligibly small, when plotting them on the figures the error bars were overlapped by the applied symbols so that the symbols in figures 5, 6 and 7 encompass the error margins at 2σ level for the 87 Sr/ 86 Sr ratios and 1σ level for δ 18 O ratios. The 87 Sr/ 86 Sr ratios of all samples from Ulug Depe ranged between 0.707864 and 0.709960, δ 18 O ratios were between -6.9‰ and -2.4‰ (VPDB). Bone 87 Sr/ 86 Sr ratios ranged between 0.707864 and 0.707948 with a mean of 0.707893 (± 0.000026, n = 11), δ 18 O bone ratios ranged between -5.3‰

and -2.4‰ and showed a mean of -3.7‰ (± 0.97, n = 11). Tooth enamel 87 Sr/ 86 Sr ranged between 0.707819 and 0.709960 and showed a mean of 0.708156 (± 0.000605, n = 11), while δ 18 O ranged between -6.9‰ and -3.2‰ with a mean of -4.4‰ (± 1.08, n = 11). The 87 Sr/ 86 Sr ratios of all samples from Dzharkutan ranged between 0.708052 and 0.709200, δ 18 O ratios of all samples ranged from -6.9‰ to -3.8‰ (V-PDB). The 87 Sr/ 86 Sr ratio of human bones ranged between 0.708160 and 0.708474 and showed a mean of 0.708352 (± 0.000081, n = 9), bones δ 18 O ranged between -6.5‰ and -4.8‰

and showed a mean of -5.6‰ (± 0.52, n = 9). Tooth enamel 87 Sr/ 86 Sr ratios ranged between 0.708052 and 0.709200 and showed a mean of 0.708267 (± 0.000316, n = 11), while enamel δ 18 O ranged between -6.9‰ and -5.0‰ with a mean of -6.2‰ (± 0.49, n = 11). The bone sample of burial 20 from Sapallitepa provided an 87 Sr/ 86 Sr ratio of 0.708418 (± 0.000006), while enamel 87 Sr/ 86 Sr ratio of burial 8 was 0.709030 (± 0.000026). The single bone sample from Bustan had an 87 Sr/ 86 Sr ratio of 0.707893 (± 0.000007), δ 18 O was -5.7‰. The five individuals from Gelot/Darnaichi and Saridzhar range in the 87 Sr/ 86 Sr ratio between 0.708616 and 0.709374 (± 0.000241‰), δ 18 O ratios ranged between -2.8‰ and -7.8‰ (± 1.4‰). The two individuals from Bashman 1 showed in their 87 Sr/ 86 Sr enamel ratios two very different results. The 87 Sr/ 86 Sr enamel ratio of the adults was 0.710410 (± 0.000040), the child provided an 87 Sr/ 86 Sr enamel ratio of 0.709445 (± 0.000007). The preparation of structural carbonate was not sufficient for all individuals; therefore, oxygen values are not available for one sample from Sapallitepa and all samples from Bashman 1.

Discussion

The 87 Sr/ 86 Sr and δ 18 O results from Ulug Depe suggest that all the analysed individuals lived their last years in Ulug Depe or the surrounding area (figs. [START_REF] Longinelli | Oxygen isotopes in mammal bone phosphate: a new tool for palaeohydrological and palaeoclimatological research[END_REF][START_REF] White | Exploring the Effects of Environment, Physiology and Diet on Oxygen Isotope Ratios in Ancient Nubian Bones and Teeth[END_REF]). Especially, the small inter-individual variations of the bone samples indicate that people ingested water from particular water sources and not from multiple sources spread across the landscape (single site between 0.5 and 3‰ after [START_REF] White | Exploring the Effects of Environment, Physiology and Diet on Oxygen Isotope Ratios in Ancient Nubian Bones and Teeth[END_REF]Lightfoot, O´Connell 2016). The higher tooth enamel range evidences that the water sources of people's origin/childhood varied a bit more (fig. 6). 1 is noticeable, as it fell together with ULG 56 outside the calculated regional signal, suggesting an external origin of this individual too (fig. 5). Bashman 1 is located south of the Syr Darya which marks the northern border of the GKC and an area inhabited by both-the GKC groups and Andronovo groups -in the first half of the 2 nd mill. BCE. Isotopic studies from the northern communities, where nomadic pastoralism is argued to be a reason for the spread of the Andronovo culture, did not provide evidence for long distance migration [START_REF] Miller | Pastoralist Mobility in Bronze Age Landscapes of Northern Kazakhstan: 87Sr/86Sr and δ18O Analyses of Human Dentition from Bestamak and Lisakovsk[END_REF]. Although providing a contrasting image, our results are provisional but, nevertheless the high variation in the results suggests active mobility among the inhabitants of southern Central Asia during the Bronze Ages.

