A new experimental study on percussion marks and notches and their bearing on the interpretation of hammerstone-broken faunal assemblages

Preliminary experiments on bone breakage have shown the potential utility of quantifying some of its diagnostic features (percussion marks, percussion notches) for taphonomic inferences about human and carnivore involvement in bone breakage in faunal assemblages. The present study increases the range of experiments undertaken to understand the identification of hammerstone percussion (dynamic loading) and its differences from carnivore bone breakage through tooth pressure (static loading). This study contributes to a better understanding of frequencies of percussion marks, uncovers and quantifies those percussion marks that lack key diagnostic features to be identifiable and that could be mistaken with carnivore tooth marks, quantifies notch types, shows different size ranges for notches on bones from small and large fauna than previously reported, quantifies the proportion of notches bearing percussion marks, and introduces new size data for percussion (impact) flakes and percussion marks. Furthermore, all these variables have been applied to a dual experimental set: one experiment using non-modified hammerstones and another based on the use of modified hammerstones. Results vary considerably according to hammerstone type. Some of these taphonomic variables increase the range of equifinality when identifying marks and notches created by different human and non-human agents. This calls for further caution when using isolated variables and features rather than a holistic approach to make taphonomic inferences.     

Breaking Bones to Obtain Marrow: A Comparative Study between Percussion by Batting Bone on an Anvil and Hammerstone Percussion

The fat‐ and nutrient‐rich marrow of animal bones can be extracted using different techniques. Passive hammerstone percussion has been the primary focus of experimental bone breaking and the main analogy to understand archaeological bone breakage. Here, the term ‘passive’ is applied because the bone to be broken passively receives the impact from a hammerstone. In addition to this technique, there is another bone‐breaking method that also requires direct percussion, but in an active way. This method is percussion by ‘batting’, in which the bone is actively hit against an anvil until the bone breaks. This technique has rarely been considered at an experimental level and, therefore, has been omitted in the majority of the archaeological interpretations of faunal assemblages with pre‐use of fire technologies. In this study, we attempt to analytically characterize this type of bone‐breaking technique through a systematic comparison with hammerstone percussion. The applied statistical tests will allow us to distinguish some diagnostic modifications, such as the outlines of the fracture planes and the type of notches or their location with respect to the longitudinal axis of the bone. These features and their proportions allow the consideration of the use of this technique in Pleistocene anthropogenic faunal assemblages.     

New analytical methods for comparing bone fracture angles: A controlled study of hammerstone and hyena (Crocuta crocuta) long bone breakage

Accurate interpretation of the cause and timing of bone breakage is essential for understanding the archaeological record. However, many variables potentially influencing break morphology have yet to be systematically explored. Focusing primarily on hammerstone breakage, we introduce new analytical methods for comparing fracture angles using the absolute values of the angle from 90°. We systematically control for intrinsic variables such as taxon, skeletal element, limb portion and skeletal age. We also compare experimental assemblages of femora broken by hammerstone and spotted hyena (Crocuta crocuta). We show that fracture angles are influenced by breakage plane, skeletal element and limb portion. While the latter two have been suggested before, this is the first time the differences have been quantified. We suggest that researchers stratify their assemblages by these variables if they are using fracture angles in analyses. At the assemblage level, hyenas created more oblique fracture angles on oblique breaks than did hammerstones.     

Experimental patterns of hammerstone percussion damage on bones: implications for inferences of carcass processing by humans

The common occurrence of hammerstone percussion damage (pits, striae, notches and impact flakes) on the fossil limb bones of ungulates indicates that marrow extraction has been an important component of hominid butchery for over two million years. Beyond this level of basic inference, it would be behaviorally informative if three deeper aspects of marrow harvesting were understood more clearly: (1) whether inter-element patterns of bone fragmentation vary when processing intensity is held constant; (2) whether butcher investment in marrow extraction correlates positively with the number of percussion marks generated; (3) whether taphonomic effectors can be identified based on percussion mark morphology, frequency and placement. Some experimental work has been conducted previously in service of exploring these questions, but we set out here to address them explicitly through the analysis of a large sample of white-tailed deer (Odocoileus virginianus) limb elements fractured by hammerstone percussion. Our results indicate that (1) measures of bone fragmentation, which supposedly reflect processing intensity, are highly contingent on the research question being posed. This stresses the fact that researchers must be explicit in their definition of processing intensity. (2) In addition, hypothesized covariance between number of hammerstone blows and percussion mark frequencies are not met in our sample, corroborating previous conclusions of a lack of covariance between cutting strokes and cutmark frequencies. These results highlight the contingent nature of butchery mark production, and emphasize the need to investigate carcass resource exploitation by posing questions that do not rely on mark frequencies, but instead utilize other zooarchaeological measures. (3) Finally, our results—showing high incidences of impact notches and flakes created by direct anvil contact and “anvil scratches” created by direct hammerstone contact—suggest caution in using specific categories of percussion damage to infer their taphonomic effectors.     

