Documented Skeletal Collection

The successful identification of the deceased is vital to the progress of any forensic investigation. One of the principal biological traits to be established from skeletal remains is the sex of the individual. This becomes more difficult if only parts of a skeleton are found or if the bones are compromised by physical insults such as fire, explosions or violence. The basal region of the occipital bone is covered by a large volume of soft tissue and is therefore in a relatively well-protected anatomical position, and as such, classification of sex using the occipital bone may prove useful in cases of significantly disrupted remains. The aim of this paper is to evaluate manually recorded morphometric variables of the region of the foramen magnum using both discriminant function analysis and linear regression. The skulls utilised in this study were selected from the eighteenth to nineteenth century documented skeletal collection of St. Bride's Church, Fleet Street, London. Adult human skulls n = 158 (males 82/females 76) were measured to derive statistical functions. The results demonstrated that significant sexual dimorphism is present in the cranial base of the St. Bride's material. The correctly classified crania within this population ranged from 65.8% for univariate functions to 70.3% for multivariate functions within the cranial sample. Males were correctly classified at 70.7% and females at 69.7% using multivariate functions. The linear regression equations predicted sex in the cranial sample correctly for 76% of the males and 70% for the females using different variables; however, overall highest correct prediction percentage was only 68%. Cross-validation brought the percentage down in some cases, but it was concluded that, overall, the expression of sexual dimorphism in the foramen magnum region within the St. Bride's population is significantly demonstrable, and therefore, this area of the skull should be considered useful in the identification of sex.

Vault sutures have proven their low reliability for estimating age at death in individual forensic science cases. We broke down the palatine sutures of 134 skulls (with known sex and age at time of death) into 15 subparts and 5 stages of fusion to obtain a mean coefficient of obliteration (Cp) which was then linked to five age classes. We completed this study with multiple regression equations of total palatine suture scores. We compared our results with those obtained using the Mann method on the one hand and classically segmented and scored ectocranial suture age determination methods on the other. Palatine sutures generally do not estimate age at death any better than cranial vault sutures. Despite the partly subjective aspect of suture study, palatine suture observation contributes additional information to age-range estimation, especially in old and very old subjects where other methods lose their effectiveness.

Metric variables did not replicate the accuracy values originally obtained by Luna and co-workers. Otherwise, the evaluation of morphological variables proposed by the authors yielded promising results as a reliable sexing technique for individuals who died before puberty. This method should be further refined through additional testing on different populations in order to improve its validity and reliability. Future research should focus on the development of more clearly identifiable landmarks on the auricular surface and should provide a more detailed description of the dimorphic features.

The Forensic Anthropology Center at Texas State (FACTS) was established in 2008 in San Marcos, TX with the mission to advance forensic science and anthropology through world-class education, research, and outreach. An important part of FACTS’ mission is to make available to the greater scientific community the individuals that have been donated to the FACTS Willed Body Donation Program. At the time of this publication, the Willed Body Donation Program consists of N=282 individuals and is growing at a rate of approximately 70 individuals per year. Each individual has a detailed life history, living photographs, medical records, tissue samples, and blood samples available to researchers. Demographic information includes: 171 males, 111 females, 258 European Americans, 14 African Americans, and 10 Hispanics. The mean age of the individuals is 65.3 years with a range of 26 weeks to 102 years. After each individual is placed in our 26-acre outdoor decomposition research laboratory, the skeletal remains are curated into the Texas State University Donated Skeletal Collection (TXSTDSC) in perpetuity. The TXSTDSC has 100+ individuals curated with complete biological profiles, standard cranial and postcranial measurements, pathological conditions, and anomalies available for study to researchers at all levels. In addition to our TXSTDSC, FACTS also has state of the art technology available including micro-CT, digital radiography, high-resolution 3D imagery, 3D landmark data collection, 3D printing, and bone histology lab. These technologies combined with an in-house documented skeletal collection provide unique and important opportunities for anthropologists in all sub-disciplines looking to explore new skeletal collections.