Osteometric and molecular sexing of cattle metapodia

Sex identification of skeletal remains based on morphology is a common practice in Zooarchaeology. Knowledge of the sex distribution of slaughtered or hunted animals may help in the interpretation of e.g. hunting or breeding strategies. Here we investigate and evaluate several osteometric criteria used to assess sex of cattle (Bos taurus) metapodia using molecular sex identification as a control of the metric data. The bone assemblage used to assess these new criteria derives from the Eketorp ringfort in the southern parts of Öland Island in Sweden. One hundred metapodia were selected for molecular analysis of sex and we were able to genetically identify the sex of 76 of these elements. The combined results of the molecular and osteometric analyses confirm a significant size difference between females and males for several measurements for both metacarpals (Mc) and metatarsals (Mt). Our results show that some measurements are applicable for metapodials. These measurements include the slenderness indices such as the Mennerich’s index 1 and 3, as well as the distal breadth (Bd), the breadth between the articular crests (Bcr), and the maximum breadth of the lateral trochlea (BFdl). We show that they can be used for sexing of both metacarpals and metatarsals. The latter measurements offer an opportunity to study fragmented elements and thus a higher number of elements may be utilized for morphological sexing of archaeological bones. Size comparisons of Mc and Mt may also aid in the separation of bulls and oxen.     

Gazelle bone fat processing in the Levantine Epipalaeolithic

We investigate mountain gazelle (Gazella gazella) carcass processing to reconstruct resource intensification strategies during the Epipalaeolithic period of northern Israel. We adopt a multivariate taphonomic approach to identify the processes that most influenced bone survivorship in five gazelle assemblages. All of the assemblages are characterized by significant density-mediated biases, yet in situ attrition played a minimal role in assemblage formation. In contrast, the survivorship of hare (Lepus capensis) skeletons is not mediated by bone density indicating that different prey taxa experienced independent taphonomic histories. Both gazelle cortical and cancellous bone is highly fragmented and the degree of fragmentation and survivorship are strongly correlated with fat yields. Results of multiple tests point to intensive marrow and grease extraction as the primary determinant of gazelle bone survivorship. Although gazelle carcasses were intensively utilized throughout the Epipalaeolithic, the intensity of use is stable across the duration of the period.     

Genetic sexing to determine the optimal discriminant functions for the analysis of archaeological remains from El Hierro (Canary Islands)

A correct sex assignment of a given bone or bone fragment is of paramount importance for the archaeologist, anthropologist and in forensic medicine. Discriminant functions, combining several anthropometric measurements obtained from individuals with known sex are useful tools for this purpose, but it is essential to know exactly the sex from which the measures are obtained. This is an easy task in modern populations, but it is problematic in ancient ones, since even when the entire skeleton is available, diagnosis of sex is not 100% accurate. Sexing by genetic methods by amplifying the first intron of the amelogenin gene constitutes a much more accurate method for sexing bones and may be the gold standard for further elaboration of discriminant functions which may serve for sexing new bones dug up in future excavations. With this aim we have genetically sexed 52 (out of 59) tibiae belonging to the prehispanic population of El Hierro, in the Canary Islands, identifying 18 women and 34 men, and then, performed discriminant functions combining several anthropometric variables. These functions show a high accuracy in sex diagnosis (94.2%; area under ROC curve = 0.954 with the best of the functions), so that they allow correct sexing of tibiae or tibiae fragments (only proximal third, distal third or midshaft). Thus, genetic sexing obviates the problem of finding an accurate gold standard for the elaboration of discriminant functions for ancient bones. This method could be applied to other populations of different antiquity and different ethnicity.     

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.     

