Showing papers in "Journal of Archaeological Method and Theory in 2018"

Searching for Lazy People: the Significance of Expedient Behavior in the Interpretation of Paleolithic Assemblages

Abstract: A quick glance at the evolution of lithic assemblages throughout prehistory highlights a great variability in the time and effort invested in technological activities. This variability has been related to differences in the technological organization of human groups, giving rise to the distinction proposed by Binford between curated and expedient technologies. Curation has been the subject of much discussion with regard to its definition and archaeological implications, but expediency has received comparatively less interest from researchers. Nevertheless, expedient technologies are ubiquitous in the archaeological record and represent a large proportion of prehistoric lithic assemblages, even becoming clearly dominant in certain chronological and/or regional contexts. The aim of this paper is to characterize expedient technologies as low-cost strategies that can be identified in all the stages of the lithic production sequence, from raw material provisioning to tool manufacture. However, we will focus our attention on core reduction technologies, emphasizing the consequences of distinguishing between expedient and formal reduction strategies. Finally, some implications of expediency in archaeological interpretation will be discussed, focusing on the significance of expedient technologies in the cultural ascription of lithic assemblages.

Experimental design and experimental inference in stone artifact archaeology

Abstract: Lithic researchers rely heavily on experimentation to infer past behaviors and activities based on stone artifacts. This paper explores the analogical nature of archaeological inference and the relationship between experimental design and inference validity in stone artifact experimentation. We show that actualistic flintknapping lacks vital aspects of scientific experimentation, and thus has inherent inferential issues of analogical adequacy and confidence. It is argued that a greater emphasis on hypothesis construction and variable control is needed in order to establish sound referential linkages upon which constructive analogic inferences about the past can be built.

Reconstructing Archaeological Networks with Structural Holes

Abstract: Model-based reconstruction is an approach to infer network structures where they cannot be observed. For archaeological networks, several models based on assumptions concerning distance among sites, site size, or costs and benefits have been proposed to infer missing ties. Since these assumptions are formulated at a dyadic level, they do not provide means to express dependencies among ties and therefore include less plausible network scenarios. In this paper we investigate the use of network models that explicitly incorporate tie dependence. In particular, we consider exponential random graph models, and show how they can be applied to reconstruct networks coherent with Burt's arguments on closure and structural holes (Burt 2001). The approach is illustrated on data from the Middle Bronze Age in the Aegean.

Sequential Incisions on a Cave Bear Bone from the Middle Paleolithic of Pešturina Cave, Serbia

Abstract: We present the detailed analysis of a cervical vertebra from a cave bear, found at Pesturina cave, Serbia, in a Mousterian archaeological level dated by radiocarbon at 43.5–44.6 kyr cal BP, and by ESR to between 93.5 and 102.5 kyr BP. Identified as a portion of the cranial articular facet, the fragment displays ten subparallel grooves. The microscopic study of these grooves and other surface modification present on the bone fragment, conducted with multifocus optical and confocal microscopes and complemented by a taphonomic analysis of the associated faunal assemblage, supports the hypothesis that the incisions were made by humans. Results are used to critically examine ambiguities implicit in the analysis and interpretation of early engravings, a category of material culture that has been playing a key role in the identification of early instances of symbolically mediated behavior.

Surfaces from the Visual Past: Recovering High - Resolution Terrain Data from Historic Aerial Imagery for Multitemporal Landscape Analysis

Abstract: Historic aerial images are invaluable sources of aid to archaeological research. Often collected with large-format photogrammetric quality cameras, these images are potential archives of multidimensional data that can be used to recover information about historic landscapes that have been lost to modern development. However, a lack of camera information for many historic images coupled with physical degradation of their media has often made it difficult to compute geometrically rigorous 3D content from such imagery. While advances in photogrammetry and computer vision over the last two decades have made possible the extraction of accurate and detailed 3D topographical data from high-quality digital images emanating from uncalibrated or unknown cameras, the target source material for these algorithms is normally digital content and thus not negatively affected by the passage of time. In this paper, we present refinements to a computer vision-based workflow for the extraction of 3D data from historic aerial imagery, using readily available software, specific image preprocessing techniques and in-field measurement observations to mitigate some shortcomings of archival imagery and improve extraction of historical digital elevation models (hDEMs) for use in landscape archaeological research. We apply the developed method to a series of historic image sets and modern topographic data covering a period of over 70 years in western Sicily (Italy) and evaluate the outcome. The resulting series of hDEMs form a temporal data stack which is compared with modern high-resolution terrain data using a geomorphic change detection approach, providing a quantification of landscape change through time in extent and depth, and the impact of this change on archaeological resources.

