Technology based evolution? A biometric test of the effects of handsize versus tool form on efficiency in an experimental cutting task

The use of stone cutting tools opened a novel adaptive niche for hominins. Hence, it has been hypothesised that biomechanical adaptations evolved to maximise efficiency when using such tools. Here, we test experimentally whether biometric variation influences the efficiency of simple cutting tools (n = 60 participants). Grip strength and handsize were measured in each participant. 30 participants used flint flakes, while the other 30 used small (unhafted) steel blades. Variations in basic parameters of tool form (length, width, thickness, cutting edge length) were recorded for the 30 flint flakes. It was ensured that mean handsize and strength in each participant group were not significantly different to investigate the effect of tool variation. The experimental task required cutting through a 10 mm-diameter hessian rope. Cutting efficiency was measured using both ‘Number of cutting strokes required’ and ‘Total time taken’. Results show that both efficiency measures were significantly correlated with handsize using all 60 participants. However, no significant differences were found between the flake and blade groups in terms of mean efficiency. Nor was any significant relationship found between tool form parameters and efficiency in the flint flake group. We stress that our results do not imply that tool form has no impact on tool efficiency, but rather that – all other things being equal – biometric variation has a statistically significant influence on efficiency variation when using simple cutting tools. These results demonstrate that biomechanical parameters related directly to efficiency of use, may plausibly have been subject to selection in the earliest stone tool-using hominins.     

Reaping ‘rewards’ in sickle use-wear analysis

Recently in their research Goodale et al. (2010) as well as that of Vardi et al. (2010) independently tackled issues of effectively measuring attrition/gloss rates on sickle blade tools from Southwest Asia. Interestingly, while applying new methodology to analyzing sickle tools from different cultural and temporal contexts, these two papers arrived at a similar conclusion: sickle tools were likely very expensive to make, and thus, considerations were made during their production to ensure long use-lives to benefit the people who made and used them in prehistory. Stemp et al. (in this issue) provide a methodological critique of both studies. In addressing their critique we make several points. First it is important to note that Stemp et al. provide no new experimental analysis to justify their assertions, and their critique is ultimately, at best, guesswork. Second, the minimal reanalysis of the data Stemp et al. do conduct arguably lead to the same preliminary conclusion at which we originally arrived: the prehistoric sickle blades we examined were used longer than those we replicated. As stated in our original paper, lithic use-wear studies often do not address issue of reliable and reproducible methods. We believe that our original study helps fill this missing component, and that measuring edge thickness is much less subjective than conventional features on stone tools traditionally identified microscopically. From our perspective, Stemp et al. present largely unsupported critical commentary, lacking substantial reanalysis or experiments to complement or justify their commentary. In the end Stemp et al. provide little more than interesting ideas and conjecture.     

Slicing Cut Marks on Animal Bones: Diagnostics for Identifying Stone Tool Type and Raw Material

Abstract

Butchering implements leave identifying signatures on bones. From these signatures, it is possible to distinguish the different raw materials and types of chipped stone butchering tools. The results of recent experiments enable us to distinguish the different types of raw materials and tools used in the butchering process, in particular those implements that produce slicing cut marks. Three types of chipped stone tools (blades,flakes, and side scrapers) and raw materials (flint, obsidian, and quartzite), as well as issues relevant to lithic production and use were examined and tested. Silicone molds of cut marks produced by each of the instruments were made and subjected to analysis in light optical and scanning electron microscopes under various levels of magnification. The criteria used for distinguishing tool type, raw material, type of production and use characteristics of the respective cutting instruments are presented, as well as a discussion of the application of the experimental results to the Early Bronze Age I site of Afridar, Israel. The data from Afridar indicate that almost all of the butchering marks on animal bones from the site were made by stone tools, in particular haphazardly-made flakes.     

Reaping the rewards: the potential of well designed methodology,a comment on Vardi et al. (Journal of Archaeological Science 37 (2010) 1716–1724) and Goodale et al. (Journal of Archaeological Science 37 (2010) 1192–1201)

The recent articles by Vardi et al., “Tracing sickle blade levels of wear and discard patterns: a new sickle gloss quantification method” (Journal of Archaeological Science 37 (2010) 1716–1724), and Goodale et al., “Sickle blade life-history and the transition to agriculture: an early Neolithic case study from Southwest Asia” (Journal of Archaeological Science 37 (2010) 1192–1201), are two papers that seek to address interesting archaeological questions through the development of new approaches to measuring the duration of stone tool use. Here comment is made on the fashion in which research design and analytic procedures contribute to limit the capabilities of each of the techniques presented. Whilst the authors support the investigation of novel techniques, in order for the results of any use-wear analysis to be accepted as reliable the methods employed must be demonstrably sound.     

