Analysis of oral conditions to explore subsistence strategies in the ecologically diverse environments of the Canary Islands during the Amazigh period (1st to 15th centuries CE)

OBJECTIVE

This study examines oral health conditions in the pre-European Amazigh population of the Canary Islands (1st-15th centuries) to uncover patterns linked to island-specific environments and subsistence practices. The Canary Islands offered diverse ecological settings that shaped how the Amazigh adapted their agricultural practices, creating landscapes to support settlement.

DESIGN

By analyzing the oral health of 615 adult individuals across seven major islands-including caries, dental wear, calculus, periodontal disease, and antemortem tooth loss-the study identifies three distinct patterns of oral health within the archipelago.

RESULTS

Gran Canaria exhibited the highest prevalence of dental caries, aligning with an agriculture-centered lifestyle. In contrast, La Gomera, Fuerteventura, and Lanzarote showed the lowest caries rates, suggesting less agricultural dependence. El Hierro and La Palma populations presented both high caries prevalence and extensive dental wear, likely due to a diet including famine-related foods like fern roots. The findings also indicate sex-based differences in oral health across islands but no significant distinctions by age.

CONCLUSIONS

These patterns highlight a relationship between the diverse biogeography of the islands, subsistence strategies, and oral health in the Amazigh period. This study contributes valuable insights into how different environments and resource availability impacted the diet and health of the Canary Islands' Amazigh populations.

An 'Index of Oro-dental Disease': A holistic method for understanding the impacts of different risk factors on oral health in archaeological populations

OBJECTIVE

To gain a more holistic understanding of oral health in the past by producing an 'Index of Oro-dental Disease' (IOD), incorporating multiple oro-dental diseases and accounting for differences in antemortem/postmortem alveolar bone and tooth loss.

MATERIALS

UK Adult Dental Health Survey, 2009 anonymised dataset (N = 6206). Archaeological dental data from skeletal individuals from medieval and post-medieval Barton-upon-Humber, North Lincolnshire (N = 214, 1150-1855) and St James's Gardens Burial Ground, London (N = 281, 1789-1853).

METHODS

Creation of a formula for the production of index values. Application of the formula to clinical, 'mock archaeological', and archaeological datasets.

RESULTS

Patterns in mean IOD values within different groups were identifiable regardless of preservation. It was possible to identify potential differences between IOD scores related to aging, tobacco consumption, geographical location, and time period.

CONCLUSIONS

Innovative use of modern clinical data and the production of 'mock archaeological' datasets provides validation of the IOD method. The approach may be useful for understanding the impact of different risk factors on oral health in the past, whilst also accounting for missing data and increasing comparability between groups.

SIGNIFICANCE

Allows for the investigation of risk factors that affect overall oral health but manifest in different ways in different individuals, whilst also producing larger sample sizes.

LIMITATIONS

Impacts of age and posterior/anterior site positioning within the mouth suggest a careful consideration of age distribution and preservation of samples is required.

FUTURE RESEARCH

Future adaption and testing of the method on a greater range of population groups and different variables/risk factors for oro-dental disease.

What Doesn't Kill You Makes You Stronger? Examining Relationships Between Early-Life Stress, Later-Life Inflammation and Mortality Risk in Skeletal Remains

OBJECTIVES

This paper explores conflicting perspectives on the adaptive significance of phenotypic plasticity during fetal and early postnatal development and the impact that stressors experienced during this critical early-life period have on later-life morbidity and mortality risk.

METHODS

The sample (n = 216) comprised archeologically-recovered human skeletons. A geometric morphometric (GM) method was employed to evaluate first permanent molar (M1) fluctuating asymmetry (FA) and provide a proxy for early-life stress. Shifts in later-life physiology were inferred through two inflammatory lesions: periosteal new bone formation (PNBF) and periodontal disease (PD). To explore mortality risk, age-at-death was estimated through dental development for skeletally immature individuals (n = 104) and through senescent skeletal changes for mature skeletons (n = 112).

RESULTS

Significant differences were found in M1 FA between groups, with the immature cohort associated with elevated FA. Within-group analysis revealed age-at-death in the immature group had a significant positive relationship with M1 FA and PD presence. In the mature group, alongside sex and the co-occurrence of PD and PNBF, FA was a significant predictor of a shorter life. Higher FA was also associated with active and bilaterally expressed PNBF.