Sources of variation in carnivore tooth-mark frequencies in a modern spotted hyena (Crocuta crocuta) den assemblage,Amboseli Park,Kenya

Distributions and frequencies of carnivore tooth-marks on large mammal long-bone fragments are commonly used to infer the timing of hominin and carnivore access to prey resources in archaeofaunal assemblages. The strength of these inferences, however, is limited by a broad and currently inexplicable range of tooth-mark frequencies across experimental and archaeological assemblages. Controlling for this variation first requires that the sources be identified. Several sources of variation are examined here in an analysis of tooth-marked bone recovered from a modern spotted hyena (Crocuta crocuta) den assemblage in Amboseli Park, Kenya. Results indicate that tooth-mark frequencies: (1) depend on fragment size, (2) vary across mammals of different size classes, (3) are highly variable across equivalent portions of different long-bone elements, and (4) on certain long-bone portions are correlated with bone density and can be depressed in archaeological assemblages subjected to density-mediated attrition. Stronger inferences based on tooth-mark frequencies will require that such variation be taken into consideration, and methods for doing so are suggested.     

Gazelle exploitation in the early Neolithic site of Motza,Israel: the last of the gazelle hunters in the southern Levant

We studied the faunal remains from the Early and Middle PPNB site of Motza, Judean Mts., Israel, in order to gain insight into the economic basis prior to livestock husbandry, with a focus on gazelle hunting. Taphonomic analysis showed that bone preservation at the site was excellent. The subsistence economy in Motza was based on a broad spectrum of hunted species, with mountain gazelle (Gazella gazella) as the dominant prey, similar to many Epipalaeolithic and Pre-Pottery Neolithic sites in the southern Levant. We studied gazelle exploitation patterns, in order to learn about the interaction of humans with this species prior to ungulate domestication. Analysis of the demography of the gazelle herd, which included aging and sexing, revealed no age preferences and no selective culling. Moreover, the PPNB gazelle population of Motza does not exhibit allometric changes in morphology, that are allegedly correlated to increased hunting pressure on gazelle populations prior to livestock domestication.     

The Natufian economy at el-Wad Terrace with special reference to gazelle exploitation patterns

We carried out a detailed taphonomic and zooarchaeological analysis of the faunal remains from the new excavation of the Late Natufian layers of el-Wad Terrace. We focused on gazelle exploitation patterns and examined them within the context of the established Epipalaeolithic sequence from the coastal plain of Israel. Mountain gazelle (Gazella gazella) is the most heavily exploited species. The taphonomic history of the assemblage suggests minor loss of bones caused by post-depositional processes and indicates that bone destruction occurred during occupation. Cut marks from all stages of activities, absence of selective transport, and body part representation suggest that gazelle were butchered at the site. Analysis of gazelle sex composition shows male overrepresentation during the Natufian. Size trends show an increase of gazelle body-size during the Natufian in comparison to previous periods. The patterns of body-size increase show the same tendency in proximal and distal limb-bones. The trends in gazelle body-size from the Epipalaeolithic of the coastal plain do not demonstrate any sign of morphological dwarfism, increased variation, or allometric changes in the morphology of Natufian gazelles and thus do not support the previously suggested hypothesis of “proto-domestication”.     

Gazelle bone marrow yields and Epipalaeolithic carcass exploitation strategies in the southern Levant

We measure the bone marrow yields of mountain gazelle (Gazella gazella) carcasses to reconstruct gazelle exploitation strategies during the Epipalaeolithic periods in the southern Levant. We present experimentally derived data on the bone marrow content of seven fresh gazelle carcasses, determine the range of marrow yields among individuals of different sexes and seasons of death, and compare the new data to gazelle skeletal element abundances from five Epipalaeolithic assemblages from Israel. We found extensive variation in marrow fat content among individual gazelles. Animals with the highest marrow yields were killed in the spring while animals killed in the early autumn had lower fat contents. Nevertheless, our results suggest that gazelle marrow provided a reliable, albeit small fat resource for prehistoric foragers in all seasons. Strong relationships between bone fragmentation and marrow content demonstrate that Epipalaeolithic people preferentially processed bones with high marrow yields.     

