Recent applications of isotope analysis to forensic anthropology

Isotope analysis has become an increasingly valuable tool in forensic anthropology case-work over the past decade. Modern-day isotopic investigations on human remains have integrated the use of multi-isotope profiles (e.g. C, N, O, H, S, Sr, and Pb) as well as iso-topic landscapes ("isoscapes") from multiple body tissues (e.g. teeth, bone, hair, and nails) to predict possible region-of-origin of unidentified human remains. Together, data from various isotope analyses provide additional lines of evidence for human identification, including a decedent's possible region-of-birth, long-term adult residence, recent travel history, and dietary choices. Here, we present the basic principles of isotope analysis and provide a brief overview of instrumentation, analytical standards, sample selection, and sample quality measures. Finally, we present case studies that reflect the diverse applications of isotope analysis to the medicolegal system before describing some future research directions. As shown herein, isotope analysis is a flexible and powerful geolocation tool that can provide new investigative leads for unidentified human remains cases.

The role of forensic anthropology in disaster victim identification(DVI):recent developments and future prospects

Forensic anthropological knowledge has been used in disaster victim identification(DVI)for over a century,but over the past decades,there have been a number of disaster events which have seen an increasing role for the forensic anthropologist.The experiences gained from some of the latest DVI operations have provided valuable lessons that have had an effect on the role and perceived value of the forensic anthropologist as part of the team managing the DVI process.This paper provides an overview of the ways in which forensic anthropologists may contribute to DVI with emphasis on how recent experiences and developments in forensic anthropology have augmented these contributions.Consequently,this paper reviews the value of forensic anthropological expertise at the disaster scene and in the mortuary,and discusses the way in which forensic anthropologists may use imaging in DVI efforts.Tissue-sampling strategies for DNA analysis,especially in the case of disasters with a large amount of fragmented remains,are also discussed.Additionally,consideration is given to the identification of survivors;the statistical basis of identification;the challenges related to some specific disaster scenarios;and education and training.Although forensic anthropologists can play a valuable role in different phases of a DVI operation,they never practice in isolation.The DVI process requires a multidisciplinary approach and,therefore,has a close collaboration with a range of forensic specialists.

Contributions of forensic anthropology to positive scientific identification:a critical Review

This review covers previous and current literature on the impact of forensic anthropologists on the positive scientific identification of human remains and aims to provide an under-standing of what information a forensic anthropologist can contribute to an investigation. Forensic anthropologists looking to identify human remains study traits of the skeleton and any orthopedic devices present. In order to obtain a positive scientific identification, evi-dence that is both sufficiently unique to the individual and comparable to available ante-mortem data from that individual must be found. The increased availability of radiographs, scans and implants in recent decades has facilitated the identification process. When these records are unavailable, other techniques, such as craniofacial superimposition and facial approximation, can be employed. While these methods may assist the identification process, they are most useful for exclusion of certain individuals and gathering leads from the public. Forensic anthropologists have heavily relied on the skull and its complexities for identifica-tion – typically focusing on the frontal sinus and other unique traits. Post-cranial remains can provide important information about bone density, possible disease and other character-istics that may also be utilized. Techniques used to positively identify individuals are not limited to medicolegal death investigations, and have been useful in other legal contexts. In the future, a team approach, utilizing all the information gathered by multiple forensic scientists–including forensic anthropologists–will most likely become more common.

Estimation of age in forensic anthropology:historical perspective and recent methodological advances

Estimation of age represents a central focus of forensic anthropological analysis of human skeletal remains and of the living. Advances registered in recent research include the topics of taphonomic impact, new anatomical areas of interest, histology, population variation, the dental pulp chamber, technology, mathematical approaches, biochemical analysis and techniques specifically targeting the living. This article reviews the historical development of age estimation methods and considers likely future directions.