CONCLUSIONS

It is theorized that early-life stress, if survived, programmed a hyperinflammatory response to environmentally-mediated physiological perturbations which increased the chances of survival during subsequent development but also elevated later-life mortality risk. Findings demonstrate a complicated relationship between developmental stress and physiological shifts that helps to illustrate the adaptive significance of early-life programming and support the Thrifty Phenotype hypothesis.

History of Health at Cayo Santiago-An Investigation of Environmental and Genetic Influences on the Skeletal Remains of the Introduced Rhesus Macaque (Macaca mulatta) Colony

The Cayo Santiago rhesus macaque colony is a renowned primate population that has experienced significant natural and anthropogenic ecological variation in their 85-year history. Demographic and familial information is also tracked and collated for the majority of monkeys. Thus, the health history of rhesus macaques at Cayo Santiago should reflect the impacts of both environmental and genetic factors. In this study, we utilized a sample of skeletal remains comprised of 2787 individuals (1571 females, 1091 males), born between 1938 and 2017 from the derived skeletal collection of the primate colony to assess variation in survivorship, pathology, bone mineral density (BMD), and dental eruption status, in the context of hurricane impacts, nutritional fluctuations, and matriline genealogy. Results demonstrated that rhesus macaques at Cayo Santiago exhibit a range of skeletal pathologies that encompass biomedical and archaeological significance, multiple etiologies, severities, locations, and types, in addition to a secular trend of declining BMD that is hypothesized to reflect decreasing physical activity levels under increasing population densities. Specifically, hurricane impacts were found to increase the rate of systemic disease, decrease BMD in young adults, and delay eruption of the primary dentition. Certain matrilines exhibited heightened levels of systemic disease at early ages while others exhibited greater rates of congenital disease. Early-life adversity, through the experience of major hurricanes, may enhance inflammatory pathways, heightening the risk of disease and accelerating the aging process leading to reduced BMD. Such impacts may underly greater levels of observed infection post-hurricane through intensification of pathogen transmission and disease rates brought on by hurricane-adaptive social strategies that favor closer proximity. Familial susceptibility to disease indicates heritable host genetic factors are likely influencing disease patterning in the population. A cluster of congenital diseases may most convincingly illustrate this, or alternatively reflects low levels of genetic diversity in the population.

Using a multimethod life history approach to navigate the osteological paradox: A case study from Prehispanic Nasca, Peru

OBJECTIVES

We leverage recent bioarchaeological approaches and life history theory to address the implications of the osteological paradox in a study population. The goal of this article is to evaluate morbidity and mortality patterns as well as variability in the risk of disease and death during the Late Intermediate period (LIP; 950-1450 C.E.) in the Nasca highlands of Peru. We demonstrate how the concurrent use of multiple analytical techniques and life history theory can engage the osteological paradox and provide salient insights into the study of stress, frailty, and resilience in past populations.

MATERIALS AND METHODS

Crania from LIP burial contexts in the Nasca highlands were examined for cribra orbitalia (n = 325) and porotic hyperostosis (n = 270). All age groups and both sexes are represented in the sample. Survivor/nonsurvivor analysis assessed demographic differences in lesion frequency and severity. Hazard models were generated to assess differences in survivorship. The relationship between dietary diversity and heterogeneity in morbidity was assessed using stable δ¹⁵ N and δ¹³ C isotope values for bone collagen and carbonate. One hundred and twenty-four crania were directly AMS radiocarbon dated, allowing for a diachronic analysis of morbidity and mortality.

RESULTS

The frequency and expression of both orbital and vault lesions increases significantly during the LIP. Survivor/nonsurvivor analysis indicates cranial lesions co-vary with frailty rather than robusticity or longevity. Hazard models show (1) decreasing survivorship with the transition into the LIP, (2) significantly lower adult life expectancy for females compared to males, and (3) individuals with cranial lesions have lower survivorship across the life course. Stable isotope results show very little dietary diversity. Mortality risk and frequency of pathological skeletal lesions were highest during Phase III (1300-1450 C.E.) of the LIP.

