Stone adzes production in Tupua'i (Austral islands, French Polynesia): Specialisation in a changing chiefdom of Central Eastern Polynesia [Production des lames d'herminette dans l'île de Tupua'i (Archipel des Australes, Polynésie française): ...]

La lame d'herminette en pierre, élément ubiquiste des cultures matérielles polynésiennes, a toujours été utilisée pour établir une périodisation des séquences culturelles pré-européennes. Bien que cette approche ait permis d'aborder la diversité des traditions culturelles et de définir une typo-chronologie des occupations pré-européennes dans la région, très peu de travaux ont pris en compte les aspects techno-économiques liés à la production de cet outillage. Cet article concerne la production des herminettes en Polynésie centre-orientale dans la première moitié du deuxième millénaire de notre ère, et se base sur les avancées théoriques et méthodologiques développées au sein de l'école française de l'anthropologie des techniques (aussi connue comme "technologie culturelle"). En nous basant sur l'analyse de plusieurs chaînes opératoires de production des lames d'herminette dans l'île de Tupua'i (Archipel des Australes, Polynésie Française), nous mettons en évidence des stratégies et des choix relativement complexes liés à la variabilité technique et l'organisation spatiale des chaines opératoires mises en œuvre, l'accès aux matières premières de qualité (en l'occurrence les basaltes à grains fins) et la présence d'artisans spécialisés.Enfin, nous traitons du rôle joué par le phénomène de spécialisation artisanale dans l'évolution des anciennes chefferies polynésiennes et proposons de considérer l'investigation approfondie des systèmes techniques comme un moyen efficace pour mettre en évidence des indices de la complexité sociale.1. IntroductionStone adze blades are so ubiquitous in the Pacific that they have always been central to the work of archaeologists. Polynesian adze heads were often viewed as convenient “cultural fossils” displaying stylistic features that could be used as chronological markers (e.g. Davidson 1984; Duff 1977; Suggs 1961) or to infer inter-island relationships (Duff 1960; Emory 1968; Sinoto 1970). The typological approach developed throughout the 20th century thus proved useful for understanding the archaeological diversity in the Pacific. Yet, it rarely took into account the environmental or technical contexts involved in the production of these artefacts. A broader technological turn began in the 1970’s (Cleghorn 1982; 1986; Leach 1980; 1984), which has led to better understanding of the technical and economic dimensions involved in Polynesian stone tool production.In this paper, I propose an integrated method to the study of stone tool technology and socio-economic evolution in Polynesian chiefdoms. My approach draws on the ‘research program’ which was set up by a group of French anthropologists (Cresswell 1976; Lemonnier 1983; 1986) to emphasize the systemic and multi-scalar dimensions of technical activities and to identify the fundamental role of techniques and production activities in the performance and evolution of societies. The work presented here was conducted during my PhD research, and therefore represents a first step in a wider research program that will be address with the dynamics of stone tool production at the inter-site scale, in different Polynesian islands. 2. Background and MethodologyAs a first step, each rock material was assigned a specific geological feature using a set of different geochemical analyses (Hermann et al. 2012; 2016). I used these results, combined with macroscopic identification of each artefacts, to track the spatial distribution of production processes (“chaînes opératoires”) within two sites dating from the early 13th to the late 15th century AD and considered as part of the same “technical transect” (Coupaye 2015) on the northern coast of Tupua’i island (Austral archipelago, French Polynesia). Both sites were discovered within the main pre-Contact district of the island, named Toerauetoru (Aitken 1930: 31-32): the Tanataetea site consists of a quarry and several workshops where basanite prisms have been quarried and transformed in great quantity, and the Atiahara site is a domestic occupation involving small thatched houses known from the ethnographical period as ‘arepota’ata (Hermann et al. 2016). I propose a thorough description of technological patterns in the making of adze heads in these two sites, not only through the description of finished products, but also through the identification of other artefacts including discarded preforms, roughouts, and other flake wastes, each representing combined sets of gestures constitutive of each sequence in the overall process of production. For every sequence, I investigated four main parameters interacting with one another: the nature of the raw material selected and its physical properties (fine or coarse-grained, natural flaws, etc.), the individual involved (including the inherited and acquired know-how, the technical traditions, economic choices, etc.), the tools and techniques performed (physical actions, mechanical procedures, etc.), and the spatial-temporal dimension of the process (concentrated in one site or segmented in space). These intrinsic properties are subject to change in different processes, however in this case they could be described through direct macroscopic observations, and interpreted thanks to experimental tests previously performed with the help of archaeologist and experimenter Florent Le Mené. The extrinsic properties of production processes are eventually be inferred. This last step of the analysis regarding the scarcity or uneven distribution of resources, the social environment, and the social status of craftsmen, provides the greatest insight into the evolution of the traditional Polynesian chiefdoms. 3. Results In East Polynesian islands stone adzes were produced by both specialists and non-specialists; the assemblages from Tupua’i show very clear differences in terms of technical skills, production intensity, and formal standards of the finished products, as an example of this technical split. While the craftsmen working in the Tanataetea workshops were producing big, standardised adzes with fine knapping techniques and were displaying anticipation as well as good risk management skills; the stone knappers of the domestic site at Atiahara only managed to produce only small flake adzes and appear to have maintained and recycled adzes produced elsewhere (including in the Tanataetea workshops). They therefore did not display any skills involving adapted percussion techniques or reaction facing flaking accidents, such as hinging or plunging fractures.At a diachronic level, the technological investigation suggests a significant evolution in the organisation of stone adze production in Tupua’i during the 14th century AD, with an increase of specialised production, as visible in the Tanataetea workshops, towards other sites from the same local chiefdom. The limited distribution of good-quality material in non-specialised sites like the domestic occupations of Atiahara also implies an increase in political control over key resources. 4. Discussion and conclusionThe general development of craft specialisation in the limited context of Tupua’i echoes previous observations from other parts of Polynesia (Cleghorn 1982; 1986; Leach 1993; Winterhoff 2007), and further reinforce the hypothesis of a strong correlation between technical specialisation and social complexity (Brun et al. 2006). This interpretation also fits the view of an increasing hierarchy among Polynesian chiefdoms where social and religious elites took control over different groups of specialists during the first half of the second millennium AD (Kirch 1984). I propose that the emerging view in the evolution of Polynesian craft production can also be explained in Sahlins’ terms of the “inflexion of the domestic mode of production” (Sahlins 1976). This model predicts that the intensification of production in traditional chiefdoms is driven by new economic choices prioritising centralisation and collaboration between households. Therefore, I propose that a heuristic approach of viewing material culture through the technological approach of chaînes opératoires is a promising method for investigating these patterns on the longue durée and across different Polynesian regions

