The present research examined the effects that the variables of burial depth and presence of a plastic covering material had on the decomposition rate of fetal remains. The experimental sample consisted of fetal pigs (Sus scrofa) as a substitute for fetal human remains. The general size and bone composition of fetal pigs are comparable to those of fetal humans. The decomposition of the fetal pigs remains was observed in four independent variable groups: 20 cm unwrapped, 20 cm wrapped, 60 cm unwrapped, and 60 cm wrapped, per time period. The author hypothesized that the rate of decay would be slower for wrapped remains or for remains at a greater burial depth. The results of the two different burial depths and of the wrapped versus unwrapped groups was analyzed to determine the effects of those variables on the rate of decomposition. Analysis of these remains consisted of quantitative data, including pre-burial and post-burial mass comparison as well as the Total Body Score. It was found that wrapping was a significant influencer of mass loss with a p value of 0.0298 but not for the Total Body Score with a p value of 0.17565, while burial depth did not have a significant effect on either mass loss nor Total Body Score with a p value of 0.1956 and 0.08969, respectively.

No description available.

Skeletal remains exposed to an outdoor context are prone to post-mortem damage and fragmentation, making skeletal analysis difficult for the anthropologist. Research on ancestry and sex from isolated fragments of the cranium is necessary to improve identification of fragmented remains. The zygoma has proven to be more durable post skeletonization than other cranial bones, making research relevant into variation within the zygoma. Whilst the shape of the zygoma has been studied in a South African population using morphological, metric and geometric morphometric techniques, these studies did not include Indian South Africans. The Indian South African population comprises 2.6% of the total population but make up a larger proportion of the population in certain areas. For example, Indian South Africans comprise 7.4% of the population in Kwa-Zulu Natal and 2.9% in Gauteng. More specifically, Indian South Africans make up to 60% of the population in the suburb of Chatsworth with a further 91% of the population in sub-area of Arena Park, and 80% of the population in the Laudium suburb of Gauteng. Therefore, Indian South Africans must be included in anthropological studies attempting ancestry classifications. The purpose of the study was to assess the shape variation and projection of the zygoma attributable to sexual dimorphism and ancestral variation among South Africans, including Indian South Africans, using a geometric morphometric approach. A sample of 400 three-dimensionally (3D) reconstructed models from head CT scans of black, coloured, white, and Indian South Africans were used with an equal sex and ancestry distribution. Eleven landmarks previously described in the literature were used for the analysis. Each landmark was used to depict the most prominent points on the outline of the zygoma. Additionally, semi-landmarks were placed along the curves of the zygoma. The landmarks and semi-landmarks were tested for observer repeatability and reliability using dispersion analysis and revealed that all landmarks were repeatable. Procrustes ANOVA revealed significant differences among the population groups and between the sexes for all population groups, except between coloured South African males and females. A pairwise post-hoc test revealed that white and Indian South Africans had the most similarities except for males, where coloured and Indian South Africans had the most similarities for landmarks. Three interlandmark distances were created to assess the zygoma’s projection. The ANOVA for the projection of the zygoma revealed significant differences for both sex and ancestry except for white South African males and females and males overall for the zygomaticomaxillary length. The zygomaticomaxillary length (ZML) is defined as the maximum distance between the landmarks zygoorbitale and zygomaxilare. No significant differences were noted for female South Africans for the Superior Zygomatic Length which, is a measure of the maximum length of the superior margin of the zygoma (between porion and zygoorbitale; PorZygool). Further analysis of the zygoma’s projection involved creating angles between the interlandmark distances. The ANOVA for the angles of projection revealed significant differences between sexes and populations, except for white and Indian South African males and females at Angle1 (Angle at the intersection of ZML and PorZygoml) and Angle3 (the angle at the intersection of PorZygool and PorZygoml) and black, coloured and Indian South African males and females at Angle2 (the angle at the intersection of ZML and PorZygool). The large amount of overlap amongst ancestry groups demonstrated substantial group similarities; however, differences were noted at the zygomaxillary, zygomaticotemporal and frontomalar sutures. Overlap was also present between males and females, but on average, males were larger than females. Differences, such as a more inferior placement of the zygoorbitale landmark were noted at the inferior margin of the orbit specifically in females. Differences were also noted at the inferior margin of the orbit across all groups. Discriminant functions were created to assess the classifying ability of the shape of the zygoma. Results revealed low accuracies for ancestry classification for the shape and projection of the zygoma. However, higher accuracies were noted for sex classification for the shape and projection of the zygoma. While results demonstrate shape variation of the zygoma, the classifying ability of the zygoma is precarious at best, and the use of the zygoma in a forensic context may not be an option. However, the differences observed can be taken into consideration during medical procedures such as zygomatic and infraorbital implants. Although landmark placements were reliable and repeatable, further analysis of the zygoma using a semi-automatic surface registration method along with different imaging techniques (MicroCT and CBCT scans) may assist in the data collection procedure and may potentially increase the accuracy of the results. Furthermore, the results of the current study highlight the need for the assessment of the effects of diet, climate, age, edentulism and symmetry on the shape of the zygoma. / Dissertation (MSc (Anatomy))--University of Pretoria, 2020. / National Research Foundation (NRF) / Anatomy / MSc (Anatomy) / Unrestricted