CONCLUSION

Results provide compelling evidence of increasing physiological stress and mortality in the Nasca highlands during the LIP, but also reveal substantial heterogeneity in frailty and the risk of death. Certain members of society experienced a heavier disease burden and higher mortality compared to their contemporaries. Elevated levels of disease and lethal trauma among females account for some of the sex differences in survivorship but cannot explain the large degree of female-biased mortality. We hypothesize that parental investment in males or increased female fertility rates may explain these differences.

An epidemiological approach to the analysis of cribra orbitalia as an indicator of health status and mortality in medieval and post-medieval London under a model of parasitic infection

OBJECTIVES

Many individuals living in medieval and post-medieval London suffered issues with sanitation, food insecurity, infectious disease, and widespread exposure to parasites from a multitude of sources, causing increased risk of death for many inhabitants. We examine this stressful environment and its relationship with various demographic and temporal dimensions, using cribra orbitalia (CO) as an indicator of stress, to model an increased risk of dying under the expectations of our proposed parasitic model of infection.

MATERIALS AND METHODS

We analyze the relationship between CO and mortality across seven medieval and post-medieval cemeteries from London by the covariates of sex, status, and age-at-death. A survival analysis (Cox regression) and a binomial logit estimated hazard and odds ratios of dying with CO across age-at-death, sex, status, and time-period within single statistical models. In addition, we provide new Bayesian age-at-death estimates for post-medieval samples.

RESULTS

The models show the rate of CO decreased over time and age-at-death, regardless of sex or status; post-medieval individuals were ~72% less likely to die with lesions than their medieval counterparts. Further, individuals with CO had ~1% decrease in risk of dying with CO per year of age.

DISCUSSION

These results suggest increased mortality risk for those with lesions indicative of anemia (CO), and selective mortality of younger individuals during the medieval period. Despite sex-specific nutritional and occupational hazards, and status-based access to resources, the prevalence of CO was similar across sex and status, which suggests living with parasitic infection that caused anemia was an everyday reality for medieval and post-medieval Londoners.

Biocultural pathways linking periodontal disease expression to food insecurity, immune dysregulation, and nutrition

OBJECTIVES

In this article, we test theoretical pathways leading to and resulting from periodontal disease to better understand how periodontal disease, which is measurable in both past and present populations, integrates biocultural context and affects whole-body physiology.

METHODS

We use data from the National Health and Nutrition Examination Survey (NHANES) 2003-2004 and logistic and linear regressions to test pathways linking psychosocial stress to periodontal disease, and periodontal disease to serum vitamin C levels. We then use causal mediation analysis to test the role of mediating variables in these pathways (n = 1853 individuals).

RESULTS

Food insecurity was positively associated with periodontal disease and negatively associated with serum counts of C-reactive protein (CRP) and neutrophils. Neither CRP nor neutrophils significantly mediated the relationship between food insecurity and periodontal disease. Periodontal disease was negatively associated with serum vitamin C levels and positively associated with neutrophil counts. Neutrophils may mediate the relationship between periodontal disease and vitamin C.

CONCLUSIONS

We identify two main findings: (a) periodontal disease contributes to and may result from immune dysregulation, particularly of neutrophils, and (b) an immune response to chronic infection such as periodontal disease is metabolically expensive for the body to maintain and likely depletes serum micronutrient levels. Both micronutrient status and serum neutrophil counts affect multiple skeletal and physiological phenotypes and thus position periodontal disease in whole-body context.

Dental health in adults and subadults from the 16th-century plague cemetery of Alghero (Sardinia, Italy)

OBJECTIVE

The aim of this study is to examine a set of dental health indicators, including caries, periodontal disease, abscesses, ante-mortem tooth loss, calculus, and tooth wear of a 16^th-century population from the city of Alghero, Sardinia (Italy), in order to evaluate the state of dental health and the diet.

DESIGN

The cemetery is referable to the plague outbreak that ravaged the city in 1582-1583. A total of 160 individuals (81 adults and 79 subadults) were suitable for dental examination.

