Sotiris K. Manolis

Sexual Dimorphism of the Arm Bones in a Modern Greek Population

Abstract:  Several studies have shown that sex determination methods based on measurements of the skeleton are population specific. Metric traits of the long bones of the arm have been reported as reliable indicators of sex. This study was designed to determine whether the three long bones of the arm can be used for sex determination on a skeletal population from Greece. The material used consists of the arm bones of 204 adult individuals (111 males and 93 females) coming from the Modern Human Skeletal Collection of the University of Athens. The age range is 19–96 years for males and 20–99 years for females. The maximum lengths and epiphyseal widths were measured in the long bones of the arm (humerus, radius, and ulna). The discriminant analysis of the metrical data of each long bone gave very high discrimination accuracies. The rate of correct sex discrimination based on different long bones ranges from 90.30% (ulna) to 95.70% (humerus). In addition, intra‐ and inter‐observer error tests were performed. These indicated that replication of measurements was satisfactory for the same observer over time and between observers. The results of this study show that metric characteristics of the arm bones can be used for the determination of sex in skeletal remains from Greece and that bone dimensions are population specific.

Sex determination using metatarsal osteometrics from the Athens collection

The determination of sex in skeletal remains performed by forensic anthropologists or bioarchaeologists typically relies on the analysis of quantitative and qualitative characteristics of the skeleton. In this regard, the most widely used features belong to the pelvic and cranial areas, but these are often not available in forensic or archaeological contexts. The objective of this study is to determine the extent of dimorphism exhibited by the metatarsal bones in order to examine their utility in the metric determination of sex in skeletal remains of Greek origin. A further objective is the development of linear discriminant function equations for sex determination based on the metatarsals from a contemporary Greek population. The skeletal sample used in this study is comprised of 1595 metatarsals (left and right), corresponding to 186 adult individuals (97 males, 89 females) and belongs to the documented collection of the University of Athens. The results suggest that metatarsal bones exhibit significant sexual dimorphism and the accuracy of the discriminant function equations for sex determination range from 80.7% to 90.1% (or 77.9-86.4% cross-validated). Thus, metatarsal bones may be used for sex determination in skeletal remains from Greece in addition to other sexing techniques.

Sex determination using metacarpal biometric data from the Athens Collection

Forensic anthropologists and bioarchaeologists usually determine sex by analyzing quantitative and qualitative characters of the human skeleton. In general, the pelvis and skull are the skeletal parts used most often, but in many cases these parts are missing or fragmentary. In such circumstances, it is necessary to use techniques based on other skeletal elements. The primary aim of this work is to determine whether metacarpals can be used for the determination of sex specifically in a Greek population. A secondary step is to describe and develop linear discriminant function equations for sex determination based on a contemporary Greek population using metacarpal biometric data. The skeletal sample of the modern Greeks is housed at the National and Kapodistrian University of Athens (NKUA) is comprised of 993 metacarpals (left and right), corresponding to 151 adult individuals (84 males and 67 females). The correct sex classification reached an accuracy of 83.7-88.1% for left and 83.8-89.7%, for right metacarpals. Our results suggest that metacarpals can be used for sexing in bioarchaeological, and forensic studies, in addition to other sex determination techniques.

Sex determination by three-dimensional geometric morphometrics of the palate and cranial base

The purpose of this study is to assess sexual dimorphism in the palate and base of adult crania using three-dimensional geometric morphometric methods. The study sample consisted of 176 crania of known sex (94 males, 82 females) belonging to individuals who lived during the 20th century in Greece. The three-dimensional co-ordinates of 30 ectocranial landmarks were digitized using a MicroScribe 3DX contact digitizer. Generalized Procrustes Analysis (GPA) was used to obtain size and shape variables for statistical analysis. Three discriminant function analyses were carried out: (1) using PC scores from Procrustes shape space, (2) centroid size alone, and (3) PC scores of GPA residuals which includes InCS for analysis in Procrustes form space. Results indicate that there are shape differences between sexes. In males, the palate is deepest and more elongated; the cranial base is shortened. Sex-specific shape differences for the cross-validated data give better classification results in the cranial base (77.2%) compared with the palate (68.9%). Size alone yielded better results for cranial base (82%) in opposition to palate (63.1%). As anticipated, the classification accuracy improves when both size and shape are combined (90.4% for cranial base, and 74.8% for palate).

Sex determination from the calcaneus in a 20th century Greek population using discriminant function analysis

The skull and post-cranium have been used for the determination of sex for unknown human remains. However, in forensic cases where skeletal remains often exhibit postmortem damage and taphonomic changes the calcaneus may be used for the determination of sex as it is a preservationally favored bone. The goal of the present research was to derive discriminant function equations from the calcaneus for estimation of sex from a contemporary Greek population. Nine parameters were measured on 198 individuals (103 males and 95 females), ranging in age from 20 to 99 years old, from the University of Athens Human Skeletal Reference Collection. The statistical analyses showed that all variables were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 70% to 90% for the univariate analysis, 82.9% to 87.5% for the direct method, and 86.2% for the stepwise method. Comparisons to other populations were made. Overall, the cross-validated accuracies ranged from 48.6% to 56.1% with males most often identified correctly and females most often misidentified. The calcaneus was shown to be useful for sex determination in the twentieth century Greek population.