Conclusion

The present study has provided a first biogeochemical dataset of 87 Sr/ 86 Sr isotopes from southern

Central Asia and has enabled the initial evaluation of the isotopic distribution on a micro-regional scale.

The analyses of 87 Sr/ 86 Sr and δ 18 O isotopes on human material indicate that the populations in Ulug

Fig. 1

 1 Fig. 1 Topographic map of the studied region with the investigated sites including symbols of the analysed material after https://maps-for-free.com/

Fig. 2 :

 2 Fig. 2: Geological maps of southern Central Asia after Ghassemi et al. 2019: 127 fig. 2 (Turkmenistan) and Sanchez de Corral, Thum 2012: 92 fig. 3 (Uzbekistan, Tajikistan)

0. 5

 5 ml 3 M HNO3. The extraction of strontium was accomplished with 4 ml 0.05 M HNO3. The lab work of the strontium extraction was carried out in the clean isotope laboratory of the Geoscience Montpellier (CNRS -University of Montpellier). The measurements were realized using a Thermo Scientific MC-ICP-MS (MultiCollector-Inductively Coupled Plasma Mass Spectrometer) Neptune Plus at the AETE-ISO Platform from the OSU-OREME (Montpellier). To assess the reproducibility and accuracy of the isotopic ratios, standards were repeatedly run every five samples. All ratios were normalized using a value of 0.1194 for the88 Sr/ 86 Sr ratio. The standard average values were 0.710243 ± 6 (±2σ, n = 20) for the NBS987 Sr standard.For the preparation of structural carbonate for the oxygen analyses, because of the state of preservation varying amounts of mechanically cleaned bone compacta were required: Ulug bones 10-15 mg; Dzharkutan, Gelot/Darnaichi, Saridzhar, and Bashman1 bones 20-30 mg. The required amount of tooth enamel was 5-10 mg. The purification was performed following the protocol of[START_REF] Balasse | The seasonal mobility model for prehistoric herders in the south-western cape of South Africa assessed by isotopic analysis of sheep tooth enamel[END_REF]. To remove the diagenetic carbonate, bone samples were treated with NaOCl (2-3%) for 24-48 hours at room temperature, stirred every 4-6 hours. After rinsing (4-5 times with H2O Milli-Q®), 1 M acetic acid was added to the bone powder for 1 hour at room temperature, stirred every 20 minutes.Teeth enamel samples were treated with 1 M HCl for 4 hours, stirred every 30 minutes. After rinsing (4-5 times with H2O Milli-Q®), all samples were dried at 50-70°C for 24-36 hours until all water was thoroughly evaporated. The lab work was carried out in the Cosmochemistry Lab of the Mass Spectrometry Service at the National Museum of Natural History (SSMIM) in Paris. The analyses were performed using a Thermo Scientific Mass-spectrometer DeltaV-Advantage with a Kiel IV automated processor. Oxygen ratios are reported compared to the Vienna Pee Dee Belemnite standard (VPDB) using δ notation. Uncertainties (1σ) for δ 18 O were 0.06‰, the measurements are expressed relative to the standard in parts per thousand (‰).

  resulting in a local 87 Sr/ 86 Sr range for Ulug Depe of 0.707874 -0.708054 (±2σ, n = 11).For the bio-available local 87 Sr/ 86 Sr range of Dzharkutan, two samples of rodents, five botanical samples and two human dentine samples were analysed(Mashkour et al. 2016;[START_REF] Tengberg | Économies végétales et environnements en Asie centrale du Néolithique à l'époque sassanide : la contribution des disciplines archéobotaniques. In: Bendezu-Sarmiento J (ed) L'archéologie française en Asie centrale[END_REF][START_REF] Tengberg | Environment and Subsistence Economies at Iron Age Ulug-depe, South-eastern Turkmenistan: First Results from the Archaeozoological and Archaeobotanical Studies[END_REF]). The plants were three samples of barley, most probably locally grown; one sample of willow, riverine and probably also locally grown; and one sample of tamarisk. The ratios ranged between 0.708191 and 0.708356 with an average of 0.708273 (± 0.000062), resulting in a local 87 Sr/ 86 Sr range for Dzharkutan of 0.708149 -0.708397 (±2σ, n = 9).

