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.     

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.     

An exploration of character traits and linear measurements for sexing mountain gazelle (Gazella gazella) skeletons

The skeletal elements of mountain gazelle (Gazella gazella) have proven difficult to sex with statistical confidence due to wide overlap in the body size of the two sexes. We studied a sample of 53 modern mountain gazelle skeletons to determine which character traits and metric measurements best predict sex. The success of the character traits was determined using blind tests while the metrics were examined using discriminant function analysis. The most useful elements include the previously identified horn core, pubis and atlas, but also some new bone portions that preserve well in the archaeological record (e.g., distal tibia, distal metacarpal and metatarsal, and second phalanx). Surprisingly, two elements commonly used in sexing analyses (distal humerus and astragalus) were not among the most effective elements. Although cutting points and discriminant functions for sexing gazelle bone portions are presented here, they do not account for potential body size change and thus are not suited for direct application to archaeological assemblages. Instead, we provide guidelines for application to archaeological gazelle assemblages, most importantly a regression analysis that considers the sex ratios obtained from multiple measurements to predict the sex ratio of archaeological gazelle populations.     

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.     

Diameter of the human internal acoustic meatus and sex determination

We report the results of testing the diameter of the internal opening of the acoustic canal in the petrous part of the temporal bone for sex determination of skeletal remains. The method involves measuring the diameter using a suite of ordinary drills. The method is very simple and has the great advantage of utilising one of the sturdiest bone elements of the human skeleton. The method may be especially useful for the analyses of very fragmented skeletal remains or cremated bones, where the petrous bone may still be readily recognisable. The method was tested using a forensic sample of 113 left petrous bones with known sex. Intra‐ and inter‐observer testing was also performed. We found a statistically significant difference in diameter between males and females (means: males: 3.7 mm; females: 3.4 mm; P < 0.009). However, the low predictive value (70%) for correct sexing using two sectioning points ( < 3.0 mm = female; >3.5 mm = male) was disappointing. No additional accuracy was gained by employing both left and right petrous bones (a bilateral sample of 60 petrous bones was also tested), although left and right side diameter is highly correlated (R = 0.778; P = 0.0001). Copyright © 2005 John Wiley & Sons, Ltd.     

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.     

Biological mineral content in Iberian skeletal cremains for control of diagenetic factors employing multivariate statistics

The aim of this study was to define a strategy for a correct selection of bone samples by employing inductively coupled plasma optical emission spectroscopy (ICP-OES) for reconstructing the biological mineral content in bones through the determination of major elements, trace elements and Rare Earth Elements (REE, lanthanides) in skeletal cremains of ancient Iberians (III–II B.C), discovered in the Necropolis of Corral de Saus (Moixent, Valencia) between 1972 and 1979. The biological mineral content was determined taking into account diagenetic factors. A control method for a better reading of results was applied. To explore large geochemical datasets and to reduce the number of variables, Principal Component Analysis (PCA) was used, thus, providing a deeper insight into the structure of the variance of the dataset. PCA shows that the elemental profiles of bone and soil samples are clearly different. Bone samples obtained from the outer bone layer were shown to have a different elemental composition; more similar to soil samples than samples of the inner bone layer. PCA scores and loadings plots were preferred to dendrograms obtained using Cluster Analysis, due to the limits of the latter one to appreciate the spatial ordering of samples. Partial least squares discriminant analysis (PLS-DA), a frequently used supervised classification method, was applied to differentiate between degradation states of bone samples. PLS-DA results obtained in this study confirmed that changes derived from different burning conditions were associated with transformations in the mineral part of the bones. Accordingly, carbonized bones can be differentiated from cremated bones. Class assignment of bone samples with uncertain thermal conditions in dependence on their elemental composition has shown to be feasible. Consequently, for biochemical-archaeological studies the analysis and statistical classification of carbonized and cremated archaeological bones, as well as those exposed to unknown thermal conditions together with experiments in modern bones, are recommended.     

