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.     

Prediction Models for Age‐at‐Death Estimates for Calves,Using Unfused Epiphyses and Diaphyses

For cattle (Bos taurus), age estimations using dental criteria before the eruption of the first molar (3–8 months) have large error margins. This hampers archaeozoological investigation into perinatal mortality or the putative slaughtering of very young calves for milk exploitation. Previous ageing methods for subjuveniles have focused on the length of unfused bones, but it is rarely possible to use them because they are restricted to foetuses and because of the fragmentation of bones. This paper presents new age prediction models based on length, breadth and depth of post cranial bones produced from a dataset of modern calves (n = 27). This reference collection was compiled from material of known age at death, sex and breed from collections in Britain, France, Germany and Switzerland. Linear regression models were constructed using the modern data for age prediction, and these models were then successfully tested and assessed using a Middle Neolithic assemblage of complete calves' skeletons from Bourguignon‐Lès‐Morey, France. From the assessment, the astragalus and metapodials were determined to be the most reliable bones, and the femur was the worst. Measurements of the epiphyseal and distal elements and depth measurements were the most reliable. For ages before 12 months, these models can provide ±1 month age estimates. Copyright © 2013 John Wiley & Sons, Ltd.     

Tending and drive hunting: A density-mediated attrition model can explain age profiles of white-tailed deer at Iroquoian village sites

In a 1993 paper, Noble and Crerar suggested, based on the age and sex distribution of white-tailed deer (Odocoileus virginianus) longbones from four Attawandaron Iroquoian sites around the western end of Lake Ontario, that the contact-period Attawandaron were managing local deer populations, in response to the aboriginal trade in hides. Having observed similar patterns of differential preservation of elements and epiphyseal fusion at nearby Iroquoian sites that are not ascribed to the Attawandaron, and which pre-date the hypothesised trading period, we argue that these patterns may instead relate to bone density and/or vulnerability to taphonomic effects of late-fusing epiphyses. We further support our argument through age profiles based on dental eruption and wear.     

A Metrical Analysis of a Collection of Modern Goats (Capra hircus aegargus and C. h. hircus) from Iran and Iraq: Implications for the Study of Caprine Domestication

A critical comparison of two commonly used markers of initial animal domestication, size reduction and demographic profiling, is presented. A metrical analysis of a large collection of modern wild and domestic goats (Capra hircus aegargus and C. h. hircus) from Iran and Iraq clearly demonstrates that sex is by far the most significant factor affecting size in goats. In all post-cranial bones examined, those of males, even the unfused bones of males over 1 year of age, are absolutely larger than the bones of females. Region also plays a significant role in the size of these animals, but domestic status seems to have little impact. Similarly, a re-analysis of archaeological assemblages from Upland Sites the eastern fertile crescent shows no evidence of population-wide size reduction over a period that encompasses the transition from hunting to herding goats in the region, from the Middle Palaeolithic to the Early Neolithic. The apparent rapid reduction in the size of caprines during the early phases of domestication noted in earlier studies is likely attributable to a shift in the sex ratio of the adult breeding population of managed herds towards female domination, plus the differential destruction and loss of the bones of male animals killed at younger ages, as well as biases introduced by standard methodological practices. Building on the earlier work of Hesse, and using the empirical understanding of the factors influencing size in modern goats gained in this study, a new approach is proposed that combines both size and long-bone fusion data to construct high resolution, sex-specific age profiles of male and female goats that can be used to detect the hunting to herd management transition which marks the initial stages of the domestication process.     

A deciduous and permanent dental wear stage system for assessing the age of Trachypithecus sp. specimens (Colobinae, Primates)

Although Colobine monkeys are one of the most common prey hunted by Southeast Asian prehistoric humans, no data concerning tooth eruption and wear are available for these species. Dental wear eruption and attrition are used for attributing ages to individual fossils in order to construct mortality curves, and are also useful in reconstructing fossil life histories. Such wear sequences partly exist for Cercopithecines. Although Cercopithecines and Colobines are both bilophodont, they present significant differences in terms of diet, detailed tooth morphologies and occlusion. This paper aims to formulate a guide for the dental eruption and attrition of extant Trachypithecus specimens, the most folivorous of all the Colobines. We also propose to calibrate the eruption and wear stages that we define here with absolute ages available in the literature.     

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.     

