Sex estimation Dotaz Zobrazit nápovědu
Sex estimation is a task of utmost importance in forensic anthropology and bioarcheology. Along with the pelvic bone, the skull is the most important source of sexual dimorphism. On the human skull, the upper third of the face (i.e., the frontal bone) is one of the most significant sexually dimorphic structures useful in anthropological research, especially when studied by methods of virtual anthropology. This study was focused on sex estimation using the form and shape of the external surface of the frontal bone with or without the inclusion of its sinuses. The study sample consisted of 103 cranial CT images from a contemporary Czech population. Three-dimensional virtual models of the frontal bones and sinuses were analyzed using geometric morphometrics and multidimensional statistics: coherent point drift-dense correspondence analysis (CPD-DCA), principal component analysis (PCA), and support vector machine (SVM). The whole external frontal surface was significantly different between males and females both in form and shape. The greatest total success rate of sex estimation based on form was 93.2%, which decreased to 86.41% after crossvalidation, and this model identified females and males with the same accuracy. The best estimation based on shape reached a success rate of 91.26%, with slightly greater accuracy for females. After crossvalidation, however, the success rate decreased to 83.49%. The differences between sexes were significant also in the volume and surface of the frontal sinuses, but the sex estimation had only 64.07% accuracy after crossvalidation. Simultaneous use of the shape of the frontal surface and the frontal sinuses improved the total success rate to 98.05%, which decreased to 84.46% after crossvalidation.
- Klíčová slova
- Forensic anthropology, Frontal bone, Frontal sinuses, Geometric morphometrics, Sex estimation, Sexual dimorphism,
- MeSH
- čelní kost anatomie a histologie diagnostické zobrazování MeSH
- lebka anatomie a histologie diagnostické zobrazování MeSH
- lidé MeSH
- pohlavní dimorfismus MeSH
- soudní antropologie metody MeSH
- určení pohlaví podle kostry metody MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Sex estimation methods based on skeletal remains vary on the selection of skeletal element, data acquisition and statistical approach resulting in variable classification accuracies that are highly dependent on the sample population. The only exception of this rule seems to be the os coxa, that appears to differ consistently between males and females across the globe. Currently sex estimation based on the os coxa can be easily estimated by taking ten measurements, inputting these in the DPS2 software and getting a sex estimate and the probability of correct group assessment. The performance of the software is highly reliable as confirmed by a validation study by Brůžek et al. (2017). Yet, there are still many populations not represented in the reference sample used to develop the software. The current study aimed to validate DPS2 using a sample from Crete, Greece. A total of 133 os coxae were measured following instructions on DSP2. Data were used to estimate sex with the software and to create population specific formulae for Greeks. DSP2 classified 117/133 (85.7%) of the sample with over 95% posterior probability (PP) of correct classification. Of the individuals classified with over 95% PP, only 3 were misclassified (2.6%).The best population specific formula only improved this percentage by 2.1% which indicates that DSP2 is a reliable tool for sex estimation in the Greek sample and it is recommended as method of choice in sex estimation of remains of unknown ancestry. If Greek ancestry is confirmed, population-specific formulae can be used in conjunction with DSP2 for a more reliable sex estimation.
- Klíčová slova
- DSP2, Forensic anthropology, Greece, Pelvis, Sex estimation,
- MeSH
- diskriminační analýza MeSH
- lidé MeSH
- pánevní kosti anatomie a histologie MeSH
- software * MeSH
- určení pohlaví podle kostry * MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
- Geografické názvy
- Řecko MeSH
This paper introduces an automated method for estimating sex from cranial sex diagnostic traits by extracting and evaluating specialized morphometric features from the glabella, the supraorbital ridge, the occipital protuberance, and the mastoid process. The proposed method was developed and evaluated using two European population samples, a Czech sample comprising 170 crania reconstructed from anonymized CT scans and a Greek sample of 156 crania from the Athens Collection. It is based on a fully automatic algorithm applied on 3D models for extracting sex diagnostic morphometric features which are further processed by computer vision and machine learning algorithms. Classification accuracy was evaluated in a population specific and a population generic 2-way cross-validation scheme. Population-specific accuracy for individual morphometric features ranged from 78.5 to 96.7%, whereas population generic correct classification ranged from 71.7 to 90.8%. Combining all sex diagnostic traits in multi-feature sex estimation yielded correct classification performance in excess of 91% for the entire sample, whereas the sex of about three fourths of the sample could be determined with 100% accuracy according to posterior probability estimates. The proposed method provides an efficient and reliable way to estimate sex from cranial remains, and it offers significant advantages over existing methods. The proposed method can be readily implemented with the skullanalyzer computer program and the estimate_sex.m GNU Octave function, which are freely available under a suitable license.
