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Objectives Intraspecific shape variation in the recent Homo sapiens bony labyrinth has been assessed for association with sexual dimorphism, body size, and genetic differences, but has not been fully assessed for association with extrinsic factors, such as subsistence strategy and climate. While the skull overall is known to vary with these variables, the bony labyrinth develops in utero and exhibits microstructural stability through adulthood. Therefore, labyrinthine morphology may be resistant to extrinsic variables.Materials and methods We collected labyrinthine shape data using computed tomography from 262 individuals associated with archeological or contemporary collections used for dissection in North America, Europe, Africa, and Southeast Asia. We assessed the data for observer error and asymmetry. Shape variation is examined between subsistence strategy groups and climate type groups with Principal Components Analyses and Procrustes ANOVA's, and shape variation was correlated with specific climate data (precipitation, temperature, altitude) with a two-block partial least squares analysis. Results Both inter- and intra-observer error as well as asymmetry minimally affected labyrinthine shape variation. We found that both subsistence strategy and climate each account for a statistically significant 7% of overall shape variation, and that specific climate variables have statistically significant correlation with labyrinthine shape variation (RV 0.52527). Discussion Morphological variation in this sample indicates that the labyrinth is not entirely resistant to extrinsic factors associated with subsistence strategy and climate. Shape differences are not localized to specific regions of the labyrinth, but may contribute to the complicated variation seen in recent human evolution and warrants further exploration. 1 Introduction 2 Materials and methods 2.1 | Data acquisition and formatting 2.2 | Preliminary analyses 3 Results 3.1 | Preliminary analyses 3.2 | Main analyses 4 Discussion

Stature estimation from the skeleton is a classic anthropological problem, and recent years have seen the proliferation of population-specific regression equations. Many rely on the anatomical reconstruction of stature from archaeological skeletons to derive regression equations based on long bone lengths, but this requires a collection with very good preservation. In some regions, for example, South Asia, typical environmental conditions preclude the sufficient preservation of skeletal remains. Large-scale epidemiological studies that include medical imaging of the skeleton by techniques such as dual-energy X-ray absorptiometry (DXA) offer new potential datasets for developing such equations. \ud \ud We derived estimation equations based on known height and bone lengths measured from DXA scans from the Andhra Pradesh Children and Parents Study (Hyderabad, India). Given debates on the most appropriate regression model to use, multiple methods were compared, and the performance of the equations was tested on a published skeletal dataset of individuals with known stature. \ud \ud The equations have standard errors of estimates and prediction errors similar to those derived using anatomical reconstruction or from cadaveric datasets. As measured by the number of significant differences between true and estimated stature, and the prediction errors, the new equations perform as well as, and generally better than, published equations commonly used on South Asian skeletons or based on Indian cadaveric datasets. \ud \ud This study demonstrates the utility of DXA scans as a data source for developing stature estimation equations and offer a new set of equations for use with South Asian datasets.

Objectives: Native Andean ancestry gives partial protection from reduced birthweight at high altitude in the Andes compared with European ancestry. Whether Andean ancestry is also associated with body proportions and greater postnatal body size at altitude is unknown. Therefore, we tested whether a greater proportion of Andean ancestry is associated with stature and body proportions among Peruvian children at high and low altitude.\ud Methods: Height, head circumference, head-trunk height, upper and lower limb lengths, and tibia, ulna, hand and foot lengths, were measured in 133 highland and 169 lowland children aged 6 months to 8.5 years. For highland and lowland groups separately, age-sex-adjusted anthropometry z scores were regressed on the number of indigenous parental surnames as a proxy for Andean ancestry, adjusting for potential confounders (maternal age and education, parity, altitude [highlands only]).\ud Results: Among highland children, greater Andean ancestry was negatively associated with stature and tibia, ulna, and lower limb lengths, independent of negative associations with greater altitude for these measurements. Relationships were strongest for tibia length: each additional Andean surname or 1,000 m increase at altitude among highland children was associated with 0.18 and 0.65 z score decreases in tibia length, respectively. Anthropometry was not significantly associated with ancestry among lowland children.\ud Conclusions: Greater Andean ancestry is associated with shorter stature and limb measurements at high but not low altitude. Gene-environment interactions between high altitude and Andean ancestry may exacerbate the trade-off between chest dimensions and stature that was proposed previously, though we could not test this directly.

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Shanidar Cave in Iraqi Kurdistan became an iconic Palaeolithic site after Ralph Solecki’s discoveries in 1951-1960 of 10 Neanderthals, some of whom he argued had died in rockfalls and others–controversially–buried with formal burial rites, including one with flowers. New excavations began in 2015. In 2018 the team discovered the articulated upper body of an adult Neanderthal near to the ‘Flower Burial’ location, dating to 70–60 thousand years ago. Stratigraphic evidence suggests that it was a deliberate burial. The new find is the first articulated Neanderthal discovered for some 35 years, so of considerable potential importance for Neanderthal studies.