Ancient Native Americans Research Articles

Spatiotemporal fluctuations of population structure in the Americas revealed by a meta-analysis of the first decade of archaeogenomes.

Since 2010, genome-wide data from hundreds of ancient Native Americans have contributed to the understanding of Americas' prehistory. However, these samples have never been studied as a single dataset, and distinct relationships among themselves and with present-day populations may have never come to light. Here, we reassess genomic diversity and population structure of 223 ancient Native Americans published between 2010 and 2019. The genomic data from ancient Americas was merged with a worldwide reference panel of 278 present-day genomes from the Simons Genome Diversity Project and then analyzed through ADMIXTURE, D-statistics, PCA, t-SNE, and UMAP. We find largely similar population structures in ancient and present-day Americas. However, the population structure of contemporary Native Americans, traced here to at least 10,000 years before present, is noticeably less diverse than their ancient counterparts, a possible outcome of the European contact. Additionally, in the past there were greater levels of population structure in North than in South America, except for ancient Brazil, which harbors comparatively high degrees of structure. Moreover, we find a component of genetic ancestry in the ancient dataset that is closely related to that of present-day Oceanic populations but does not correspond to the previously reported Australasian signal. Lastly, we report an expansion of the Ancient Beringian ancestry, previously reported for only one sample. Overall, our findings support a complex scenario for the settlement of the Americas, accommodating the occurrence of founder effects and the emergence of ancestral mixing events at the regional level.

The Storied Landscape of Iroquoia: History, Conquest, and Memory in the Native Northeast

The Storied Landscape of Iroquoia: History, Conquest, and Memory in the Native Northeast

Ancient Native Americans were among the world’s first coppersmiths

Ancient Native Americans were among the world’s first coppersmiths

Cranial and Postcranial Metric Sex Estimation in Modern Thai and Ancient Native American Individuals

Historically, morphometric standards used in forensic anthropology and bioarchaeology were derived from individuals of African and European descent, along with ancient Native Americans. However, it is unlikely that these standards can be accurately applied to modern Asian populations, and they may introduce error into biological profiles. Due to different population histories, it is hypothesized that ancient Native American and modern Thai individuals are morphometrically distinct. This study investigates the differences in sexual dimorphism between 102 Native American adults and 100 Thai individuals, 17 to 96 years old. A total of 30 cranial, 8 mandibular, and 58 postcranial measurements were compared between the two groups. Using independent t-tests, MANOVAs, univariate sectioning points, and linear discriminant functions, the Native American and Thai samples were found to be significantly different in the expression of sexual dimorphism for many elements. Further, measurements tested in Spradley and Jantz’s (2011) American Black and American White discriminant function equations produce correct classification biases of –91.0–100.0% and often fail to correctly classify Native American and Thai individuals. Therefore, the metric sex estimation methods developed on non-Asian populations do not adequately classify Native American and Thai individuals, thereby underscoring the importance of population-specific equations. The population-specific statistics developed for the Native Americans correctly classify 48.1–93.8% (univariate) and 70.8–94.1% (multivariate) of individuals, while those developed for the Thai correctly classify 47.8–93.0% (univariate) and 63.2–100.0% (multivariate). The most discriminating elements are population dependent: the humerus, clavicle, and tibia work best for Native Americans, while the os coxa, ulna, and scapula perform best for Thai individuals.

Terminal Pleistocene Alaskan genome reveals first founding population of Native Americans.

Despite broad agreement that the Americas were initially populated via Beringia, the land bridge that connected far northeast Asia with northwestern North America during the Pleistocene epoch, when and how the peopling of the Americas occurred remains unresolved. Analyses of human remains from Late Pleistocene Alaska are important to resolving the timing and dispersal of these populations. The remains of two infants were recovered at Upward Sun River (USR), and have been dated to around 11.5 thousand years ago (ka). Here, by sequencing the USR1 genome to an average coverage of approximately 17 times, we show that USR1 is most closely related to Native Americans, but falls basal to all previously sequenced contemporary and ancient Native Americans. As such, USR1 represents a distinct Ancient Beringian population. Using demographic modelling, we infer that the Ancient Beringian population and ancestors of other Native Americans descended from a single founding population that initially split from East Asians around 36 ± 1.5 ka, with gene flow persisting until around 25 ± 1.1 ka. Gene flow from ancient north Eurasians into all Native Americans took place 25-20 ka, with Ancient Beringians branching off around 22-18.1 ka. Our findings support a long-term genetic structure in ancestral Native Americans, consistent with the Beringian 'standstill model'. We show that the basal northern and southern Native American branches, to which all other Native Americans belong, diverged around 17.5-14.6 ka, and that this probably occurred south of the North American ice sheets. We also show that after 11.5 ka, some of the northern Native American populations received gene flow from a Siberian population most closely related to Koryaks, but not Palaeo-Eskimos, Inuits or Kets, and that Native American gene flow into Inuits was through northern and not southern Native American groups. Our findings further suggest that the far-northern North American presence of northern Native Americans is from a back migration that replaced or absorbed the initial founding population of Ancient Beringians.