A taphonomic study of bone modification and of tooth‐mark patterns on long limb bone portions by suids

This work presents new taphonomic data on bone modification by suids, including domestic pig, wild and hybrid boars. The intense modification undergone by bones from animals smaller than 100 kg is shown, together with a more moderate modification on bones from larger animals. Both the ravaging pattern (with preferential deletion of cancellous tissue) and the tooth‐marking frequencies are similar to those documented among hyenas and dogs when having primary access to complete bones. A dual‐patterned experimental model consisting of the interaction of humans and suids was also considered. Here it is shown how suid modification of hammerstone‐broken bone assemblages is different from that documented among canids and hyaenids, as experimentally replicated. These results increase the number of non‐anthropogenic bone‐modifying agents and posit new issues on equifinality processes. Copyright © 2008 John Wiley & Sons, Ltd.     

Túnel: A Case Study of Avian Zooarchaeology and Taphonomy

Although not often considered, there are many osteological characters unique to the avian skeleton that influence the taphonomy of bird bones. These characters are reviewed and their archaeological significance discussed herein. The presence of marrow in many avian long bones is important to interpretation of avian remains from archaeological sites because the presence of marrow affects bone density and, in turn, preservation. Other structural properties that affect avian bone preservation include cortical wall thickness, length and pneumatic state. Based on an analysis of approximately 10,000 bird bones from the archaeological site of Túnel, Tierra del Fuego, Argentina, I found that specific breakage patterns resulted from natural taphonomic processes acting as a result of the unique avian bone characteristics. This information may allow researchers to distinguish breakage patterns in avian bones resulting from natural taphonomic processes from breakage patterns that are culturally induced.     

Reconsideration of criteria for differentiating faunal assemblages accumulated by hyenas and hominids

Zooarchaeologists have established several criteria for differentiating hominid‐ and hyena‐derived faunal assemblages. In some cases, however, the patterns of skeletal part representation and bone surface modification on which these criteria are ultimately based have been observed in fossil bone assemblages of unknown origin, rather than in modern assemblages of known origin. When the proposed criteria are evaluated within an actualistic framework, only three are able to differentiate between hominid‐ and hyena‐created faunal assemblages. I suggest that only these three criteria—proportions of carnivores to ungulates in the assemblage, the preserved condition of long bone specimens (either as whole cylinders or as splintered shaft fragments), and the types of bone surface modifications—should be retained as important factors in a diagnosis of the ancient bone‐collector. The remaining four criteria—the relative proportion of horn pieces in the assemblage, the relative representation of podial bones, the relative representation of small and large bovid skeletal parts, and bovid mortality profiles—are not relevant or applicable to the problem of differentiating hominid‐ from hyena‐derived faunal assemblages. Copyright © 2002 John Wiley & Sons, Ltd.     

Bone surface modifications in zooarchaeology

Cutmarks made by stone tools, conchoidal flake scars from hammerstone percussion, carnivore tooth marks, striations from sedimentary abrasion, and other surface modifications on bones from archaeological sites constitute a crucial body of evidence for investigating the role of human behaviors and of nonhuman taphonomic processes in site formation. This paper describes the various kinds of bone surface modifications produced by humans and by nonhuman processes and assesses the current status of bone surface modification studies with regard to such issues as the need for greater analytical standardization, the selection of instruments for examining bone specimens, tactics for identifying the origins of marks on bones, and strategies for inferring human behaviors.     

