Secular decline in cranioskeletal size over two millennia of interior central California prehistory: Relation to calcium deficit in the reconstructed diet and demographic stress

An osteometric study of residual rickets (RR) skeletal plasticity has been made of a time-ordered sequence of fifteen series of adult skeleton sets (n=359) from the Great Valley of central California (GV), spanning the three archaeological horizons of California Indian prehistory in this region: Early (EH), Middle (MH) and Late (LH). By least-squares linear regression analysis, a clear and continuous downward trend obtained in cranioskeletal size in both sexes, proceeding from EH to LH in the GV sequence, pari passu with a steady upward trend in the RR-15 score. To ascertain if dietary calcium deficit (CADEF), a known cause of active rickets, can explain the observed secular increase in RR, the aboriginal diet was reconstructed by the diet grid method: CADEF was found to rise from borderline in the EH, to moderate in the MH, to severe in the LH, as the subsistence base shifted gradually away from hunted prey, and storable seed foods—mainly leached acorn meal—became the dominant source of energy. Further regression analysis has shown that the secular upward trend in CADEF is highly correlated with the temporal clines of the GV sequence, directly with the RR-15 score, and inversely with cranioskeletal size: in round numbers, one grade of CADEF brings about a loss of 120 cm³ or 4 per cent in partial skeleton volume. Two biocultural influences—demographic stress (DS) in females, and the less common ‘male nutritional advantage interaction co-factor’ (MNAIC)—modulate the primary bone antitrophic CADEF effect: DS enhancing, MNAIC ameliorating.     

Combined application of pansharpening and enhancement methods to improve archaeological cropmark visibility and identification in QuickBird imagery: two case studies from Apulia,Southern Italy

Launch of Very High Resolution (VHR) satellite sensors meant a significant evolution for Remote Sensing archaeological applications since data with high spatial resolution may be used to identify signals related to buried archaeological remains (e.g. cropmarks, soilmarks, dampmarks) in very extended territories. The aim of this work is to develop a suitable image processing workflow to improve the cropmark visibility in the VHR satellite images. The workflow implemented consists of two steps: first the panchromatic and multispectral images have been pansharpened in order to merge the two images, then some Enhancement methods have been applied on the pansharpened image. As a result of the several tested pansharpening techniques, the Principal Component Resolution Merge yields images of very good quality useful not only for visualization but also as input for further processing. Among the different enhancement methods taken into consideration, the Spatial Enhancement, carried out by applying the Wallis Adaptive filter further improve the visibility and recognition of the archaeological signals.     

Computed femur and tibia volumes and cranial capacity under near-optimal conditions of skeletal growth: Relation to geomagnetic dipole field intensity and other latitude-dependent climatic variables in archaeological North America and North Africa

Using computed femur (F) and tibia (T) volumes and cranial capacity (CC), the Pleistocene geomagnetic acromegalosis (PGMA) model of human evolution is tested in eight series of male skeleton sets (n = 123) from aboriginal North America and North Africa, the majority dated to the Holocene. The material was selected from the extensive multiracial osteometric data base previously assembled in the course of adult residual rickets (RR) skeletal plasticity research in archaeological populations of the Northern Hemisphere, controlling for optimal bone eutrophism, that is, for the absence of sunshine and calcium deficits and demographic stress. Six of the eight series are of hunter-gatherers, including a terminal Pleistocene mesolithic sample from the Maghreb. As predicted by PGMA, a clear osteotrophic response is observed between the F, T, and CC of these populations and their geomagnetic dipole field intensity (GMFI) backgrounds, here expressed in microteslas (μT); along with evidence that the GMFI-dependent osteotrophism is stronger near the sagittal plane. Slightly higher bioenvironmental correlations, also compatible with PGMA, are obtained with a composite environmental osteotrophism parameter (CEOT.J), which incorporates the reciprocal of the archaeological site's reconstructed mean July temperature as a synergizer of GMFI. In a final demonstration of the utility of the new computed osteovolumetrics, it is shown that Skhul IV, to judge from its size and proportions, is a hyperrobust pre-neanderthal male skeleton of early Late Pleistocene interglacial age, and belongs to the North African geographical race.