Monitoring the Environmental Risks Around Medinet Habu and Ramesseum Temple at West Luxor, Egypt, Using Remote Sensing and GIS Techniques

Abstract: Today, the preservation of cultural heritage is a pressing issue especially for territories subjected to a long period of human action that could adversely influence environment and heritage properties, thus producing a deterioration of archaeological features and alteration of historical landscape. In this paper, the environmental risks and their effects on preservation issues are investigated for the archaeological area of the Luxor city (south of Egypt) where the most famous Temples in Egypt are located. A comprehensive analysis has been conducted for the Ramesseum and Medinet Habu temples considering their building material and characteristics, environmental (geological and hydrological) setting, and past and ongoing changes around the monument areas. Satellite multitemporal images have been used to detect all the changes mainly linked to the expansion of urban and agriculture areas. Results from the analysis conducted along with in situ investigations have suggested that many of the environmental problems around the archaeological areas are coming as a result of urban and agriculture sprawling. Both of them strongly influence the distribution in the levels of groundwater which along with temperature are considered as the main causes of the deterioration process affecting the Medinet Habu and Ramesseum temple. The degree of weathering damage appears to be much more dependent on exposure characteristics of the investigation areas, especially as related to salt weathering processes. Innovative solutions to support the preservation of these temples are herein presented and discussed.

Building an Experimental Comparative Reference Collection for Lithic Micro-Residue Analysis Based on a Multi-Analytical Approach

Abstract: Residue analysis applied to stone tools is a useful aid for better understanding their past function and, by extension, reconstructing early human behaviour. However, if the nature of residues found on the lithic tools is misinterpreted, so will be our understanding of their archaeological context. As a consequence, correctly identifying residues in the domain of lithic studies is of paramount importance. With this main goal in mind, we analysed different experimental materials likely to have been involved in daily tasks in the prehistoric context (e.g. bone, wood, meat). Microscopic analyses were then carried out using two (comparable) techniques: Optical Light Microscopy and Scanning Electron Microscopy. Also, energy dispersive X-rays spectroscopy (EDX or EDS) was applied to the experimental samples to determine their elemental composition. Advantages and disadvantages of both microscopic methods and their implications for correct residue identification are discussed. The distribution of residues on lithic surfaces is also considered. This study resulted in the construction of a data-set including both photographic material and EDX spectra for each residue analysed. The main result is that, compared to OLM scanning, SEM analyses highly improves the accuracy of residue identification.

Developing FTIR Microspectroscopy for the Analysis of Animal-Tissue Residues on Stone Tools

Abstract: The analysis of microscopic residues on stone tools provides one of the most direct ways to reconstruct the functions of such artifacts. However, new methods are needed to strengthen residue identifications based upon visible-light microscopy. In this work, we establish that reflectance Fourier-transform infrared microspectroscopy (FTIRM) can be used to document IR spectra of animal-tissue residues on experimental stone tools. First, we present a set of reflectance FTIRM standards for the most commonly identified animal-tissue residues on stone tools: skin, meat, fat, hair, blood, feather barbules, fish scales, and bone. We provide spectral peak assignments for each residue and demonstrate that high-quality reflectance FTIRM spectra can be generated under ideal circumstances. Second, we document the spectra for these residues when they are located on a stone substrate such as flint or obsidian. We discuss procedures for correcting spectra that are affected by specular reflection and explain the effects of spectral interference from the stone. Our results show that reflectance FTIRM is sensitive to small intra-sample differences in composition. This means that it will record the effects of decomposition in ancient residues. The methodological developments we present here will help lithic residue analysts incorporate in situ reflectance FTIRM into their analysis protocols to strengthen identifications.

