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The rules and structure of human culture impact health as much as genetics or environment. To study these relationships, we combine ancient DNA (n=230), skeletal metrics (n=391), paleopathology (n=606), and dietary stable isotopes (n=873) to analyze stature variation in Early Neolithic Europeans from North Central, South Central, Balkan, and Mediterranean regions. In North Central Europe, stable isotopes and linear enamel hypoplasias (LEH) indicate high environmental stress across sexes, but female stature is low, despite polygenic scores identical to males, and suggests cultural factors preferentially supported male recovery from stress. In Mediterranean populations, sexual dimorphism is reduced, indicating male vulnerability to stress and no strong cultural preference for males. Our analysis indicates that biological effects of sex-specific inequities can be linked to cultural influences at least as early as 7000 years ago, and culture, more than environment or genetics, drove height disparities in Early Neolithic Europe. 

We developed a novel method for efficiently estimating time-varying selection coefficients from genome-wide ancient DNA data. In simulations, our method accurately recovers selective trajectories and is robust to misspecification of population size. We applied it to a large data set of ancient and present-day human genomes from Britain and identified seven loci with genome-wide significant evidence of selection in the past 4500 yr. Almost all of them can be related to increased vitamin D or calcium levels, suggesting strong selective pressure on these or related phenotypes. However, the strength of selection on individual loci varied substantially over time, suggesting that cultural or environmental factors moderated the genetic response. Of 28 complex anthropometric and metabolic traits, skin pigmentation was the only one with significant evidence of polygenic selection, further underscoring the importance of phenotypes related to vitamin D. Our approach illustrates the power of ancient DNA to characterize selection in human populations and illuminates the recent evolutionary history of Britain. 

Abstract To elucidate the population history of the Caucasus, we conducted a survey of genetic diversity in Samegrelo (Mingrelia), western Georgia. We collected DNA samples and genealogical information from 485 individuals residing in 30 different locations, the vast majority of whom being Mingrelian speaking. From these DNA samples, we generated mitochondrial DNA (mtDNA) control region sequences for all 485 participants (female and male), Y-short tandem repeat haplotypes for the 372 male participants, and analyzed all samples at nearly 590,000 autosomal single nucleotide polymorphisms (SNPs) plus around 33,000 on the sex chromosomes, with 27,000 SNP removed for missingness, using the GenoChip 2.0+ microarray. The resulting data were compared with those from populations from Anatolia, the Caucasus, the Near East, and Europe. Overall, Mingrelians exhibited considerable mtDNA haplogroup diversity, having high frequencies of common West Eurasian haplogroups (H, HV, I, J, K, N1, R1, R2, T, U, and W. X2) and low frequencies of East Eurasian haplogroups (A, C, D, F, and G). From a Y-chromosome standpoint, Mingrelians possessed a variety of haplogroups, including E1b1b, G2a, I2, J1, J2, L, Q, R1a, and R1b. Analysis of autosomal SNP data further revealed that Mingrelians are genetically homogeneous and cluster with other modern-day South Caucasus populations. When compared with ancient DNA samples from Bronze Age archaeological contexts in the broader region, these data indicate that the Mingrelian gene pool began taking its current form at least by this period, probably in conjunction with the formation of a distinct linguistic community.