Visual Attention and Cognitive Archaeology: An Eye-Tracking Study of Palaeolithic Stone Tools

The study of lithic technology can provide information on human cultural evolution. This article aims to analyse visual behaviour associated with the exploration of ancient stone artefacts and how this relates to perceptual mechanisms in humans. In Experiment 1, we used eye tracking to record patterns of eye fixations while participants viewed images of stone tools, including examples of worked pebbles and handaxes. The results showed that the focus of gaze was directed more towards the upper regions of worked pebbles and on the basal areas for handaxes. Knapped surfaces also attracted more fixation than natural cortex for both tool types. Fixation distribution was different to that predicted by models that calculate visual salience. Experiment 2 was an online study using a mouse-click attention tracking technique and included images of unworked pebbles and ‘mixed’ images combining the handaxe's outline with the pebble's unworked texture. The pattern of clicks corresponded to that revealed using eye tracking and there were differences between tools and other images. Overall, the findings suggest that visual exploration is directed towards functional aspects of tools. Studies of visual attention and exploration can supply useful information to inform understanding of human cognitive evolution and tool use.

New Caledonian crows keep ‘valuable’ hooked tools safer than basic non-hooked tools

The temporary storage and re-use of tools can significantly enhance foraging efficiency. New Caledonian crows in one of our study populations use two types of stick tools – hooked and non-hooked – which differ in raw material, manufacture costs, and foraging performance. Using a large sample of wild-caught, temporarily captive New Caledonian crows, we investigated experimentally whether individuals prefer one tool type over the other when given a choice and whether they take better care of their preferred tools between successive episodes of use, safely storing them underfoot or in nearby holes. Crows strongly preferred hooked stick tools made from Desmanthus virgatus stems over non-hooked stick tools. Importantly, this preference was also reflected in subsequent tool-handling behaviour, with subjects keeping hooked stick tools safe more often than non-hooked stick tools sourced from leaf litter. These results suggest that crows ‘value’ hooked stick tools, which are both costlier to procure and more efficient to use, more than non-hooked stick tools. Results from a series of control treatments suggested that crows altered their tool ‘safekeeping’ behaviour in response to a combination of factors, including tool type and raw material. To our knowledge, our study is the first to use safekeeping behaviour as a proxy for assessing how non-human animals value different tool types, establishing a novel paradigm for productive cross-taxonomic comparisons.

Mammoth Ivory Rods in Eastern Beringia: Earliest in North America

The Holzman archaeological site, located along Shaw Creek in interior Alaska, contained two mammoth ivory rods, of which one is bi-beveled, within a stratigraphically sealed cultural context. Dated 13,600–13,300 cal BP, these are the earliest known examples of osseous rod technology in the Americas. Beveled ivory, antler, and bone rods and points share technological similarities between Upper Paleolithic Europe, Asia, eastern Beringia, and the Clovis tradition of North America and are important tool types in understanding the late Pleistocene dispersal of modern humans. The Holzman finds are comparable to well-known Clovis tradition artifacts from Anzick (Montana), Blackwater Draw (New Mexico), East Wenatchee (Washington), and Sherman Cave (Ohio). We describe these tools in the broader context of late Pleistocene osseous technology with implications for acquisition and use of mammoth ivory in eastern Beringia and beyond.

Why invent the handle? Electromyography (EMG) and efficiency of use data investigating the prehistoric origin and selection of hafted stone knives

For over 3 million years hominins held stone-cutting tools in the hand, gripping the portion of tool displaying a sharp cutting edge directly. During the late Middle Pleistocene human populations started to produce hafted composite knives, where the stone element displaying a sharp cutting edge was secured in a handle. Prevailing archaeological literature suggests that handles convey benefits to tool users by increasing cutting performance and reducing musculoskeletal stresses, yet to date these hypotheses remain largely untested. Here, we compare the cutting performance of hafted knives, ‘basic’ flake tools, and large bifacial tools during two standardized cutting tasks. Going further, we examine the comparative ergonomics of each tool type through electromyographic (EMG) analysis of nine upper limb muscles. Results suggest that knives (1) recruit muscles responsible for digit flexion (i.e. gripping) and in-hand manipulation relatively less than alternative stone tool types and (2) may convey functional performance benefits relative to unhafted stone tool alternatives when considered as a generalised cutting tool. Furthermore, our data indicate that knives facilitate greater muscle activity in the upper arm and forearm, potentially resulting in the application of greater cutting forces during tool use. Compared to unhafted prehistoric alternatives, hafted stone knives demonstrate increased ergonomic properties and some functional performance benefits. These factors would likely have contributed to the invention and widespread adoption of hafted stone knives during the late Middle Pleistocene.

COMPARISON OF METHODS FOR CONTROLLED THERMAL DEFORMATIONS IN MACHINE TOOLS

Progress in improving the accuracy of metal-cutting machines is inextricably linked and driven by deeper knowledge gained through the study of thermal processes and effects occurring in machines, which can be used to manage them. This led to the dominance of temperature errors in the balance of machine accuracy, the share of which changed from 20-30% to 70% during the period from 1950 to 2020, which is determined by the absolute value of the achievable machine accuracy. Types and forms of compensation methods were formed (1990-2020), which were based on the use of linear and nonlinear regression or correlation methods. Performing experiments can establish the functional relationship between the measured temperature in the machine nodes and the amount of displacement. With good repeatability and stable reproducibility of the result, an equation expresses this functional relationship. Applying this equation to a program, a control device compensates the thermal deformations. However, in all cases, it is necessary to determine the number and location of temperature measurements on the machine, determining the compensation accuracy. The proposed sensorless model is based on a thermal behavior model and does not require temperature measurements. A method is presented and justified for estimating the number of temperature measurement locations based on thermophysical analysis by applying the finite element method in comparison with the analytical method in order to achieve the required compensation accuracy. For several machine tool types, a comparison is given regarding the control method of the TCP spindle displacement without sensors and with temperature sensors. The limits of their rational use are presented.