Things and the Slow Neolithic: the Middle Eastern Transformation

Abstract: This paper argues that the search for an overarching explanation for the adoption of farming and settled life in the Middle East can be enhanced by a consideration of the dependencies between humans and human-made things from the Late Glacial Maximum onwards. Often not considered in discussions of the origins of agriculture is the long process of human tooth size reduction that started in the Upper Palaeolithic and can reasonably be related to the increased use of grinding stones that created softer and more nutrient-rich plant foods. A consideration of the use of groundstone tools through the Epipalaeolithic and into the Neolithic shows that they were entangled with hearths, ovens, houses and settlements, exchange relations and notions of ownership. The practicalities of processing plants drew humans into pathways that led to intensification, population increase, sedentism and domestication. Much the same can be said for other human-made things such as sickles, storage bins, domestic animal dung and refuse. The dialectical tensions between human-thing dependence and dependency generated the movement towards Neolithicization. Human-thing dependence (involving human dependence on things, thing dependence on humans and thing dependence on other things) afforded opportunities towards which humans (always already in a given state of entanglement) were drawn in order to solve problems. But this dependence also involved dependency, limitation and constraint, leading for example to increases in labour. In order to provide that labour or in other ways to deal with the demands of things and their entanglements with other humans and things, humans made further use of the affordances of things. There was thus a generative spiral leading to sedentism and domestication.

Refining the Maritime Foundations of Andean Civilization: How Plant Fiber Technology Drove Social Complexity During the Preceramic Period.

Abstract: Moseley’s (1975) Maritime Foundations of Andean Civilization hypothesis challenges, in one of humanity’s few pristine hearths of civilization, the axiom that agriculture is necessary for the rise of complex societies. We revisit that hypothesis by setting new findings from La Yerba II (7571–6674 Cal bp) and III (6485–5893 Cal bp), Rio Ica estuary, alongside the wider archaeological record for the end of the Middle Preceramic Period on the Peruvian coast. The La Yerba record evinces increasing population, sedentism, and “Broad Spectrum Revolution” features, including early horticulture of Phaseolus and Canavalia beans. Yet unlike further north, these changes failed to presage the florescence of monumental civilization during the subsequent Late Preceramic Period. Instead, the south coast saw a profound “archaeological silence.” These contrasting trajectories had little to do with any relative differences in marine resources, but rather to restrictions on the terrestrial resources that determined a society’s capacity to intensify exploitation of those marine resources. We explain this apparent miscarriage of the Maritime Foundations of Andean Civilization (MFAC) hypothesis on the south coast of Peru by proposing more explicit links than hitherto, between the detailed technological aspects of marine exploitation using plant fibers to make fishing nets and the emergence of social complexity on the coast of Peru. Rather than because of any significant advantages in quality, it was the potential for increased quantities of production, inherent in the shift from gathered wild Asclepias bast fibers to cultivated cotton, that inadvertently precipitated revolutionary social change. Thereby refined, the MFAC hypothesis duly emerges more persuasive than ever.

Application of Quantitative Mineralogical Analysis in Archaeological Micromorphology: a Case Study from Barrow Is., Western Australia

Abstract: This study assesses the use of the Tescan Integrated Mineral Analyser (TIMA) platform, which integrates scanning electron microscopy—energy dispersive spectroscopy (SEM-EDS) chemical analysis with mineral identification software, to quantitatively determine the mineralogical composition of sediments in archaeological research. Ten samples, spanning 50,000 years of sedimentation, were examined from archaeological excavation profiles in the Boodie Cave, Barrow Island, Western Australia. TIMA mineral abundance data show a gradual change from a polymineralogic quartz-rich assemblage from ~50–12 ka to a more simple carbonate-dominate assemblage from the terminal Pleistocene. This trend is consistent with a decreasing contribution of reworked terrestrial siliciclastic sediments derived from the mainland and an increase in carbonate sediments of marine derivation, as the exposed coastal plain become submerged during post-glacial sea-level rise. SEM-EDS analysis has also provided empirical data on cultural materials, mainly bone and shell fragments that similarly reflect the increasing contribution of marine fauna into the Holocene sediments. Particularly useful is the ability of mineral mapping function of the TIMA outputs to help distinguish 16 sub-units representing sections of the main nine stratigraphic units, including at least three contiguous midden events. The SEM-EDS data indicate that the redeposited sediments were derived from the overlying midden unit, with layering reflecting differential settling of mineral phases. This study demonstrates that automated mineralogy studies using TIMA can clearly aid the identification of provenance and processes within archaeological sediments and soils.

