Large-scale migration into Britain during the Middle to Late Bronze Age.

Present-day people from England and Wales have more ancestry derived from early European farmers (EEF) than did people of the Early Bronze Age1. To understand this, here we generated genome-wide data from 793 individuals, increasing data from the Middle to the Late Bronze Age and Iron Age in Britain by 12-fold, and western and central Europe by 3.5-fold. Between 1000 and 875 BC, EEF ancestry increased in southern Britain (England and Wales) but not northern Britain (Scotland) due to incorporation of migrants who arrived at this time and over previous centuries, and who were genetically most similar to ancient individuals from France. These migrants contributed about half the ancestry of people of England and Wales from the Iron Age, thereby creating a plausible vector for the spread of early Celtic languages into Britain. These patterns are part of a broader trend of EEF ancestry becoming more similar across central and western Europe in the Middle to the Late Bronze Age, coincident with archaeological evidence of intensified cultural exchange2-6. There was comparatively less gene flow from continental Europe during the Iron Age, and the independent genetic trajectory in Britain is also reflected in the rise of the allele conferring lactase persistence to approximately 50% by this time compared to approximately 7% in central Europe where it rose rapidly in frequency only a millennium later. This suggests that dairy products were used in qualitatively different ways in Britain and in central Europe over this period.

Age-at-Death Estimation for Modern Populations in Mexico and Puerto Rico through the Use of 3D Laser Scans of the Pubic Symphysis.

Reliable age-at-death estimates from the adult skeleton are of fundamental importance in forensic anthropology, because it contributes to the identity parameters used in a medicolegal death investigation. However, reliable estimates are difficult because many traditional aging methods depend on a set of population-specific criteria derived from individuals of European and African descent. The absence of information on the potential differences in the aging patterns of underrepresented, especially Latinx, populations may hinder our efforts to produce useful age-at-death estimates. In response to these concerns, this study explores the utility of currently available aging techniques and whether population-specific aging methods among Latinx groups are needed. The authors obtained data from two skeletal collections representing modern individuals of Mexican and Puerto Rican origin. They examined five newly developed computational shape-based techniques using 3D laser scans of the pubic symphysis and one traditional bone-to-phase technique. A validation test of all computational and traditional methods was implemented, and new population-specific equations using the computational algorithms were generated and tested against a subsample. Results suggest that traditional and computational aging techniques applied to the pubic symphysis perform best with individuals within 35-45 years of age. Levels of bias and inaccuracy increase as chronological age increases, with overestimation of individuals younger than 35 years and underestimation of individuals older than 45 years. New regression models provided error rates comparable to, and in some occasions outperformed, the original computational models developed on white American males, but age estimates did not significantly improve. This study shows that population-specific models do not necessarily improve age estimates in Latinx samples. Results do suggest that computational methods can ultimately outperform the Suchey-Brooks method and provide improved objectivity when estimating age at death in Latinx samples.