Age estimation techniques have utilized cranial suture closure, the sternal rib ends, the auricular surface, and the pubic symphysis, each with varying degrees of success. Although recent research has attempted to advance methodologies for age estimation, little progress has been made in discerning forensic age ranges that are beyond general estimates, especially in the old adult (50+) cohort. Since the accuracy of current aging methods decreases as chronological age increases, degenerative changes within the skeleton could potentially yield useful data for establishing and narrowing age estimates for older individuals, especially where only limited or fragmentary remains are recovered. The purpose of the present study was to conduct a visual examination of joint surfaces typically found to be affected by osteoarthritis (OA) by the fourth decade of life using a modified version of the OA scoring system proposed by Buikstra and Ubelaker (1994). According to archaeological, forensic, and clinical research, OA is most commonly found in the shoulder, hip, and knee, making these joints ideal for use in the present study. Within these three joints, ten osseous surfaces were examined: the acromial facet of the scapula, the glenoid fossa of the scapula, the lateral clavicle, the humeral head, the acetabulum of the os coxa, the femoral head, the medial and lateral femoral condyles, and the medial and lateral facets of the patella. Evidence of lipping, surface porosity, osteophyte formation, and eburnation were recorded on an ordinal scale, along with the percentage of the joint surface that was covered by each of the aforementioned traits. The data gathered from this examination were used to create a composite scoring system for age–at–death estimation using a modern North American sample of 206 White individuals from the W. M. Bass Donated Skeletal Collection and the Boston University Donated Osteological Collection. Significance testing indicated that sex differences were not present in the current analysis. A paired-sample t–test determined that the sample was affected with statistically significant levels of bilateral asymmetry. In addition, the current method is affected by low levels of intraobserver error, with only 5% of the sample being affected. Pearson's and Spearman's correlation coefficient were used to examine the relationship between a selected variable and age. The results of the present study indicate that OA has a positive correlation with age, although some joints show weaker associations than others. The right shoulder showed the highest correlation with age (r = 0.776, rs = 0.769; p < 0.01), followed closely by the left shoulder (r = 0.753, rs = 0.753; p < 0.01). The next highest correlation with age was observed for the left knee (r = 0.545, rs = 0.568; p < 0.01), followed by the right knee (r = 0.459, rs = 0.459; p < 0.01). The lowest correlation was observed in the left hip (r = 0.414, rs = 0.377; p < 0.01) and right hip (r = 0.476, rs = 0.377; p < 0.01). Data from multiple joint surfaces were combined for statistical analysis to create composite variables for each joint. The composite variables are combinations of traits for each joint that stepwise regression demonstrated as the best indictors for narrowing prediction intervals. This created a series of composite scores for the left shoulder, right shoulder, left hip, right hip, left knee and right knee. Individual prediction intervals at the 90% confidence interval were generated to create age ranges for each composite score. The mean age and frequency of each composite score was also recorded. This multifactorial approach demonstrated that the left and right shoulders provided the narrowest prediction intervals and also possessed the highest predictive power for estimating age-at-death. Relative predictive power was determined using R^2. The R^2 value for the right shoulder was the highest at 0.603, followed closely by the left shoulder with an R^2 value of 0.567. The R^2 value for all remaining variables was less than 0.3, indicating weak predictive power. The results of the present study were then compared to the four traditional macroscopic aging techniques: suture closure, morphology of the sternal rib ends, morphology of the auricular surface and the pubic symphysis. Sample distribution, correlation data, derived age ranges and error rates were compared between previous research and the results of the present study. All age estimation techniques demonstrated a positive correlation with age. Age ranges that were derived using Bayesian statistics or individual prediction intervals are more accurate at predicting actual age than those that were generated using confidence intervals of the mean, which provide information for mean age rather than actual age. In addition, the relationship between bone density and survivability of elements is discussed. It was determined that the skeletal elements utilized in traditional macroscopic aging are prone to breakage and loss based on their bone mineral density and location within the skeleton. In contrast, the proposed method utilized areas of the skeleton which are not typically examined for aging yet are likely to survive destruction from common taphonomic forces, making the use of OA in fragmentary or damaged contexts possible. Future research is needed to address the effects of ancestral variation and interobserver on the proposed method.