Actualistic research into dynamic impact and its implications for understanding differential bone fragmentation and survivorship

The relationship between bone mineral density and archaeological bone survivorship has played a critical role in zooarchaeological and taphonomic studies in recent decades. Numerous studies have suggested that higher-density skeletal element portions survive more frequently than lower-density element portions when archaeological assemblages are affected by some taphonomic processes. Interpretations of density mediated destruction have become commonplace in the archaeological literature, and are often used to explain the absence of certain bone elements and element parts in zooarchaeological assemblages. This study explores the effects of rockfall on bovid elements in varied environmental conditions and the differential survivorship of their element parts, and has implications for understanding the taphonomic processes through which bones are subjected to dynamic loading. Actualistic rockfall experiments conducted on twelve samples of frozen, fresh, and semi-dried bovid bones reveal that the generally low-density epiphyseal ends of bone elements resist fracture and analytical deletion with more frequency than the higher-density diaphyses. This evidence suggests that bone density does not correlate with likelihood of breakage or effective archaeological “destruction” when rockfall and other processes that result in dynamic impact are in action. While this research does not question the relationship between bone mineral density and the likelihood for archaeological survivorship as the result of some taphonomic processes, it presents one specific set of taphonomic processes that result in the differential survivorship of low density bone elements parts and the fragmentation and destruction of higher density element parts. This research presents evidence that shows that dynamic impact is a process capable of fragmenting and sometimes destroying high-density elements while low-density elements survive.     

Fluvial transport of bovid long bones fragmented by the feeding activities of hominins and carnivores

This study explores the hydraulic transportability of bovid long bone fragments created through hominin and carnivore carcass consumption in order to determine the effect of fluvial transport on the incidences of hominin- and carnivore-induced bone surface modifications. Transportability was determined using an oval race track flume and 311 long bone fragments from modern control collections of hominin- and carnivore-modified bone. Results show that the fluvial transport of long bone fragments is predicted by animal size class and bone specimen size, as measured by maximum cortical thickness, maximum length, and maximum width. All of these variables can be measured on fossil specimens. Long bone portion (midshaft, near-epiphysis, and epiphysis) does not affect transport and hydraulic transport does not substantially modify the incidences of tooth, percussion, and cut marking in transported or lag assemblages in low energy fluvial environments. Implications of this study are: 1) animal size classes, and cortical thickness, length, and width of long bone fragments can be used to identify fluvial winnowing in fossil assemblages; 2) analyses concerning the relative timing of hominin and carnivore carcass consumption based on the proportions of long bone fragments bearing tooth, percussion, or cut marks can be meaningfully applied to fossil assemblages deposited in low-energy fluvial environments.     

Comparing Levels of Subsistence Stress amongst Norse Settlers in Iceland and Greenland using Levels of Bone Fat Exploitation as an Indicator

Abstract

The background to the Icelandic and Greenlandic sites under investigation is outlined and prior work on the Norse economies of the two islands is discussed. The importance of fat in the diet and the use of levels of bone marrow and grease exploitation as an indicator of subsistence stress are explained. The methodology for establishing levels of bone fat exploitation is outlined. This methodology involves the detailed study of fragmentation levels of different types of bone, study of bone fracture types and many other taphonomic indicators. The results of the study are described and discussed. On Greenland, the Norse inhabitants exploited almost all available fat from land mammal bones, leaving only the ribs. It is argued that this indicates a severe level of subsistence stress amongst the Greenlanders that is most likely related to a seasonal dearth in resources. On Iceland, whilst a certain amount of bone marrow is almost certainly exploited, the settlers appear to almost totally ignore the potential to exploit bone grease. This is likely to be indicative of a much more healthy subsistence economy than on Greenland. These results are discussed in relation to differing climate, availability of good soil, fishing practices and seasonal rounds.     

Skates and Prickers from the Circular Fortress of Oost-Souburg,The Netherlands (AD 900–975)

Abstract

During the excavation of the circular fortress of Oost-Souburg, the Netherlands, objects of bone and antler were found: combs, needles, spindles, three-pronged objects, bone skates and points. The finds are dated between AD 900 and 975. In this contribution the objects which belong to the winter season, the bone skates and the points, are discussed. The skates occur in various types and are made of a variety of bones. Certain types of skate were used without bindings, others were either designed to be fastened to the feet or possibly were tied only at the heels. The roughly-made points that were found may be the points of the prickers used to propel the skater forward on his skates.     