Core Use-Life Distributions in Lithic Assemblages as a Means for Reconstructing Behavioral Patterns

Abstract: Artifacts with varying use-lives have different discard rates and hence are represented unequally among archaeological assemblages. As such, the ability to gauge the use-lives of artifacts is important for understanding the formation of archaeological assemblage variability. In lithic artifacts, use-life can be expressed as the extraction of utility, or work potential, from existing stone volume. Using experimental data and generalized linear modeling, this study develops models of artifact use-life on cores in the form of reduction intensity. We then apply these models to two archaeological case studies to (a) reconstruct the reduction intensities of archaeological cores and (b) investigate the survivorship curves of these archaeological cores across the reduction continuum using the Weibull function. Results indicate variation in core reduction and maintenance with respect to raw material properties and place use history and implicate evolutionary differences between Early Stone Age hominins and Holocene modern humans.

A Sensory Update to the Chaîne Opératoire in Order to Study Skill: Perceptive Categories for Copper-Compositions in Archaeometallurgy

Abstract: This paper introduces the methodology of perceptive categories through which an empirical analysis of skill is achievable, taking European Bronze Age metalworking as a case study. Based on scientific data provided by the material sciences, in this case compositional and metallographic analyses of Late Copper Age and Early Bronze Age axes, the thresholds to categorise and interpret these data, and organise them in a chaine operatoire, are centred on the human senses—and thus on metalworking as a craft. This is a pragmatic approach that appreciates scientific measurements of metal objects as essential empirical evidence whilst recognising that a considerable share of these archaeometric data are inapt or too detailed for an understanding of skill. This empirical approach towards skill is relevant to our knowledge of the role of crafts and materials in the past. After all, skill is a fundamental asset for the production of material culture, and a distinct human-material relationship characterised by an intimate form of material engagement.

The Role of Fire in the Life of an Adhesive

Abstract: The use of fire is essential for the preparation of hafting adhesives; both are suggested to be a proxy for distinguishing the technological expertise and complex cognition among Palaeolithic populations. While use of fire has been argued to exist from about 1.0 Ma onwards, evidence for adhesives in the Palaeolithic record is rare and fragmented. In spite of the close link between fire places and adhesives, no study has ever focussed on examining the impact of heat on adhesive deposition and preservation. This paper discusses the results of a combustion experiment that was undertaken to understand the impact of heat exposure on hafting adhesives. The results have significant implications for archaeological interpretations. Deposition in or near a fire proves to severely impact the types of residues that preserve on a stone tool. The vertically transferred heat is responsible for the loss of adhesives but also for the incidental production of adhesives and their deposition on stone tools. It can be hypothesised that the rare survival of adhesives on archaeological stone tools might not only be the result of direct contact with the fire but also the result of degradation due to heat from overlying fireplaces. If we are to improve our understanding of the preservation of adhesives, it is important to unstand the taphonomic processes that affect these adhesives, in particular heat alteration.

Immersive Visualization and Curation of Archaeological Heritage Data: Çatalhöyük and the Dig@IT App

Abstract: Advanced data capture techniques, cost-effective data processing, and visualization technologies provide viable solutions for the documentation of archaeological heritage and material culture. Work at the UNESCO World Heritage site of Catalhoyuk has demonstrated that new digital approaches for capturing, processing, analyzing, and curating stratigraphic data in 3D are now feasible. Real-time visualization engines allow us to simulate the stratigraphy of a site, the three-dimensional surfaces of ancient buildings, as well as the ever-changing morphology of cultural landscapes. Nonetheless, more work needs to be done to address methodological questions such as follows: can three-dimensional models and stratigraphic relationships, based on 3D surfaces and volumes, be used to perform archaeological interpretation? How can a 3D virtual scenario become the interface to cultural data and metadata stored in external online databases? How can we foster a sense of presence and user embodiment in the simulation of ancient cities and archaeological sites? This article aims to provide viable solutions to the methodological challenge of designing a comprehensive digital archaeological workflow from the data acquisition and interpretation in the field to a three-dimensional digital data curation based on interactive visualization, searchable 3D data, and virtual environments. This work describes the results we achieved developing the application Dig@IT, a multi-platform, scalable virtual reality tool able to foster archaeological data analysis, interpretation, and curation in a realistic and highly interactive virtual environment.

