The Sheep Project (1): determining skeletal growth,timing of epiphyseal fusion and morphometric variation in unimproved Shetland sheep of known age,sex, castration status and nutrition

The Sheep Project was designed to investigate the effects of castration, breeding age and nutritional plane on bone growth, epiphyseal fusion, tooth eruption and tooth wear in sheep. The project investigates a population of 356 unimproved Shetland sheep skeletons evenly distributed between females bred at different ages, males and castrates, raised on either high or low nutritional planes. This first instalment focuses on two aspects of our larger study, namely bone growth and epiphyseal fusion as affected by sex, castration and nutrition. Nutrition, sex and castration are shown to influence bone growth in ways that are often element-dependant and not consistent through time. We demonstrate that metric variability (variance) is strongest in males, with little difference between females and castrates, and that, in our sample, nutrition has little influence on variance in any sex cohort. Of importance to the development of models of past animal management this study demonstrates that the standard epiphyseal fusion ranges used by zooarchaeologists are too narrow in most instances and do not account for the large variation between sexes or the lesser variation between planes of nutrition. We recommend methods for recognizing castration and the presence of more than one sheep breed, or type, within the zooarchaeological record.     

Age attribution in domestic sheep by skeletal and dental maturation: A pilot study of available sources

The aim of the study was to assess the quality of the available evidence pertaining to the effects of sex and castration on the timing of skeletal and dental maturation in sheep. The initial premise was that our present knowldge of the effects of these factors is inadequate, and that currently available published sources and reference specimens are insufficient to allow confident interpretation of archaeological data. A literature survey was carried out, and adequately documented sheep skeletons in a number of major collections were recorded. The results show that the published evidence is contradictory and ambiguous, particularly with regard to the effects of castration, and that currently available reference material is mostly too diverse in origin and in quality of documentation to allow comparison of well-controlled samples. Some evidence was found to suggest that castration may delay epiphysial fusion during the second year, without delaying fusion of earlier- and later-fusing elements. Overall, it is concluded that much of the received wisdom on skeletal maturation in sheep is poorly founded and unreliable, and that tightly controlled test populations are needed if better data are to be obtained.     

A bone grease processing station at the Mitchell Prehistoric Indian Village: Archaeological evidence for the exploitation of bone fats

Recent excavations at the Mitchell Prehistoric Indian Village, an Initial Middle Missouri site in Mitchell, South Dakota have revealed a large, clay-lined feature filled with fractured and fragmented bison bones. Fracture and fragmentation analysis, along with taphonomic evidence, suggests that the bones preserved within the feature represent evidence of prehistoric bone marrow and bone grease exploitation. Further, the character of the feature suggests that it served as a bone grease processing station. Bone fat exploitation is an activity that is frequently cited as a causal explanation for the nature of many fractured and fragmented bone assemblages in prehistory, and zooarchaeological assemblages have frequently been studied as evidence of bone fat exploitation. The Mitchell example provides some of the first direct, in-situ archaeological evidence of a bone grease processing feature, and this interpretation is sustained by substantial analytical evidence suggesting bone fat exploitation. This new evidence provides a clearer concept of the nature of bone fat exploitation in prehistory as well as an indication of the scale and degree to which bone grease exploitation occurred at the Mitchell site. Finally, this research demonstrates the importance of careful zooarchaeological and taphonomic analysis for the interpretation of both artifactual remains as well as archaeological features.     