Sex determination from the talus in a contemporary Greek population using discriminant function analysis

The determination of sex is an important part of building the biological profile for unknown human remains. Many of the bones traditionally used for the determination of sex are often found fragmented or incomplete in forensic and archaeological cases. The goal of the present research was to derive discriminant function equations from the talus, a preservationally favoured bone, for sexing skeletons from a contemporary Greek population. Nine parameters were measured on 182 individuals (96 males and 86 females) from the University of Athens Human Skeletal Reference Collection. The individuals ranged in age from 20 to 99 years old. The statistical analyses showed that all measured parameters were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 65.2% to 93.4% for the univariate analysis, 90%-96.5% for the direct method and 86.7% for the stepwise method. Comparisons to other populations were made. Overall, the cross-validated accuracies ranged from 65.5% to 83.2% and males were most often correctly identified. The talus was shown to be useful for sex determination in the modern Greek population.

Guidelines for the Recognition of Cemetery Remains in Greece

Forensic pathologists frequently consult anthropologists for the identification of skeletonized human remains. These remains may be the result of criminal activity or remains that were unearthed because of erosion, or during construction projects. In some cases, human remains that had been previously buried in a cemetery may be the subject of a forensic investigation. Early recognition of cemetery remains prevents unnecessary efforts and conserves precious resources. One of the key characteristics of cemetery remains is the presence of embalmed tissue. However, there are countries where embalming is not a common practice, and other clues must be sought for identifying previously buried remains. Current funerary customs in Greece and, in particular, the tradition of exhumations result in a large number of misplaced human remains. The present study presents examples of cemetery remains from Greece and offers guidelines for recognizing changes on skeletal remains that may be indicative of a cemetery origin. Location of discovery, condition of the remains, and the types of associated artifacts are all factors that aid forensic anthropologists in identifying cemetery remains.

Sex determination by three-dimensional geometric morphometrics of the vault and midsagittal curve of the neurocranium in a modern Greek population sample

The aim of this study is to assess sexual dimorphism of adult crania in the vault and midsagittal curve of the vault using three-dimensional geometric morphometric methods. The study sample consisted of 176 crania of known sex (94 males, 82 females) belonging to individuals who lived during the 20th century in Greece. The three-dimensional co-ordinates of 31 ecto-cranial landmarks and 30 semi-landmarks were digitized using a MicroScribe 3DX contact digitizer. Generalized Procrustes analysis (GPA) was used to obtain size and shape variables for statistical analysis. Shape, size and form analyses were carried out by logistic regression and three discriminant function analyses. Results indicate that there are shape differences between sexes. Females in the region of the parietal bones are narrower and the axis forming the frontal and occipital bones is more elongated; the frontal bone is more vertical. Sex-specific shape differences give better classification results in the vault (79%) compared with the midsagittal curve of the neurocranium (68.8%). Size alone yielded better results for cranial vault (82%), while for the midsagittal curve of the vault the result is poorer (68.1%). As anticipated, the classification accuracy improves when both size and shape are combined (89.2% for vault, and 79.4% for midsagittal curve of the vault). These latter findings imply that, in contrast to the midsagittal curve of the neurocranium, the shape of the cranial vault can be used as an indicator of sex in the modern Greek population.

Sex determination by three-dimensional geometric morphometrics of craniofacial form.

SUMMARY The purpose of the present study is to define which regions of the cranium, the upper-face, the orbits and the nasal are the most sexually dimorphic, by using three-dimensional geometric morphometric methods, and investigate the effectiveness of this method in determining sex from the shape of these regions. The study sample consisted of 176 crania of known sex (94 males, 82 females) belonging to individuals who lived in Greece during the 20(th) century. The three-dimensional co-ordinates of 31 ecto-cranial landmarks were digitized using a MicroScribe 3DX contact digitizer. Goodalls F-test was performed in order to compare statistical differences in shape between males and females. Generalized Procrustes Analysis (GPA) was used to obtain size and shape variables for statistical analysis. Shape, Size and Form analyses were carried out by logistic regression and discriminant function analysis. The results indicate that there are shape differences between the sexes in the upper-face and the orbits. The highest shape classification rate was obtained from the upper-face region. The centroid size of the caraniofacial and the orbital regions was smaller in females than males. Moreover, it was found that size is significant for sexual dimorphism in the upper-face region. As anticipated, the classification accuracy improves when both size and shape are combined. The findings presented here constitute a firm basis upon which further research can be conducted.

A Simple Technique for Imaging the Human Skeleton Using a Flatbed Scanner

Abstract:  A simple technique for imaging the human skeleton with a flatbed scanner is presented using the auricular surface of the ilium as an example. A flatbed scanner with resolution capabilities of 600 dpi or greater allows for images of human bones. The auricular surface of the ilium was selected to demonstrate this technique as it is a fairly three‐dimensional area that can be difficult to record photographically. Fifty left ilia of various ages at death from the Athens Collection were selected from which three observers (SCF, CE, and IM) scored the morphology of the auricular surface using a well‐established aging method. Observations were taken of the dry bone, of digital photographs of the bone, and of scanned images of the bone, and in that sequence. Results indicate that scores of scanned images are equivalent or better than digital images of the same ilia. This technique allows for sharing data electronically with ease.