The impact of social experiences of physical and structural violence on the growth of African enslaved children recovered from Lagos, Portugal (15th-17th centuries).

OBJECTIVES: The purpose of this article is to examine the impacts of physical and structural violence on the well-being of early modern enslaved Africans by comparing the growth of children in an archaeological sample recovered from Lagos, Portugal with that of modern children known to have lived under socially oppressive and racist political regimes. MATERIALS AND METHODS: The age of 18 individuals was estimated from the length of developing teeth. Long bone lengths for age in the enslaved African sample were compared with two black juvenile known age samples: the Raymond Dart (South Africa) and Hamann-Todd (United States) collections. Z-scores were calculated for all samples using black children in the South Africa Long Bone (SALB) database as the reference. The similarity of growth across the samples was tested and skeletal growth profiles (SGPs) were devised for the three samples. RESULTS: The children in the Lagos, Raymond Dart, and Hamann-Todd samples were all small for age compared to the SALB reference. While children in the Dart sample tended to be the smallest for age and in the Hamann-Todd the largest, with the children in the Lagos sample falling between them, the three samples did not show significant differences in growth status. DISCUSSION: The growth deficits shown in this study demonstrate the severe impacts of physical and structural violence on the lives of these children. Although uncertainty remains regarding the timing of growth insults relative to arrival, slavery in Portugal as materialized in these individuals was as violent as in other countries.

SPINNE: An app for human vertebral height estimation based on artificial neural networks.

The absence or poor preservation of vertebrae often prevent the application of the anatomical method for stature estimation. The main objective of this paper was to develop a web app based on artificial neural network (ANN) models to estimate the vertebral height of absent or poorly preserved vertebrae from other vertebrae and thus enable the application of anatomical methods. Artificial neural models were developed based on the vertebral height of vertebrae C2 to S1 of a sample composed of 56 adult male and 69 adult female individuals. The skeletons belong to the Identified Skeletal Collection of the University of Coimbra and the ages at death of these individuals ranged from 22 to 58 years old. Statistical analysis and algorithmic development were performed with the R language, R Core Team (2018). Intra- and inter-observer errors regarding the vertebral height were small for all vertebrae (<0.45 mm). Significant models to estimate vertebral height were obtained for both sexes and for the sex-pooled group, although none with an R2 higher than 0.48 and 0.34 for the C2 and the S1, respectively. The root mean square error (RMSE) regarding the predicted vertebral height and the observed vertebral height was almost always smaller than 1.0 mm while most R2 values were higher than 0.6 although models with worse performances were obtained for some vertebrae located at the ends of the vertebral column (C3, L4, and L5). The ANN models have clear potential to predict vertebral height. This mathematical approach may be used to enable the application of the anatomical method for stature estimation when some vertebrae are absent or poorly preserved. The application of the ANN models can be carried out by using the new web based app SPINNE.

Age estimation by pulp/tooth ratio in lateral and central incisors by peri-apical X-ray.

Since 2004, several papers on the analysis of the apposition of secondary dentine have been published. The aim of this paper was to study a sample of peri-apical X-ray images of upper and lower incisors, both lateral and medial, to examine the application of pulp/tooth area ratio as an indicator of age. A sample of 116 individuals, 62 men and 54 women, aged between 18 and 74 years, was studied. Data were fitted with age as a linear function of the pulp/tooth ratio of incisors. The total variance explained by the regression equation ranged from 51.3% of age, when lower lateral incisors were used as explanatory variable, to 81.6% when upper lateral incisors were used. The accuracy of the corresponding regression model yielded ME = 8.44 and 5.34 years, respectively. These results show that, although incisors are less reliable than canines or lower premolars, they can be used to estimate age-at-death when the latter are absent.

Enamel hypoplasias and physiological stress in the Sima de los Huesos Middle Pleistocene hominins.

This study presents an analysis of linear enamel hypoplasias (LEH) and plane-form defects (PFD) in the hominine dental sample from the Sima de los Huesos (SH) Middle Pleistocene site in Atapuerca (Spain). The SH sample comprises 475 teeth, 467 permanent and 8 deciduous, belonging to a minimum of 28 individuals. The method for recording PFD and LEH is discussed, as well as the definition of LEH. The prevalence of LEH and PFD in SH permanent dentition (unilateral total count) is 4.6% (13/280). Only one deciduous tooth (lower dc) showed an enamel disruption. Prevalence by individual ranges from 18.7-30%. The most likely explanation for the relatively low LEH and PFD prevalence in the SH sample suggests that the SH population exhibited a low level of developmental stress. The age at occurrence of LEH and PFD was determined by counting the number of perikymata between each lesion and the cervix of the tooth. Assuming a periodicity of nine days for the incremental lines, the majority of LEH in the SH sample occurred during the third year of life and may be related to the metabolic stress associated with weaning.