Pofatu, a curated and open-access database for geochemical sourcing of archaeological materials

Compositional analyses have long been used to determine the geological sources of artefacts.Geochemical “fingerprinting” of artefacts and sources is the most effective way to reconstruct strategies of raw material and artefact procurement, exchange or interaction systems, and mobility patterns during prehistory. The efficacy and popularity of geochemical sourcing has led to many projects using various analytical techniques to produce independent datasets. In order to facilitate access to this growing body of data and to promote comparability and reproducibility in provenance studies, we designed Pofatu, the first online and open-access database to present geochemical compositions and contextual information for archaeological sources and artefacts in a form that can be readily accessed by the scientific community. This relational database currently contains 7759 individual samples from archaeological sites and geological sources across the Pacific Islands. Each sample is comprehensively documented and includes elemental and isotopic compositions, detailed archaeological provenance, and supporting analytical metadata, such as sampling processes, analytical procedures, and quality control

Coulomb-mediated antibunching of an electron pair surfing on sound

Electron flying qubits are envisioned as potential information link within a quantum computer, but also promise -- alike photonic approaches -- a self-standing quantum processing unit. In contrast to its photonic counterpart, electron-quantum-optics implementations are subject to Coulomb interaction, which provide a direct route to entangle the orbital or spin degree of freedom. However, the controlled interaction of flying electrons at the single particle level has not yet been established experimentally. Here we report antibunching of a pair of single electrons that is synchronously shuttled through a circuit of coupled quantum rails by means of a surface acoustic wave. The in-flight partitioning process exhibits a reciprocal gating effect which allows us to ascribe the observed repulsion predominantly to Coulomb interaction. Our single-shot experiment marks an important milestone on the route to realise a controlled-phase gate for in-flight quantum manipulations