Developmental Osteology of Cross‐bred Red Junglefowl (Gallus gallus L. 1758) and the Implications for Ageing Chickens from Archaeological Sites

We document the developmental osteology of a captive population of cross‐bred red junglefowl (Gallus gallus L. 1758) that were slaughtered at known ages from 6 days old until they reached maturity and explore the relationships that exist between bone size, maturity, body weight and sex. In doing so, we contribute to the body of knowledge concerning developmental osteology in domestic fowl, which has previously focussed upon ‘improved’ breeds. Comparison with archaeological material demonstrates that regression equations developed from the study population to determine age from bone length measurements are unreliable, even when samples with similar mean size for adult birds are compared. However, greater understanding of the maturity of domestic fowl more ‘primitive’ than most comparative material available for study is used to assist in the assignation of three age classes—chick, immature and adult—and thus facilitate more nuanced analyses of age‐at‐death patterns in faunal assemblages. Copyright © 2014 John Wiley & Sons, Ltd.     

Further developments in molecular sex assignment: a blind test of 18th and 19th century human skeletons

The identification of sex in human remains recovered from archaeological locations is important in order to understand the social and biological structure of past societies, and to reconstruct past population demographic events. Sex determination is usually based on morphological traits of the skeletons, with the drawback that most methods do not apply to juveniles and require well preserved remains. In cases where morphological methods cannot be used, or are ambiguous, methods of molecular sexing systems are an alternative. In this methodological study we tested and validated the accuracy and usefulness of a molecular sexing method based on the amelogenin gene using pyrosequencing. We did this in a double blind study of documented 18th and 19th century human remains.     

Radio – Ulnar Weight Index — is it a Useful Criterion for Sex Identification of the Human Skeleton?

Sex identification of human long bones has been studied by several investigators. Measurements of the radius and the ulna have also been reported as an indicator of sex by reference to separate parameters and/or to combinations of the parameters of a single bone. This study was designed to determine whether the radius and the ulna can provide reliable information for the sexing of human bones, as can the lower leg bones, if the forearm measurements include the weight index of the two bones as a parameter. The materials consisted of the dried radii and ulnae of 20 recently deceased Japanese males and 20 similar females. Almost all the dimensions exhibited statistically significant sex differences. The radio–ulnar weight index did not, however, differ between the sexes. In discriminant analysis, the rate of correct sex discrimination based on distances between various pairs of points was not improved by the inclusion of the radio–ulnar weight index. Therefore, the radio–ulnar weight index cannot be recommended as a parameter for the sexing of human bones.     

FOCUS: on the use of the petrous bone for estimating cranial abundance in fossil assemblages

Low representation of braincase bones in zooarchaeological assemblages suggests that skulls have been intensively processed by Levantine Epipalaeolithic foragers; most cranial elements are often unidentifiable and are considered poor candidates for quantifying crania. In contrast, the petrous bone is usually found complete, and was found to be easily identifiable to body size category. Use of the petrous bone in fossil assemblages analyses leads to better estimation of the occurrence of cranial elements, and thus of skeletal part representation. We therefore suggest use of the petrous bone for detecting bone destruction and selective transport in faunal assemblages.     

Sexing cattle horn‐cores: problems and progress

It has long been recognised that cattle horn‐cores are sexually dimorphic, and many methods have been developed using archaeological material for differentiating between specimens belonging to cows, bulls and oxen. Whilst these techniques have been adopted widely by zooarchaeologists, in particular those studying medieval and post‐medieval tannery and horn‐working assemblages, they are highly subjective and their reliability has never been tested using material from cattle of known sex. This paper seeks to redress the balance. It presents the results of a study of 19th and 20th century cattle horn‐cores, from animals of known age, sex and breed, which were examined and measured in order to test the validity of traditional horn‐core sexing techniques. Previously claimed traits of sexual variation are here refuted, and a new metrical threshold for separating the males and females of ‘medium‐horned’ and ‘long‐horned’ types are presented. Copyright © 2007 John Wiley & Sons, Ltd.     