RESULTS

The oral conditions of the urban population of Alghero are characterised by high frequency of carious lesions, periodontal disease, ante mortem tooth loss, and calculus, but a low prevalence of abscesses and moderate tooth wear are recorded. In general, no statistically significant sexual differences are observed, suggesting a uniform scenario for diet access and oral health. The subadult subsample shows moderate rates of caries and is affected by calculus. The results suggest that the diet was rich in soft and refined food, with a prevalence of carbohydrates and cariogenic aliments; the effects of the diet are associated with a lack of oral hygiene.

CONCLUSIONS

The patterns of dental health observed in the Alghero population fit with the data observed in other Modern Age samples, reflecting increased prevalence of dentoalveolar diseases resulting from a less abrasive diet and an increase in carbohydrate consumption, as documented during the transition from the Middle Ages to the Modern period.

Child development, physiological stress and survival expectancy in prehistoric fisher-hunter-gatherers from the Jabuticabeira II shell mound, South Coast of Brazil

In this study, we shed light on the interdependency of child growth, morbidity and life expectancy in the fisher-hunter-gatherers of the Jabuticabeira II shell mound (1214-830 cal B.C.E. - 118-413 cal C.E.) located at the South Coast of Brazil. We test the underlying causes of heterogeneity in frailty and selective mortality in a population that inhabits a plentiful environment in sedentary settlements. We reconstruct osteobiographies of 41 individuals (23 adults and 18 subadults) using 8 variables, including age-at-death, stature, non-specific stress markers (cribra orbitalia, porotic hyperostosis, periosteal reactions, periapical lesions and linear enamel hypoplasia), as well as weaning patterns based on stable isotope data to examine how stress factors module growth and survival. Our results show that shorter adult statures were linked to higher morbidity around weaning age and higher chances of dying earlier (before 35 years) than taller adult statures. In addition, short juvenile stature was related to physiological stressors and mortality. The adult "survivors" experienced recurrent periods of morbidity during childhood and adulthood, possibly associated with the high parasite load of the ecosystem and dense settlement rather than to malnourishment. An association between early-stress exposure and premature death was not demonstrated in our sample. To explain our data, we propose a new model called "intermittent stress of low lethality". According to this model, individuals are exposed to recurrent stress during the juvenile and adult stages of life, and, nevertheless survive until reproductive age or later with relative success.

The Bioarchaeology of Health Crisis: Infectious Disease in the Past

Beginning some 10,000 years ago, humans began a dramatic alteration in living conditions relating especially to the shift in lifeway from foraging to farming. In addition to the initiation of and increasing focus on the production and consumption of domesticated plant carbohydrates, this revolutionary transformation in diet occasioned a decline in mobility and an increased size and agglomeration of populations in semipermanent or permanent settlements. These changes in life conditions presented an opportunity for increased transmission of pathogenic microbes from host to host, such as those that cause major health threats affecting most of the 7.5 billion members of our species today. This article discusses the bioarchaeology of infectious disease, focusing on tuberculosis, treponematosis, dental caries, and periodontitis, all of which continue to contribute to high levels of morbidity and mortality among the world's populations today.

Frail or hale: Skeletal frailty indices in Medieval London skeletons

To broaden bioarchaeological applicability of skeletal frailty indices (SFIs) and increase sample size, we propose indices with fewer biomarkers (2-11 non-metric biomarkers) and compare these reduced biomarker SFIs to the original metric/non-metric 13-biomarker SFI. From the 2-11-biomarker SFIs, we choose the index with the fewest biomarkers (6-biomarker SFI), which still maintains the statistical robusticity of a 13-biomarker SFI, and apply this index to the same Medieval monastic and nonmonastic populations, albeit with an increased sample size. For this increased monastic and nonmonastic sample, we also propose and implement a 4-biomarker SFI, comprised of biomarkers from each of four stressor categories, and compare these SFI distributions with those of the non-metric biomarker SFIs. From the Museum of London WORD database, we tabulate multiple SFIs (2- to 13-biomarkers) for Medieval monastic and nonmonastic samples (N = 134). We evaluate associations between these ten non-metric SFIs and the 13-biomarker SFI using Spearman's correlation coefficients. Subsequently, we test non-metric 6-biomarker and 4-biomarker SFI distributions for associations with cemetery, age, and sex using Analysis of Variance/Covariance (ANOVA/ANCOVA) on larger samples from the monastic and nonmonastic cemeteries (N = 517). For Medieval samples, Spearman's correlation coefficients show a significant association between the 13-biomarker SFI and all non-metric SFIs. Utilizing a 6-biomarker and parsimonious 4-biomarker SFI, we increase the nonmonastic and monastic samples and demonstrate significant lifestyle and sex differences in frailty that were not observed in the original, smaller sample. Results from the 6-biomarker and parsimonious 4-biomarker SFIs generally indicate similarities in means, explained variation (R2), and associated P-values (ANOVA/ANCOVA) within and between nonmonastic and monastic samples. We show that non-metric reduced biomarker SFIs provide alternative indices for application to other bioarchaeological collections. These findings suggest that a SFI, comprised of six or more non-metric biomarkers available for the specific sample, may have greater applicability than, but comparable statistical characteristics to, the originally proposed 13-biomarker SFI.