Generation of a single-cycle acoustic pulse: a scalable solution for transport in single-electron circuits

The synthesis of single-cycle, compressed optical and microwave pulses sparked novel areas of fundamental research. In the field of acoustics, however, such a generation has not been introduced yet. For numerous applications, the large spatial extent of surface acoustic waves (SAW) causes unwanted perturbations and limits the accuracy of physical manipulations. Particularly, this restriction applies to SAW-driven quantum experiments with single flying electrons, where extra modulation renders the exact position of the transported electron ambiguous and leads to undesired spin mixing. Here, we address this challenge by demonstrating single-shot chirp synthesis of a strongly compressed acoustic pulse. Employing this solitary SAW pulse to transport a single electron between distant quantum dots with an efficiency exceeding 99%, we show that chirp synthesis is competitive with regular transduction approaches. Performing a time-resolved investigation of the SAW-driven sending process, we outline the potential of the chirped SAW pulse to synchronize single-electron transport from many quantum-dot sources. By superimposing multiple pulses, we further point out the capability of chirp synthesis to generate arbitrary acoustic waveforms tailorable to a variety of (opto)nanomechanical applications. Our results shift the paradigm of compressed pulses to the field of acoustic phonons and pave the way for a SAW-driven platform of single-electron transport that is precise, synchronized, and scalable.Comment: To be published in Physical Review

Development of a hard X-ray delay line for X-ray photon correlation spectroscopy and jitter-free pump–probe experiments at X-ray free-electron laser sources

A prototype device capable of splitting an X-ray pulse into two adjustable fractions, delaying one of them with the aim of performing split pulse X-ray photon correlation spectroscopy and pump–probe type studies was designed and manufactured. Time delays up to 2.95 ns have been demonstrated. The achieved contrast values of 56% indicate a feasibility of performing coherence-based experiments with the delay line

Mosaic: A Satellite Constellation to Enable Groundbreaking Mars Climate System Science and Prepare for Human Exploration

The Martian climate system has been revealed to rival the complexity of Earth\u27s. Over the last 20 yr, a fragmented and incomplete picture has emerged of its structure and variability; we remain largely ignorant of many of the physical processes driving matter and energy flow between and within Mars\u27 diverse climate domains. Mars Orbiters for Surface, Atmosphere, and Ionosphere Connections (MOSAIC) is a constellation of ten platforms focused on understanding these climate connections, with orbits and instruments tailored to observe the Martian climate system from three complementary perspectives. First, low-circular near-polar Sun-synchronous orbits (a large mothership and three smallsats spaced in local time) enable vertical profiling of wind, aerosols, water, and temperature, as well as mapping of surface and subsurface ice. Second, elliptical orbits sampling all of Mars\u27 plasma regions enable multipoint measurements necessary to understand mass/energy transport and ion-driven escape, also enabling, with the polar orbiters, dense radio occultation coverage. Last, longitudinally spaced areostationary orbits enable synoptic views of the lower atmosphere necessary to understand global and mesoscale dynamics, global views of the hydrogen and oxygen exospheres, and upstream measurements of space weather conditions. MOSAIC will characterize climate system variability diurnally and seasonally, on meso-, regional, and global scales, targeting the shallow subsurface all the way out to the solar wind, making many first-of-their-kind measurements. Importantly, these measurements will also prepare for human exploration and habitation of Mars by providing water resource prospecting, operational forecasting of dust and radiation hazards, and ionospheric communication/positioning disruptions