Dental Microwear and Diet in Domestic Sheep (Ovis aries) and Goats (Capra Hircus): Distinguishing Grazing and Fodder-fed Ovicaprids using a Quantitative Analytical Approach

In recent years, dental microwear analysis has attracted considerable interest as a potential method for reconstructing ancient diet. This article presents results from research exploring the potential of dental microwear analysis in the reconstruction of domestic ungulate diet through the quantitative analysis of diet-microwear relationships in modern grazing and fodder-fed sheep and goats. Diet-related microwear patterning is identified in the modern populations examined and it is concluded that with investigation of a wider range of modern diets, dental microwear analysis will emerge as a valuable and insightful approach for the investigation of diet in ancient livestock.     

Testing the ‘Laacher See hypothesis’: tephra as dental abrasive

In a series of recent studies, changes in material culture and settlement pattern in the Late Glacial of Northern Europe have been linked to the eruption of the Laacher See volcano. This eruption occurred c. 13,000 years ago towards the end of the Allerød chronozone. It is argued that the tephra fall-out from this eruption set in motion significant demographic fluctuations along the northern periphery of Late Glacial human settlement and that these led to a number of material culture transformations. In particular, the emergence of the regionally distinct techno-complexes with large tanged points – the Bromme culture in southern Scandinavia and the Perstunian culture in northeastern Europe – and the temporary abandonment of central European regions are thought to relate to this eruption. While numerous archaeological datasets are in accord with this ‘Laacher See hypothesis’, the forcing mechanism or mechanisms that brought about these archaeologically visible changes have remained largely unexplored. A particular challenge is to explain how some of the culture-historical effects of the Laacher See eruption seem to change or become more pronounced with distance from the eruptive centre. We here investigate one potential middle-range link between the Laacher See eruption and Late Glacial fauna and foragers: tephra as dental abrasive. We use instrumented nanoindentation to quantitatively investigate tephra from a number of sites covering the medial and distal fall-out zones as well as the dental enamel of Homo sapiens and key prey species of Late Glacial foragers. Our results show that the Laacher See tephra contained particles roughly twice as hard as even the hardest portions of any of the teeth investigated. We also suggest that fluoride-induced weakening of dental enamel may have further aggravated tooth wear. These mechanisms may have acted in concert to produce elevated levels of, in particular, animal mortality, which in turn may have led to an abandonment of the affected landscapes.     

A novel method for integrated age and sex determination from archaeological cattle mandibles

Analysis of ancient cattle husbandry is compromised by the need for conventional analysis of sex and age at death to use different elements of the skeleton, usually from different individuals. We demonstrate a technique using aDNA acquired from cattle mandibles and combined with age-at-death estimation based on dental eruption in the same specimens. Application to small sample groups from two sites in Na h-Eileanan Siar (the Scottish Western Isles) show a high success rate, and demonstrates the potential for a more nuanced interpretation of ancient cattle husbandry.     

Comparing methods for analysing mortality profiles in zooarchaeological and palaeontological samples

In this study, I examine three methods that are currently used for comparing mortality profiles from zooarchaeological and palaeontological samples: (1) histograms with 10% of life‐span age classes; (2) boxplots showing tooth crown height medians; and (3) triangular plots of the proportions of young, prime and old animals. I assess the advantages and disadvantages of each method using data collected on two samples of Northern Yellowstone elk (Cervus elaphus nelsoni) with known, or cementum annuli‐determined, ages at death. One sample was hunted by wolves (n = 96), and the other was hunted by recent humans using rifles (n = 226). I tested each method with the known or cementum annuli age distributions and with age estimation techniques appropriate for archaeological assemblages. Histograms are best used when the relationship between dental eruption/attrition and age is well established so that individuals can be confidently assigned into 10% of life‐span groups, and when more than 30 or 40 individuals are present in the assemblage. Boxplots employ raw crown heights, thus removing the error introduced by assigning specimens to age classes, and therefore they allow the analysis of species where the relationship between dental eruption/attrition and age is unknown. Confidence intervals around the medians allow samples to be statistically compared. Triangular plots are easy to use and allow multiple samples and species to be considered simultaneously, but samples cannot be statistically compared. Modified triangular plots bootstrap samples to provide 95% confidence ellipses, allowing for statistical comparisons between samples. When possible, samples should be examined using multiple methods to increase confidence in the results. Copyright © 2005 John Wiley & Sons, Ltd.     