Do leprosy and tuberculosis generate a systemic inflammatory shift? Setting the ground for a new dialogue between experimental immunology and bioarchaeology

It is possible that during long lasting chronic infections such as tuberculosis (TB) and leprosy individuals who generate a stronger immune response will produce a chronic shift in the systemic levels of inflammatory proteins. Consequently, the systemic immunological shift could affect inflammatory responses against other persistent pathogens such as Porphyromonas gingivalis associated with periodontal disease (PD).

OBJECTIVE

To determine if in vitro exposure to Mycobacterium tuberculosis or M. leprae lysates impacts subsequent immune responses to P. gingivalis; and to propose a new dialogue between experimental immunology and paleopathology.

MATERIAL AND METHODS

We sequentially (2 days protocol) exposed peripheral blood mononuclear cells (PBMCs) from healthy donors to bacterial lysates either from M. tuberculosis, or M. leprae, or P. gingivalis. After collecting all supernatants, we measured the expression of immune proteins TNFα and IFNγ using an enzyme-linked immunosorbent assay.

RESULTS

Early exposure (day 1) of PBMCs to M. leprae or M. tuberculosis lysates induces an inflammatory shift detected by the increase of TNFα and IFNγ when the same cells are subsequently (day 2) exposed to oral pathogen P. gingivalis.

DISCUSSION

By extrapolating these results, we suggest that chronic infections, such as TB and leprosy, could generate a systemic immunological shift that can affect other inflammatory processes such the one present in PD. We propose that the presence and severity of PD should be explored as a proxy for inflammatory status or competence when reconstructing the health profile in past populations.

Osteoarchaeological Studies of Human Systemic Stress of Early Urbanization in Late Shang at Anyang, China

Through the analysis of human skeletal remains and mortuary practice in Yinxu, this study investigates the impact of early urbanization on the commoners during the Late Shang dynasty (ca. 1250-1046 B.C.). A total of 347 individuals examined in this study represent non-elites who were recovered from two different burial contexts (formally buried in lineage cemeteries and randomly scattered in refuse pits). Frequencies of enamel hypoplasia (childhood stress), cribra orbitalia (childhood stress and frailty) and osteoperiostitis (adult stress) were examined to assess systemic stress exposure. Our results reveal that there was no significant difference in the frequency of enamel hypoplasia between two burial groups and between sexes, suggesting these urban commoners experienced similar stresses during childhood, but significantly elevated levels of cribra orbitalia and osteoperiostitis were observed in the refuse pit female cohort. Theoretically, urbanization would have resulted in increased population density in the urban centre, declining sanitary conditions, and increased risk of resource shortage. Biologically, children would be more vulnerable to such physiological disturbance; as a result, high percentages of enamel hypoplasia (80.9% overall) and cribra orbitalia (30.3% overall) are observed in Yin commoners. Adults continued to suffer from stress, resulting in high frequencies of osteoperiostitis (40.0% total adults); in particular, in the refuse pit females who may also reflect a compound impact of gender inequality. Our data show that the non-elite urban population in the capital city of Late Shang Dynasty had experienced extensive stress exposure due to early urbanization with further social stratification only worsening the situation, and eventually contributing to collapse of the Shang Dynasty.