Exercises in ethically engaged work in biological anthropology.

An ethical paradigm shift currently taking place within biological anthropology is pushing scholars to envisage and develop paths toward more ethical futures. Drawing from case studies in our own teaching, research, and fieldwork experience, we reflect on the complex, diverse, and dynamic nature of ethical considerations in our field. We discuss the acquisition and institutional narrative of a human osteological teaching collection at the University of Louisville as an embodiment of structural apathy turned structural violence, and the need for professional guidance in the potential retirement of deceased individuals from our classrooms. In documented collections (i.e., the Robert J. Terry Collection), we share our process and scholarly reemphasis of the humanity of a deceased individual through contextualized analysis (i.e., osteobiography and archival history) and postmortem agentive acts. Lastly, we present an archeological site in the U.S. Virgin Islands, which poses ethical concerns as biocultural bioarcheologists and archeologists attempt to negotiate the possible wishes of the deceased with the cultural value of reconstructing the community's otherwise undocumented past, all amidst the immediate threat of anthropogenic climate change. We offer these exercises and discussion in ethically engaged projects transparently and with an overarching admission that none are models for replication. Rather, at various stages in our careers and engagement with ethics, we acknowledge that progress is worthwhile, albeit challenging, and that proceeding forward collectively as biological anthropologists should be deliberate, reflexive, and compassionate for deceased individuals and their descendant communities, as well as among and between colleagues.

Searching for a relationship between the elemental composition of archaeological bones and the occurrence of caries.

BACKGROUND: Although the macroscopic assessment of dental caries and the assessment of bone elemental composition are quite different, efforts can be made to identify commonalities in the assessment of health and nutritional quality. Both indicators are correlated with dietary habits and are dependent on taphonomic processes occurring in the postmortem substrate. However, teeth exhibit structural resilience of their hard tissues to adverse environmental factors. OBJECTIVES: The aim of the study was to establish a correlation between the elemental composition of bones and the presence of carious lesions. MATERIAL AND METHODS: The study material consisted of the following skeletal parts: 161 permanent teeth from 36 individuals and bridge fragments of 36 ribs. The presence of caries was assessed visually using a modified International Caries Detection & Assessment System (ICDAS II) scale. The rib samples were subjected to elemental analysis (zinc (Zn), iron (Fe), magnesium (Mg), calcium (Ca), phosphorus (P), strontium (Sr), barium (Ba)) using spectroscopic methods. RESULTS: The odontological and chemical analyses did not reveal any statistically significant relationships between the Ca/P diagenesis index and dental features. Postmortem tooth loss showed a weak correlation with the diagenesis index. CONCLUSIONS: Discoloration, cracks and flaking of the dental crown surfaces may be associated with the intensity of Ca/P diagenesis. However, no significant correlation was found between these phenomena. Among other elements, only Zn levels exhibited a correlation with the caries index.

Archaeology meets environmental genomics: implementing sedaDNA in the study of the human past.

Sedimentary ancient DNA (sedaDNA) has become one of the standard applications in the field of paleogenomics in recent years. It has been used for paleoenvironmental reconstructions, detecting the presence of prehistoric species in the absence of macro remains and even investigating the evolutionary history of a few species. However, its application in archaeology has been limited and primarily focused on humans. This article argues that sedaDNA holds significant potential in addressing key archaeological questions concerning the origins, lifestyles, and environments of past human populations. Our aim is to facilitate the integration of sedaDNA into the standard workflows in archaeology as a transformative tool, thereby unleashing its full potential for studying the human past. Ultimately, we not only underscore the challenges inherent in the sedaDNA field but also provide a research agenda for essential enhancements needed for implementing sedaDNA into the archaeological workflow.

Investigating femoral growth disruption in subadults from the 10th-13th century St. Étienne cemetery of Toulouse, France.

