Instruments of authority: Tycho Brahe’s technological illustrations

ABSTRACT

The astronomical instruments of Danish astronomer, Tycho Brahe, were crucial to his intended reform of astronomy in the sixteenth century. Tycho represented these devices in a series of images that were circulated in range of contexts, thereby disseminating information about his technology to a wider audience. Through an analysis of the iconographical content of these images and a consideration of the ways in which they were circulated, this article argues that images of technology were in fact crucial to Tycho’s attempts to establish his authority as an astronomer. Embodying his claims to accuracy and recruiting trust in his innovative instruments, the images reinforced the validity of his astronomy and thereby played a central role in sustaining his reputation as an astronomer.     

The Hogeye Clovis cache,Texas: quantifying lithic reduction signatures

The Hogeye Clovis cache is comprised of 52 late-stage bifaces, finished points, and knife/cores cached in central Texas. Because these artifacts were all likely made and cached approximately 13,000 years ago by one or a handful of knappers belonging to a single band with a shared Clovis cultural template, Hogeye provides a rare opportunity to investigate Clovis lithic reduction signatures. This paper builds on previous analyses and presents new methods for quantifying Clovis biface production signatures, including serial flaking and the timing of last overshot flaking. The results show that the Hogeye cache bifaces technologically and morphologically differ from other regional Clovis biface reduction signatures. Additional data is needed to determine whether these differences reflect individual knapping preferences or regional cultural signatures. The methods used and developed here are not Clovis-specific and could be modified and combined with other analytical techniques to identify reduction signatures in biface assemblages from other times and places.     

Evaluating morphological variability in lithic assemblages using 3D models of stone artifacts

Technological and morphological variability in lithic artifacts is commonly used to identify taxonomic entities in Paleolithic research contexts. Assemblages are mainly studied using either linear distance measurements or qualitative assessments of morphologies. Here, we present a method to quantify morphological variability in lithic artifacts using 3D models of stone artifacts. Our study on the sequence of the Upper Paleolithic layers V–I from the site Yabroud II in western Syria, demonstrates that utilizing 3D models provides a new insight into the variability of lithic technologies. We use quantitative data on convexities, twist and scar patterns on cores and blades, attributes previously not readily quantifiable, to trace technological change through the archaeological sequence. We are able to identify differences and translate these findings into a grouping of the layers. While layers VI–II are characterized by technological continuity and were grouped together, layers V and I can be separated from this group and represent technologically different groups chronologically before and after. Our results demonstrate the potential of 3D models for studying morphological variability in lithic assemblages.     

Swept under the rug: the problem of unacknowledged ambiguity in lithic residue identification

Microscopic analysis of organic residues on stone tools is used to interpret prehistoric stone tool functions. The morphology of some residues can be difficult to interpret, yet this ambiguity is rarely acknowledged in the literature. Our research seeks to understand the nature of this ambiguity by objectively identifying ambiguous residues in our reference collection. We trained four archaeologists in residue analysis using one part of our reference collection, then tested their ability to identify sixty-eight residues in another part of the same collection. Forty-eight of the residues in the test (70%) were correctly identified by three or all four subjects. We considered the remaining twenty residues, which were correctly identified by two or fewer of the subjects, to be ambiguous. These are most often in the hide-scraping, bone-scraping, and hardwood-scraping (macerated) categories, and tend to have an atypical morphology which falls in the range of variability of another residue category. Some of these residues also have optical properties which make them more difficult to image than others. We explore the potential for scanning electron microscopy (SEM) to improve residue identification in a second test. This test shows a modest improvement in identification success rates of ambiguous residues when SEM images are included. We conclude that while images from different types of microscopes can improve reliability of identification, some residues will always be ambiguous. Rather than being ignored, these ambiguities should be brought to light, closely examined, and published as such.     

Production and subsistence strategies at El Zafrín (Chafarinas Islands,Spain): new data for the early Neolithic of North-West Africa

Until a few years ago North-West Africa was ignored in our hypothesis on the neolithization of Western Mediterranean. Moreover, the few excavations focused exclusively on the test of stratigraphies in order to obtain chronological sequences. Recently developed archaeological projects allowed the inclusion of this region in the scientific debate on the origin and evolution of its Neolithic, on the contacts with the Iberian Peninsula through the Strait of Gibraltar, as well as on the documentation of ways of live, habitation structures, and economic strategies. The open area excavation of Zafrín, in the Chafarinas Isles – an archipelago located a short distance from the North African coast – and the full analysis of its lithic industry (technology, typology and use-wear), here presented, represents a novelty on the Neolithic research in North Africa. This in turn will permit us to approach subsistence strategies and the way of life developed by the Neolithic communities of the region.     