Implications of age variation and sexual dimorphism in modern equids for Middle Pleistocene equid taxonomy

Interspecific variation in the equid lineage is limited when compared with other large mammal lineages, while a considerable amount of intraspecific ecomorphological variation occurs. This has led to considerable debate regarding the taxonomic status of palaeontological and archaeological equid remains. The possible confounding impact of sex and age variation on analyses of archaeological equid remains has so far remained untested. This could be especially problematic when it is unknown whether an assemblage contains more than one equid species, breed or hybrid. Here, sex and age variation in modern equid species is examined and compared to variation in Pleistocene equid assemblages from northwest Europe. Sex variation in the longbones of modern equid species was found to be lower than variation over time. Similarly, age variation in dental elements of the same species is predominantly lower than diachronic variation, although caution needs to be taken when an archaeological assemblages consists mostly of elements at a similar wear stage. To assess whether late Middle Pleistocene caballoid horse fossils should be assigned to multiple species or be considered to form a monospecific group, the coefficients of variation for measurements on fossil horse remains were compared with those for modern equid specimens. Results indicate that the fossil assemblages are similarly variable to samples of modern material. Taken as a whole, the late Middle Pleistocene caballoid horse lineage is equally variable to an assemblage of modern ponies of a variety of different breeds. This implies that the variation observed between samples dating from different parts of the Middle Pleistocene can be characterised as intraspecific variation within a single species reflecting ecomorphological adaptations to the changeable Pleistocene climate. Copyright © 2010 John Wiley & Sons, Ltd.     

Reconstruction of Caprine Management and Landscape Use Through Dental Microwear Analysis: The Case of the Iron Age Site of El Turó de la Font de la Canya (Barcelona,Spain)

This paper presents the results of a pilot study using dental microwear analysis on 23 sheep and goat teeth dated to the 6th century BC from the Iron Age site of El Turó Font de la Canya (Barcelona, Spain). This study aimed to reconstruct livestock management practices and landscape use. The dental microwear pattern indicates that sheep and goats could have been grazing in the same area where vegetation was composed of shrubs, bushes and non-graminaceous plants on an eroded landscape, although additional supplies of fodder cannot be excluded. This scenario is compatible with the archaeological and palaeoenvironmental data which suggest a possibly increased territoriality, land degradation and an increase of woodland clearance during Iron Age in the North-east of the Iberian Peninsula. Furthermore, we applied two recent microwear approaches which provide more information about mortality events and the possibility of distinguishing between an intensive and extensive management. This paper demonstrates how this method can be used to better understand animal husbandry practices and landscape use in Late Prehistory.     

Epiphyseal fusion in brown bears: a population study of grizzlies (Ursus arctos horribilis) from Montana and Wyoming

This contribution presents results of a study of the timing of appendicular epiphyseal fusion in brown bears (Ursus arctos) based on the visual examination of 86 modern skeletons of grizzlies (U. a. horribilis) of known age and sex from the greater Yellowstone area, in the States of Wyoming and Montana (US). The timing of fusion in brown bears was compared with the (scant) information available for the black bear (Ursus americanus); both similarities and differences were found. It is still inconclusive whether the discrepancies stem from the methods of study (visual examination vs. X‐rays) or whether they reflect real difference in fusion ages. It is suggested that data derived from U. arctos can be used profitably to investigate mortality patterns of extinct bears such as the cave bear Ursus spelaeus. Copyright © 2008 John Wiley & Sons, Ltd.     

Collagen fingerprinting of archaeological bone and teeth remains from Domuztepe,South Eastern Turkey

We applied a recently developed method of collagen peptide mass fingerprinting for taxonomic identification in faunal remains to 111 specimens from the Neolithic site of Domuztepe in southeastern Turkey. Advances on the published technique allow us to move beyond the key domesticated fauna (sheep, goat, pig and cattle) to include non-domesticates (deer and gazelle, as well as humans). As the animal economy of Domuztepe was dominated by domestic sheep and goats, a large number of the samples tested were morphologically indistinguishable sheep/goat remains. A number of samples represented elements that provide information on age (i.e., mandibles) or sex (pelvis); thus, this represents the first major study to attempt to improve kill-off profiles using collagen fingerprinting. We also show that the collagen extracted from dentine is equally amenable to the proposed methodology as bone collagen.     