An experimental study of large mammal bone modification by crocodiles and its bearing on the interpretation of crocodile predation at FLK Zinj and FLK NN3

The taphonomic signature of crocodiles as agents of bone modification has been previously identified by specific tooth mark types (e.g., bisected pits) and by a conspicuous presence of these marks: more than 75% of bones modified by crocodiles bear at least one of these distinctive marks. Therefore, crocodile tooth-marking would be notably prevalent in bone assemblages resulting from crocodile predation and active scavenging. The present study contributes to refine this diagnosis by showing greater variability of these types of marks, a different degree of tooth-marking intensity, and a somewhat different distribution of tooth-marked elements according to skeletal parts from previous experiments with crocodiles. Some of these differences are due to different experimental variables and conditions and this highlights the need to understand behavioral variability in crocodile ecological settings. This variability in crocodile tooth-marking probably results from several as-yet-inadequately measured behavioral and ecological factors, such as intensity of feeding competition and differences between male and female crocodile feeding behaviors, among others. Furthermore, this study also contributes to a better definition of the microscopic criteria that can be used to distinguish crocodile-inflicted marks from other types of bone surface modifications. In light of these and previous experimental frameworks, we reevaluate the application of these analogs to modifications documented in hominin fossils from Olduvai Gorge (OH8 and OH35) and the resulting inferences about the hazard posed by crocodiles on the paleolandscape where FLK North North and FLK Zinj (Bed I) were formed. The taphonomic analysis also shows that Olduvai OH8 and OH35 were probably not preyed upon by crocodiles. It is concluded that no tangible evidence can be used to support the interpretation that OH35 was modified by crocodiles and that the overall presence of crocodiles in FLK North North and FLK Zinj was rather marginal, based on the virtual absence of crocodile-modified bones in both archaeofaunal assemblages.     

The Red Fox (Vulpes vulpes) as an Accumulator of Bones in Cave‐like Environments

Identifying the behavioural patterns of bone collecting animals is a crucial aspect of taphonomic studies. Although many studies have established criteria for identifying animal‐collected or animal‐modified bones, very few papers describe the distinguishing features of fox‐made bone assemblages. The bone assemblage collected in an inactive underground stone mine in Potok‐Senderki (Poland) is diagnostic of a red fox (Vulpes vulpes) den. This site provides an ideal opportunity to develop an understanding of the bone collecting behaviour of red foxes in cave‐like environments. This study showed that bones collected by red foxes are concentrated in clusters. The bones represent a broad spectrum of local fox prey species, with most bones showing the marks of gnawing. Each cluster may contain from <10 to >100 bones. Furthermore, the long axes of the bones in clusters frequently show specific orientation. The analysis of bones at this site might make an important contribution towards the establishment of baseline criteria for the identification and evaluation of fox‐accumulated bone assemblages. Copyright © 2012 John Wiley & Sons, Ltd.     

Baboon Bone Mineral Densities: Implications for the Taphonomy of Primate Skeletons in South African Cave Sites

C. K. Brain (e.g., 1981) documented an interesting difference in relative skeletal part representation between primates and bovids of similar live body size recovered from the fossil cave site of Swartkrans (South Africa). Hominids and baboons are represented primarily by skull parts and a paucity of postcranial bones, while small sized bovids (Size Classes 1 & 2) are represented by more equivalent abundances of all skeletal elements. Brain argued that the Swartkrans bones were primarily carnivore collected, and postulated that the difference in element frequencies between primates and bovids is the manifestation of less durable primate postcranial skeletons relative to those of bovids when either are subjected to a destructive process such as carnivore feeding. Experiments by Brain (1981) in which baboon and bovid carcasses were fed to large, African carnivores lend support to this hypothesis. Bovid postcranial elements survived carnivore feeding more frequently and more completely than those of primates. Assuming that bulk bone mineral density (bulk BMD) is a measure of durability, we supplement Brain's observational data by presenting the first systematic, element-by-element comparison of baboon and bovid postcranial bulk BMD measurements obtained by dual energy X-ray absorptiometry (DXA). While the bovid in our sample exhibits greater absolute bulk BMD values in 57·8% of all measured bone areas, when grouping areas by body region, a statistically significant difference in absolute bulk BMD values between the baboons and bovids is documented only in the hindlimb region (i.e., femur, tibia and patella). Density differences in other body regions are not statistically significant. Further, in only one case (i.e., small bovids in the Member 2 [1948–1953/1965–1975 excavation] assemblage) is there a significant and positive correlation between skeletal part frequencies of primates or bovids and bulk BMD. This suggests that, for the most part, primate and bovid skeletal part representation at Swartkrans is not the result of density-mediated processes. Differences in skeletal part representation between primates and bovids at Swartkrans may thus be attributable to factors other than bone density—such as bone size, length, shape, and/or the relative palatability of surrounding soft tissues on bones.     