Recent advancements in the analysis of bone microstructure: new dimensions in forensic anthropology

Bone is a mechanically active,three-dimensionally(3D)complex,and dynamic tissue that changes in structure over the human lifespan.Bone tissue exists and remodels in 3D and changes over time,introducing a fourth dimension.The products of the remodelling process,secondary and fragmentary osteons,have been studied substantially using traditional two-dimensional(2D)techniques.As a result,much has been learned regarding the biological information encrypted in the histomorphology of bone,yielding a wealth of information relating to skeletal structure and function.Three-dimensional imaging modalities,however,hold the potential to provide a much more comprehensive understanding of bone microarchitecture.The visualization and analysis of bone using high-resolution 3D imaging will improve current understandings of bone biology and have numerous applications in both biological anthropology and biomedicine.Through recent technological advancements,we can hone current anthropological applications of the analysis of bone microstructure and accelerate research into the third and fourth dimensional realms.This review will explore the methodological approaches used historically by anthropologists to assess cortical bone microstructure,spanning from histology to current ex vivo imaging modalities,discuss the growing capabilities of in vivo imaging,and conclude with an introduction of novel nonhistological modalities for investigating bone quality.

Recommendations for procedures related to the evidence chain of custody in forensic anthropology in Brazil

Forensic anthropologists perform specialised analysis,mainly involving skeletonised human remains,cadavers in advanced stages of decomposition,disassociated elements from the human body,and human remains in extreme carbonisation.The main objectives of the forensic anthropology expertise are human identification and assisting in determining the cause and manner of death.Estimating the time since death is also a priority for some cases,especially ones involving missing persons.This science works on individual cases,violent deaths,missing persons,mass disasters,suspected violations of human rights,and crimes against humanity.Forensic anthropological evidence is,in general,very sensitive.Thus,it is important to detail aspects relevant to the maintenance of the chain of custody at all phases of the investigation,as well as standardise the actions of the individuals involved.This aims to preserve the evidence integrity and sameness(Sameness:free translation of the Portuguese word“mesmidade”,derived from a Spanish word that does not possess a translation to Portuguese.Sameness of evidence is understood as the guarantee that the evidence under valuation(or under analysis of its probative value)is exactly and integrally the same one which was collected,corresponding,therefore,to“the same”(and not“part of”,“derived from”),safeguarding its value.Brazil Law No.13.964 of 14 December 2019 establishes and lists 10 phases related to the evidence chain of custody that must be followed.These newly introduced requirements resulted in the need for adaptation of the forensic,investigative,and legal actors involved in an investigation,and in the detailed description of the procedures for the different areas related to criminalistics,including forensic anthropology.The information provided in this article should be interpreted as recommendations,even though their non-compliance may weaken the investigative and forensic analysis processes in whole or in part.

Identification of a decedent in a 103-year-old homicide case using forensic anthropology and genetic genealogy

Anthropologists are often the custodians of long-term unidentified human remains though their positions as curators of university or museum skeletal collections.Various factors decrease the solvability of these legacy cases including the passage of time,the loss of provenience for specific cases,and lack of documentation or case records.While anthropologists can contribute important information toward identification,it is often necessary to explore novel and cross-disciplinary strategies to resolve difficult cold cases.In long cold cases,the postmortem interval,in particular,may be difficult to estimate leading to further challenges in achieving identification.Modern advances in radiocarbon bomb pulse dating,isotope analysis,and actualistic studies have contributed to positive identification of unidentified human remains in some legacy cases,but may not be available to all forensic practitioners and law enforcement from resource-poor agencies.Pooling resources,as well as collaborating with professionals outside of forensic anthropology,is a useful strategy to pursue when anthropological methods are exhausted.The case study presented here demonstrates a collaborative approach between forensic anthropologists,forensic genetic genealogists,and law enforcement in a century-old homicide.The dismembered and mummified parts of a male body were recovered in a remote cave in 1979 and again in 1991.Despite forensic anthropologists creating and updating the biological profile over the decades from recovery to present,no identification was made until the application of forensic genetic genealogy(FGG)to the case in 2019.New interpretations of bone microstructure and trauma analysis are presented for the case,alongside the historical documentation and“proof of life”evidence used by the genealogy team.A review of the FGG methods underscores the challenges in this case(e.g.significant endogamy,multiple aliases used by the victim)and the steps taken toward resolution.Ultimately,a combined anthropology and genealogy approach resulted in a confirmed identity for a man who was murdered in 1916.