OBJECTIVES: The skeleton embodies an individual's environment and lived experiences. Studying childhood growth disruption can, therefore, aid in understanding the experiences of children in the past. This study evaluates growth disruption in a medieval Toulousian subadult sample to explore factors that may have influenced childhood growth and mortality at this site and to assess the utility of Harris line (HL) interpretations in bioarchaeology. MATERIALS AND METHODS: Femoral growth disruption was assessed in n = 71 subadults (0.125-12.42 years) from the 10th-13th century St. Étienne cemetery of Toulouse, France, using femoral length, total area, cortical area, and relative cortical area. Femoral radiographs were assessed for HLs. To determine the prevalence of growth disruption, z-scores were calculated using data from the Denver growth study. RESULTS: The majority of subadults in this sample suffered from femoral growth disruption. Young children (1.0-3.99 years) were the most affected, with >65% experiencing reduced appositional growth and linear growth stunting at time-of-death. Additionally, while many individuals presented with observable HLs, linear and appositional growth did not significantly differ between individuals with and without HLs. DISCUSSION: Maternal malnutrition and inadequate complementary feeding practices likely contributed to the high prevalence of growth disruption among the youngest individuals in the study. The older children and adolescents buried at St. Étienne experienced an amelioration in growth deficits, indicating an improvement in nutrition and/or disease load. The results of this study suggest that more consideration is required when interpreting the presence/absence of HLs, and that studies assessing HLs may benefit from using a more individualistic approach.

Assessing the existence of the male-female health-survival paradox in the past: Dental caries in medieval London.

OBJECTIVES: This study seeks to identify signals of the male-female health-survival paradox in medieval London. MATERIALS AND METHODS: This study uses skeletal data on age, sex, dental caries (n = 592) and antemortem tooth loss (n = 819) from adult individuals from medieval London cemeteries (c. 1200-1540 CE). The association between age and dental caries was assessed using binary logistic regression. The associations among age, time period (pre- vs. post-Black Death), oral biomarker (dental caries or antemortem tooth loss), and sex were tested using hierarchical log-linear analysis. RESULTS: The analyses reveal significantly higher odds of dental caries with increasing adult ages, more older adults after the Black Death, different age distributions of dental caries between the sexes, and a greater decrease in the prevalence of dental caries for females after the Black Death. These results appear not to be an artifact of trends in AMTL. However, this study does not yield evidence suggesting that females experienced both a survival advantage and a decline in oral health at late adult ages after the Black Death relative to males. CONCLUSIONS: These results do not provide evidence of the existence of a male-female health-survival paradox, but they do corroborate existing evidence of improvements in health in general in the aftermath of the Black Death. The decreased prevalence of dental caries after the Black Death may reflect dietary improvements or the effects of selective mortality during the epidemic.

Ethical challenges in the bioanthropological and biomedical investigation of Sicilian mummies-Past experience and future pathways.

This article presents a multidisciplinary approach adopted in the Sicily mummy project, highlighting unique challenges and major ethical concerns inherent to the scientific study, conservation, and presentation of these mummies. Recognizing mummies as a distinct category of human remains, this paper argues for the development and application of specialized guidelines that address the intricate balance between scientific inquiry and respect for the cultural, religious, and mortuary practices that characterize the cultural context, in this case of Sicily. Through a transparent and collaborative dialogue among all stakeholders-including curators, clergy, scientists, and government officials-the project ensures the preservation of the mummies' dignity within their sacred spaces. The critical role of biological anthropologists is emphasized, alongside the contributions of clinical radiologists, pathologists, and qualified restorers, in constructing a comprehensive understanding of the mummies' biocultural significance. The paper advocates for a bioarchaeological strategy that advances scientific knowledge while safeguarding the mummies and respecting living communities. Additionally, we call for ethical rigor in scholarly publications and suggest future actions to protect this invaluable heritage. This approach not only preserves the dignity and integrity of the mummified remains but also enriches our understanding of past human societies.

Temporal pattern of dental caries at the western flank of the Central Plateau of Iran, c. 2700 BCE - 1600 CE.