This research examined the behavior of avian scavenger bone dispersal in a New England environment. The furthest distance that avian species can carry bone elements can be used by search investigators by providing possible distances maximum dispersal. The sizes of bones dispersed by avian species provides context on how bone elements differing in size are transported from the initial site of deposition. The project utilized two locations with elements of varying sizes (large, intermediate, and small) with tracking tags attached to determine the distance and pattern of scavenger displacement. Scavenging was also recorded with motion-sensing game cameras that allowed for differentiation between which species scavenged on which elements, allowing for the distance carried to be associated with individual species. The most common avian scavengers were the northern cardinal (Cardinalis cardinalis), downy woodpecker (Dryobates pubescens), and blue jay (Cyanocitta cristata). The furthest element that was displaced and recovered was a pig rib approximately 62 meters from its initial placement location and it was moved by a crow (Corvus brachyrhynchos). The second furthest element displaced was a pig rib moved approximately 41.5 meters by a Cooper’s hawk (Accipiter cooperii). In addition, six other elements were removed from the platform by birds and not recovered due to possible displacement outside of the search radius and tracking application radius. Overall, 55.0% of elements were recovered within 1 meter of their initial placement location. For elements dispersed under 1 m, Rayleigh z-statistical tests (z =1.328; α = 0.05) for the site location in a wooded area indicated that directionality was not statistically significant, while the location in the wetlands was determined to be statistically significant (z = 20.656; α = 0.05). In addition, a Watson’s U2 Two-Sample Test of Homogeneity (U2 = 0.374) revealed the two groups of average directions are significantly different at α = 0.05. This indicates a difference in direction of displacement between the platforms. For Platform 1 (forested location), the results of the Mann-Whitney U-Test (z = -2.638) indicated that the distances of displacement between the spring and summer seasons are significantly different between the two seasons at α = 0.05. For Platform 2 (wetland location), the results of the Mann-Whitney U-Test (z = -0.859) indicate the distances of displacement between the two seasons were not significantly different between the two seasons at the α = 0.05 value. In addition, Kruskal-Wallis H tests revealed that there was no statistically significant difference between the platform location and the number of site visits for the majority of species. Only two species, cardinals (z = -2.04; α = 0.05) and song sparrows (z = -2.208; α = 0.05), were determined to have a statistically significant difference between the location and the number of site visits.

No description available.

With the evolution of forensic technology, methods for positive identification are vast and accurate. These methods allow for a corpse to be identified at almost any point of decomposition. The new technology and new methodology has led to a more creative and resourceful criminal. Although few cases have been documented where chemicals are the mode of disposal, this method provides a seemingly fool proof and effective approach to disposal. Several household chemicals contain harmful agents that when used may result in the masking of identity. The purpose of this study is to indicate which chemicals can be used in order to erode or dissolve the tissues making up the dentition and bone. Four chemicals, potassium hydroxide, sodium hydroxide, muriatic acid (hydrochloric acid) and sulfuric acid were chosen and tested on teeth and bone. The dentition and bone were exposed for a period of eight hours. Measurements including mass and caliper measurements were obtained at two-hour intervals. Of the common chemicals tested, muriatic acid (hydrochloric acid) was the most effective for destroying the tissues.