The application of 3D laser scanning technology to the assessment of ordinal and mechanical cortex quantification in lithic analysis

Recent studies make use of cortex proportion as a proxy measurement for the impact of artefact transport on assemblage formation. Cortex in these studies is measured on an ordinal scale and analysed in relation to mechanical measurements of artefact size. Here we report on the use of a 3D laser scanner to obtain precise measurements from experimental lithic reduction sets. High-resolution measurements of cortex area are compared to measurements obtained through ordinal approximations of cortex proportion and mechanical approximations of artefact size. While the ordinal and mechanical measurements result in considerable error for individual artefacts, estimates improve significantly as sample size increases.     

Measuring skill in the production of bifacial pressure flaked points: a multivariate approach using the flip-test

Skill is an aspect of prehistoric technology that can inform us on many areas of investigation. This article discusses the notion of skill in prehistoric contexts and how skill is to be formally defined in relation to lithic bifacial tools. The nature of bifacial manufacture entails simultaneous attention to the facial, profile- and cross- section morphology of the core, since each flake removal affects all features. It is argued that bifacial skill can be measured using a multivariate approach, which takes all these features into account. An index measure, the “Bifacial Skill Score”, is proposed and evaluated using both experimental and archaeological data. This measure is argued to constitute a good proxy for skill in bifacial technology and a useful tool for comparative research.     

The role of abrasives in the formation of lithic use-wear

This paper briefly examines the question of the influence of abrasive particles on the development of use-wear on stone tools. It is argued that grit inclusions may have been a common element of prehistoric tool using conditions, hence the need for archaeological experiments which consider this variable. A series of experiments are described where end-scrapers were used on bone and hide surfaces both with and without a grit inclusion. The resulting wear patterns are discussed and illustrated. It is concluded that the addition of grit to the worked surface causes a dramatic and demonstrable change in use-wear development.     

Lithic Artefacts as a Source of Cultural,Social and Economic Information: the evidence from Aksum,Ethiopia

Extended research covering an area of approximately 300 sq km centered on the ancient metropolis of Aksum has revealed a coherent sequence of development in stone tool production and use spanning most of the last millennium BC and the first millennium AD. It has provided new evidence of the presence of multiple independent lithic traditions in the Pre-Aksumite period, and of Aksumite social and economic organization. This paper summarizes the results of the detailed study of a large corpus of excavated and surface-collected lithics, emphasizing their functional characteristics.

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Résumé  De vastes recherches couvrant sur une superficie d’environ 300 kilomètres carrés et concentrées sur l’ancienne métropole d’Aksoum ont mis à jour une série cohérente de développements dans la production et l’utilisation d’outils de pierre au cours du dernier millénaire avant J.C. et du premier millénaire après J.C. Ces recherches ont fourni de nouvelles informations sur la présence de multiples traditions lithiques indépendantes durant la période pré-aksoumite, et sur l’organisation sociale et économique des Aksoumites. Cet article présente les résultats d’une étude détailée portant sur un large répertoire de vestiges lithiques recueillis au cours de fouilles et collectes de surface, et met en exergue leurs caractéristiques fonctionnelles.

     

The accumulation of stochastic copying errors causes drift in culturally transmitted technologies: Quantifying Clovis evolutionary dynamics

The archaeological record is the empirical record of human cultural evolution. By measuring rates of change in archaeological data through time and space it is possible to estimate both the various evolutionary mechanisms that contribute to the generation of archaeological variation, and the social learning rules involved in the transmission of cultural information. Here we show that the recently proposed accumulated copying error model [Eerkens, J.W., Lipo, C.P., 2005. Cultural transmission, copying errors, and the generation of variation in material culture and the archaeological record. Journal of Anthropology archaeology 24, 316–334.] provides a rich, quantitative framework with which to model the cultural transmission of quantitative data. Using analytical arguments, we find that the accumulated copying error model predicts negative drift in quantitative data due to the proportional nature of compounded copying errors (i.e., neutral mutations), and the multiplicative process of cultural transmission. Further, we find that the theoretically predicted rate of drift in long-lived technologies is remarkably close to the observed reduction of Clovis projectile point size through time and space across North America.