Genetic signature of natural selection in first Americans

When humans moved from Asia toward the Americas over 18,000 y ago and eventually peopled the New World they encountered a new environment with extreme climate conditions and distinct dietary resources. These environmental and dietary pressures may have led to instances of genetic adaptation with the potential to influence the phenotypic variation in extant Native American populations. An example of such an event is the evolution of the fatty acid desaturases (FADS) genes, which have been claimed to harbor signals of positive selection in Inuit populations due to adaptation to the cold Greenland Arctic climate and to a protein-rich diet. Because there was evidence of intercontinental variation in this genetic region, with indications of positive selection for its variants, we decided to compare the Inuit findings with other Native American data. Here, we use several lines of evidence to show that the signal of FADS-positive selection is not restricted to the Arctic but instead is broadly observed throughout the Americas. The shared signature of selection among populations living in such a diverse range of environments is likely due to a single and strong instance of local adaptation that took place in the common ancestral population before their entrance into the New World. These first Americans peopled the whole continent and spread this adaptive variant across a diverse set of environments.

Origin Stories, Archaeological Evidence, and Postclovis Paleoindian Bison Hunting on the Great Plains

Reconstructions of the Paleoindian period are archaeology's origin stories about the native people of North America. These reconstructions have strongly emphasized great differences between recent and ancient Native Americans, echoing a perspective with its roots in the nineteenth century. One central component of the differences archaeologists have seen lies in the way that Paleoindian groups moved across the landscape. Particularly on the Great Plains, these movements have been seen as unpredictable and nonrepetitive, with this view founded largely in interpretations of evidence from large bison kills. This paper compares the overall patterns of post-Clovis Paleoindian and post-Paleoindian communal bison hunting on the Plains, arguing that there is no evidence of rapid or substantial change in such hunting at the end of the Paleoindian period. Although hunting practices did not remain exactly the same over time, most of the basic characteristics of Paleoindian hunting were common on the Plains for millennia. Only the northern Plains stands out from this, and it does so only within the last 2,000 to 3,000 years, probably in reaction to the development of continent-wide exchange networks. Paleoindians certainly lived different lives than did later occupants of the Great Plains, but the literature significantly exaggerates the magnitude of this difference.

Sexing skulls using discriminant function analysis of visually assessed traits

The accuracy of sex determinations based on visual assessments of the mental eminence, orbital margin, glabellar area, nuchal area, and mastoid process was tested on a series of 304 skulls of known age and sex from people of European American, African American, and English ancestry as well as on an ancient Native American sample of 156 individuals whose sex could be reliably determined based on pelvic morphology. Ordinal scores of these sexually dimorphic traits were used to compute sex determination discriminant functions. Linear, kth-nearest-neighbor, logistic, and quadratic discriminant analysis models were evaluated based on their capacity to minimize both misclassifications and sex biases in classification errors. Logistic regression discriminant analysis produced the best results: a logistic model containing all five cranial trait scores correctly classified 88% of the modern skulls with a negligible sex bias of 0.1%. Adding age at death, birth year, and population affinity to the model did not appreciably improve its performance. For the ancient Native American sample, the best logistic regression model assigned the correct pelvic sex to 78% of the individuals with a sex bias of only 0.2%. Similar cranial trait frequency distributions were found in same-sex comparisons of the modern African American, European American, and English samples. The sexual dimorphism of these modern people contrasts markedly with that of the ancient Native Americans. Because of such population differences, discriminant functions like those presented in this paper should be used with caution on populations other than those for which they were developed.

Ancient Native Americans

Ancient Native Americans