Assessing the reliability of criteria used to identify postcranial bones in sheep, Ovis, and goats, Capra

Criteria developed to distinguish between selected postcranial elements of sheep and goats are evaluated using modern specimens from the collections of the Field Museum of Natural History, the National Museum of Natural History, and the Museum of Anthropology and the Museum of Zoology, University of Michigan. Elements considered are: the distal humerus, proximal and distal radius, distal tibia, distal metapodials, astragalus, calcaneus, and the first and second phalanx. This evaluation includes an assessment of 1385 elements from 49 goat and 84 modern sheep skeletons. It also includes a blind test on elements drawn from 20 specimens taken by six analysts with differing levels of experience. Overall, the criteria evaluated are highly reliable, especially in goats and only slightly less so in sheep. A major exception is the distal tibia, where diagnostic criteria tested proved substantially less reliable than other criteria evaluated here. Strongly positive results were also obtained when the sample was partitioned by sex, domestic status, and age. Results of the blind test show some variability depending on the level of experience of the analyst, underscoring the need for training and access to adequate modern reference collections before attempting to apply these criteria to archaeological assemblages. The results of this assessment stand in stark contrast to those obtained in an earlier assessment of the reliability of criteria used to distinguish between mandibles and mandibular teeth of sheep and goats. In all but a few teeth, dental criteria proved to be much less reliable, especially in goats. They were also significantly less reliable in the identification of both younger and older animals. Unlike dental criteria, there are no biases introduced by variable reliability of postcranial criteria that distort taxon-specific harvest profiles based on long-bones.     

An investigation of cortical bone loss and fracture patterns in the neolithic community of Çatalhöyük,Turkey using metacarpal radiogrammetry

Bioarchaeologists have conducted numerous studies on human skeletal remains using metacarpal cortical bone radiogrammetry. This method allows cortical thickness of the second metacarpal to be quantified. As a sensitive index of bone health metacarpal cortical thickness is evaluated in the context of functional adaptations, growth, ageing and bone loss in osteoporosis, as well as used as a reliable indicator of fracture risk. The focus of this study is an examination of the widely used calculation that expresses second metacarpal cortical bone values, followed by an examination of age and sex-related patterns of cortical bone loss and skeletal fragility fracture in a Neolithic archaeological skeletal sample from Çatalhöyük, Turkey. Using metacarpal radiogrammetry, 49 adult metacarpals (f = 27 m = 22) were examined. Data were collected for size variables, length (L) and total bone width (TW) as well as quantity variables, medullary width (MW) and cortical thickness (CT). These parameters were then used to calculate the widely used cortical index (CI) and two new indices expressing medullary width and cortical bone thickness in relation to length (medullary width index, MWI and cortical thickness index, CTI). The ratios were then used to explore age- and sex-related cortical bone loss and fragility fracture patterns amongst the inhabitants of Çatalhöyük. Çatalhöyük males and females demonstrate an inverse relationship where CTI decreases as age and MWI increase. Analyses indicate statistically significant age-related change in MWI amongst the oldest females. Despite age-related loss of bone, no typical fragility fractures are observed. We discuss the role of ageing and lifestyle factors at Çatalhöyük that may have been beneficial to skeletal health and a reduction in the risk of fragility fracture.     

Investigating the potential of micro-focus computed tomography in the study of ancient bone tool function: results from actualistic experiments

Many experiments have sought to recreate the types of damage that would be expected in ancient stone and bone weapon tips. This damage is usually presented as visible fractures or microscopic surface modification. Fatigue tests conducted on bovine bones, however, show the development of internal micro-cracks that result from stress, prior to actual breakage. In this paper I present the results of an experimental investigation of bone points subjected to a variety of activities. I assess the presence of microdamage using micro-focus computed tomography. The results show that two patterns of micro-cracks develop in bone and are best viewed in longitudinal section. Micro-cracks are a cumulative feature dependent on the amount of load applied and the duration of activity. When subjected to high enough loading rates, micro-cracks will merge together to eventually form a fracture. Although further tests are needed to confirm the exact point at which these fatigue fractures begin to form, micro-focus computed tomography has the potential to reveal whether an individual bone point underwent multiple or prolonged impacts and thus to elucidate the probable function/s of ancient pointed bone tools where no visible damage is apparent. Micro-focus computed tomography is a non-destructive and non-invasive procedure and therefore safe to use on archaeological artefacts.     