Home Is Where the Hearth Is: Anthracological and Microstratigraphic Analyses of Pleistocene and Holocene Combustion Features, Riwi Cave (Kimberley, Western Australia)

Abstract: The manipulation of fire is a technological act. The identification of the archaeological signatures of the controlled use of fire has important implications not only for the estimations of the origins and functions of the first fireplaces but also for our understanding of prehistoric technological development and resource use. At Riwi (Kimberley region, Western Australia), excavations over two field seasons have revealed a discontinuous occupation sequence over the past 45 ka, showing numerous, different combustion features interspersed within the deposit. Anthracological and micromorphological investigations at Riwi Cave indicate that the combustion features at the site can be categorised into three types: flat combustion features (type A), dug combustion features (type B) and thick accumulations of mixed combustion residues (type C). These provide evidence for two kinds of combustion practice: (i) fires lit directly on the ground and most likely not re-used and (ii) ground ovens, the latter appearing some 10,000 years after the first evidence for occupation of the site. A comparison of the wood species identified within these combustion features with those from equivalent scattered context levels, enables an exploration of the potential factors influencing wood selection and fire use through time at the site. A detailed understanding of the relationship between wood charcoal remains and archaeological context yields significant information on changes to environmental context and site occupation patterns over time.

Complex Contagions and the Diffusion of Innovations: Evidence from a Small-N Study

Abstract: The recent literature on “complex contagions” challenges Granovetter’s classic hypothesis on the strength of weak ties and argues that, when the actors’ choice requires reinforcement from several sources, it is the structure of strong ties that really matters to sustain rapid and wide diffusion. The paper contributes to this debate by reporting on a small-N study that relies on a unique combination of ethnographic data, social network analysis, and computational models. In particular, we investigate two rural populations of Indian and Kenyan potters who have to decide whether to adopt new, objectively more efficient and economically more attractive, technical/stylistic options. Qualitative field data show that religious sub-communities within the Indian and Kenyan populations exhibit markedly different diffusion rates and speed over the last thirty years. To account for these differences, we first analyze empirically observed kinship networks and advice networks, and, then, we recreate the actual aggregate diffusion curves through a series of empirically calibrated agent-based simulations. Combining the two methods, we show that, while single exposure through heterophilious weak ties were sufficient to initiate the diffusion process, large bridges made of strong ties can in fact lead to faster or slower diffusion depending on the type of signals circulating in the network. We conclude that, even in presence of “complex contagions,” dense local ties cannot be regarded as a sufficient condition for faster diffusion.

Acoustic Measurements and Digital Image Processing Suggest a Link Between Sound Rituals and Sacred Sites in Northern Finland

Abstract: In northern Finland, near the canyon lakes of Julma-Olkky, Somerjarvi, and Rotkojarvi, steep rock cliffs produce distinctive acoustic spaces. On these cliffs, prehistoric rock paintings (5200 to 1000 BC) as well as an ancient Sami offering site (circa 1100 to present) can be found. Ethnographic sources describe that the Sami used to sing and listen to echoes while making offerings there. This article presents the results of an archaeoacoustic research project that seeks to explore the role of sound in the development and use of these archaeological sites. The innovative set of methods includes multichannel impulse response recording, angle-of-arrival estimation of early reflections, spectrum analysis, digital image processing, and 3D laser scanning. On the basis of the analyses, it is concluded that the cliffs that have been painted or held as sacred are efficient sound reflectors. They create discrete echoes and, accordingly, phantom sound sources. Especially at the Varikallio cliff near Lake Somerjarvi, the sound appears to emanate directly from the painted figures. These results, together with previously unnoticed drumming figures in the Varikallio painting, provide a clue to the significance of the sound rituals at these sacred sites.

Intermarriage, Technological Diffusion, and Boundary Objects in the U.S. Southwest

Abstract: This article draws upon ethnographic accounts of female potters’ movement and intermarriage into multi-ethnic Pueblo communities in the U.S. Southwest to illustrate how marriage networks created opportunities for innovation through the production, distribution, and consumption of boundary objects. These objects did not define boundaries but facilitated boundary crossing or bridging by potters. I argue that the concept of boundary objects is more useful than hybridity for understanding the processes of culture contact and material culture diffusion. Archaeological evidence for late twelfth through thirteenth century migrations from the Four Corners to the southern Colorado Plateau is used to make a case for a high degree of intermarriage and post-marital movement of women. Such patrilocality challenges normative views of post-marital residence, including those employed by early ceramic sociologists working in the same area of the Southwest and even at the same sites. The case that I discuss provides a contrast to other Southwest examples in which conformist transmission was more common, and helps to solve a paradox in explanations of the Southwest Pueblo Sprachbund. I conclude that the concept of boundary objects complements formal social network approaches in archaeology by bringing out the active role of objects in linking social actors.