An estimator for bidirectional (naviform) blade productivity in the Near Eastern Pre-Pottery Neolithic B

A method is presented for calculating the blade productivity of bidirectional (naviform) blade cores, a hallmark of Near Eastern Pre-Pottery Neolithic B (PPNB) chipped stone tool assemblages. This approach involves estimating the volume of the core that furnished serial blades, together with the mean volume of a typical targeted blade blank. Simple computation of the volume of a wedge in both instances provides an estimate of the number of targeted blades that were produced in an average single reduction sequence. The method is checked against two replicated bidirectional blade reduction sequences, and a refitted bidirectional blade core from the site of Kfar HaHoresh, Israel. Finally, a case study from Kfar HaHoresh is presented in order to illustrate the application of the method, which may have ramifications concerning the evaluation of incipient craft specialization in the region.     

Experiments with Lithic Tools: Understanding Starch Residues from Crop Harvesting

Stone knives were used widely in Neolithic East Asia, presumably in the harvesting of grain crops, but their function has not been clearly understood due to the lack of study of residues from these tools. To address this issue, starch grain analysis was employed to study the residues on the surface of ancient stone knives and large amounts of starches were recovered. The sources of these starches, however, were not well understood, because harvesting of crops involves the cutting of stems rather than direct contact with starchy seeds. To determine whether harvesting could deposit these types of residues, we designed a simulation experiment using stone flakes to harvest ears of wheat, rice and foxtail millet, then analysed the residues on both the flakes and in the plant tissues. A large number of starch grains were found in the stems, including both typical morphotypes from seeds and newly described types that occur only in stems, which can be used as indicators of harvesting. Our study demonstrates that starch grains from residues on the surfaces of archaeological stone knives can indicate not only that the tools were used to harvest ears, but also the type of crops harvested.     

The elemental chemistry of lithic microwear: an experiment

This paper examines the ability of elemental analysis to distinguish microwear traces on stone tools. Our research hypothesised that cleaning procedures of experimental specimens may have heavily influenced previous studies in this area. Experimental flakes are used and cleaned by two alternative methods before laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is applied to study use-wear chemistry. The results show that elementally recognisable traces remain on stone surfaces even with severe cleaning. Also studied were archaeological sickle blades from two sites in Northern England. The results were counter-intuitive demonstrating that experimentally validated models potentially require extensive modification and clarification before being applied to archaeological material. This research identifies methodological problems and errors concerning cleaning within previous experimental studies and highlights new directions for this quantitative analytic approach in microwear analysis.     

Tracing sickle blade levels of wear and discard patterns: a new sickle gloss quantification method

Although sickle blades gloss is known to form during the harvest, which is a dynamic process and although it is known to be a type of wear which is the outcome of the repetitive encounters between the sickle blades working edges and plant stems; there is no common way to quantify its intensity. Since there is no consensus over a specific scale that will enable the estimation of the amount of wear, based on the quantification of gloss brightness intensity. In this paper we propose a new measurement system which is based on the projection of laser (He–Ne) beam on glossed sickle blades and an analysis of the reflected images. The results form a relative scale from which it is possible to infer on the sickle blades level of wear, and to create discard models.     

Insights from a tribological analysis of the tribulum

Since the 1980s, “strange” microwear traces were found to occur on flint blades from sites in the Near East from the late Neolithic and occurring in great abundance by the Early Bronze Age. Although these were considered by archaeologists to be sickles because they had visible gloss on their edges, their use-traces could not be reproduced in harvesting experiments carried out in the field. Subsequently, several lines of evidence were used to study the blades, including not only direct observation of microscopic wear traces, but also Near Eastern cuneiform texts from the third and second millennium BC describing agricultural instruments and analogy with ethnographic and experimental reference material. We found that these tools and their traces best matched traces on flint used to arm the underside of a tribulum (threshing sledge) for threshing grain and cutting straw. We built a replica of the tribulum described in cuneiform texts from the Bronze Age, using copies of the Bronze Age blades, and used this instrument in experiments.     