Fragment analysis in forensic anthropology

Anthropological analysis of fragmentary evidence can be challenging but diverse methods allow substantial information to be gleaned.Scanning electron microscopy/energy dispersive X-ray spectroscopy enables determination if bone and/or tooth tissue is present.Protein radioimmunoassay or DNA analysis can establish the species present.Histological analysis can assist in species determination and reveal information about thermal changes.Radiocarbon analysis with special reference to the modern bomb-curve can clarify the post-mortem interval.Anthropologists should also be aware that DNA analysis not only can enable positive identification but assist in the evaluation of sex and age at death.

Nonmetric Traits in Permanent Teeth as Clues to Ethnicity in Vidarbha Subpopulation to Aid Forensic Profiling:Pilot Study

Introduction:Nonmetric dental traits have a crucial role in ethnic classification of populations that help in forensic racial identification.Many studies have demonstrated the differences in the expression and frequency of dental traits between various ethnic groups for ancestry determination in the context of forensic dental anthropology.The present study is an attempt to assess the frequency and variation in nonmetric traits for establishing ethnicity in the Vidarbha subpopulation.Aim:The aim of the study was to assess the frequency and variation of nonmetric traits in permanent teeth for establishing ethnicity in the Vidarbha subpopulation.Materials and Methods:Participants of the Vidarbha subpopulation were selected by random sampling method.Molars,premolars,and incisors were evaluated for frequency of nonmetric traits,and variations were graded according to Dentoanthropological System of State University of Arizona criteria.Descriptive statistics,Chi-square test,and Student’s t-test were used for analysis of data.Results:The most common occlusal morphology in mandibular first and second molar was 5 cusp and 4 cusp,respectively,with the“+”groove pattern.Cusp 3 and cusp 4 were observed frequently in the maxillary molars.One lingual cusp was most commonly seen in mandibular premolars show while incisors showed faint shoveling.Conclusion:Our study concludes that nonmetric traits were present and showed variation in permanent maxillary and mandibular teeth among the Vidarbha subpopulation.Cusp 5 and Cusp 4 in first and second mandibular molars,respectively,groove pattern“+”and grade 1 protostylid were the most frequent grades observed in permanent mandibular molars.One lingual cusp was most commonly seen in mandibular premolars and faint shoveling was a notable feature in incisors of this population.

A Comparative Analysis on the Histomorphometric Pattern of Various Segments of Adult Male Long Bones: Forensic Implication

Background:Human bone analysis is a useful tool in assessing and identifying skeletal remains.To make this easier,newer and modified approaches have often being documented.Aims and Objectives:The aim of this study is to analyze the histomorphometric features of various bone segments and its relevance in forensic case diagnosis.Materials and Methods:The human bones used were that of cadaveric bone samples harvested from three adult male Nigerians.The proximal,midshaft and distal segments of the femur,tibia,and humerus were utilized for the study.The bone sections were subjected to processing using Frost’s rapid manual preparation of ground sections techniques.Histomorphometric evaluation studied the number of primary osteons,secondary osteons,and osteon fragments,as well as the Haversian canal diameter(HCD).Results:The primary osteons,secondary osteons,osteon fragments,and HCD in each of the segments of the long bones show that the F values are less than the F critical for an alpha level of 0.05.This shows that there is no statistically significant(P>0.05)variation in the histomorphometric pattern for the various segments of the bones studied.Again differences in the haversian canal diameter of the various segments of the long bones shows statistically significant variation(P<0.05)among the long bones investigated.Conclusion:These findings have laid to rest the challenges with using the only available bone fragment for forensic case investigation as no notable variations exist across various segments.

