Skeletal growth in early and late Neolithic foragers from the Cis-Baikal region of Eastern Siberia

Analyzing Patterns of Skeletal Indicators of Developmental Stress Through the Double Lens of Ontogeny and the Life Course Approach in a Contemporary Reference Sample

OBJECTIVES

Skeletal indicators of developmental stress are commonly used to assess health, disease, and patterns of morbidity and mortality in past populations. Incorporating information about individual life history, such as adverse life events, allows for a more thorough understanding of their etiology. This paper adopts the double lens of ontogeny and the life course to analyze indicators of developmental stress in relation to known individual pathologies and developmental patterns of the cranium, vertebrae, and long bones.

MATERIAL AND METHODS

Six skeletal indicators were collected on CT scans or virtual skeletal reconstructions of 1033 contemporary deceased male and female individuals aged between 0 and 20 years from New Mexico: cribra orbitalia, porotic hyperostosis, Harris lines, stunting, vertebral neural canal diameters, and bone mineral density. Autopsy reports provided information on age, sex, disease type, and duration. Polychoric and polyserial correlations, boxplots, balloon plots, factor analyses of mixed data, and cluster analyses were used to explore patterns among indicators, ontogeny, sex, and disease.

RESULTS

The presence and prevalence of indicators varied depending on age and disease: Harris lines, stunted growth, and cribra orbitalia were common in younger age groups and in cases of long-term or respiratory illnesses, while porotic hyperostosis was more prevalent in adolescent and young adult males.

DISCUSSION

Skeletal indicators of developmental stress are most likely associated with the timing of adverse life events in relation to the corresponding ontogenetic patterns, developmental sensitivity to stressors, and developmental plasticity/canalization of the different skeletal elements that bear them.

Exploring developmental changes in femoral midneck cross-sectional properties

This research delves deeper into previous works on femoral cross-sectional properties during ontogeny by focusing for the first time on the human femoral midneck. The ontogenetic pattern of cross-sectional properties at femoral midneck is established and compared with those at three different femoral locations: the proximal femur, the midshaft, and the distal femur. The study sample includes 99 femora (70 non-adults and 29 adults) belonging to archaeological specimens. Cross-sectional properties were extracted from computed tomographic scans and analyzed with the MomentMacro plugin of ImageJ. Ontogenetic trends of these variables were assessed using locally estimated scatterplot smoothing and segmented regressions, along with Wilcoxon post hoc tests for all possible age group pairings. Our results show that the femoral midneck exhibits a unique growth pattern. Area variables showed rapid growth until adolescence, followed by a more gradual increase leading into adulthood. Nonetheless, the relative cortical area does not demonstrate any significant drops or rise during growth. The morphology of the midneck section of the femur remains stable during ontogeny, with early adolescence and the onset of adulthood marking two periods of significant change. In contrast to the femoral diaphysis, the acquisition of a mature bipedal gait does not appear to constitute a period of significant morphological change at the femoral midneck cross section.

Child dietary patterns in Homo sapiens evolution: A systematic review

Dietary patterns spanning millennia could inform contemporary public health nutrition. Children are largely absent from evidence describing diets throughout human evolution, despite prevalent malnutrition today signaling a potential genome-environment divergence. This systematic review aimed to identify dietary patterns of children ages 6 months to 10 years consumed before the widespread adoption of agriculture. Metrics of mention frequency (counts of food types reported) and food groups (globally standardized categories) were applied to: compare diets across subsistence modes [gatherer-hunter-fisher (GHF), early agriculture (EA) groups]; examine diet quality and diversity; and characterize differences by life course phase and environmental context defined using Köppen-Geiger climate zones. The review yielded child diet information from 95 cultural groups (52 from GHF; 43 from EA/mixed subsistence groups). Animal foods (terrestrial and aquatic) were the most frequently mentioned food groups in dietary patterns across subsistence modes, though at higher frequencies in GHF than in EA. A broad range of fruits, vegetables, roots and tubers were more common in GHF, while children from EA groups consumed more cereals than GHF, associated with poor health consequences as reported in some studies. Forty-eight studies compared diets across life course phases: 28 showed differences and 20 demonstrated similarities in child versus adult diets. Climate zone was a driver of food patterns provisioned from local ecosystems. Evidence from Homo sapiens evolution points to the need for nutrient-dense foods with high quality proteins and greater variety within and across food groups. Public health solutions could integrate these findings into food-based dietary guidelines for children.

Interpreting error in the estimation of skeletal growth profiles from past populations: An example demonstrating skeletal growth in historic African American communities

OBJECTIVES

The study of growth in the past is a critical component of bioarcheological analyses. However, our understanding of growth in the past is subject to a number of methodological challenges. This study aims to model the skeletal growth of past populations by considering the challenges associated with the data collection process and the challenges associated with the age estimation procedures.

MATERIALS AND METHODS

We use skeletal remains from two historic African American cemeteries in the American South to model femoral diaphyseal length-for-age. We estimate the age of each individual using dental development techniques and present growth curves as both a product of the maximum likelihood (MLE) age estimate and the estimated posterior age distribution. Growth was compared against a reference sample from the University of Colorado Child Research Council Study.

RESULTS

The results of our analyses showed that femoral diaphyseal length in two historic African American communities is small-for-estimated age as compared to a modern reference sample. However, the magnitude and characterization of this difference is variable when taking into account the broader posterior age distribution.