Dental pathology and diet at Apollonia,a Greek colony on the Black Sea

Dental pathology has the potential to provide insight into the composition of the diet and to reveal dietary differences based on age, sex and social status. Human skeletal remains from the Greek colonial site of Apollonia (5^th to 2^nd centuries BC) on the Black Sea coast of Bulgaria were analysed for various forms of dental pathology in order to: assess the prevalence of dental disease in the population; compare the dental pathology data from Apollonia with dietary data derived from ancient literary texts and from previous stable isotopic analysis of the colonists' remains; explore variations in dental disease with respect to age and sex; and compare the prevalence of dental pathology in the Apollonians with that of other Greek populations. The composition of the diet, as indicated by the dental pathology data, is consistent with the stable isotopic evidence from Apollonia and with the ancient literary texts, both of which indicate the consumption of a relatively soft, high carbohydrate diet. The higher frequency of dental caries, abscesses, calculus, and antemortem tooth loss in older adults compared with younger ones reflects the age‐progressive nature of these conditions. The lack of significant sex differences in caries, abscesses, calculus and tooth loss corresponds with the stable carbon and nitrogen isotopic data derived from bone collagen, which indicate no significant sex differences in the consumption of dietary protein. In contrast, these findings conflict with the ancient literary texts, which refer to distinct dietary differences between males and females, and with the stable carbon isotopic values derived from bone carbonate, which indicate sex differences with respect to the overall diet. Despite the lack of marked sex differences in dental pathology, overall trends point to subtle dietary differences between males and females. A greater degree of tooth wear in males also hints at possible sex differences in the use of the teeth as tools. Copyright © 2007 John Wiley & Sons, Ltd.     

Absolute age and tooth eruption and wear sequences in sheep and goat: determining age-at-death in zooarchaeology using a modern control sample

This paper seeks to improve our understanding of the relationship between mandibular tooth eruption and wear sequences and absolute age in modern sheep and goat. While the relationship between tooth eruption and wear and absolute age has been investigated for primitive breeds in parts of the Old World, our pilot study extends the applicability of this research to modern breeds and to another geographic region (North America). A modern control sample of two species of domestic caprines – Ovis aries (sheep) and Capra hircus (goats) from Manitoba, Canada – are used to evaluate the two major systems for analyzing mandibular tooth wear and eruption (Payne and Grant) and for assigning an absolute age-at-death. In order to compare the two systems, an absolute age for Grant's Mandibular Wear Stages was established for the first time, previously demonstrated only for Payne's system. The analysis confirmed that there is a very high correlation between the known age and estimated age based on tooth eruption and wear. However, Payne's system generated far coarser age-at-death profiles, which lowers its utility in constructing harvest profiles. Grant's system is recommended for ageing be utilized since it can yield more sensitive age estimations. In conclusion, it is possible to utilize the modern caprine breeds to establish the relationship between tooth eruption and wear and absolute age to reconstruct age and season of death of archaeological samples.     

Assessing the reliability of criteria used to identify mandibles and mandibular teeth in sheep, Ovis, and goats, Capra

Criteria developed to distinguish between the mandibles and mandibular teeth of sheep and goats are evaluated using modern specimens from the collections of the National Museum of Natural History and the Field Museum of Natural History. Certain teeth prove to be quite reliable in this regard (dP3, P3, P4). Other dental elements, however, are not reliable and should not be used in dental based identifications of these closely related species (dP4, M1, and mandibular bones). Overall, the identification of sheep dentition using these criteria is more reliable than it is for goats. However, the generally greater likelihood of incorrect identification of goat teeth and mandibles means that specimens identified as sheep are likely to contain high proportion of misidentified goats. Both the proportion of remains that can only be classified as ‘Ovis-Capra’ and the proportion of incorrectly identified teeth and mandibular bones varies with age, with identifications of younger and older animals less reliable than those of animals in the 1.5–6 year age range. Reliability of identifications increases when more criteria and more elements are used. Identifications based on whole mandibles with complete tooth rows are quite reliable. However, the proportion of specimens likely to be classified as ‘Ovis-Capra’ also increases in whole mandible identifications, especially in goats. Systematic differences in the proportions of indeterminate and incorrect identifications have a significant impact on species-level dentition-based harvest profiles. Recommendations are made for the use of dentition and long bone based harvest profiles in the study of sheep and goat exploitation strategies.     