Maya Crocodilians: Intersections of Myth and the Natural World at Early Nixtun-Ch’ich’, Petén, Guatemala

Abstract: This essay pursues a four-pronged, interdisciplinary approach in considering the possibility that the unusual layout of the lowland Maya site of Nixtun-Ch’ich’ in the lakes region of central Peten, Guatemala, might have been modeled on the scaly back of a crocodile. Part 1 summarizes the biological characteristics of crocodilians, particularly Crocodylus moreletii, and their habitats in lowland Mesoamerica. Part 2 reviews interpretations of these reptiles in myth and art, and exploitation of the creature in the lakes area. Third, the ceremonial core of Nixtun-Ch’ich’, established in the Middle Preclassic (800–400 BCE) period, is discussed. It exhibits an unusual grid of corridors creating a landscape resembling the bony plates of a crocodilian’s back, and a natural cenote-like fosa is proposed to relate to a mythical “Starry Deer Crocodile.” Part 4 discusses probable social and political characteristics of early community leaders who planned this site’s atypical layout, viewed through selectionist theories of cooperation and costly signaling. Designed to mimic the mythical crocodile of creation, Nixtun-Ch’ich’ illustrates the role of ideological power in the development of complex societies.

Between Monoculture and Cultural Polarization: Agent-based Models of the Interplay of Social Influence and Cultural Diversity

Abstract: Social influence is one of the most important processes in human social interaction. Very often in human social interaction, influence is assimilative in that individuals become more similar to others they interact with. Nevertheless, cultural differences continue to remain in many realms of human life, for example, in the form of technological boundaries. Research on social influence points to a range of possible reasons for persistent cultural diversity, but there is much less clarity about the interplay of various factors and conditions for cultural influence with fundamental processes of social interaction at the micro-level. In this article, I show how agent-based computational modeling can be used as an approach for unraveling the complex interplay between simple first principles of interpersonal social interaction and emergent societal outcomes. I give a brief overview illustrating some of the main approaches agent-based modelers have developed in recent decades to understand conditions and processes of the emergence of cultural diversity. Models will be discussed that generate mainly cultural consensus as long-term behavior, but also models that generate clustering of cultural attitudes in geographical or social space, and models that imply cultural polarization with sharp cultural boundaries between emergent factions. It will be discussed how model dynamics depend on further assumptions, for example about random events, or the scaling of cultural attitudes, and what are further developments in the literature, possible future directions and challenges for the application of computational agent-based modeling in archeological research on cultural boundaries.

Time-Averaging Slows Down Rates of Change in the Archaeological Record

Abstract: Measuring the pace of cultural change, and understanding its determinants is a fundamental goal of anthropological research. The archaeological record is the main source of information about the pace of cultural change, but it is an imperfect one, as taphonomic loss and mixing distort rate measurements. Here, I focus on the impact of time-averaging on rate measurements. Time-averaging arises when archaeological materials associated with activities and events that took place at different points in time are mixed into the same unit, whether because of depositional processes, disturbance factors, or because archaeologists lump together archaeological contexts when creating analytical units. I use analytical models to show how time-averaging can slow down the observed rates of change under two general modes of cultural change: random drift and directional change. I test this prediction using empirical rates of change from the archaeological record of North America. I show that empirical rates of change are indeed inversely correlated with the duration of time-averaging and provide a range estimate for this correlation.

The Evolution of Migration: the Case of Lapita in the Southwest Pacific

Abstract: Migrations have occurred across the history of the genus Homo and while the movement of pre-modern humans over the globe is typically understood in terms of shifting resource distributions and climate change, that is in ecological terms, the movement of anatomically modern, and specifically Holocene, populations is often explained by human desire to discover new lands, escape despotic leaders, forge trade relationships and other culture-specific intentions. This is a problematic approach to the archaeological and behavioural explanation of human migration. Here an evolutionary and ecological framework is developed to explain various movement behaviours and this framework is applied to the movement of human groups from the inter-visible islands around New Guinea to the widely dispersed archipelagos of the southwest Pacific about 1000 BC. Labelled the Lapita Migration, this movement is explained as a selection-driven range expansion. The development of evolutionary and ecological theory to explain human movement facilitates empirical testing of alternative hypotheses and links different histories of human movement through shared explanatory mechanisms.