Canary islands aborigin sex determination based on mandible parameters contrasted by amelogenin analysis

Sex determination using mandible parameters is population dependent. In order to assess which measurements better characterize sex in prehispanic individuals from the Canary Islands, we blindly contrasted the results obtained by visual inspection and osteometric measurements with those obtained by molecular sexing using amelogenin ancient DNA analysis on teeth from the same material. Unambiguous sex classification was achieved by amplification of sex specific amelogenin alleles in 56 out of 76 mandibles (73.78% of the cases). Visual inspection led to a correct diagnosis in 66.04% of cases, with a greater proportion of errors for female (54.17%) than male (17.24%) mandibles. Osteometric measurements were able to assign sex correctly in 72.2% in the best of cases (mandibular height), a proportion similar to that obtained using a discriminant function (71.2%). By logistic regression analysis, ramus breadth, index ramus breadth/ramus height and mandibular length were the parameters independently related with a mistaken diagnosis of female sex, whereas bigonial width, ramus height and mandibular length were the parameters more closely and independently related to a mistaken diagnosis of male sex. In conclusion, diagnosis based on visual examination of the mandible or on its metric measurement only serves to roughly estimate sex with an accuracy of around 70% or less, at least among the prehispanic population from Gran Canaria. Amplification of amelogenin alleles leads to unambiguous identification of male and female alleles in 73.68% of cases, at least among the prehispanic population from Gran Canaria.     

Sex estimation using cervical dental measurements in an archaeological population from Iran

Sex estimation of skeletal remains is one of the major components of forensic identification of unknown individuals. Teeth are a potential source of information on sex and are often recovered in archaeological or forensic contexts due to their post-mortem longevity. Currently, there is limited data on dental sexual dimorphism of archaeological populations from Iran. This paper represents the first study to provide a dental sex estimation method for Iron Age populations. The current study was conducted on the skeletal remains of 143 adults from two Iron Age populations in close temporal and geographic proximity in the Solduz Valley (West Azerbaijan Province of Iran). Mesiodistal and buccolingual cervical measurements of 1334 maxillary and mandibular teeth were used to investigate the degree of sexual dimorphism in permanent dentition and to assess their applicability in sex estimation. Data was analysed using discriminant function analysis (SPSS 23), and posterior probabilities were calculated for all produced formulae. The results showed that incisors and canines were the most sexually dimorphic teeth, providing percentages of correct sex classification between 86.4 and 100 % depending on the measurement used. The combination of canines and other teeth improved significantly the level of correct sex classification. The highest percentages of sex classification were obtained by the combination of canines and incisors (100 %) and canines and molars (92.3 %). The present study provided the first reference standards for sex estimation using odontometric data in an Iranian archaeological population. Cervical measurements were found to be of value for sex assessment, and the method presented here can be a useful tool for establishing accurate demographic data from skeletal remains of the Iron Age from Iran.     

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.     

The effect of population variation on the accuracy of sex estimates derived from basal occipital discriminant functions

Multiple discriminant functions that estimate sex from the dimensions of the basal occipital have been published. However, as there is limited exploration of basal dimension variation between groups, the accuracy of these functions when applied to archaeological material is unknown. This study compares basal dimensions between four known sex-at-death post-medieval European samples and explores how metric differences impact on the accuracy of sex assessment discriminant functions. Published data from St Bride’s, London (n = 146) and the Georges Olivier collection, Paris (n = 68) were compared with new data from the eighteenth to nineteenth century Dutch Middenbeemster sample (n = 74) and the early twentieth century Rainer sample, Romania (n = 282) using independent t tests. The Middenbeemster and Rainer data were substituted into six published discriminant functions derived from the St Bride’s and the Georges Olivier samples, and the results were compared to their known sex. Multiple statistically significant differences were found between the four groups. Of the six discriminant functions tested, five failed to reach the published accuracy and fell below chance. In addition, even where the samples were statistically comparable in means, trends for difference also impacted the accuracy of discriminant functions. Enough variation in basal occipital dimensions existed in the European groups to decrease the accuracy of sex estimation discriminant functions to unusable. Possible inter-observer error, varying genetic, socioeconomic, and geographical factors are likely causes of dimension variation. This research further highlights the dangers of using sex estimation discriminant functions on samples that differ to the original derivative population and demonstrates the need for more rigorous testing.     

Foot anomalies in the Late Neolithic/Chalcolithic population exhumed from the rock cut cave of São Paulo 2 (Almada,Portugal)

The study of developmental abnormalities of the tarsal bones in a Portuguese Late Neolithic population was performed, as part of an ongoing research project that includes the evaluation of foot defects in Portuguese skeletal populations from Neolithic times to modern 20th century samples. Two accessory bones were found, calcaneum secundarium and os trigonum, and three non‐osseous coalitions were detected, calcaneonavicular, cuboid‐navicular and third metatarsal‐third cuneiform. The newly presented frequencies corresponded to other published sources, except for the frequency of calcaneum secundarium, higher than in previous studies (8.6% left bones; 15.2% right bones). This result suggests population homogeneity maybe due to geographic isolation and/or marriage customs although the exact pattern of inheritance of the majority of these foot anomalies is unknown. No apparent sex bias was detected and side could not be tested since these human remains were uncovered from a commingled funerary context. Copyright © 2010 John Wiley & Sons, Ltd.     

