Dogs were present in the Americas before the arrival of European colonists, but the origin and fate of these precontact dogs are largely unknown. We sequenced 71 mitochondrial and 7 nuclear genomes from ancient North American and Siberian dogs from time frames spanning ~9000 years. Our analysis indicates that American dogs were not derived from North American wolves. Instead, American dogs form a monophyletic lineage that likely originated in Siberia and dispersed into the Americas alongside people. After the arrival of Europeans, native American dogs almost completely disappeared, leaving a minimal genetic legacy in modern dog populations. The closest detectable extant lineage to precontact American dogs is the canine transmissible venereal tumor, a contagious cancer clone derived from an individual dog that lived up to 8000 years ago.

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Adult stature variation is commonly attributed to differential stress-levels during development. However, due to selective mortality and heterogeneous frailty, a population's tall stature may be more indicative of high selective pressures than of positive life conditions. This article examines stature in a biocultural context and draws parallels between bioarchaeological and living populations to explore the multidimensionality of stature variation in the past. This study investigates: 1) stature differences between archaeological populations exposed to low or high stress (inferred from skeletal indicators); 2) similarities in growth retardation patterns between archaeological and living groups; and 3) the apportionment of variance in growth outcomes at the regional level in archaeological and living populations. Anatomical stature estimates were examined in relation to skeletal stress indicators (cribra orbitalia, porotic hyperostosis, linear enamel hypoplasia) in two medieval bioarchaeological populations. Stature and biocultural information were gathered for comparative living samples from South America. Results indicate 1) significant (P < 0.01) differences in stature between groups exposed to different levels of skeletal stress; 2) greater prevalence of stunting among living groups, with similar patterns in socially stratified archaeological and modern groups; and 3) a degree of regional variance in growth outcomes consistent with that observed for highly selected traits. The relationship between early stress and growth is confounded by several factors-including catch-up growth, cultural buffering, and social inequality. The interpretations of early life conditions based on the relationship between stress and stature should be advanced with caution. Am J Phys Anthropol 155: 229-242, 2014.

The phenotypic expression of adult body size and shape results from synergistic interactions between hereditary factors and environmental conditions experienced during growth. Variation in body size and shape occurs even in genetically relatively homogeneous groups, due to different occurrence, duration, and timing of growth insults. Understanding the causes and patterns of intrapopulation variation can foster meaningful information on early life conditions in living and past populations. This study assesses the pattern of biological variation in body size and shape attributable to sex and social status in a medieval Italian population. The sample includes 52 (20 female, 32 male) adult individuals from the medieval population of Trino Vercellese, Italy. Differences in element size and overall body size (skeletal height and body mass) were assessed through Monte Carlo methods, while univariate non-parametric tests and Principal Component Analysis (PCA) were employed to examine segmental and overall body proportions. Discriminant Analysis was employed to determine the predictive value of individual skeletal elements for social status in the population. Our results highlight a distinct pattern in body size and shape variation in relation to status and sex. Male subsamples exhibit significant postcranial variation in body size, while female subsamples express smaller, nonsignificant differences. The analysis of segmental proportions highlighted differences in trunk/lower limb proportions between different status samples, and PCA indicated that in terms of purely morphological variation high status males were distinct from all other groups. The pattern observed likely resulted from a combination of biological factors and cultural practices.

Variation in limb proportions between prehistoric Jomon and Yayoi people of Japan are explored by this study. Jomon people were the descendents of Pleistocene nomads who migrated to the Japanese Islands around 30,000 yBP. Phenotypic and genotypic evidence indicates that Yayoi people were recent migrants to Japan from continental Northeast Asia who likely interbred with Jomon foragers. Limb proportions of Jomon and Yayoi people were compared using RMA regression and "Quick-Test" calculations to investigate relative variability between these two groups. Cluster and principal components analyses were performed on size-standardized limb lengths and used to compare Jomon and Yayoi people with other groups from various climatic zones. Elongated distal relative to proximal limb lengths were observed among Jomon compared to Yayoi people. Jomon limb proportions were similar to human groups from temperate/tropical climates at lower latitudes, while Yayoi limb proportions more closely resemble groups from colder climates at higher latitudes. Limb proportional similarities with groups from warmer environments among Jomon foragers likely reflect morphological changes following Pleistocene colonization of the Japanese Islands. Cold-derived limb proportions among the Yayoi people likely indicate retention of these traits following comparatively recent migrations to the Japanese Islands. Changes in limb proportions experienced by Jomon foragers and retention of cold-derived limb proportions among Yayoi people conform to previous findings that report changes in these proportions following long-standing evolution in a specific environment.