- Klíčová slova
- Cranial sex diagnostic traits, European populations, Morphometric feature extraction, Sex discriminant models, Supervised machine learning,
- MeSH
- algoritmy * MeSH
- dospělí MeSH
- kefalometrie * MeSH
- lebka anatomie a histologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- pohlavní dimorfismus MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- software MeSH
- soudní antropologie metody MeSH
- určení pohlaví podle kostry metody MeSH
- zobrazování trojrozměrné MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika etnologie MeSH
- Řecko etnologie MeSH
Vertebral measurements have been shown to provide accurate classification of sex. However, the use of vertebral discriminant functions (DFs) in forensic anthropology and bioarchaeology is limited due to the unknown degree of their population specificity. Additionally, the performance of vertebral DFs has not yet been assessed at higher posterior probability thresholds. In this study, we tested the performance of previously published DFs for sex classification from Th12 and L1 vertebrae within a range of 0.5-0.95 posterior probabilities in a model of geographically distant population based on an autopsy Central European (CE) sample (Czech Republic; n=72) from the 1930s. Further, we derived new pooled DFs from a sample representing ecogeographically diverse populations, new DFs derived from the autopsy CE sample, and new Medieval CE DFs derived from the Pohansko sample (n=129) and evaluated their performance at our testing autopsy CE sample. Most vertebral measurements showed population specificity in sex assessment. However, we identified two Th12 measurements (anteroposterior body diameter and mediolateral body diameter) usable for sex estimation across populations. We showed that the accuracy of vertebral DFs can be increased to 95% of correctly classified individuals in up to 64% of the studied sample by setting a higher posterior probability threshold. Finally, we showed that even the DFs derived from relatively small subsamples (30% of the population size) can provide accurate sex classification. This finding highlights the applicability of the hybrid approach in sex classification from vertebrae. To facilitate sex classification from vertebrae, we provide a software tool for sex classification from any vertebral measurement and reference samples tested in this study including the previously published DFs.
- Klíčová slova
- Central Europe, Discriminant function analysis, Forensic anthropology population data, Posterior probability, Sex classification, Sexual dimorphism,
- MeSH
- bederní obratle anatomie a histologie MeSH
- diskriminační analýza MeSH
- hrudní obratle anatomie a histologie MeSH
- lidé MeSH
- soudní antropologie MeSH
- určení pohlaví podle kostry metody MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
In this study we tested classification performance of a sex estimation method from the mandible originally developed by Sella-Tunis et al. (2017) on a heterogeneous Israeli population. Mandibular linear dimensions were measured on 60 CT scans derived from the Czech living population. Classification performance of Israeli discriminant functions (DFs-IL) was analyzed in comparison with calculated Czech discriminant functions (DFs-CZ) while different posterior probability thresholds (currently discussed in the forensic literature) were employed. Our results comprehensively illustrate sensitivity of different discriminant functions to population differences in body size and degree of sexual dimorphism. We demonstrate that the error rate may be biased when presented per posterior probability threshold. DF-IL 1 showed least sensitivity to population origin and fulfilled criteria of sufficient classification performance when applied on the Czech sample with a minimum posterior probability threshold of 0.88 reaching overall accuracy ≥ 95%, zero sex bias, and 80% of classified individuals. The last parameter was higher in DF-CZ 1 which was the main difference between those two DFs suggesting relatively low dependance on population origin. As the use of population-specific methods is often prevented by complicated assessment of population origin, DF-IL 1 is a candidate for a sufficiently robust method that could be reliably applied outside the reference sample, and thus, its classification performance deserves further testing on more population samples.