The oldowan reassessed: A close look at early stone artifacts

Early Stone Age assemblages called “Oldowan” and early “Developed Oldowan” are discussed, based on the results of a long-term study of Plio-Pleistocene sites at Koobi Fora, Kenya and an extensive experimental research program of replicating and using early stone artifact forms. Five major conclusions are drawn from this investigation: (1) many Oldowan core forms (“core-tools”) are probably simple by-products of flake manufacture rather than representations of stylistic norms; (2) flakes and retouched flakes - were essential tools in Oldowan technology, particularly for activities involving cutting; (3) this simple technology does not necessarily reflect the cognitive abilities of the early hominids that manufactured the stone artifacts; (4) there is evidence to show that Oldowan technology can be viewed as a simple curated one, in which raw material was intentionally carried from place to place for future use; (5) early hominid populations that made and used stone implements were not necessarily dependent upon them for their survival.     

NEOLITHIC ‘GREENSTONE’ AXE BLADES FROM NORTHWESTERN ITALY ACROSS EUROPE: A FIRST PETROGRAPHIC COMPARISON*

Neolithic polished stone axe blades, manufactured with uncommon lithologies such as Alpine eclogites, jades and other HP metaophiolites, were exploited from primary and secondary occurrences in Piemonte and Liguria and dominate the north Italian and south‐east French polished stone blades used as functional tools (for deforestation and woodworking). In other European countries the same lithologies are found less frequently or only occasionally as axe blades; in north‐west Europe they were frequently used for manufacturing ceremonial axes that have shapes that are not present in the Italian Neolithic tradition. This paper undertakes a preliminary examination of the case, prevalently from a petrographic point of view, comparing the well‐established Italian petroarchaeometric knowledge with the rather poorer petrographic basis of the European eclogite/jade axes. A provisional picture of the distribution of these axes in Europe is provided and some interim interpretations and open problems are discussed.     

Molluscan Shell Knives and Experimental Cut-Marks on Bones

Abstract

Experimentation demonstrates that the retouched edges of molluscan shells can be used effectively as butchery knives in the absence of lithic raw materials and leave striations on bone surfaces that may be indistinguishable from cut-marks made by stone knives. The potential of such non-lithic cutting tools suggests one new possible category of early artifact, and may explain the presence of cut-marks on fossil bones in paleoenvironments where stone artifacts were absent or rare.     

Reaping bare fields: a response to Stemp et al

In 2010 we have described in JAS a novel method for quantifying sickle gloss. Independently, Goodale et al. (2010) published another method for quantifying gloss based on a different method. Recently, the methods of both teams have been criticized by Stemp et al. We argue below that the critique is lacking and that the method we devised, laser He–Ne measurement, is a way to quantify sickle blade gloss that enables an objective estimate of the intensity of sickles use. The system is not expensive and is time efficient.     

New Excavations at Border Cave,KwaZulu-Natal,South Africa

New excavations at Border Cave use high-resolution techniques, including FT-IR, for sediment samples and thin sections of micromorphology blocks from stratigraphy. These show that sediments have different moisture regimes, both spatially and chronologically. The site preserves desiccated grass bedding in multiple layers and they, along with seeds, rhizomes, and charcoal, provide a profile of palaeo-vegetation through time. A bushveld vegetation community is implied before 100,000 years ago. The density of lithics varies considerably through time, with high frequencies occurring before 100,000 years ago where a putative MSA 1/Pietersburg Industry was recovered. The highest percentage frequencies of blades and blade fragments were found here. In Members 1 BS and 1 WA, called Early Later Stone Age by Beaumont, we recovered large flakes from multifacial cores. Local rhyolite was the most common rock used for making stone tools, but siliceous minerals were popular in the upper members.     

LIME PLASTER AS AN ADHESIVE FOR HAFTING EIGHTEENTH-DYNASTY FLINT SICKLES FROM TELL EL DAB'A,EASTERN NILE DELTA (EGYPT)*

A combination of analytical techniques, including thin-section observations, scanning electron microscopy, X-ray diffraction and X-ray fluorescence analysis, was applied to study the nature and origin of an adhesive used for mounting flint sickle blades to a wooden handle, recovered from early Eighteenth Dynasty culture layers of the multi-layer settlement at Tell el Dab'a, Lower Eygpt. The results obtained from these investigations led to the conclusion that the adhesive is a pure lime plaster, thus providing the oldest evidence for the use of this material as a binding agent so far known in ancient Egypt.     