The Middle Paleolithic Ground Stones Tools of Nesher Ramla Unit V (Southern Levant): A multi-scale use-wear approach for assessing the assemblage functional variability

In the archaeological record, Ground Stone Tools (hereafter GST) represent an important tool group that provides invaluable data for exploring technological development and changes in resource exploitation over time. Despite its importance, Lower and Middle Paleolithic (MP) GST technology remains poorly known and understudied. The MP record of the Levant constitutes a compelling case study for exploring the nature and character of GST technology. Especially the site of Nesher Ramla (Israel, end of Marine Isotope Stage 6/beginning of 5) has provided one of the world’s largest GST assemblages from MP contexts. Aiming at evaluating the variability of tool types at the site from a technological and functional perspective, this study follows an analytical approach which integrates different scales of analysis. Our workflow seeks to generate and combine qualitative and quantitative data allowing: 1) the identification of damage areas, and 2) functional analysis, based on the location, distribution, and characterization of use-wear traces. This study shows a substantial level of diversification in resource exploitation (e.g., mineral, hard animal material and likely perishable components). Results show the presence of several tool types on which diagnostic use-wear can be associated with different activities. Importantly, our analysis indicates the presence of various hammerstone types showing distinct wear characteristics. The variability observed within the hammerstones likely reflects different functions, including in some cases the processing of distinct worked materials. Ultimately, this study contributes to our understanding of the significance of GST technology for the ecological dynamics of MP populations.

Production Sites on the Beach Ridge of Järavallen: Aspects on Tool Preforms, Action, Technology, Ritual and the Continuity of Place

Järavallen is the name of a beach ridge along the south and south-west coasts of Scania in the southern part of Sweden. Large amounts of flinttool preforms, particularly for square-sectioned Neolithic axes, have been found on three sites along this beach ridge. The several thousand preforms represent tool types from the Early Neolithic to the Early Bronze Age. The three sites have not been given much attention in recent archaeological research. With a basis in a discussion of action, technology, ritual and the continuity of place, these three sites are analysed and interpreted as representing traditions involving repeated actions over a long period of time. The production and deposition of the preforms are seen as an investment for the future.

Bone and antler artefacts from the Middle and Late Mesolithic layers of Ivanovskoye 7 in the collection of MAE RAS

A collection of bone artefacts from Mesolithic layers of the site Ivanovskoye 7, excavated by the Upper Volga expedition under direction of M.G. Zhilin was taken for permanent storage by MAE RAS in 2012. Three cultural layers yielded impressive collections of bone and antler artefacts of early, middle and late periods of the Butovo culture. Finds from the bottom layer are already described in detail [Zhilin 2018]. The present article is devoted to publication of bone and antler artefacts from the Middle and Late Mesolithic layers of this site. Further development of traditions of the bone industry of the bottom layer is observed in these layers. At the same time new tool types emerge, and some types of bone and antler artefacts widespread in the bottom layer are absent in the upper layers. Comparison of finds from Mesolithic layers of Ivanovskoye 7 with other peat bog sites of the Butovo culture indicates rather steady development of bone industry. During the whole period of its existence the population of the Butovo culture was equipped with a highly developed set of bone and antler artefacts needed for successful living in the forests of temperate zone. Bone industry of the Late Mesolithic layer of Ivanovskoye 7 found further development in the Early Neolithic Upper Volga culture.

Using mechanical experiments to study Ground Stone Tool use: exploring the formation of percussive and grinding wear traces on limestone tools

Ground Stone Tools (GST) have been identified in several Levantine archaeological sites dating to the Middle Paleolithic. These tools, frequently made of limestone, are often interpreted based on their morphology and damage as having been used for knapping flint, and sometimes for breaking animal bones or processing vegetal materials as well. However, the lack of experimental referential collections on limestone is a major obstacle for the identification of diagnostic traces on these types of tools and raw material. In this sense, the understanding of the specific function of these GST and the association between tool types and activity often remains unknown or merely speculative.Recent discoveries at the site of Nesher Ramla revealed one of the largest Middle Paleolithic assemblages of limestone GST. Our use-wear analysis has identified several types of both macro and micro-wear traces on different tools. Such diversity highlights the need for developing an experimental reference collection that can enable detailed comparison between experimental and archaeological use-wear evidence.In this paper, we present the results of mechanical experiments specially designed to understand and quantify major characteristics of macro and micro use-wear traces on limestone GST as a result of three main activities: 1) animal bone breaking, 2) flint knapping and 3) grinding acorns. This study pursues three main goals: a) improving our ability to distinguish natural from anthropogenic alterations on limestone; b) identifying and characterizing differences between wear-traces (macro and micro) produced by different activities, and c) building a reference collection for thorough comparisons of use-wear and residues on archaeological tools.Our results indicate that it is possible not only to identify anthropogenic alterations but also to specifically distinguish the use-wear traces formed on limestone as result of percussive activities of bone and flint. This is shown by controlled experiments allowing variables other than the worked material to remain constant. This study aims to contribute towards establishing an experimental and multi-scale library of use-wear traces on limestone.