- Klíčová slova
- Czech population, Logistic regression, Mandible, Population specificity, Posterior probability, Sex estimation,
- Publikační typ
- časopisecké články MeSH
Sex is a biological trait fundamental to the study of hominin fossils. Among the many questions that can be addressed are those related to taxonomy, biological variability, sexual dimorphism, paleoobstetrics, funerary selection, and paleodemography. While new methodologies such as paleogenomics or paleoproteomics can be used to determine sex, they have not been systematically applied to Pleistocene human remains due to their destructive nature. Therefore, we estimated sex from the coxal bone of the newly discovered pelvic remains of the Regourdou 1 Neandertal (Southwest France, MIS 5) based on morphological and metric data employing two methods that have been recently revised and shown to be reliable in multiple studies. Both methods calculate posterior probabilities of the estimate. The right coxal bone of Regourdou 1 was partially reconstructed providing additional traits for sex estimation. These methods were cross validated on 14 sufficiently preserved coxal bones of specimens from the Neandertal lineage. Our results show that the Regourdou 1 individual, whose postcranial skeleton is not robust, is a male, and that previous sex attributions of comparative Neandertal specimens are largely in agreement with those obtained here. Our results encourage additional morphological research of fossil hominins in order to develop a set of methods that are applicable, reliable, and reproducible.
- Klíčová slova
- Hip bone, Neandertal, Probabilistic sex diagnosis, Regourdou, Sex attribution, Sexual dimorphism,
- MeSH
- genomika MeSH
- Hominidae * MeSH
- lidé MeSH
- neandertálci * anatomie a histologie MeSH
- paleontologie MeSH
- zkameněliny MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Francie MeSH
In the framework of forensic anthropology osteometric techniques are generally preferred over visual examinations due to a higher level of reproducibility and repeatability; qualities that are crucial within a legal context. The use of osteometric methods has been further reinforced by incorporating statistically-based algorithms and large reference samples in a variety of user-friendly software applications. However, the continued increase in admixture of human populations have made the use of osteometric methods for estimation of ancestry much more complex, which confounds one of major requirements of ancestry assessment - intra-population homogeneity. The present paper tests the accuracy of ancestry and sex assessment using four identification software tools, specifically FORDISC 2.0, FORDISC 3.1.293, COLIPR 1.5.2 and 3D-ID 1.0. Software accuracy was tested in a sample of 174 documented human crania of Brazilian origin composed of different ancestral groups (i.e., European Brazilians, Afro-Brazilians, and Japanese Brazilians and of admixed ancestry). The results show that regardless of the software algorithm employed and composition of the reference database, all methods were able to allocate approximately 50% of Brazilian specimens to an appropriate major reference group. Of the three ancestral groups, Afro-Brazilians were especially prone to misclassification. Japanese Brazilians, by contrast, were shown to be relatively easily recognizable as being of Asian descent but at the same time showed a strong affinity towards Hispanic crania, in particularly when the classification based on FDB was carried out in FORDISC. For crania of admixed origin all of the algorithms showed a considerable higher rate of inconsistency with a tendency for misclassification into Asian and American Hispanic groups. Sex assessments revealed an overall modest to poor reliability (60-71% of correctly classified specimens) using the tested software programs with unbalanced individual rates for males and females. The highest and atypically balanced rate of classification for sex assessment was provided by COLIPR software, which reached 78% of correctly assessed crania.
- Klíčová slova
- 3D-ID, Ancestry assessment, Brazilian crania, FORDISC, Sex assessment,
- MeSH
- lidé MeSH
- populační skupiny etnologie MeSH
- software normy MeSH
- soudní antropologie * metody MeSH
- určení pohlaví podle kostry metody MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- validační studie MeSH
- Geografické názvy
- Brazílie MeSH
Proteomics has become an attractive method to study human and animal material, biological profile, and origin as an alternative to DNA analysis. It is limited by DNA amplification in ancient samples and its contamination, high cost, and limited preservation of nuclear DNA. Currently, three approaches are available to estimate sex-osteology, genomics, or proteomics, but little is known about the relative reliability of these methods in applied settings. Proteomics provides a new, seemingly simple, and relatively non-expensive way of sex estimation without the risk of contamination. Proteins can be preserved in hard teeth tissue (enamel) for tens of thousands of years. It uses two sexually distinct forms of the protein amelogenin in tooth enamel detectable by liquid chromatography-mass spectrometry; the protein amelogenin Y isoform is present in enamel dental tissue only in males, while amelogenin isoform X can be found in both sexes. From the point of view of archaeological, anthropological, and forensic research and applications, the reduced destruction of the methods used is essential, as well as the minimum requirements for sample size.