OBJECTIVE: To analyze the overall frequency and inter-tooth patterns of caries in three populations from ancient cemeteries located along the western border of the Central Iranian Plateau as a means to explore whether the populations of Iran had greater access to fermentable sugars after the establishment of the great empires. MATERIALS: Dental collections from Kafarved-Varzaneh (Early Bronze Age, MNI=66), Estark-Joshaqan (Iron Age, MNI=57), Tappeh Poustchi (Timurid and Safavid Period, MNI=34), together with comparative data from NE Syria. METHODS: Frequencies of dental caries per tooth categories, location and size of carious lesions are analyzed using Smith's Mean Measure of Divergence, Correspondence Analysis, χ2 and Kruskal-Wallis tests. RESULTS: There are minimal differences in overall frequencies of carious lesions at Iranian sites, regardless of the chronology, but notable differences at Syrian sites. The inter-tooth pattern at the Iron Age cemetery in Estark appears distinctly different than the other Iranian sites and the comparative samples from Syria. CONCLUSIONS: Divergent subsistence strategies may be linked with different inter-tooth patterns since people buried at Estark were mobile herders, while the other cemeteries were used by settled farmers. SIGNIFICANCE: This comprehensive research on dental caries in three chronologically diverse populations in Iran sheds light on the association between dental caries and subsistence strategies, and introduces the Smith's Mean Measure of Divergence to explore inter-tooth carious patterns, which may prove useful to other researchers seeking to understand the relationships between subsistence, diet, and the presence of carious lesions. LIMITATIONS: The studied sample size is relatively small and therefore its temporal/regional distribution produces low-resolution results. SUGGESTIONS FOR FURTHER RESEARCH: More systematic research on the patterns of dental caries is necessary to produce more fine-grained reconstructions of diet and subsistence in Iran and around the globe.

Human brains preserve in diverse environments for at least 12 000 years.

The brain is thought to be among the first human organs to decompose after death. The discovery of brains preserved in the archaeological record is therefore regarded as unusual. Although mechanisms such as dehydration, freezing, saponification, and tanning are known to allow for the preservation of the brain on short time scales in association with other soft tissues (≲4000 years), discoveries of older brains, especially in the absence of other soft tissues, are rare. Here, we collated an archive of more than 4400 human brains preserved in the archaeological record across approximately 12 000 years, more than 1300 of which constitute the only soft tissue preserved amongst otherwise skeletonized remains. We found that brains of this type persist on time scales exceeding those preserved by other means, which suggests an unknown mechanism may be responsible for preservation particular to the central nervous system. The untapped archive of preserved ancient brains represents an opportunity for bioarchaeological studies of human evolution, health and disease.

Why aquatic scientists should use sulfur stable isotope ratios (ẟ34S) more often.

Over the last few decades, measurements of light stable isotope ratios have been increasingly used to answer questions across physiology, biology, ecology, and archaeology. The vast majority analyse carbon (δ13C) and nitrogen (δ15N) stable isotopes as the 'default' isotopes, omitting sulfur (δ34S) due to time, cost, or perceived lack of benefits and instrumentation capabilities. Using just carbon and nitrogen isotopic ratios can produce results that are inconclusive, uncertain, or in the worst cases, even misleading, especially for scientists that are new to the use and interpretation of stable isotope data. Using sulfur isotope values more regularly has the potential to mitigate these issues, especially given recent advancements that have lowered measurement barriers. Here we provide a review documenting case studies with real-world data, re-analysing different biological topics (i.e. niche, physiology, diet, movement and bioarchaeology) with and without sulfur isotopes to highlight the various strengths of this stable isotope for various applications. We also include a preliminary meta-analysis of the trophic discrimination factor (TDF) for sulfur isotopes, which suggest small (mean -0.4 ± 1.7 ‰ SD) but taxa-dependent mean trophic discrimination. Each case study demonstrates how the exclusion of sulfur comes at the detriment of the results, often leading to very different outputs, or missing valuable discoveries entirely. Given that studies relying on carbon and nitrogen stable isotopes currently underpin most of our understanding of various ecological processes, this has concerning implications. Collectively, these examples strongly suggest that researchers planning to use carbon and nitrogen stable isotopes for their research should incorporate sulfur where possible, and that the new 'default' isotope systems for aquatic science should now be carbon, nitrogen, and sulfur.

Using craniofacial fluctuating asymmetry to examine the effects of sex, socioeconomic status, and early life experiences on adult age at death in industrial England.