DNA analysis of archaeological rabbit remains from the American Southwest

Ancient DNA analysis was carried out on 20 archaeological rabbit remains from an early Pueblo II period site in Colorado (circa 1000 A.D.) to explore the possibility of obtaining accurate rabbit genus and species identifications. The presence of abundant rabbit remains at archaeological sites in the American Southwest indicates the importance of rabbit species in the subsistence economy and ritual activities of early aboriginal populations. The study of these remains is hindered by the difficulty of accurate identification due to the fragmentary nature of the bones and the lack of genus- and species-specific morphological features.A short cytochrome b gene fragment was amplified and sequenced to produce a genetic profile for each bone sample. At the genus level, the DNA identifications were consistent with those based on the analysis of mandible morphology for the majority of specimens. When compared to species-specific reference DNA sequences, Lepus americanus and Lepus californicus samples were easily identified. Identification of an unexpected L. americanus (snowshoe hare) from the remains provided new information concerning hunting ranges or exchange between groups in the region. Sylvilagus nuttallii and Sylvilagus audubonii, however, could not be confidently differentiated at this point due to the difficulty in obtaining accurate species-specific reference sequences.The inability to obtain such reference sequences can be a serious problem for DNA species identification of non-domestic animals that lack population-level genetic data and have few sequences available in GenBank. The lack of the DNA data increases the possibility that inappropriate reference sequences could be applied, resulting in false species identification even when authentic DNA is retrieved and amplified from ancient remains.     

New evidence for the antiquity of leprosy in early Britain

Examination of skeletons excavated in Dorset has probably produced the earliest example of leprosy known in northern Europe. The site, Poundbury Camp, Dorchester, was excavated under the direction of C. J. S. Green for the Dorchester Excavation Committee from 1966 to 1973. It is a Romano-British cemetery, apparently Christian, and the leprous bones are dated by their archaeological context to the middle of the fourth century AD.The specimen consists of the distal portions of right and left tibiae and fibulae, and the right and left feet. The right intermediate cuneiform is missing, but this may be a post-mortem loss. All parts of the skeleton above the mid-shaft of the tibiae and fibulae have been lost due to modern disturbance. It is therefore impossible to estimate the sex of the individual or its age, but the bones are certainly those of a mature adult.The following pathological changes were noted.     

Sex‐determination as a multivariate problem

The length, breadth, and thickness of the pubis bone of reindeer are used in the estimation of discriminant functions for sex‐determination of relatively recent bone material from Hardangervidda reindeer population. The method is considered to be most reliable (theoretically, 98 % reliable).     

Molecular and osteometric sexing of cattle metacarpals: a case study from 15th century AD Beja,Portugal

In the course of a zooarchaeological survey of Holocene sites in southern Portugal, a substantial size increase of cattle bones was noted following the Christian reconquista of the 11th–13th centuries AD. A size increase in the course of time within a lineage of domestic livestock is usually considered to represent animal improvement. However several other factors including sex may influence the average size of a sample of mammal bones – cattle exhibit considerable sexual size dimorphism, with bulls being larger than cows. A histogram of the distal widths of a large (n = 44) sample of cattle metacarpals from 15th century Beja (Alentejo, Portugal), revealed a bimodal distribution. It was assumed that the large measurements belonged to males and the small to females. In order to rule out the possibility of a post-Moslem change in the sex ratio of cattle, a sub-sample of 21 cattle metacarpals from Beja was selected and we used genetic markers to identify the sex of the animals to which these metacarpals belonged. The ancient DNA sex of all specimens agreed with the previously assumed sex as determined osteometrically. We conclude that the two nearly separated peaks for the metacarpal distal width measurements do indeed indicate sex. A similar bimodal distribution was obtained from another large but earlier sample of cattle metacarpals from Moslem Alcáçova de Santarém (9th–12th century AD). Although these have not been molecularly sexed and since osteometric sexing has now been validated, we conclude that both small (female) and large (male) peaks are smaller than the 15th century ones and that there was an overall size increase or improvement of cattle in this region. Why the Christians improved cattle is unclear, but a selection for larger beeves for meat is one possibility as is the selection of more robust cattle for power. The spread of the quadrangular or chariot plough in Iberia is known to have occurred at this time. We then use the genetically sexed metacarpals to determine which measurements provide reasonable distinction between the sexes. Both the distal width (BFd; as already noted by Svensson et al., 2008; in Swedish medieval cattle) and the width of the lateral condyle (WCL) offer the best distinction. We also used them as a reference ‘collection’ to sex the medieval and post-medieval cattle metacarpals from Launceston Castle in England. This re-visit of the Launceston data corroborates other evidence indicating increased specialisation (milk and veal) in post-medieval cattle husbandry in England.     

