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Abstract ObjectivesWe 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 MethodsWe 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. ResultsUnar 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. DiscussionThese 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 HighlightsAdult 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.
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Allometric scaling and growth: Evaluation and applications in subadult body mass estimation
Abstract ObjectivesPreviously developed methods in subadult body mass estimation have not been tested in populations other than European–American or African–American. This study uses a contemporary Taiwanese sample to test these methods. Through evaluating their accuracy and bias, we addressed whether the allometric relationships between body mass and skeletal traits commonly used in subadult body mass estimation are conserved among different populations. Materials and MethodsComputed tomography scans of lower limbs from individuals aged 0–17 years old of both sexes were collected from National Taiwan University Hospital along with documented body weight. Polar second moment of area, distal femoral metaphyseal breadth, and maximum superior/inferior femoral head diameter were collected either directly from the scans or from reconstructed 3D models. Estimated body mass was compared with documented body mass to assess the performance of the equations. ResultsCurrent methods provided good body mass estimates in Taiwanese individuals, with accuracy and bias similar to those reported in other validation studies. A tendency for increasing error with increasing age was observed for all methods. Reduced major axis regression showed the allometric relationships between different skeletal traits and body mass across different age categories can all be summarized using a common fitted line. A revised, maximum likelihood‐based approach was proposed for all skeletal traits. DiscussionThe results suggested that the allometric relationships between body mass and different skeletal traits are largely conserved among populations. The revised method provided improved applicability with strong underlying theoretical justifications, and potential for future improvements.
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- Award ID(s):
- 1945797
- PAR ID:
- 10367412
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- American Journal of Physical Anthropology
- Volume:
- 175
- Issue:
- 3
- ISSN:
- 0002-9483
- Page Range / eLocation ID:
- p. 577-588
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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