OBJECTIVES: Historical evidence from 18th- and 19th-century England suggests that industrialization's impacts on health were largely negative, especially among marginalized groups. However, available documentary evidence is often biased toward adult men and rarely sheds light on the experiences of other members of the population, such as women and children. Craniofacial fluctuating asymmetry (FA) can serve as a proxy measurement of developmental instability and stress during development. This study examines the associations among age, sex, socioeconomic status (SES), and FA in skeletal samples from industrial-era England. MATERIALS AND METHODS: The sample for this study comes from four industrial-era cemeteries from England (A.D. 1711-1857). Geometric morphometric analyses of three-dimensional landmark coordinate data were used to generate a measure of FA for each individual (Mahalanobis distance). A three-way ANOVA was used to evaluate the impacts of sex, SES, and FA scores on adult age at death (n = 168). RESULTS: Significant associations existed between age at death and SES (p = 0.004) and FA scores (p = 0.094). Comparisons of the estimated means indicated that age at death was consistently higher among high SES individuals and individuals with FA scores less than one standard deviation from the mean. CONCLUSIONS: This study supports findings from previous studies that have suggested that the differences in resource access and environmental buffering generated by socioeconomic inequality can impact longevity and patterns of mortality among socioeconomic status groups. Likewise, stress in early life-evinced by craniofacial fluctuating asymmetry-can influence observed patterns of longevity in adults decades later.

North Central Asia isotopic database for archaeological samples.

The North Central Asia Isotopic Database (NCAID) is an open-access dataset of stable isotope measurements from archaeological remains, spanning from the Early Neolithic until present-day in North Central Asia. With 3,143 individual entries corresponding to data accumulated over more than 20 years of research, this comprehensive dataset encompasses measurements of stable carbon and nitrogen isotopes in organic fractions from archaeological humans, animals, and plants. NCAID incorporates diverse supporting information, providing geographical information, archaeological context descriptions, and chronology. This resource facilitates research into past human lifeways, paleo-environments/climates, and animal management practices throughout North Central Asia and will be continually updated as more novel data is released.

Disability and care in Western Europe during Medieval times: A bioarchaeological perspective.

This Special Issue has its foundation in presentations delivered in the symposium Disability and Care in Medieval Times: a Bioarchaeological Perspective into Health-related Practices held at the 2019 European Association of Archaeologists conference in Switzerland. It comprises 12 papers, all relevant to aspects of pathology experience and/or care provision in Western Europe during the Early to Late Middle Ages (500 - 1500 CE). Reflecting the 1000 year timespan involved, these papers are characterised by diversity in subject matter and in the lifeways in which they are located, but all contribute to the symposium's primary aim: to demonstrate that our understanding of the Medieval period is enhanced by cross-disciplinary, bioarchaeological research into individual and collective experiences of disability and care. This Introduction provides the background to the 2019 symposium, and briefly discusses the papers contained in the Special Issue which emerged from this.

Perspectives on anemia: Factors confounding understanding of past occurrence.

OBJECTIVE: This paper reviews factors confounding the understanding of the past occurrence of anemia. Using the evidence gathered, a framework is presented of ways forward to enable greater confidence in diagnosing acquired anemia in paleopathology, facilitating insights into longer-term perspectives on this globally relevant condition. RESULTS: To date, porotic lesions have been central to paleopathological investigations of anemia. The fact that porotic bone lesions are omnipresent and have multiple causes but are likely to have a relatively low, age-related frequency in individuals with anemia, a condition that will have been common in past communities, is confounding. METHODS: Establishing frameworks that move away from porotic lesions is proposed to facilitate higher levels of more accurate anemia diagnoses in paleopathology. SIGNIFICANCE: Acceptance of the fundamental principle that anemia may be better considered as a condition requiring metric evaluation of bone structures, supplemented by careful consideration of lesions, will advance understanding of acquired anemia in past communities. Such an approach would provide a clear basis for further consideration of congenital conditions causing anemia, such as sickle-cell disease and thalassemia. LIMITATIONS: This paper simply opens the conversation on the better diagnosis of anemia in paleopathology; it starts the iterative process of achieving some consensus and progress on diagnosing anemia in paleopathology. SUGGESTIONS FOR FURTHER RESEARCH: Engagement with ideas presented, sharing data and development of metric parameters will assist in identifying the effects of marrow hyperplasia on bone, enabling more robust work on the important topic of anemia.

Menarche at Amarna: Timing and the further implications.