The Chinese Upper Paleolithic: Geography, Chronology, and Techno-typology

This article reviews the archaeology and chronology of the Chinese Upper Paleolithic and the human fossils attributed to this period. The onset of the Upper Paleolithic in China dates to ca. 35,000–30,000 years ago and is marked by the appearance of a few body decorations and well-shaped bone tools that were added to stone tool assemblages, including core-and-flake tools in North China and cobble tools in South China. The proliferation of blade assemblages in northwest China is interpreted as the cultural impact or the physical presence of bearers of blade industries from western Eurasia. The ensuing appearance of microblade assemblages in North China by 23,000–22,000 years ago reflects the use of local siliceous crystalline nodules by a population that recognized the advantages of this raw material. At that time in South China, prehistoric artisans continued to shape their stone objects from the available flat river cobbles. During the later part of the Chinese Upper Paleolithic (ca. 21,000–10,000 BP), foragers also made bone tools, antler objects, pottery, and shell tools, which laid the technological foundations for the early Neolithic period. One difficulty in this research is that human fossils are rare. Few are well dated and morphological, cultural, and biological interpretations are hotly debated. Our review attempts to facilitate the understanding of a poorly known period in Chinese archaeology and its place in human cultural evolution.     

A late Middle Stone Age artifact assemblage from Sibudu (KwaZulu-Natal): comparisons with the European Middle Paleolithic

It has been suggested that many behavioral innovations, said to appear during the late Middle Stone Age in sub-Saharan Africa, facilitated the expansion of anatomically modern humans from Africa and the Near East into Europe at about 50 kyr; the process eventually led to the replacement of Neanderthals by modern humans and the emergence of the Upper Paleolithic. However, assemblages in this time range are little known in South Africa. In fact, the transition from Middle to the Later Stone Age in Southern Africa is controversial. The early appearance in South Africa of many innovations, such as sophisticated knapping techniques (e.g. the use of soft hammer or indirect percussion in blade production, of composite tools, of microlithic and bladelet technologies) remains to be established through technological analysis.We present here the first results of a project designed to carry out detailed technological studies of several lithic assemblages in South Africa and France dated to the transition period. At this time we have completed the study of a post-Howiesons Poort assemblage from the rock shelter site of Sibudu.The >2 m deep stratigraphic sequence of Sibudu extends from Howiesons Poort at its base to final Middle Stone Age, directly under Iron Age layers. We have analyzed in detail layer RSP (ca. 53 kyr, 1 m above the Howiesons Poort levels) which has provided a large assemblage of several thousand stone artifacts. Compared to published MSA assemblages this industry is unusual for the very high proportions of retouched pieces (15%). The technology is not very elaborate and there is no strong standardization of the end-products. There are no flakes of predetermined shapes; retouch is used to modify irregular flakes to obtain desired edges. Knapping of flakes and blades is done by hard hammer; soft hammer is used only for retouching tools. Interestingly the older Howiesons Poort blades were produced on the same raw materials by soft hammer. Raw material (hornfels and dolerite) was procured from distances of less than 20 km. Unifacial points are the dominant type and there is strong evidence of hafting and use as spear armatures. Detailed comparisons with Middle Paleolithic assemblages of Western Europe show that the late Middle Stone Age technology in South Africa is very similar to that of the Middle Paleolithic; in fact we see no fundamental differences between the two entities, as far as lithic technology is concerned. Implications for the Out of Africa hypothesis are discussed.     

Gloss and use-wear traces on flint sickles and similar phenomena

Using a scanning electron microscope, the high optical polish or gloss and other use-wear traces on the edges of sickle blades are characterized and compared with polishes on other artifacts and natural pieces. The photomicrographs of the surface features and cross sections of the sickle blades as well as laboratory simulation tests, show that the gloss does not form an additive surface layer. Instead, polish formation is considered to be the result of surface alteration caused by frictional mechanisms. Use-wear traces also suggest evidence of how and on what crop the sickles were used.