Fig. 3 :

 3 Fig. 3: 87 Sr/ 86 Sr signals from southern Central Asia; sites are in geographical order from west to east. Dashed boxes mark the determined local 87 Sr/ 86 Sr signals; the yellow box marks the calculated regional range (dark ±1σ, light ±2σ).

Fig. 4 :

 4 Fig. 4: Strontium isotope values of the geological units. Blue stars denote the isotopic values of Caspian Sea water. Values in red and green denote the local mean values obtained on rodents (Mus sp.) and barley (Hordeum vulg.) respectively.

Fig. 5 :

 5 Fig. 5: 87 Sr/ 86 Sr results of humans and references showing the variation between samples from the same individual. Tooth enamel samples are plotted with the sign of the particular gender as well as the colour of the date, bone samples are plotted as ̶ ̶ , dentine samples as X. Dashed boxes mark the determined local ranges, the yellow boxes mark the calculated regional range (dark ±1σ, light ±2σ). Abbreviations: ULG Ulug Depe, DZH Dzharkutan, TB Tilla Bulak, SD Sangir-tepe, EK Erkurgan.

Fig. 6 :

 6 Fig. 6: Human δ 18 O results out of apatite of bones and teeth with intra-individual variations: minus mark the bone samples, geometric signs mark tooth enamel samples (M3: full coloured, M n.d: striped). Coloured lines mark the averages, dashed boxes the averages ±1σ.

Fig. 7 :

 7 Fig. 7: Scatterplot correlation of δ 18 O vs. 87 Sr/ 86 Sr ratios of all analysed individuals. Abbr.: E stands for enamel, B for bones, ULG for Ulug Depe, DZH for Dzharkutan, G./D. for Gelot/Darnaichi. Dashed boxes mark the δ 18 O mean value out of human samples ±1σ in combination with the calculated local 87 Sr/ 86 Sr signals (±2σ). Big yellow boxes mark the inter-regional 87 Sr/ 86 Sr signal (dark ±1σ, light ±2σ).

  Depe and Dzharkutan were mainly sedentary with an intensive use of the surrounding landscape. The results revealed Ulug Depe during the early periods (EBA, EBA-MBA) with a high rate of immigration, four of six analysed individuals from these time periods did not fall within the local range. Remarkably, the individuals from the GKC phase showed little mobility and almost no immigration. Although this represents a time period of great changes, powerful empires and widespread networks, it seems the inhabitants of Ulug Depe and Dzharkutan remained local. The mobility pattern of Dzharkutan people was different; analyses displayed homogeneous clusters on the upper and lower limit of the local ranges. The results suggest complex patterns of mobility or subsistence, where movements between a person's place of birth/childhood and residence were a regular feature, observable throughout the centuries. The isotopic results of the other sites in the Surkhan Darya Valley and southern Tajikistan indicate active mobility and corroborate the known exchange of artifacts and technologies. However, the limited number of samples provides only a glimpse of the complex dynamics during Bronze Age in southern Central Asia and further studies are necessary to confirm or broaden the obtained insights.

Period approximate date cal. BCE Phase Kopet Dagh Mountains Surkhan Darya Valley Yakh-Su Valley Nuratau Range

  . Also, the Yakh-Su River Valley is covered by deep loess deposits, which are up to 200 m thick[START_REF] Teufer | Spätbronzezeitliche Grabfunde aus Nordbaktrien und benachbarten Regionen. Studien zur Chronologie zwischen Aralsee und Persischem Golf. AIT 13. Teufer M[END_REF]. The geological formation of Turkmenian cretaceous rocks and carbonates in the

	Late Bronze Age	2000-1600	NMG VI	Ulug Depe	Bustan Dzharkutan Tilla Bulak Sapallitepa	Darnaichi Gelot/ Saridzhar	Bashman 1
	Middle Bronze Age	2400-2000	NMG V	Ulug Depe	Dzharkutan	Gelot/ Darnaichi
	Early Bronze Age	2800-2400	NMG IV	Ulug Depe

  by expanding the mean value with 2σ. The itemized results of the faunal and botanical references, including the calculated local 87 Sr/ 86 Sr ranges, are listed in table 2; the two human dentine results can be found in table 3; all 87 Sr/ 86 Sr ranges are shown in fig. 3.