Diagenesis in bone and enamel apatite carbonate; the potential of density separation to assess the original composition

This paper presents a new approach to the isotopic measurement of diagenetically altered archaeological bone apatite carbonate. We describe how the existing differential dissolution method may be combined with a new approach to remove diagenetically reformed material on the basis of its greater specific gravity. We show that heavier, more diagenetically altered fraction has a higher (altered) δ¹³C and also increased crystallinity within one individual. In addition, we proposed one potential tool to check the validity of bone carbonate by comparing bone collagen, enamel carbonate and bone carbonate values of δ¹³C and radiocarbon content from the same individual. In the case of Danebury cattle, we estimated the biogenic δ¹³C_apa value for DC83 and DC89, although it is still difficult to overcome diagenesis in order to meet the expected value, which is shown to be 1.9‰ (DC83) and 3.5‰ (DC89).     

A new statistical approach for determining the crystallinity of heat-altered bone mineral from FTIR spectra

The crystallinity of bone mineral represents an established method of measuring heat-induced change and is of importance to fields including material science, clinical science, anthropology and archaeology. A commonly used technique involves the calculation of the Crystallinity Index (CI) using selected peaks from Fourier Transform Infrared (FTIR) absorbance spectra. However, the choice of peaks has to date not been statistically justified. In this study a novel application of statistical techniques to the FTIR spectra of bone samples burned in the range 100 °C–1100 °C has been used to identify 5 new spectral indices of heat-induced crystallinity change. The validity of the new indices was tested by using a statistical classification model (LDA) to predict the burning temperature of a set of 108 bone samples burned between 100 °C and 1100 °C. A correct classification rate (CCR) of 97.2% was obtained when a combination of 4 indices including the CI was used. This was significantly better than the CCR of 66.7% which was obtained when the CI was used on its own.     

A distinct region of microarchitectural variation in femoral compact bone: Histomorphology of the endosteal lamellar pocket

Bone is a dynamic tissue, responding locally to differential mechanical loading and systemically to hormonal stimuli. Although the tendency is to consider compact bone a homogenous tissue, regional variations in microarchitecture are known to have quite different properties relating to processes of growth and mechanical loading. Specifically, we investigated an example of microstructural variation of the human, adult femoral endocortex, referred to here as the endosteal lamellar pocket (ELP). The femoral ELP is characterised as a histomorphological meta‐feature, made distinct from general circumferential lamellae by its hemicircumferential lamellar orientation, medial positioning, radially oriented Volkmann's canals and decreased presence of Haversian systems. Our preliminary observations of mid‐diaphyseal transverse thin‐ground sections demonstrate the ELP as a regular meta‐feature of adult human femora unearthed from the Maya archaeological site of Xcambó, Mexico. ELPs were easily identified in 38 of 45 examined individuals. Their size, shape and degree of secondary remodelling were variable. In comparison, ELP lamellae and those originating from the periosteum are divergent, or non‐concentric in orientation. This divergence, along with the ELP's medial position, suggest it forms during growth through endosteal modelling drift. Possible considerations for ELP formation and persistence with age are discussed as well as its implications for the study of bone dynamics during growth and activity. Further research is necessary to quantitatively measure the morphology of ELPs and to identify any co‐variance between ELP characteristics and age, sex or indicators of mechanical loading. Copyright © 2010 John Wiley & Sons, Ltd.     

二十世纪甲骨文语法研究的回顾暨展望

本把一百多年来的甲骨语法研究史分为四个阶段,从研究成果、学术背景、研究领域、研究热点、研究人员、研究材料、研究方法等方面对二十世纪的甲骨语法学研究做了回顾,并对新世纪的甲骨语法研究进行了展望。     

Implications of heat-induced changes in bone on the interpretation of funerary behaviour and practice

Bones submitted to heat experience structural and chromatic modifications. In particular, heat-induced bone warping and thumbnail fractures have been linked to the burning of fleshed and green bones – where the soft tissues have been removed from the bones soon after death – in contrast to dry bones. Those have been suggested as indicators of the state of the individual before being burned thus allowing inferences about the funerary behaviour of archaeological populations. A large sample of 61 skeletons submitted to cremation has been examined for the presence of both of these heat-induced features. Although uncommon, bone warping and thumbnail fractures were present in some of the skeletons demonstrating that its presence is not restricted to the burning of non-dried bones as generally believed. Rather than being an indicator of the presence of bones with soft tissues, bone warping seems to be more of an indicator of the preservation of collagen–apatite links which can be maintained on dry bones with low collagen deterioration. In addition, our results also do not confirm thumbnail fractures as an exclusive sign of the burning of bones with soft tissues. As a result, these heat-induced changes should be used with caution when trying to infer about the pre-burning state of an individual.     