Autochthony and orientation patterns in Olduvai Bed I: a re-examination of the status of post-depositional biasing of archaeological assemblages from FLK North (FLKN)

Recent excavations at FLK North (Olduvai Gorge, Tanzania) have produced new information on the orientation of archaeological materials at various levels of the site. This information includes the uniform distribution of material azimuths, which contrasts with previous inferences of highly patterned orientations of materials in the Bed I archaeological sites. Those previous inferences of patterned material orientations are based on Mary Leakey's 50-year-old drawings of artifact and fossil bone distribution, but are not verified by our precise measurements of archaeological objects made in situ. Nor do those previous results agree with the general lack of geological, geomorphological, and/or taphonomic data that would indicate significant post-depositional movement of archaeological materials in the sites. We argue here that Leakey's drawings are incomplete (only portions of each assemblage were drawn) and inaccurate in their representation of the original locations, shapes and orientations of most archaeological specimens. This argument is supported by several important mismatches in object representations between a photograph taken of a small portion of the FLK 22 Zinjanthropus site floor before the removal of the archaeological items, and the sketch of the same area drawn by Leakey. Thus, we conclude that primary orientation data of excavations (i.e., direct measurements taken from items) generated prior to object removal are the only valid indicators of the relative isotropy or anisotropy of these important paleoanthropological assemblages.     

Universal methodology for developing univariate sample-specific sex determination methods: an example using the epicondylar breadth of the humerus

In this paper we present a new methodology for developing sample-specific metric sex determination methods using unidentified individuals that can be applied to archaeological samples. This methodology does not require the assessment of sex of a large sample from pelvic morphological features as a first step in developing the method and instead is developed from a sample of individuals with sex unknown. The procedure involves using the overall mean of a measurement collected from the sample of unknowns as the discriminant criteria for determining the sex of the individuals in that same sample. Experiments with various sample sizes and sex ratios using distal humerus measurements from the Coimbra Collection (Portugal) suggest that allocation accuracies of 83–96% can be expected when the sample used to develop the method is greater than 40 individuals and the sex ratio is less than 1.5:1. The utility of the methodology is explored using the Lisbon Collection (Portugal) and an archaeological sample from Belleville (Canada) is tested as an example. The Lisbon Collection data indicate that joint measurements of long bones will provide the highest allocation accuracies. The results from the Belleville sample confirm that humerus joint measurements consistently provide the highest allocation accuracies (88–100%) even when the sex ratio in the sample used to develop the method is estimated at 1.9:1.     

Estimating meagre (Argyrosomus regius) size from otoliths and vertebrae

This study presents a method for predicting meagre (Argyrosomus regius) body size (total length) from otoliths and vertebrae recovered from archaeological sites. The method involves regression equations calculated from a reference collection of 36 meagre skeletons and 113 meagre otoliths (sagitta) and allows the simultaneous estimation of original body size and minimum number of individuals (MNI) from archaeological bone structures. We selected the following measurements to predict meagre body size: greatest dorso-ventral height, greatest mediolateral breadth, and greatest anteroposterior length of the vertebrae centra; maximum anteroposterior length, medial anteroposterior length, and dorso-ventral height of the sagitta. Our results show that the original body size of meagre can be accurately predicted from many bone measurements (r² range: 0.921–0.992). We exemplify the use of the regressions in the assessment of size variation and MNI of meagre from four Portuguese Mesolithic sites. We show that regression results provide additional insight into the significant role that this fish played in the subsistence of coastal fisher-hunter-gatherers, who targeted medium-sized animals but were also capable of acquiring rather larger specimens.     