- Klíčová slova
- archeology, sex determination, tooth enamel,
- MeSH
- amelogenin chemie genetika metabolismus MeSH
- DNA * analýza MeSH
- lidé MeSH
- peptidy * analýza MeSH
- protein - isoformy MeSH
- reprodukovatelnost výsledků MeSH
- zubní sklovina chemie metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- amelogenin MeSH
- DNA * MeSH
- peptidy * MeSH
- protein - isoformy MeSH
An increasing number of software tools can be used in forensic anthropology to estimate a biological profile, but further studies in other populations are required for more robust validation. The present study aimed to evaluate the validity of MorphoPASSE software for sex estimation from sexually dimorphic cranial traits recorded on 3D CT models (n = 180) from three populations samples (Czech, French, and Egyptian). Two independent observers performed scoring of 4 cranial traits (2 of them bilateral) in each population sample of 30 males and 30 females. The accuracy of sex estimation using traditional posterior probability threshold (pp = 0.5) ranged from 85.6% to 88.3% and overall classification error from 14.4% to 11.7% for both observers, and corresponds to the previously published values of the method. The MorphoPASSE method is also affected by the subjectivity of the observers, as both observers show agreement in sex assignment in 83.9% of cases, regardless of the accuracy of the estimates. Applying a higher posterior probability threshold (pp 0.95) provided classification accuracy of 97.9% and 93.3% of individuals (for observer A and B respectively), minimizing the risk of error to 2.1% and 6.7%, respectively. However, sex estimation can only be applied to 54% and 66% of individuals, respectively. Our results demonstrate the validity of the MorphoPASSE software for cranial sex estimation outside the reference population. However, the achieved classification success is accompanied by a high risk of errors, the reduction of which is only possible by increasing the posterior probability threshold.
- Klíčová slova
- Forensic anthropology, MorphoPASSE software, Posterior probability threshold, Risk of error, Sex estimation,
- MeSH
- dospělí MeSH
- lebka * anatomie a histologie diagnostické zobrazování MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- počítačová rentgenová tomografie MeSH
- pravděpodobnost MeSH
- reprodukovatelnost výsledků MeSH
- software * MeSH
- soudní antropologie * metody MeSH
- určení pohlaví podle kostry * metody MeSH
- zobrazování trojrozměrné MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
- Geografické názvy
- Egypt MeSH
- Francie MeSH
Biosocial impact of facial dominance and sex-typicality is well-evidenced in various human groups. It remains unclear, though, whether perceived sex-typicality and dominance can be consistently predicted from sexually dimorphic facial features across populations. Using a combination of multidimensional Bayesian approach and geometric morphometrics, we explored associations between perceived dominance, perceived sex-typicality, measured sexual shape dimorphism, and skin colour in a European and an African population. Unlike previous studies, we investigated the effect of facial variation due to shape separately from variation due to visual cues not related to shape in natural nonmanipulated stimuli. In men, perceived masculinity was associated with perceived dominance in both populations. In European women higher perceived femininity was, surprisingly, likewise positively associated with perceived dominance. Both shape and non-shape components participate in the constitution of facial sex-typicality and dominance. Skin colour predicted perceived sex-typicality in Africans but not in Europeans. Members of each population probably use different cues to assess sex-typicality and dominance. Using our methods, we found no universal sexually dimorphic scale predicting human perception of sex-typicality and dominance. Unidimensional understanding of sex-typicality thus seems problematic and should be applied with cautions when studying perceived sex-typicality and its correlates.
- MeSH
- Bayesova věta MeSH
- černoši * MeSH
- lidé MeSH
- obličej * MeSH
- percepce MeSH
- sexuální chování MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH