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Porous cranial lesions (cribra cranii and cribra orbitalia) are widely used by archaeologists as skeletal markers of poor child health. However, their use has not been validated with systematic data from contemporary populations, where there has been little evidence of these lesions or their health relevance. Using 375 in vivo computed tomography scans from a cohort-representative sample of adults aged 40+ years from the Bolivian Amazon, among food-limited, high-mortality forager-farmers, we identified cribra cranii on 46 (12.3%) and cribra orbitalia on 23 (6%). Cribra orbitalia was associated with several hallmarks of compromised immune function, including fewer B cells, fewer naïve CD4+T cells, a lower CD4+/CD8+T cell ratio, and higher tuberculosis risk. However, neither lesion type predicted other physician-diagnosed respiratory diseases, other markers of cell-mediated immunity, or hemoglobin values. While cribra orbitalia shows promise as a skeletal indicator of health challenges, our findings do not support the continued practice of using these lesions to infer anemia in adults.
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This content will become publicly available on March 1, 2027
Known unknowns and the osteological paradox: Why bioarchaeology needs agent-based models
Objective: This paper demonstrates computational modeling’s value as a tool for mapping the impact of hidden variables and evaluating the accuracy of statistical methods in bioarchaeology. Materials: As a working example, this paper presents an agent-based model of a 1,000-person cohort of in- dividuals who can form an unspecified skeletal lesion at any age between birth and ten years and enter a simulated cemetery at the end of their lives. Skeletal lesions either have no effect on mortality risk (scenario 1) or are associated with doubled mortality risk (scenario 2). Methods: The agent-based model simulates data on individual age at death and lesion status. Kaplan-Meier survival analysis is run on each simulated dataset, comparing survival estimates for individuals with and without lesions. Results: Survival analyses underestimate the true value of lesion-associated mortality risk in early life in scenario 2 and produce a false lesion-associated survival advantage under the null conditions of scenario 1. Conclusions: Researchers should account for the ages of a skeletal lesion’s developmental window, where known, when assessing lesion-associated mortality. Survival analyses return accurate results when they exclude in- dividuals in the ages of active lesion formation. Significance: Modeling experiments can identify which archaeologically unmeasurable variables have the greatest impact on estimates of population health and outline the ways in which they bias estimates of past health from the skeletal record. Limitations: The only limits on modeling are limits of imagination and common sense. Suggestions for future research: Many other archaeologically hidden variables remain to be explored with this approach.
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- Award ID(s):
- 2404318
- PAR ID:
- 10656417
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- International Journal of Paleopathology
- Volume:
- 52
- Issue:
- C
- ISSN:
- 1879-9817
- Page Range / eLocation ID:
- 32 to 43
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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