Table 2 87

 2 Sr/ 86 Sr results of botanical and faunal references and calculation of the local signals

	Local Sr/ Sr range ±2σ	(±0.001)																	0.707466 -0.709469	(0.707467 -0.709467)
	Mean ±1σ (n=34)																	0.708467 ± 0.000501
	Mean ±1σ Local Sr/ Sr range ±2σ						0.707954 ± 0.000045 0.707874 -0.708054										0.708273 ± 0.000062 0.708149 -0.708397								0.708918 -0.708978 0.708948 ± 0.000015				0.708859 ± 0.000379 0.708102 -0.709616				0.709362 ± 0.000062 0.709238 -0.709485
	Material Sr/ Sr ±2σ (last digits)	bone fragm. 0.707922 ± 06	bone fragm. 0.707885 ± 04	bone fragm. 0.707972 ± 07	bone fragm. 0.707908 ± 05	bone fragm. 0.707961 ± 03	charred wood 0.708016 ± 04	charred wood 0.708045 ± 03	charred seeds 0.707955 ± 05	charred seeds 0.70796 ± 05	charred seeds 0.707963 ± 06	charred seeds 0.707911 ± 05	bone fragm. 0.708201 ± 05	bone fragm. 0.708204 ± 03	charred wood 0.708312 ± 09	charred wood 0.708191 ± 04	charred seeds 0.708258 ± 06	charred seeds 0.708359 ± 06	charred seeds 0.708259 ± 07	tooth dentine 0.708330 ± 05	tooth dentine 0.708346 ± 05	charred seeds 0.708965 ± 03	charred seeds 0.708931 ± 13	charred seeds 0.708959 ± 06	charred seeds 0.708968 ± 08	charred seeds 0.708944 ± 04	charred seeds 0.70893 ± 11	charred seeds 0.708937 ± 07	bone fragm. 0.709237 ± 04	bone fragm. 0.70848 ± 11	bone fragm. 0.708273 ± 03	bone fragm. 0.709224 ± 06	tooth dentine 0.709297 ± 05	tooth dentine 0.709343 ± 05	tooth enamel 0.709445 ± 07
	Period	MBA	MBA	MIA	EBA/MBA		MBA	MIA	EBA	EBA	MBA	MIA	LBA	LBA	EIA	LBA	LBA	LBA	EIA	LBA	LBA	LBA	LBA	LBA	LBA	LBA	LBA	LBA	IA	IA	BA	BA	LBA	LBA	LBA
	Site Species Name of sample #Ref	Mus spec. R-CH. 1 Chantier 1	Mus spec. R-CH. 5 Chantier 5	Mus spec. R-CH. 16 Chantier 16	Canis fam. SK16-18 Chantier 1; 2007	Panthera spec. SK16-25 Chantier 5; 2004	Tamaris spec. SK18-01 Chantier 1 Est Ulug Depe	Juniperus spec. SK18-02 Chantier 8, US 8350	Hordeum vulg. SK18-03-1 Chantier 5, US 5012	Hordeum vulg. SK18-03-2 Chantier 5, US 5012	Hordeum vulg. SK18-04 Chantier 1 Est	Hordeum vulg. SK18-05 Chantier 8, US 8305	Mus spec. R-DZH 1066 Sep. 1066	Mus spec. R-DZH 2012 Excavation 2012	Chantier 7, US 7018 Tamaris spec. SK18-86	Chantier 7, US 7034 Salix spec. SK18-07	Chantier 7, US 7034 Hordeum vulg. SK18-09-1 Dzharkutan	Chantier 7, US 7034 Hordeum vulg. SK18-09-2	Chantier 7, US 7018 Hordeum vulg. SK18-10	DZH-2011 Sep1049 Homo sap. DZH 1049	DZH-2011 Sep1051 Homo sap. DZH 1051	TB10-KF-541 Triticum aest. SK18-76	TB10-KF-701 Triticum aest. SK18-77	TB10-KF-935 Triticum aest. SK18-80	TB09-KF-626 Hordeum vulg. SK18-75 Tilla Bulak	TB10-KF-890 Hordeum vulg. SK18-78	TB10-KF-919 Hordeum vulg. SK18-79	TB10-KF-937 Hordeum vulg. SK18-81	SK18-28 Mus spec. Geoktchik	SK18-115 Mus spec. Depe	SK18-31 Erkurgan Mus spec.	ST-04 -03 delta 3 pit SK18-32 Sangir-tepe Mus spec.	SK18-119 Homo sap.	SK18-120 Homo sap. Bashman 1	SK18-120 Homo sap.