Societal knowledge about issues faced by transgender and gender-diverse individuals has increased; however, the field of forensic anthropology has struggled to keep abreast with ever-evolving perceptions of sex and gender. Specifically, forensic anthropology lacks a codified approach to identifying transgender decedents due to binary assigned sex estimation methods that lack a biocultural approach and divergent perspectives on the role of gender. Using an anonymous survey of forensic anthropologists (n=130), the present research explores the processes of biological profile deployment in forensic casework, along with current perspectives on sex and gender and associated methods, language, and reporting. Regarding the role of gender in casework, most (51.5%) believe identifying gender improves the odds of identification, and many (40.8%) would include such information in a forensic anthropological report, with 59.0% uncertain about testifying to gender. Additionally, 55.4% of respondents report that skeletal sex estimation does not represent a decedent’s gender, and most would cite signs of gender-affirming surgery (59.2%) or material evidence (47.7%) for use in reporting gender despite uncertainties about Daubert compliance (38.5%). Regarding terminology, respondents prefer “sex” (52.3%) or “biological sex” (34.6%) over other arguably more apt descriptors such as “assigned sex” (19.2%). While forensic anthropologists acknowledge the need for clarity in gender-inclusive definitions and mostly maintain that skeletal sex is not equivalent to gender, further studies for a truly biocultural forensic anthropology should focus on the role of sequential evidentiary unmasking and material evidence alongside assigned skeletal sex analyses.

The present research examined whether the innominate acted as contextual information which resulted in a skewed scoring of skull morphological sex traits and pairs overall (both innominate and skull). Survey participants first assessed the sex of an innominate, then assessed the sex of a skull, using methods standard in the field. The sex of ten skulls and associated innominates, which served as contextual elements to introduce bias, were assessed in two surveys by 22 participants total. Male and female innominates and skulls were mixed and matched to test bias, though it was implied to participants that the paired elements were from the same individual. No significant bias was seen on the level of the skull. However, significant shifts in scores were seen on the level of the overall pair in three out of the five studied, indicating that the sex of the innominate was privileged over that of the skull. This is considered standard procedure in the field as the innominate is more reliable for sex estimation; thus, the findings of the present study are inconsistent with cognitive bias. However, the present study raises questions about the utility of the skull in the estimation of sex in human skeletal remains. While the innominate may be more reliable in sex estimation when both elements are present, this may lead to inattention to valuable information presented by the skull in particular contexts such as commingled burials.

Among the numerous taphonomic influences that can impact biological remains, agricultural activity has one of the most widespread effects. The present research examines the impacts of agricultural activities on buried skeletal remains, both in archaeological and medicolegal contexts. Juvenile pig (Sus scrofa) skeletons were utilized to simulate buried juvenile human aged 3 to 5 years to test the influence of original burial depths and different plowing intervals on the dispersal and the degree of damage caused by an offset disk plow. Ten juvenile pig skeletons were buried in relatively anatomical position, five at a bottom depth of 15 cmbs (cm below the surface) and five at 22 cmbs. They were subjected to different intervals of plowing with one burial at each depth subjected to a single, three, five, seven, or ten plow passes. The disturbed area was surveyed for surface material, and the plow furrows were excavated in 1 m by 1 m units. The excavated soil was screened using a ¼" mesh screen, except for two burials that were screened using a nested ¼" and ⅛" mesh screen to test the differences in recovery between the two screen sizes. The recovered skeletal material was inventoried and assessed for damage. The results of this research showed that while original burial depth had some effect on distribution of bone and the degree to which bone was damaged, the relationship was not statistically significant. The number of plowing intervals did have a significant effect on the distribution and degree of damage. The damage caused to bone by the offset disk plow would be distinguishable from perimortem trauma in dry bone. Comparison of the recovery rates of ¼" and ⅛" mesh found that ⅛" contributed to a higher recovery of juvenile remains at least 3 to 5 years of age in soil with a high gravel content.