OBJECTIVE: This article examines skeletal development in non-elite individuals from Amarna to identify the age of menarche. MATERIALS AND METHODS: The total sample (n = 267; 65 female, 39 male, 163 indeterminate) was examined for six variables indicative of the pubertal stage (mineralization of the mandibular canine root [n = 46], distal radius fusion [n = 227], proximal ulna fusion [n = 220], distal humerus fusion [n = 237], presence of the iliac crest epiphysis [n = 24], iliac crest fusion [n = 199]). Age and sex estimates are based on standard criteria for dental development and eruption, cranial and pelvic morphology, and post-cranial metric analysis. RESULTS: The iliac crest epiphysis is rarely present before age 15 years. Beginning fusion of the distal radius and iliac crest suggests that by age 19, most individuals have entered the maturation phase, providing book ends for the timing of menarche. Variables elucidating the peak height velocity (proximal ulna and distal humerus fusion) narrow that span and suggest menarche is achieved around 15-17 years for most individuals, with a broader estimate of 14-19 years encompassing the known diversity in timing of menarche. DISCUSSION: Menarche is commonly cited as an indicator of adult status. The observed later entrance into this life stage, and the associated reduced fertility, has broader implications for understanding of economic, social, biological, and demographic patterns observed at Amarna and among different social groups in the ancient city, as well as individual life histories.

Ancient human dental calculus metadata collection and sampling strategies: Recommendations for best practices.

OBJECTIVES: Ancient human dental calculus is a unique, nonrenewable biological resource encapsulating key information about the diets, lifestyles, and health conditions of past individuals and populations. With compounding calls its destructive analysis, it is imperative to refine the ways in which the scientific community documents, samples, and analyzes dental calculus so as to maximize its utility to the public and scientific community. MATERIALS AND METHODS: Our research team conducted an IRB-approved survey of dental calculus researchers with diverse academic backgrounds, research foci, and analytical specializations. RESULTS: This survey reveals variation in how metadata is collected and utilized across different subdisciplines and highlights how these differences have profound implications for dental calculus research. Moreover, the survey suggests the need for more communication between those who excavate, curate, and analyze biomolecular data from dental calculus. DISCUSSION: Challenges in cross-disciplinary communication limit researchers' ability to effectively utilize samples in rigorous and reproducible ways. Specifically, the lack of standardized skeletal and dental metadata recording and contamination avoidance procedures hinder downstream anthropological applications, as well as the pursuit of broader paleodemographic and paleoepidemiological inquiries that rely on more complete information about the individuals sampled. To provide a path forward toward more ethical and standardized dental calculus sampling and documentation approaches, we review the current methods by which skeletal and dental metadata are recorded. We also describe trends in sampling and contamination-control approaches. Finally, we use that information to suggest new guidelines for ancient dental calculus documentation and sampling strategies that will improve research practices in the future.

Age estimation from alveolar bone loss, re-evaluation of Ruquet's method.

There are many dental age estimation methods, but all the methods do not correspond, especially for aging methods for adults and mature individuals, to the reality of the forensic field, which favors simple, effective, and easy-to-use methods. Ruquet (2015) developed a method based on alveolar bone loss that predicts age for individuals between 25 and 60 years old and is even more accurate for those 25-40 years old. This study re-evaluated Ruquet's alveolar bone loss method using three-dimensional imaging of individuals whose age and sex were known, without taking into account their medical conditions. Digital measurements, from the cemento-enamel junction (CEJ) to the alveolar bone crest (ABC), were performed on the mesial and distal surfaces of teeth on 243 patients, independent of the tridimensional imaging test. With these measurements, two alveolar bone loss averages (ABL) were calculated, one with all the teeth present on the arches and another with only Ramfjörd's teeth. Bone loss showed a significant correlation with age (p < 0.001). The age estimation with all teeth and with only Ramfjörd's teeth showed a statistically significant difference, and age estimation was more accurate when all teeth were used. The assessment of alveolar resorption appears to be an interesting tool for age estimation in adult individuals. However, the method still lacks precision, and the mean absolute errors (MAEs) obtained by age group were all greater than 5 years, except for the age group 35-39 years old, for the age estimation with all teeth. Further studies should explore this existing correlation between alveolar bone loss and age and refine this method to make it more accurate.

Estimating adult age categories in commingled skeletons with Transition Analysis 3.