Lithic industries of Central Polynesia : know-how and techno-economic dynamics

En raison de leur ubiquité dans les assemblages archéologiques et les collections ethnographiques, les lames d’herminette en pierre ont longtemps été utilisées comme « fossiles-directeurs » afin de mettre en évidence des corrélations typo-chronologiques en Océanie. Néanmoins, les critères d’observations formels utilisés dans cette approche typologique ne permettaient pas de rendre compte de la complexité des processus techniques de fabrication. Après avoir rappelé les autres études expérimentales réalisées précédemment dans la région, nous proposons un premier référentiel des stigmates de taille sur roches basaltiques qui nous permet d’identifier différentes techniques de percussion utilisées dans la confection des lames d’herminette en pierre. La restitution des activités techniques qui ont abouti à la production de ces outils a été réalisée à travers l’analyse technologique d’assemblages archéologiques (produits finis ou semi-finis et déchets de taille) récoltés dans différentes sites de la côte Nord de l’île de Tubuai (Archipel des Australes, Polynésie Française). La caractérisation géochimique des gîtes géologiques et des artefacts taillés découverts en contexte archéologique a permis de restituer la répartition spatiale des différentes séquences de production au sein d’une même communauté ainsi que les transferts d’objets produits dans d’autres archipels. Parmi les différents réseaux d’approvisionnement identifiés dans l’île, j’ai choisi de suivre les activités techniques présentes au sein de deux sites : le premier est un complexe spécialisé dans la production des outils en pierre associant carrière d’extraction et ateliers de transformation, et l’autre un site d’habitat côtier.A travers la restitution des dynamiques de production, d’entretien et d’échange des lames d’herminettes en pierre, nous proposons un nouveau regard sur l’économie traditionnelle des chefferies de Polynésie centrale. Dans les assemblages étudiés, la confection de lames d’herminette a été essentiellement réalisée à travers la production d’éclats utilisés comme supports et transformés par façonnage. Cette combinaison des processus de débitage et de façonnage semble correspondre à une tradition technique qui prend son origine en Polynésie occidentale et qui est identifiée dans tous les archipels de Polynésie orientale. A partir des collections étudiées à Tubuai, il est possible de distinguer une production très standardisée de grandes lames au sein des ateliers spécialisés, et une production très peu standardisée de petites lames au sein des habitats côtiers. Grâce à la restitution des processus de production existant au sein d’une même communauté et des échanges intercommunautaires effectués à longue distance, nous discutons le rôle économique des herminettes à lame de pierre dans les chefferies polynésiennes.The ubiquity of stone adze blades in archaeological sites and museum collections resulted in their use as “cultural fossils” to draw cultural evolutionary changes in the Polynesian islands. The typological approach proves useful for understanding the archaeological diversity in Oceania. Yet, it lacks efficiency when it comes to shedding light on the technical and economic choices involved in the production processes.After a discussion of previous knapping experimentations performed in Polynesia, I propose a panel of diagnostic criteria for identifying the use of hard and soft hammerstone in the manufacture of adze blades. Then, I focus on the production of blades from assemblages collected on the North coast of Tubuai Island (Austral Archipelago, French Polynesia). Along with the need to consider the whole manufacturing process and the post-production exchange networks comes the necessity to connect different archaeological assemblages. Geochemical characterisation of the geological sources and artefacts discovered within archaeological contexts were used to settle the favoured framework for understanding the series of production sequences and for identifying the transfer of tools produced within and outside the island. Among the different supply networks identified on the island, I chose to investigate the operational sequences located within two sites: a quarry complex involving several workshops and a coastal dwelling site.Through the investigation of manufacture, maintenance and exchange processes regarding stone adze blades, I propose a new insight on the economic system in the chiefdoms of central Polynesia. The technical tradition documented on Tubuai is related to the production and transformation of flakes used as blanks for adze blades manufacture. This association of flaking and shaping processes originated in Western Polynesia but was also spread over Eastern Polynesia. The size and the form of these adzes were directly linked to one’s capacity for producing standard-sized blanks and for shaping specific blades forms. Based on the Tubuai collections, I identified a highly standardised production related to specialist knappers’ workshops, as well as a production of heterogeneous forms of small adze blades within a non-specialised dwelling context. Thanks to the analysis of the production processes within the community and the long-distance intercommunity exchanges, I finally discuss the economic role of stone adzes in ancient Polynesian chiefdoms

Dynamique de peuplement et évolution des réseaux d’échange à longue distance en Océanie

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Archéométrie des systèmes d’échange Polynésiens : un état des lieux

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Archéologie de Tupua'i : Bilan des travaux et perspectives de recherche

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