Stature Estimation Using Hand and Foot Metrics among the Meena Tribal Population of the North-western Indian Region

Background:Studies on stature estimation models for North West Indian populations are limited.The present study attempts to develop stature estimation models for the Indian population using hand and foot dimensions.Materials and Methods:Hand and foot measurements of 280 individuals(140 males and 140 females)were recorded for the estimation of stature in the present study.The stature and nine hand and foot anthropometric measurements were obtained using standard methods and relevant landmarks.For bilateral and sex differences,independent and paired t-tests were used to statistically analyze the data.Results:The findings showed statistically significant sex differences(P<0.05)in stature,foot,and hand measurements.However,there were no significant bilateral differences.The Pearson correlation coefficient assessed the association between stature and hand/foot measurements.All the studied parameters in both sexes demonstrated a statistically significant(P<0.001)and strong positive correlation with stature.Males and females had the strongest correlation coefficients for right-foot length(r=0.70)and right-hand length(r=0.64),respectively.Each sex’s regression equations were calculated separately.Stature predictions were accurate to within 4.02-6.64 cm.Conclusion:Stature estimated from hand and foot measurements can help in personal identification by creating an individual’s biological profile.Morphological differences in feet and hands demonstrate the significance of developing ethnic group-specific models to determine stature.According to the study’s findings,the stature of a person belonging to the Indian subcontinent can be estimated using hands and feet for anthropological and forensic purposes.

DNA recovery and analysis from skeletal material in modern forensic contexts

The generation of a DNA profile from skeletal remains is an important part of the identifica-tion process in both mass disaster and unidentified person cases. Since bones and teeth are often the only biological materials remaining after exposure to environmental conditions, intense heat, certain traumatic events and in cases where a significant amount of time has passed since the death of the individual, the ability to purify large quantities of informative DNA from these hard tissues would be beneficial. Since sampling the hard tissues for gen-etic analysis is a destructive process, it is important to understand those environmental and intrinsic factors that contribute to DNA preservation. This will serve as a brief introduction to these topics, since skeletal sampling strategies and molecular taphonomy have been dis-cussed in depth elsewhere. Additionally advances in skeletal DNA extraction and analysis will be discussed. Currently there is great variation in the DNA isolation methods used by laboratories to purify DNA from the hard tissues;however, a standardized set of short tan-dem repeat (STR) loci is analyzed by many US laboratories to allow for comparisons across samples and jurisdictions. Recent advances have allowed for the generation of DNA profiles from smaller quantities of template DNA and have expanded the number of loci analyzed for greater discriminatory power and predictions regarding the geographic ancestry and phenotype of the individual. Finally, utilizing databases and expanding the number of com-parison samples will be discussed in light of their role in the identification process.

Use of deep learning in forensic sex estimation of virtual pelvic models from the Han population

Accurate sex estimation is crucial to determine the identity of human skeletal remains effectively.Here,we developed convolutional neural network(CNN)models for sex estimation on virtual hemi-pelvic regions,including the ventral pubis(VP),dorsal pubis(DP),greater sciatic notch(GSN),pelvic inlet(PI),ischium,and acetabulum from the Han population and compared these models with two experienced forensic anthropologists using morphological methods.A Computed Tomography(CT)dataset of 862 individuals was divided into the subgroups of training,validation,and testing,respectively.The CT-based virtual hemi-pelvises from the training and validation groups were used to calibrate sex estimation models;and then a testing dataset was used to evaluate the performance of the trained models and two human experts on the sex estimation of specific pelvic regions in terms of overall accuracy,sensitivity,specificity,F1 score,and receiver operating characteristic(ROC)curve.Except for the ischium and acetabulum,the CNN models trained with the VP,DP,GSN,and PI images achieved excellent results with all the prediction metrics over 0.9.All accuracies were superior to those of the two forensic anthropologists in the independent testing.Notably,the heatmap results confirmed that the trained CNN models were focused on traditional sexual anatomic traits for sex classification.This study demonstrates the potential of AI techniques based on the radiological dataset in sex estimation of virtual pelvic models.The excellent sex estimation performance obtained by the CNN models indicates that this method is valuable to proceed with in prospective forensic trials.