DISCUSSION

Both samples may be small-for-age due to physiological stress associated with racism, inequality, and the compounding effects of early urbanization. However, the interpretation of growth in the past is muddled when considering the relationship between the study sample and the reference sample, when accounting for uncertainty in the age estimation procedure, and the error-inducing steps taken during the data collection process. Future interpretation of skeletal growth in the past must include a full account of the possible sources of error in order to present an accurate representation of growth.

What is normal bone health? A bioarchaeological perspective on meaningful measures and interpretations of bone strength, loss, and aging

Bioarchaeological (the study of archeological human remains together with contextual and documentary evidence) offers a unique vantage point to examine variation in skeletal morphology related to influences such as activity, disease, and nutrition. The human skeleton is composed of a dynamic tissue that is forged by biocultural factors over the entire life course, providing a record of individual, and community history. Various aspects of adult bone health, particularly bone maintenance and loss and the associated skeletal disease osteoporosis, have been examined in numerous past populations. The anthropological study of bone loss has traditionally focused on the signature of postmenopausal aging, costs of reproduction, and fragility in females. The a priori expectation of normative sex-related bone loss/fragility in bioanthropological studies illustrates the wider gender-ideological bias that continues in research design and data analysis in the field. Contextualized data on bone maintenance and aging in the archeological record show that patterns of bone loss do not constitute predictable consequences of aging or biological sex. Instead, the critical examination of bioarchaeological data highlights the complex and changing processes that craft the human body over the life course, and calls for us to question the ideal or "normal" range of bone quantity and quality in the human skeleton, and to critically reflect on what measures are actually biologically and/or socially meaningful.

Transcriptome analysis of body wall reveals growth difference between the largest and smallest individuals in the pure and hybrid populations of Apostichopus japonicus

Long-term inbreeding of sea cucumber has resulted in a decrease in its growth rate, which has severely affected yield and economic efficiency. In this study, three Apostichopus japonicus families were constructed and screened into the weight of smallest and largest, which included Russian, Chinese, and their hybrids (RC). We examined the transcriptional profiles of hybrid (RC) and purebred (CC and RR). A total of 49.69 Gb clean reads were obtained, and the Q30 base percentage was above 90.47%. A total of 5191 novel genes were discovered, of which 2592 genes were annotated. Differentially expressed genes (DEGs) were identified, and functional annotation and enrichment analysis were performed. Approximately 1874 DEGs were screened in the Chinese sea cucumber (CC) difference group; 2591 DEGs were obtained in the hybrid sea cucumber difference group (RC), and 3006 DEGs were obtained in the Russian sea cucumber difference group (RR). In Gene Ontology (GO) analysis, highest DEG enrichment was observed for the functional categories of cellular process and metabolic process. In terms of cellular components, DEG enrichment was observed in cell part, cell; for molecular function, DEG enrichment was detected in catalytic activity, binding, hydrolase activity, transferase activity. According to the differential expression analysis, we found that 15 heat shock protein (HSP) genes that have the same expression trends, which were upregulated in the smallest weight of three sea cucumber lines. In addition, COG analysis of defense genes was conducted. All defense genes (ATP-binding cassette transporters (ABCs), multidrug resistance protein (MRPs), and beta-lactamase) showed the same expression trend, which was significantly upregulated in smallest individuals compared to that of largest individuals in RC lines, which implied the smallest individuals are exposed to more pressure during growth. These results may lead to the smallest individuals showing slow growth. Additionally, we selected 12 DEGs to validate the result by qPCR. Those DEGs were included in growth-related and resistance genes. Sequencing of the A. japonicus transcriptome improves our understanding of the transcriptional regulatory apparatus that controls individual development and growth.

Crypt fenestration enamel defects and early life stress: Contextual explorations of growth and mortality in Colonial Peru

OBJECTIVES

This study provides a comprehensive analysis of crypt fenestration enamel defects (CFEDs) from the Eten and Mórrope communities, Colonial period (A.D. 1,530-1,750), Lambayeque Valley, Peru. The goal is to help clarify the role of these lesions as reflections of early life environments as well as relationships growth and survival at future ages.

MATERIALS AND METHODS

CFED absence/presence was recorded in the mandibular canines of 105 individuals and 202 teeth. Defect prevalence was compared between the Eten and Mórrope sites using a proportions test. Femoral growth residuals were compared between CFED present and absent samples. Mortality risk was evaluated using Kaplan-Meier survival analysis.

RESULTS

CFED frequencies at Eten and Mórrope were similar to previous studies. Greater frequencies of CFEDs were found at Eten compared to Mórrope. There was no association between skeletal growth and CFEDs. No differences in mortality were found between CFED present and absent individuals within each site. General survivorship at Eten was significantly greater than Mórrope. However, individuals without CFEDs at Eten had greater survivorship than those with and without CFEDs at Mórrope. Individuals with CFEDs at Eten had greater survivorship than those with CFEDs at Mórrope. These differences begin around 1.7 years.

CONCLUSIONS

CFEDs may be associated with stress experience, but associations with growth and survivorship at later ages is context dependent. CFED prevalence is an ambiguous indicator of stress when used in the absence of mortality data, and even under those circumstances, appears limited by differences in local demography.