Weak Ties and Expertise: Crossing Technological Boundaries

Abstract: In this article, we question how new technological traits can penetrate cohesive social groups and spread. Based on ethnographic narratives and following studies in sociology, the hypothesis is that not only weak ties are important for linking otherwise unconnected groups and introducing new techniques but also that expertise is required. In order to test this hypothesis, we carried out a set of field experiments in northern India where the kiln has been adopted recently. Our goal was to measure the degree of expertise of the potters distributed between early and late adopters of the kiln. Our results are discussed in the light of oral interviews. Our conclusions suggest that expertise is a necessary, albeit not sufficient, condition for weak ties to act as bridges and thereby for new techniques to spread. As an example, they explain how turntables could have been adopted by potters from the northern Levant during the third millennium BC.

Identifying Narrative Descriptions in Agent-Based Models Representing Past Human-Environment Interactions

Abstract: There is a growing use of bottom-up simulation models to reconstruct past human-environment interactions. Such detailed representations pose difficult questions not only in their design (the generality-realism trade-off) but also about the inferences that are made from them. The historical sciences are faced with seeking to make robust inferences from limited, potentially biased and/or incomplete samples from uncontrolled systems, and as a result have sometimes employed narrative explanation. By contrast, simulation models can be used experimentally and can generate large amounts of data. Here, using an agent-based model of hunter-gatherer foraging in a previously unexplored ecosystem, we consider how narratives might be identified from the trajectories produced by simulations. We show how machine learning methods can isolate qualitatively similar types of model behaviour based on summaries of model outcomes and time series. We stand to learn from this approach because it enables us to answer two questions: (i) under what conditions (representations and/or parameterisations) do we observe in the model what is recorded in the archaeological and/or palaeoenvironmental record? and (ii) does the model yield unobserved dynamics? If so, are they plausible? Using models to develop narratives is a logical extension of the bottom-up approach inherent in agent-based modelling and has the potential, alongside conventional methods of model evaluation, to aid in learning from the rich dynamics of such simulations.

Uranium and Vanadium Concentrations as a Trace Element Method for Identifying Diagenetically Altered Bone in the Inorganic Phase

Abstract: Archaeologists have generally avoided analyzing inorganic isotopes in bone because of its high porosity, large crystalline lattice spacing, and small crystallite size, making it particularly susceptible to diagenetic alteration. Because the inorganic isotopes are left unstudied, we lose a significant portion of information pertaining to an individual’s life history, such as migration, health, and ranging behavior. Tooth enamel, which does not have the same susceptibility to diagenesis as bone, can be used to extract this information but this means that taxa lacking teeth, such as birds, some species of fish, and some reptiles, are excluded. Here, we present a method that can be used to identify diagenetic alternation in bone. This is done by focusing on abnormal concentrations of vanadium and uranium. Neither element is readily bio-precipitated into hydroxyapatite due to ionic radius, vibrational frequency, atomic mass, and ionic charge. This makes them an ideal marker for diagenetically altered bone. Vanadium occurs in very low concentrations in modern bone, while archaeological bone shows clear evidence of normal, non-diagenetically altered values alongside high concentrations of vanadium in diagenetically altered bone. Uranium also is a measure of diagenetic alteration, as modern bone has concentrations below detectable limits (0.017 ppb), while some archaeological bone contains uranium above detectable limits. The biogeochemistry of these elements in soil and bone are discussed with implications for enamel studies.