Humanitarian action in academic institutions:a case study in the ethical stewardship of unidentified forensic cases

Forensic anthropologists are often responsible for the management of long-term unidentified individuals.Others have contextualised these decedents—many of whom likely belonged to socially,politically,and/or economically marginalised groups in life—as part of a larger identification crisis in the US.However,there has been little discussion surrounding how this humanitarian crisis has manifested in academic institutions,where anthropologists often provide medicolegal consultation and act as long-term stewards of the unidentified.The Identification&Repatriation Initiative was created at the Forensic Anthropology Centre at Texas State University(FACTS)to recognise and investigate unidentified human remains in long-term storage.Our paper outlines common challenges that were encountered during our initial reassessment of unidentified cases at FACTS,emphasising the detrimental impacts of inconsistent procedures,loss of context,and case fatigue.It is likely that other academic institutions face similar challenges,and by highlighting these issues we hope to help initiate a larger conversation concerning ethical stewardship of human remains in these settings.By incorporating humanitarian perspectives into forensic casework,anthropologists in academia can better advocate for the long-term unidentified.

Gaining community entry with survivors for forensic human rights and humanitarian intervention

As forensic humanitarian and forensic human rights anthropology has continued to evolve,an ongoing concern in the field is meaningful engagement with survivors and the imperative to do no harm.For forensic anthropologists attempting to engage in grassroots forensic intervention,unaffiliated with an international investigation,means for effectively accessing and engaging communities has not been widely discussed.Here,forensic anthropologists draw on multiple,cross-cultural contexts to discuss methods and techniques for introducing forensic partnerships to communities.To do this,the scientist must consider their positionality as well as that of the stakeholders,develop effective local relationships,and consider a community-grounded approach.This paper argues that drawing on broader cultural anthropological training,ultimately informs one’s ability to gain entry into at-risk and vulnerable communities while minimizing harm.To illustrate this point,examples are drawn from Canada,Uganda,Cyprus,and Somaliland.

Contributions of anatomy to forensic sex estimation: focus on head and neck bones

This study sought to provide an up-to-date review of the importance of anatomy to human identification,focusing on the usefulness of anatomical knowledge about the head and neck bones and teeth to sex estimation in routine forensic anthropology methods.A detailed search of osteology applications in forensic sex estimation was conducted through the electronic databases for the 10 years prior to July 2020.Relevant articles and classic literature on the subject were gathered and outlined in this review.Among the available literature,several metric analyses showed accuracy superior to 80%in sexual diagnosis.Angles measured from the inclination of glabellae and analysis of the external frontal bone surface through three-dimensional computer-aided design emerge as reliable cranial indexes for sex estimation.in the mandible,the condylar and coronoid height,bigonial width,and condylion-gonion distance express significant sexual dimorphism.Measurements of the canine are the best option for sex estimation using teeth,as well as the thickness of the dentine or enamel of incisors.The axis vertebra surpasses other neck bones for sex estimation due to its atypical shape and the presence of the odontoid process.Metric analyses based on anatomy can provide reliable accuracy in sexual diagnosis.Adequate training and anatomical knowledge can reduce bias and interobserver differences,and the use of three-dimensional models and computed tomography images can enhance the accuracy of these methods for sex estimation.However,every method should be validated before being applied to a different population.

Epidemio-toxicological profile of suicide cases:analysis from a forensic unit in Brazil

The suicide phenomenon involves complex interactions between psychological,biological,cultural and socio-environmental factors.This study aimed to assess the epidemiological and toxicological profiles of officially confirmed suicide victims.Aretrospective study was performed using autopsy reports,forensic anthropology examinations and police summaries of all suicide cases that underwent toxicological analysis at an Official Forensic Laboratory(Minas Gerais,Brazil)in 1 year.The sample set was composed of 351 suicide victims,predominantly men(70.32%),most of them were adults between 31 and 64 years old(62.11%),with mixed skin colour(48.89%)and low educational level(66.44%).The most common suicide method was hanging(57.79%),followed by intoxication(30.45%).Most victims presented positive toxicological results(56.41%),especially for the presence of medicines(37.6%),illicit drugs(36.3%)and pesticides(26.1%).Our study corroborated previous data that most suicide victims have low educational levels.The most common toxicological findings were medicines,especially prescription drugs,followed by illicit drugs and pesticides.We hope this study contributes to reflections and planning of preventive suicide programmes,considering the described profiles of victims.