Observations on Seasonality and Mortality from a Recent Catastrophic Death Assemblage

On 3 November 1991, a group of 150 pronghorn went over a cliff near Green River, Wyoming. This mortality site provides a unique opportunity to examine a number of characteristics of catastrophic death assemblages that may aid in the interpretation of archaeological bonebed sites. In 1993, the mandibles were collected for a study of seasonality and age estimation. Examination of seasonality revealed some variation in estimates by eruption/wear and cementum increments. Six percent of 86 fawn specimens exhibit eruption and wear more advanced than expected for a November third event, and 21% of 28 cementum increment estimates differ from the known November third mortality date by a month or more. These data suggest some degree of error is inherent in seasonality estimates that must be considered when interpreting seasonal distributions. Age estimates by eruption and wear reveal a distribution of pronghorn ages with many more juvenile animals than expected for a known “catastrophic” event. This may be explained by the pattern of seasonal hunting in a modern managed herd, which is likely to be very different than aboriginal hunting patterns. Age estimates by eruption/wear and cementum increment techniques failed to agree within six months in 48% of 29 test cases, with a tendency for cementum ages to be younger in 71% of specimens in which estimates of age differed. In general, the mandible assemblage exhibited more variability than one might expect for a single catastrophic kill event.     

An assessment of morphological criteria for discriminating sheep and goat mandibles on a large prehistoric archaeological assemblage (Kerma,Sudan)

This paper presents an assessment of all known dental and mandibular morphological criteria for differentiating sheep (Ovis aries) and goats (Capra hircus) using for the first time an archaeological sample of complete caprine skeletons (90 sheep and 13 goats) from burials at Kerma (Sudan, 3rd and 2nd millennia BC). The species determinations were assessed using cranial and post-cranial morphological criteria. Consequently, the reliability (percentage of correct determination) and efficiency (complementary percentage of intermediate scores i.e. neither sheep nor goat) of 38 individual dental criteria could be fully assessed using a prehistoric homogeneous domesticate population. We demonstrate that, for this sample, individual criteria for lacteal teeth are more reliable for sheep (sheep: 95 ± 3%) than the adult premolars (85 ± 5%) and molars (sheep: 88 ± 2%), whereas for goats premolar criteria were more reliable (83 ± 12%). For efficiency, lacteal dental criteria are better (goat: 97 ± 5%; sheep: 95 ± 3%) than those for premolar (goat: 85 ± 10%; sheep: 79 ± 5%) and molar (goat: 82 ± 6%; sheep: 83 ± 2). We also demonstrated that most isolated teeth can be determined with less than 10% error. However, on average, within specific age classes (0–1 year, 1–4 years and more than 4 years), isolated teeth increased in reliability and decreased in efficiency. The average reliability of the criteria for complete mandibles for each age class for goats and sheep was 100%, when the efficiency was 67, 40 and 50% for goats and over 90% for sheep. This is due to the effect of age on the efficiency of isolated criteria and the poor performance of specific criteria mainly those P3, M1 and M2. We conclude that separate species kill-off profiles are possible. The effect of age on dental criteria would not significantly change the interpretation for specific subsistence strategies focused on one particularly species.     

Maxillary Sinus Infection in a 19th‐Century Almshouse Skeletal Sample

In 1984, the Monroe County Parks Department in the Highland Park section of Rochester, New York, accidentally unearthed part of an unmarked cemetery while landscaping. The cemetery was in use from approximately 1826 to 1863 and was associated with the Monroe County Almshouse. Anthropological examination of dental and skeletal pathology revealed a high incidence of dental infection, known to occasionally be a causal agent of maxillary sinus infection. Therefore, maxillary sinus infections in this sample were studied to ascertain their relationship with dental infections, sex, and age at death. The maxillary sinuses of 99 skeletons were examined for evidence of infection. The presence, location, type and extent of dental infections in the posterior teeth were also recorded. Half the sample exhibited bone remodelling in the maxillary sinus (54 individuals). Dental infections were observed in 82 individuals. Forty‐eight demonstrated signs of dental infection and maxillary sinusitis. Statistical analysis revealed that dental infection and maxillary sinus infection were not statistically related. Rather, a rhinogenic method of infection seems likely, which would appear related to the squalid air quality the 19th‐century poor were exposed to in the almshouse and city tenements. Copyright © 2016 John Wiley & Sons, Ltd.