OBJECTIVES: We estimate adult age frequencies from Unar 1 and Unar 2, two late Umm an-Nar (2400-2100 BCE) tombs in the modern-day Emirate of Ras al-Khaimah, United Arab Emirates. These collective tombs each contained hundreds of skeletons in commingled, fragmented, and variably cremated states. Previous studies placed the vast majority of this mortuary community in a generalized "adult" category, as have most analyses of similar tombs from this period. We sought to test how adult age estimation methods compare in identifying young, middle, and old-age individuals in commingled assemblages. MATERIALS AND METHODS: We employed Transition Analysis 3 (TA3) and traditional age estimation methods to generate adult age frequencies for each tomb. We compared these frequencies between tomb contexts as well as by method. RESULTS: Unar 1 and Unar 2 had similar adult age frequencies within each method, but TA3 age frequencies included significantly more middle and older adult individuals than those generated by traditional methods. DISCUSSION: These results support findings of earlier iterations of transition analysis in regard to sensitivity in old adult age estimation, compared with traditional methods. Our findings indicate a potential use of TA3 in reconstructing age frequencies and mortality profiles in commingled skeletal assemblages. Increasing our understanding of everyday life in the distant past necessitates better understandings of adult age, and here, we illustrate how age estimation method choice significantly changes bioarchaeological interpretations of aging in Bronze Age Arabia. RESEARCH HIGHLIGHTS: Adult age estimation using TA3 revealed significantly more middle and older adults than traditional methods in two commingled tombs. Similar mean maximum likelihood point estimates by side and across skeletal elements were found between tombs.

Variability in human tooth cementum thickness reflecting functional processes.

OBJECTIVE: The aim of this study was to investigate the thickness of acellular extrinsic fibre cementum (AEFC) at four root positions of anterior and posterior teeth with special focus on functional aspects. Furthermore, the correlations between cementum thickness and chronological age and sex are investigated. BACKGROUND: While numerous studies confirm continuous cementum apposition with age, masticatory forces as well as physiological and orthodontically induced tooth movements also have the potential to affect tooth cementum thickness. MATERIALS AND METHODS: Undecalcified teeth were embedded in resin and transverse-sectioned in the cervical third of the root. Two sections per root were selected, and digital images at four positions were obtained (mesial, distal, oral, and vestibular) using light microscopy. The AEFC thickness of 99 teeth (anterior = 66, posterior = 33, male = 54, female = 45) were measured in both sections. The differences in mean values between root positions and the association of root position variation with tooth type, age, sex, and subject as well as the overall effects of age and sex were analysed using a mixed model. RESULTS: First incisors and canines showed the greatest mean AFEC thickness, in contrast to premolars which had the lowest values. Differences were found across the four root positions, with a pattern varying considerably between anterior and posterior teeth and between maxilla and mandible in the anterior teeth. An interaction between root position and subject pointed to the existence of an individual component in the variation of AEFC thickness across the four root positions. There was an age trend with an almost linear increase in cementum thickness of 1 µm per year. Overall, females tended to exhibit a significantly lesser AEFC thickness compared to males. CONCLUSIONS: Distinct differences in the pattern of thickness values across the four root positions in anterior and posterior teeth support the assumption that the AEFC is strongly affected by functional processes. In addition to sex-specific differences and age-related trends, the root position variation of AEFC thickness varies from individual to individual.

Advances in commingled human remains analysis between 2014 and 2023.

This study reviews recent advances in osteometric, genetic, geochemical, and digital modeling applications since 2014 to demonstrate the expanded range of analyses and skeletal elements that can be used to separate individuals from commingled contexts. While traditional methods remain foundational to commingling resolution, new advances allow increased individuation, identification of human versus non-human remains, and an amplified scale of assemblages that can be analyzed. This summary offers ways for practitioners to consider the juxtaposition of analytical goals, time, financial concerns, and methods when managing commingled assemblages. Forensic anthropology and bioarchaeology case studies illustrate differences related to application of methods in terms of recovery environments, project goals, and recovered materials. Whether the goal is to isolate and individuate only major elements or as many bones as possible, in nearly all cases, it is best practice to combine several types of methods to fulfill the project scope within the established parameters. This review can help practitioners identify the most appropriate analytical protocols and methods for their projects.