Personal identification and missing persons initiatives in Santa Catarina state,Brazil:forensic perspectives from 2019 to 2021

Santa Catarina is a small,developed,and relatively safe state in South Brazil.Despite having positive social economic indicators,it still faces multiple challenges regarding forensic practices for personal identification.The objective of this paper is to discuss the recent advances and current challenges in the region,from the perspectives of anthropological and dental postmortem human identification,missing persons,and disaster victim identification(DVI)from 2019 to 2021.The recent creation of a Forensic Anthropology Sector(SAF)in the state’s official forensic institution(Polícia Científica-PCI)has significantly improved identification of unidentified remains and optimised resources available for DNA analysis.However,SAF is still quite understaffed,which negatively affects the recovery of skeletal material,its preparation,and the time needed for filing reports.Santa Catarina has passed legislation for missing persons in 2015,4 years prior to the sanction of federal laws implementing the national policy for the disappeared.Nonetheless,a lack of integration between stakeholders remains a problem that PCI has tried to circumvent with the Conecta Programme,a multidisciplinary and integrated initiative between families of the missing persons,police agencies,and the Public Ministry.The programme aims to collect not only reference DNA samples,but also relevant anthropological and dental data.It also offers facial progression services in cases of disappearances that occurred many years ago.Despite a history of disasters in the state,PCI still needs to implement international DVI standards at an institutional level.Recent training on Phase 1 DVI procedures,integrated with other responding institutions,indicates better preparation for future disasters.There are many challenges ahead for Santa Catarina’s forensic institution and professionals that have yet to be addressed,but the overall situation on routine personal identification,missing persons initiatives,and DVI has improved over the last 2 years.

Virtual anthropology:a preliminary test of macroscopic observation versus 3D surface scans and computed tomography(CT)scans

Virtual anthropology(VA)is based on applying anthropological methods currently used to analyse bones to 3D models of human remains.While great advances have been made in this endeavour in the past decade,several interrogations concerning how reliable these models are and what their proper use should be remain unanswered.In this research,a fundamental assumption of VA has been investigated:if the way we perceive and apply an anthropological method is truly similar when looking at bones macroscopically and through various 3D media.In order to answer,10 skulls of known age and sex were scanned using a computed tomography(CT)scanner and a 3D surface scanner.Two observers separately applied a defined staging method to eight suture sites on these skulls,first looking at the bone macroscopically,then at the 3D surface scan,and finally on the CT scan.Two rounds of observation were carried out by each observer.Intra-and inter-observer error were evaluated,and two sample t-tests used to evaluate if the different types of medium used yielded significantly different observations.The results show a high degree of inter-observer error,and that data obtained from 3D surface scans differ from macroscopic observation(confidence level 95%,P≤0.05).CT scans,in these settings,yielded results comparable to those obtained through macroscopic observations.These results offer many possibilities for future research,including indications on the kind of anthropological methods and anatomical landmarks that might be reliably transferable to the virtual environment.All current methods used in traditional anthropology should be tested,and if they prove unreliable,new techniques to analyse bones from virtual models should be developed.

Virtual anthropology-a brief review of the literature and history of computed tomography

Computed tomography(CT)has influenced numerous fields since its inception in the 1970s.The field of palaeoanthropology significantly benefited from this efficient and non-invasive medium in terms of the conservation,reconstruction and analysis of fossil human remains.Over the past decade,there has been a steady increase in the number of forensic anthropological studies incorporating virtual osteological analyses.Because of the increasing importance of these modern cross-sectional imaging techniques and the requirement for standardized parameters in forensic science,we deemed it important to outline the history and development of CT applications in these related academic areas.The present paper outlines the history of“virtual anthropology”and osteological multi-detector CT in the context of palaeoanthropology and forensic anthropology.