Experimental archaeology

Classifying polish in use-wear analysis with convolutional neural networks

In this study, we used convolutional neural networks (CNNs) to try and automate the classification of polish traces on stone tools — basically, the shiny or smooth spots that develop on tools from use-wear (e.g., from cutting wood, hide, or bone). We set up experiments with known contact materials (wood, hide, bone) and different use-intensity durations. We also experimented with different imaging parameters (like microscope objective magnification, patch size of image segments) and compared different model architectures (custom CNN vs pre-trained models like ResNet50). We looked into the following questions, * Whether a CNN can reliably tell the difference between polish made by contact with bone, hide or wood. * Whether the duration of use (short term vs long term) affects how easily the model classifies polish * How the imaging setup and model design affect performance (does using a smaller patch of the tool surface versus a larger one matter? Which objective magnification works best? Does a model trained from scratch outperform one that is pre-trained?). We found that CNN approach can classify polish from bone and hide quite well, but struggles more with wood. And also, the models were also able to distinguish polish from short-duration use versus longer use. We also emphasise that to really make this kind of approach robust, the datasets need to be much larger and more varied (different raw materials, contact materials, use contexts) and that imaging/analysis workflows should be optimised. It shows that deep learning has real promise in helping archaeologists analyse use-wear on tools in a more automated, standardised way, which could reduce human bias and increase repeatability. But it also cautions that there are still big challenges, small datasets, limited raw-material/usage variation, and model/generalisation issues mean we’re not yet at the point of “plug-and-play” ML for use-wear. For other researchers (working on archaeological objects, use-wear, materials) this paper suggests that combining controlled experiments + imaging + ML could open new lines of investigation, but we all need to pay attention to dataset design, imaging setup, and model choice.

Exploring early Acheulian technological decision-making: A controlled experimental approach to raw material selection for percussive artifacts in Melka Wakena, Ethiopia

In this paper we looked at how early hominins (tool‐making humans) at the site complex Melka Wakena in the Ethiopian highlands chose different stone materials for making percussive tools (like hammerstones). We gathered stone samples of different rock types found in that area. We measured their physical and engineering properties to see how the raw materials might differ in performance. We found measurable differences in the rock types, harder and denser rocks tended to show less volume loss (for example less damage) under the same experimental stress. For example, one rock (glassy ignimbrite) showed very low visible damage at macroscopic scale compared with others. It gives us concrete evidence that early humans weren’t just randomly picking stones; they may have been making informed decisions about which rocks to use for tools based on their likely durability and suitability for the task. This adds to our understanding of cognitive and technological behaviours in deep prehistory. Also, by establishing a baseline of raw material properties, we can later compare actual archaeological tools and see how performance and raw material choice relate.

The dichotomy of human decision-making, An experimental assessment of stone tool efficiency

In this experiment we tested how different stone raw materials perform as tools—specifically looking at four types, flint, dacite, quartzite and obsidian. We cut into pinewood under identical conditions and measured two key things, how deep the tool edge cuts (effectiveness) and how much the edge wore down (durability). We also measured material‐properties like hardness and grain size to see how those link to performance. What we looked at, Does tool edge efficiency vary with raw material type? (Our null hypothesis was that it doesn’t.) Which materials cut the deepest and also resist wear the best? How do traditional categories of high quality vs low quality raw materials hold up when tested quantitatively under use? We found that the different raw materials behaved very differently, flint showed the highest overall performance (deep cuts and moderate wear). Quartzite, though often considered low quality performed surprisingly well once the initial edge fragmentation settled. Obsidian was brittle and wore fast; dacite had good early performance but then plateaued. Additionally, the classic fine‐grain vs coarse‐grain raw material classification (flint is fine, quartzite is coarse) is too simplistic, some coarse‐grained materials (like quartzite here) can be efficient tool materials under certain conditions. For archaeologists this study gives us experimental data that supports the idea that raw material choice was not random. People in the past likely made technological decisions based on performance of the tool‐materials, not just availability. It also suggests that when you see certain raw materials in the archaeological record, you might infer something about the tasks they were used for, the mobility or procurement strategies of tool‐makers, or even maintenance and resharpening practices.

New and old technologies to understand MP human tool technology, design, and use

NeanderCloud (funded by DFG)

A versatile mechanized setup for controlled experiments in archeology

This paper aims to discuss the contribution of using mechanical apparatus on archaeological experimentation. In this paper, this discussion is illustrated by the presentation of a versatile linear __robot__ used in our experimental workshop at MONREPOS.

Rethinking Use-Wear Analysis and Experimentation as Applied to the Study of Past Hominin Tool Use

In this paper we discuss major topic related to use-wear analysis and, the importance of archaeological experimentation. As needed, we review the state-of-the-art on use-wear methods and experiments and, at the same time, hightlight the need of methodological standards and protocols. One of the most importance aspects discussed in our study is also the holistic perspective that researchers should take when inferring on stone tool use.

Controlled experiments in lithic technology and function

This is an introductory paper to a Special issue based on an organized Symposium at the SAA2017 in Vancouver. The Symposium aimed to bring together researchers working on different aspects of lithic technology and function, which use controlled experimentation to address their questions.

Back to the edge: relative coordinate system for use-wear analysis

Research on stone tool use has shown the importance of sequential experimentation. To evaluate the development of use-wear traces during tool use, the documentation and analysis of the same location on the tools' surface is crucial. In this paper we present a new method based on the implementation of a local coordinate system on experimental sample.

On the origins of human technological innovations, the Late Middle-to-Upper Paleolithic transition in the Levant

Innovations (funded by Leakey foundation)