Compensatory bone remodelling in moose: a study of age,sex, and cross‐sectional cortical bone dimensions in moose at Isle Royale National Park

We studied interrelationships among age, sex, and cross‐sectional cortical bone dimensions using quantitative computed tomography (QCT) scans of metatarsal bones of 180 moose (Alces alces) that died in Isle Royale National Park, Michigan. As a large‐bodied quadruped with demanding ecological constraints on movement and behaviour, a moose experiences different weight‐bearing and mechanical stressors than humans, to whom most existing studies of mechanical adaptations of bone pertain. In moose, both sexes showed significant subperiosteal expansion and an increase in medullary area, with an overall increase in cortical bone area over time. Female moose did not exhibit cortical thinning or reduction in cross‐sectional area with age, rather they showed an increase in cortical bone area with periosteal apposition exceeding endosteal resorption, similar to the males. We also found that moose undergo changes in bone geometry through remodelling of bone similar to humans, suggesting a compensatory mechanism for increasing bone strength under conditions of decline in bone mineral density with age. Copyright © 2002 John Wiley & Sons, Ltd.     

The combined use of oxygen isotopes and microwear in sheep teeth to elucidate seasonal management of domestic herds: the case study of Çatalhöyük,central Anatolia

This paper presents and tests a model designed to investigate how off-site herd management developed in settled pre-historic societies. The model is constructed from data collected from traditionally raised local sheep, acting as an interpretive link to published data. The modern comparator was small, but plausible results allow modelling of the archaeological data to be explored. Birth seasonality and herding location are identified through modelled patterns in oxygen isotope data in tooth enamel, and diet just before death by microwear in the same tooth. In combination, these allow aspects of seasonal management of breeding, fallow and slaughter herd sections to be interpreted. Novel practices are discussed in comparison local wild sheep ethology. The case study is Neolithic Çatalhöyük (7400–6200 cal BC) in central Anatolia. Its location provided the opportunity for different parts of the landscape to be used for herding, although choice might have been socially constrained. Data are taken from 72 specimens; the results suggest settlement-wide preference for a suite of practices that kept herds within a day of the settlement and that maintained breeding cycle synchrony with optimal resource availability. Chronological analysis suggests birth season manipulation was tried but rejected, whilst hay or cereal fodder was introduced and became increasingly important. It is argued that herding was probably on dedicated pasture on the arable fringes rather than in closer integration on ‘garden plots’, as there is no evidence of field-edge weed diets and little evidence of adjusting the birth season to accommodate the crop cycle.     

A cautionary note on the use of captive carnivores to model wild predator behavior: a comparison of bone modification patterns on long bones by captive and wild lions

A study with wild lions in Tarangire National Park (Tanzania) and with captive lions in Cabárceno Reserve (Spain) has yielded two different bone modification patterns, probably as a result of the differences in environmental contexts. Captive lions have modified bones more intensively, both in the form of total number of tooth-marked bones and number of tooth marks per tooth-marked bone, probably because of stereotypic behaviors. This emphasizes the importance of environmental contexts to understand carnivore behavior and their resulting bone modification patterns. It also shows that analogical models based on experiments carried out with captive carnivores may be biased and inadequate as proxies for wild carnivore bone modification behaviors.     