Examining criteria for identifying and differentiating fossil faunal assemblages accumulated by hyenas and hominins using extant hyenid accumulations

Numerous authors have put forth criteria for distinguishing between assemblages collected by hyenas and hominins. Of the seven most recognised criteria used to distinguish hyenid from hominin assemblages, it has recently been suggested that four be rejected and three retained. The four rejected criteria are: an excessive proportion of horns and horn cores in hyena accumulated assemblages; the absence of small, hard, compact bones; mortality profiles; and the ratio of cranial bones to postcranial bones. The three criteria previous researchers suggested be retained are: a carnivore MNI ratio of ≥20%; an abundance of cylinder fragments; and hyena‐inflicted damage upon the bones. In this examination of over 27,000 faunal remains associated with all three species of extant bone‐collecting hyenids from four countries and two continents, six of the seven previously established criteria and reconsiderations of criteria have been evaluated. The results of the present study indicate that of the six criteria examined, none, as written, are indicative of hyenid activity on bone assemblages of unknown origin. Copyright © 2008 John Wiley & Sons, Ltd.     

TESTING AN ALTERNATIVE HIGH‐THROUGHPUT TOOL FOR INVESTIGATING BONE DIAGENESIS: FTIR IN ATTENUATED TOTAL REFLECTION (ATR) MODE*

Archaeological bone undergoes alterations after burial (diagenesis) that constitute a problem for the survival of archaeological information. A common method to assess this alteration is Fourier transform infrared spectrometry (FTIR). However, the commonly applied method (FTIR–KBr) is destructive and sample preparation may influence the results. This paper tests the suitability of FTIR attenuated total reflection (FTIR–ATR), a method not commonly used to investigate bone diagenesis. FTIR–ATR requires less sample preparation and can be non‐destructive, allowing analysis of bone cross‐sections. Modern and archaeological bones were analysed using both methods and different sample preparation methods were tested. The results show that FTIR–ATR has advantages for the rapid assessment of bone diagenesis.     

Bone Diagenesis and Taphonomic History of the Paso Otero 1 Bone Bed, Pampas of Argentina

Samples of guanaco bone from an archaeological site in the Pampas of Argentina have been analysed to understand the diagenetic profile of the bone assemblages that characterized the taphonomic history of the site. Two archaeological occupations of Paso Otero 1 were investigated, encompassing similar landscape settings, climates, and depositional environments. The time span is a c. 2000 year period from c. 4800 to 2800 years . A total of 30 bone samples taken from both occupations were used to provide a preliminary characterization of the diagenetic pathways at the site. The parameters investigated provide a comprehensive account of how both mineral (hydroxyapatite) and bone protein (collagen) have been altered. In order to compare the two bone assemblages in terms of their diagenetic parameters, multivariate analyses were conducted. Results indicate two different diagenetic profiles in the site, % N being one of the variables that accounts for most of the variation in Paso Otero 1. The diagenetic analyses indicate that protein is less preserved in the bone assemblage from the middle stable landscape. Alternative interpretations of the diagenetic profiles are discussed in light of the taphonomic history of the site, and palaeoenvironmental information of the region. One hypothesis stresses the importance of the role of climate in defining the different diagenetic pathways, and the other the continued action of the combined diagenetic factors along time as the main explanation for the variability in the state of preservation of the bones in Paso Otero 1.     

Well preserved non‐collagenous extracellular matrix proteins in ancient human bone and teeth

Ancient bones in a good preservation state, ascertained by microscopic techniques, conserve extracellular matrix proteins over thousands of years. With new techniques, intact extracellular matrix proteins from ancient bones and teeth are extracted and separated by one‐dimensional and two‐dimensional electrophoresis. Proteins were identified in Western blots by special antibodies against different human extracellular matrix (ECM) molecules of bone. We have confirmed different types of ECM human bone molecules such as osteonectin, osteopontin, and alkaline phosphatase with specific antibodies in human bone samples from different age groups. Additionally, we selected bone samples from different cultural time periods, such as the Middle Ages, the Bronze Age and the Late Pre‐Pottery Neolithic Phase (PPNB), and teeth from individuals from the Early Middle Ages and from the Late PPNB. The survival of intact extracellular matrix proteins in ancient bones and teeth dating from recent times to the Late PPNB, and reliable techniques to identify these proteins, present a great challenge to further research. A Match Set with PD‐Quest 7.2 shows that only 16% of protein spots in the teeth are also found in the bone of the same individual. In combination with the results of macro‐ and microscopic investigation, biochemical techniques will help us in obtaining a better understanding of bone and teeth in health and disease. Copyright © 2006 John Wiley & Sons, Ltd.