Sex identification from the distal fibula

This study was designed to determine whether the fibula, which is one of the least studied long bones, can provide reliable information for sexing of human bones, provided that one condition is satisfied, namely, its distal end is available for measurement. The materials consisted of the dried fibulae of 71 Japanese males and 35 females whose names, ages and sex were known. The distal end of the fibula was measured with respect to five novel dimensions that are closely related to the soft tissues that had been attached to the bone surface. Highly significant sex differences were found when all parameters examined were considered together. The differences for separate items were not, however, sufficient for sex discrimination. Discriminant analysis was performed using the five parameters and yielded the correct sex with 90. 6 per cent accuracy for the entire group of specimens. This degree of accuracy suggests the utility of the present method for sexing human bones, in particular, in osteoarchaeological situations.     

Sexual dimorphism in limb bones of ibex (Capra ibex L.): mixture analysis applied to modern and fossil data

Estimating sex ratios of fossil bone assemblages is an important step in the determination of demographic profiles, which are essential for understanding the palaeobiology and palaeoethology of any particular species, as well as its exploitation patterns by humans. This is especially true for ibex (Capra ibex), which was a main source of food for hominids during Pleistocene times. Classical methods for determining sexual dimorphism and sex ratio, such as analyses using uni‐ and bivariate plots, are based on an arbitrary fixing of limits between sexes. Here we use a more robust statistical method termed mixture analysis (MA) to determine the sex of postcranial remains (long bones, metapodials and tarsals) from ibex. For the first time, we apply MA to both a modern and a fossil sample of one species, by using metric data taken from (i) a collection of present‐day ibex skeletons and (ii) a Palaeolithic sample of the same species. Our results clearly show that the forelimb (humerus and radius) is more dimorphic than the hindlimb (femur and tibia) and is therefore better suited for sexing ibex. It also appears that metapodials should be used carefully for estimating sex ratios. On the basis of these results, we propose a classification of bone measurements that are more or less reliable for sexing ibex. The results of MA applied to the ibex fossil bones from the Upper Palaeolithic site of the Observatoire (Monaco) lead us to the conclusion that this assemblage consists of a majority of males. The quantitative estimations calculated by the MA make it possible to compare the size of Pleistocene and modern ibex for the whole set of variables used in this study. Copyright © 2006 John Wiley & Sons, Ltd.     

Bone Mineral Density of Wild Turkey (Meleagris gallopavo) Skeletal Elements and its Effect on Differential Survivorship

Zooarchaeologists recognize that density-mediated attrition is a bias that demands consideration in the analysis of archaeofaunal samples. This paper presents bone mineral density values (aereal and volumetric) for the wild turkey (Meleagris gallopavo) and represents the first application of Dual-energy X-ray Absorptiometry (DEXA) to birds. The relationship between density and the survivorship of avian skeletal elements and portions is demonstrated by examining 20 assemblages from the archaeological record of the northeastern United States. The results suggest that density may account for the differential survivorship of least 35% of the samples tested. Further analysis of a single site demonstrates the importance of examining bone mineral density when interpreting past bird hunting and use.     

A new approach to sexual diagnosis in past populations. Practical adjustments from Van Vark's procedure

Determination of sex is a key aspect in the study of past populations. Bias in skeletal sexing is well known, however, and depends upon the completeness of the skeletal remains and the representativeness of reference samples. In order to correct these difficulties, the authors propose practical adjustments to Van Vark's well‐known procedure. Two fundamental aspects are considered to reduce the bias of sex allocation. First, we propose to increase the effectiveness of sexing during the first step (primary diagnosis only from the pelvic bone). Second, to improve the final step (secondary diagnosis from the extra‐pelvic skeleton), we consider posterior probabilities as essential. These two practical adjustments are successfully tested in a sample of known sex and lead to a classification with 94.5% accuracy. These results significantly improve sex determination in archaeological samples and therefore contribute to a better understanding of past populations. Copyright © 1999 John Wiley & Sons, Ltd.