云南曹溪寺华严三圣的X光照相检测及初步研究

云南省曹溪寺大雄宝殿内的华严三圣属于木雕造像,是宋代大理国时期的遗物。三尊造像造型庄严肃穆,雕刻精美,是国内宋代造像的代表。为了更好地了解和保护木雕造像,通过X光照相检测,获得了三尊木雕造像的制作工艺、历史修复痕迹和保存状况等信息,这些信息对保护文物具有重要的参考价值。本工作是对大型木雕造像进行X光照相检测的一次有益尝试。     

Variation in strontium isotope ratios of archaeological fauna in the Midwestern United States: a preliminary study

Strontium isotope values (⁸⁷Sr/⁸⁶Sr) in bone and tooth enamel have been used increasingly to identify non-local individuals within prehistoric human populations worldwide. Archaeological research in the Midwestern United States has increasingly highlighted the role of population movement in affecting interregional cultural change. However, the comparatively low level of geologic variation in the Midwestern United States might suggest a corresponding low level of strontium variation, and calls into question the sensitivity of strontium isotopes to identify non-local individuals in this region. Using strontium isotopes of archaeological fauna, we explore the degree of variability in strontium ratios across this region. Our results demonstrate measurable variation in strontium ratios and indicate the potential of strontium analysis for addressing questions of origin and population movement in the Midwestern United States.     

A comparative experiment in the consolidation of cremated bone

This experiment assessed whether consolidation of cremated remains facilitated cross‐sectioning and grinding, which often are required for microstructural analyses such as the histomorphometric estimation of age and the examination of pathological lesions. Green, bovine femoral diaphyses were cremated at three temperature ranges (346–357°C; 610–755°C; 684–838°C) in an electric furnace and then consolidated with Acryloid B‐72 or Butvar B‐98 using simple brushing and immersion techniques. After consolidation was complete, bone pieces were cross‐sectioned and ground to a thickness of 100–120 μm. Results indicate that specimens treated with Acryloid B‐72 are harder and stronger than Butvar treated and untreated control specimens. Acryloid B‐72 is, therefore, recommended for the consolidation of cremated remains in preparation for microstructural analysis. Copyright © 2004 John Wiley & Sons, Ltd.     

Deciphering bone depositional sequences in caves through the study of manganese coatings

The presence of black-coloured bones in caves has been sometimes associated to the use of fire by humans, but more frequently the agent responsible for black colour is the natural deposition of manganese oxides. Manganese coatings were not usually studied once human action was discarded. However, they can provide valuable information about the origin and the sequence of formation of a palaeontological or archaeological deposit. In this paper, we present a quantitative and qualitative study of the manganese coatings that affect most of the bones recovered in the palaeontological site of Liñares cave (NW of Iberian Peninsula) together with other taphonomic marks. The manganese coatings are superimposed on other features previously existing on the surface of the bones. In turn, the coatings can be affected by other agents that modified them totally or partially. The combined interpretation of the different taphonomic marks provides us with valuable information on the sequence where the different taphonomic processes were produced, as for example the intervention of carnivores in the disarticulation of some elements before the burial, the preservation of anatomic connections until after the burial of the carcasses, and the existence of reworking processes in some parts of the infill.     

A pilot study into the effects of X-ray and computed tomography exposure on the amplification of DNA from bone

This research investigates the intersection of radiography and aDNA, two commonly used methods in bioarchaeology. The goal of this project was to investigate the effects of radiation on the ability to amplify DNA from bone. Bones (n = 124) from domestic pig (Sus scrofa) feet were randomly sorted into a control group and four treatment groups: (1) single exposure X-ray; (2) single exposure CT; (3) multiple exposures X-ray; and (4) multiple exposures CT. Number of PCR cycles required to amplify DNA in 100 bp, 200 bp and 400 bp segments were used as a proxy for the amount of available DNA. In the 200 bp CT sample, distal phalanges required significantly more amplification cycles than did the other bones and were removed from analysis. Results suggest that in general radiation exposure fragments DNA thereby decreasing the amount that is amplifiable. While these results are suggestive, further research is required to elucidate the degree to which radiation fragments DNA in archaeological specimens.     

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.