Quantitative micromorphological analyses of cut marks produced by ancient and modern handaxes
Introduction
Cut marks on fossil bones and teeth are an important source of evidence in the reconstruction of prehistoric butchery practices and have a direct bearing on subsistence strategies and the behavioural repertoire of early humans (e.g. Binford, 1981, Blumenschine et al., 1994, Dominguez-Rodrigo and Pickering, 2003, Shipman, 1986). Many such studies have focussed on the interpretation of the microscopic morphology of cut marks (Bartelink et al., 2001, Choi and Driwantoro, 2007, Gilbert and Richards, 2000, Greenfield, 1999, Greenfield, 2004, Greenfield, 2006a, Greenfield, 2006b, Saidel et al., 2006, Shipman, 1981, Villa et al., 1986, Walker, 1978, Walker and Long, 1977, White, 1992), but with rare exceptions (e.g. Walker and Long, 1977, Potts and Shipman, 1981, Shipman, 1983, During and Nilsson, 1991, Bartelink et al., 2001, Kaiser and Katterwe, 2001) these have been qualitative in nature. In recent years, there have been a number of advances in optical microscopy that enable high-resolution three-dimensional images of bone surfaces to be made. Features of the micro-topography of bone surfaces can now be measured that were previously unobtainable using more conventional techniques (e.g. scanning electron microscopy). Recently, this approach was applied to cut marks by Bello and Soligo (2008), who used an Alicona imaging microscope to quantify characters such as cross-sectional shape, depth and shoulder heights. They were also able to infer details of the cutting-edge morphology as well as characteristics such as the inclination of the tool and by inference the tool user's hand during cutting. While experimental work on slicing cut marks (sensu Greenfield, 1999) produced directly on bone has already been reported (Bello and Soligo, 2008), the technique has not been applied to the analyses of slicing cut marks produced during butchery and only preliminary analyses have been undertaken on fossil material (Bello et al., 2007).
In this paper, we demonstrate that this methodology using an Alicona 3D InfiniteFocus imaging microscope can be applied to the study of ancient slicing cut marks on bones from an Acheulean butchery site at Boxgrove, UK. We compared these cut marks to slicing cut marks produced during the experimental butchery of a roe deer using a replica handaxe. Comparisons of cut marks parameters, such as sharpness, depth of cut and inclination, have led to new insights into patterns of carcass-processing and the behaviour of early hominins.
Section snippets
The site
The Boxgrove Acheulean site, near Chichester in southern England, has yielded some of the oldest human remains in northern Europe and one of the richest early Middle Pleistocene artefact and humanly modified bone assemblages yet known (Roberts and Parfitt, 1999). Today, the site is situated 10 km inland of the current shoreline of the English Channel, but during the early Middle Pleistocene it was located on the coast. Subsequent tectonic activity was responsible for raising the marine deposits
Methods
Images of each cut mark were captured using an Alicona 3D InfiniteFocus imaging microscope, using a 5× objective lens at a vertical resolution of 4 μm < z < 5.292 μm and a lateral resolution of 1.75 μm × 1.75 μm. In most cases, the cut marks were scanned in their entirety. In their paper, Bello and Soligo (2008) analysed seven regularly-spaced points along each cut mark, with the first profile at 0.5 mm from the starting point and ending at 0.5 mm from the finishing point of the cut mark (Soligo and Bello,
Results
Results are presented according to the specimen on which analyses were conducted: fossil material (Fossil roe deer, Frd; Fossil large mammals, Flm) and Experimental roe deer (Erd). A distinction has also been made according to the anatomical distribution of the cut marks: long bones (e.g. tibia, fibula), ribs and scapula. Finally, a distinction was made according to the position of cut marks on an anatomical element: either on the midshaft or in proximity to (or on) the articular surface.
Discussion
Alicona images of the fossil and modern cut marks display microscopic criteria consistent with incisions made by a stone tool edge. These features include, internal micro-striations, lateral striations or shoulder effects, Herzian cones and raised ‘shoulders’ along one or both edges (e.g.: Walker and Long, 1977, Eickhoff and Herrmann, 1985, Blumenschine and Selvaggio, 1988, Blumenschine et al., 1996; Fig. 8). Modifications to the method proposed by Bello and Soligo (2008) were necessary because
Conclusions
In this paper, we demonstrate that the analyses of cut mark micromorphology using the Alicona imaging microscope can be applied to the study of ancient and modern butchery slicing cut marks. The methodology proposed by Bello and Soligo (2008) can be equally applied to the study of experimentally produced cut marks and fossil cut marks with only minor modifications. These include profile analyses taken at the mid point of the cut and the use of two new indices (the Angle of the Tool Impact Index
Acknowledgements
This study is a contribution to the Ancient Human Occupation of Britain Project (AHOB). We owe special thanks to the Leverhulme Trust for their financial support of this project. SB also thank the Human Origins Research Fund for additional financial support and Norman MacLeod for encouragement and access to the Alicona 3D InfiniteFocus imaging microscope. We are also grateful to Mark Roberts (Director of the Boxgrove Project) who made the collections available for study and to English Heritage
References (58)
- et al.
The chronology, palaeogeography and archaeological significance of the marine Quaternary record of the West Sussex Coastal Plain, Southern England, UK
Quat. Sci. Rev.
(1997) - et al.
A new method for the quantitative analysis of cutmark micromorphology
J. Archaeol. Sci.
(2008) - et al.
Competition for carcasses and early hominid behavioural ecology: a case study and a conceptual framework
J. Hum. Evol.
(1994) - et al.
An experimental investigation of cut mark production and stone tool attrition
J. Archaeol. Sci.
(2008) - et al.
Shell tool use by early members of Homo erectus in Sangiran, central Java, Indonesia: cut mark evidence
J. Archaeol. Sci.
(2007) - et al.
Relative frequency of butchering cutmarks produced by obsidian and flint: an experimental approach
J. Archaeol. Sci.
(2007) - et al.
Surface marks on bone from a Neolithic collective grave (Odagsen, Lower Saxony): a study on differential diagnosis
J. Hum. Evol.
(1985) The origins of metallurgy: distinguishing stone from metal cut-marks on bones from archaeological sites
J. Archaeol. Sci.
(1999)Analyzing cutmarks: lessons from Artiodactyl remains in the Northwestern United States
J. Archaeol. Sci.
(2005)- et al.
Histomorphometric age assessment of the Boxgrove 1 tibial diaphysis
J. Hum. Evol.
(2001)