Table 4

 4 Material and results of 87 Sr/ 86 Sr and δ 18 O of human and animals from southern Central Asia*

	bone compacta/tooth dentine
	tooth enamel

*Abbreviations: f: female; m: male; n.d.: not determined; M: Molar, C: Canine, I: Incisor. "M" or "bone. fragm." stand for samples where the determination was unsure, especially when samples were very little; "adult" stand for individuals where the preservation did not allow a further age determination; "child" stand for children below 14 years, but the preservation also did not allow a further age determination.

  [START_REF] Luneau | La fin de la civilisation de l'Oxus. Transformations et recompositions des sociétés de l'âge du Bronze final en Asie centrale méridionale (1800-1500/1400 avant n.è[END_REF] 7), due to the fact that all bone samples fell within very narrow ranges. The 87 Sr/ 86 Sr ratios of tooth enamel indicate that the EBA was a period of high immigration. None of the three analysed adult enamel 87 Sr/ 86 Sr ratios are in the local range of Ulug Depe. Burial 56 did not even lie within the calculated strontium signal of southern Central Asia, indicating a more distant origin (figs.[START_REF] Luneau | La fin de la civilisation de l'Oxus. Transformations et recompositions des sociétés de l'âge du Bronze final en Asie centrale méridionale (1800-1500/1400 avant n.è[END_REF] 7). Interestingly, especially the five individuals from the GKC (MBA) showed a distinct homogeneity in the 87 Sr/ 86 Sr and δ 18 O ratios. The δ 18 O ratios of all Ulug

	humans ranged between -6.9‰ and -2.4‰ with a range of 4.5‰ (enamel: 3.6‰; bones: 2.5‰) and
	average of -4.0‰ (± 1.0‰ n = 22) (fig. 6), suggesting a generally hot and arid climate in this region
	during the Bronze Age

Acknowledgements

We address our first acknowledgments to the Mission archéologique Franco-Ouzbèke Protohistoire (MAFOuz-P), the Mission archéologique franco-turkmène (MAFTur), the French Ministry of Foreign Affairs (MEAE), the French embassies in Turkmenistan and Uzbekistan, the French Archaeological Delegation in Afghanistan (DAFA), the Turkmenistan Directorate for the Protection, Study and Conservation of Historical and Cultural Heritage, the Directorate of the Archaeological Park of Abiwerd (Turkmenistan), the German Archaeological Institute´s missions in Tajikistan and Uzbekistan (with funding provided by the DFG, German Research Foundation, project number 392943887), and the Munich University mission to Tilla Bulak (with funding provided by the Gerda Henkel Foundation). Their support has made the excavations possible, upon which the present work is based. Additionally, we would like to thank the Mission Archéologique Franco-Ouzbèke de Sogdiane (MAFOUZ-Sogdiane) and the Archaeological Institute of Samarkand for authorizing the use of comparative samples.Moreover, we are grateful to the Laboratory AASPE UMR 7209 of the Museum National d'Histoire Naturelle in Paris and the Laboratory of Geoscience in Montpellier for hosting our project. Finally, special thanks should be addressed to the reviewers for their inspiring and constructive comments and to Prof. Michael Roaf for his personal review and the English editing.

provision of samples, project administration, funding acquisition, conceptualization, writing -review and editing

Fundings:

The isotopic analyses were kindly funded by the LIA HAOMA -CNRS Project, the Nestlé Foundation (Grant N° SJ866-17), the Shelby White and Leon Levy Program for Archaeological Publication, and the INSU-MITI-ILIADE project. Travelling and accommodation costs of the first author were liberally funded by the French Archaeological delegation in Afghanistan (DAFA).