Task-Specific Sites and Paleoindian Landscape Use in the Shaw Creek Flats, Alaska

Abstract: The Shaw Creek Flats and nearby middle Tanana river, in central Alaska, constitute one of the areas in the Americas with the densest known distribution of Late Glacial (about 14,500–11,700 cal. B.P.) archaeological sites. Local high rates of sediment deposition and low post-depositional disturbance allow for the interpretation of the function of archaeological occupations within larger economic and mobility strategies. Residential sites used over the long term seem to be located near critical but immovable resources such as clear water and vegetation. The spatial association of artifacts and faunal remains at other sites in the Flats suggest that they were specialized, short-lived locations dedicated to a single or few activities. For instance, the site of Swan Point Cultural Zone 4b is interpreted as a workshop related to the production of composite tools, particularly on mammoth ivory, and the site of Keystone Dune is interpreted as a camp related to wapiti (Cervus elaphus) hunting. These task-specific sites and others were probably used as part of a predominantly logistical mobility and economy strategy, which maximized efficiency in harvesting and processing resources that were distributed heterogeneously on the landscape.

The Structural and Functional Complexity of Hunter-Gatherer Technology

Abstract: The complexity of hunter-gatherer technology has been measured by counting artifact parts or production steps. There are a variety of alternative approaches to the measurement of artifact or system complexity. If technological complexity is assumed to reflect the complexity of the problem (or amount of entropy reduction) that the artifact is designed to address, the most appropriate measure of technological complexity is functional design complexity, which entails application of the entropy formula from information theory to the making and using of an artifact and the results obtained by its use. Functional complexity is related to structural or hierarchical complexity, because the entropy formula can be represented as a hierarchy (or step-by-step reduction of entropy) and the functional differentiation is related to the structural differentiation of an artifact. Another approach to hunter-gatherer technological complexity entails definition of a class of “complex artifacts” on the basis of general design characteristics (e.g., incorporation of moving parts). The most structurally and functionally complex artifacts are those that possess multiple states, either through changes in the physical relationship between parts (or sub-parts) during use or through structural differentiation. Although functional complexity is difficult to measure, structural or hierarchical complexity may be measured—and multiple-state artifacts may be counted—with adequate ethnographic and archaeological data on hunter-gatherer technology.

Cultural Niche Construction and Remote Sensing of Ancient Anthropogenic Environmental Change in the North Coast of Peru

Abstract: Archaeological land use results in the modification of natural environments according to cultural templates and strategies. Deeply entrenched environmental legacies can result from such “niche construction,” influencing subsequent cultures and continuing to resonate in modern ecological function. These changes can be better understood through archaeological remote sensing. Here, I describe spectral responses of densely vegetated sugarcane fields in the Chicama Valley (north coast of Peru) to archaeological features and associated anthropogenic soils (anthrosols). Ongoing satellite remote sensing documents approximately 440 previously unrecorded major archaeological monuments and smaller features within a 310 km2 sample of the Chicama Valley The majority of these date to the Moche–Chimu periods (ca. AD 300–1400), with others dating to the Cupisnique–Colonial periods. The newly recorded features are significant for accurately reconstructing the socio-ecological history of anthropogenic environmental change in the region. In addition to advancing analyses of archaeological settlement, these results reveal how prehispanic land use legacies result in persistent anthropogenic niches that can affect modern agricultural potentials. The relationships between anthropogenic features and sugarcane development can be directly evaluated through vegetation indices and physically based image transforms. Phenological response is linked to long-term alterations in soil texture, organic-matter content, and moisture capacity. Past land use thus has a significant impact upon contemporary ecological function, resulting in anthropogenic microenvironments. As sugarcane increasingly is an important industrial crop, these results have the potential to be widely applied to archaeological and agronomic problems, including reconstructions of archaeological landscapes, understanding persistent anthropogenic environments, and mitigating heritage loss while potentially improving precision agriculture.

Toy Story: Homophily, Transmission and the Use of Simple Simulation Models for Assessing Variability in the Archaeological Record

Abstract: The interpretation of spatial and temporal patterns in the archaeological record remains a long-standing issue in the discipline Amongst many methods and interpretations, modelling of ‘biased transmission’ has proved a successful strategy to tackle this problem Here, we investigate a type of biased transmission, homophily, that is the tendency of individuals to associate and bond with similar others In contrast to other social sciences, homophily remains underused in archaeology In order to fill this gap, we develop six distinct variants of a well-established modelling framework borrowed from social science, Axelrod’s Cultural Dissemination Model These so-called toy models are abstract models used for theory-building and aim at exploring the interplay between homophily and various factors (eg addition of spatial features such as mountains and coastlines, diffusion of innovations and population spread) The relevance and implications of each ‘toy model’ for archaeological reasoning are then discussed