A system for classification and description of the horn cores of cattle from archaeological sites

A system is proposed for the classification and sexing of the horn cores of cattle recovered from archaeological sites. The cores are first divided into four groups depending on their length. The terms “small”, “short”, “medium” and “long horned” are given to these groups but bear no relation to the names used for modern breeds of cattle. After differentiation according to length, the sex of the core is designated by visual appraisal of the shape, curvature and angle of attachment of the cores to the frontal bones. It is not claimed that the sex of individual horn cores can always be established but from the sample of 80 cores that we tested by statistical analysis (presented in an appendix) it was evident that the categories based on length and assessment of sex did separate out as expected.     

A DNA test for sex identification in cattle confirms osteometric results

It is of vital importance to be able to sex identify cattle remains to understand the strategies and importance of cattle husbandry in an ancient society. This is usually done from osteoarchaeological assemblages and often relies on measurements of metapodials. The breadth measurement of the distal trochlea is considered an easy way to identify the sex. Bones from males appears to be easily distinguishable from female counterparts, although it has been complicated to find an external control for the morphological results. Here we investigate the reliability of these particular morphometrics for sex identifying cattle bones with molecular genetics. We use a sex discriminating single nucleotide polymorphism in the ZFXY gene and we apply it to DNA from the bones. To keep the fragment size short and suitable for ancient DNA we base the test on a SNP. The test confirms the osteological sex identification in all cases were DNA could be retrieved. This molecular method can also be used when no fragments suitable for osteological sex identification can be found or when the measurements are non-conclusive.     

Accurate sex identification of ancient human remains using DNA shotgun sequencing

Accurate identification of the biological sex of ancient remains is vital for critically testing hypotheses about social structure in prehistoric societies. However, morphological methods are imprecise for juvenile individuals and fragmentary remains, and molecular methods that rely on particular sex-specific marker loci such as the amelogenin gene suffer from allelic dropout and sensitivity to modern contamination. Analyzing shotgun sequencing data from 14 present-day humans of known biological sex and 16 ancient individuals from a time span of 100 to ∼70,000 years ago, we show that even relatively sparse shotgun sequencing (about 100,000 human sequences) can be used to reliably identify chromosomal sex simply by considering the ratio of sequences aligning to the X and Y chromosomes, and highlight two examples where the genetic assignments indicate morphological misassignment. Furthermore, we show that accurate sex identification of highly degraded remains can be performed in the presence of substantial amounts of present-day contamination by utilizing the signature of cytosine deamination, a characteristic feature of ancient DNA.     

Vascular Grooves on Human Femora and Tibiae as a Potential Activity‐related Trait

The presence of vascular grooves on the shafts of femora and tibiae was scored for a sample of human remains from a mass burial at Tell Majnuna, Syria, dated to the early fourth millennium bce . In the sample of 140 femora and 64 tibiae, many of which were damaged or fragmented, the grooves were most common on the femoral midshaft (31/108 = 28.7%) and on the proximal and middle shaft of the tibia (10/45 = 22.2 and 14/54 = 26.0%, respectively). For femoral midshafts, the difference in mean cross‐sectional size and shape indices between bones with and without vascular grooves was checked with multivariate analysis of variance for a sample of 51 bones. The presence of grooves appeared to correspond significantly with higher mean values of both indices. As the shape index is interpreted as an indicator of the level of terrestrial mobility and the size index may be used for sex assessment, it is possible that vascular grooves occur more frequently at the femoral midshafts of men and more active individuals, and thus they may be cautiously interpreted as another activity‐related trait. Copyright © 2012 John Wiley & Sons, Ltd.