Beringian Standstill Research Articles

Archaeological Artifacts from the Stone Age Solve the Mystery of the First Native Americans

Many scholars have sought to uncover the mysteries relating to the origins of the earliest Native Americans. Among many hypotheses, the Beringian Standstill Hypothesis and the Kelp Highway Hypothesis claim that the first Native Americans stayed in Beringia during the Last Glacial Maximum, before migrating to the New World by boat as the climate warmed. Unfortunately, neither hypothesis was devised with tangible supporting evidence, such as archaeological artifacts; as such, both remain controversial. To address this issue, this paper compares and analyzes the genetic data related to the first Native Americans and the data of six archaeological artifacts from the Stone Age. The results show that both hypotheses are correct, but the first Native Americans stayed in Southern Korea rather than Beringia on their journey to America. Genetic and archaeological data converge to show the first Native Americans came from Southern Korea.

Post-last glacial maximum expansion of Y-chromosome haplogroup C2a-L1373 in northern Asia and its implications for the origin of Native Americans.

Subbranches of Y-chromosome haplogroup C2a-L1373 are founding paternal lineages in northern Asia and Native American populations. Our objective was to investigate C2a-L1373 differentiation in northern Asia and its implications for Native American origins. Sequences of rare subbranches (n = 43) and ancient individuals (n = 37) of C2a-L1373 (including P39 and MPB373), were used to construct phylogenetic trees with age estimation by BEAST software. C2a-L1373 expanded rapidly approximately 17.7,000-14.3,000 years ago (kya) after the last glacial maximum (LGM), generating numerous sublineages which became founding paternal lineages of modern northern Asian and Native American populations (C2a-P39 and C2a-MPB373). The divergence pattern supports possible initiation of differentiation in low latitude regions of northern Asia and northward diffusion after the LGM. There is a substantial gap between the divergence times of C2a-MPB373 (approximately 22.4 or 17.7 kya) and C2a-P39 (approximately 14.3 kya), indicating two possible migration waves. We discussed the decreasing time interval of "Beringian standstill" (2.5 ky or smaller) and its reduced significance. We also discussed the multiple possibilities for the peopling of the Americas: the "Long-term Beringian standstill model," the "Short-term Beringian standstill model," and the "Multiple waves of migration model." Our results support the argument from ancient DNA analyses that the direct ancestor group of Native Americans is an admixture of "Ancient Northern Siberians" and Paleolithic communities from the Amur region, which appeared during the post-LGM era, rather than ancient populations in greater Beringia, or an adjacent region, before the LGM.

Alaskan Lake Sediment Records and Their Implications for the Beringian Standstill Hypothesis

ABSTRACT Recent analyses of lake sediments in Alaska have provided physical evidence supporting the genetically inferred Beringian Standstill Hypothesis and insight into the location of its occurrence. However, the biomarkers analyzed in these sediments are relatively novel paleoenvironmental proxies, so their reliability is understandably scrutinized. Further, the timing of human presence inferred from these sediments predates the oldest, unequivocal archaeological artifacts in Alaska. In this Perspective essay, I discuss the interpretation, limitations, and implications of the sedimentary analyses. Additionally, I explore the archaeological dilemma that they pose.

Sedimentary biomarkers reaffirm human impacts on northern Beringian ecosystems during the Last Glacial period

Our understanding of the timing of human arrival to the Americas remains fragmented, despite decades of active research and debate. Genetic research has recently led to the ‘Beringian standstill hypothesis’ (BSH), which suggests an isolated group of humans lived somewhere in Beringia for millennia during the Last Glacial, before a subgroup migrated southward into the American continents about 14 ka. Recently published organic geochemical data suggest human presence around Lake E5 on the Alaskan North Slope during the Last Glacial; however, these biomarker proxies, namely faecal sterols and polycyclic aromatic hydrocarbons (PAHs), are relatively novel and require replication to bolster their support of the BSH. We present new analyses of these biomarkers in the sediment archive of Burial Lake (latitude 68°26′N, longitude 159°10′W m a.s.l.) in northwestern Alaska. Our analyses corroborate that humans were present in Beringia during the Last Glacial and that they likely promoted fire activity. Our data also suggest that humans coexisted with Ice Age megafauna for millennia prior to their eventual extinction at the end of the Last Glacial. Lastly, we identify fire as an overlooked ecological component of the mammoth steppe ecosystem.

Y Chromosome Sequences Reveal a Short Beringian Standstill, Rapid Expansion, and early Population structure of Native American Founders

The Americas were the last inhabitable continents to be occupied by humans, with a growing multidisciplinary consensus for entry 15-25 thousand years ago (kya) from northeast Asia via the former Beringia land bridge [1-4]. Autosomal DNA analyses have dated the separation of Native American ancestors from the Asian gene pool to 23 kya or later [5, 6] andmtDNA analyses to ∼25 kya [7], followed by isolation ("Beringian Standstill" [8, 9]) for 2.4-9 ky and then arapid expansion throughout the Americas. Here, we present a calibrated sequence-based analysis of222 Native American and relevant Eurasian Ychromosomes (24 new) from haplogroups Q andC [10], with four major conclusions. First, we identify three to four independent lineages as autochthonous and likely founders: the major Q-M3 and rarer Q-CTS1780 present throughout the Americas, the very rare C3-MPB373 in South America, and possibly the C3-P39/Z30536 in North America. Second, from the divergence times and Eurasian/Americandistribution of lineages, we estimate a Beringian Standstill duration of 2.7 ky or 4.6 ky, according to alternative models, and entry south of the ice sheet after 19.5 kya. Third, we describe thestar-like expansion of Q-M848 (within Q-M3) starting at 15 kya [11] in the Americas, followed by establishment of substantial spatial structure in South Americaby 12 kya. Fourth, the deep branches of theQ-CTS1780 lineage present at low frequencies throughout the Americas today [12] may reflect a separate out-of-Beringia dispersal after the melting of the glaciers at the end of the Pleistocene.

Evidence of Ice Age humans in eastern Beringia suggests early migration to North America

Our understanding of the timing and pathway of human arrival to the Americas remains an important and polarizing topic of debate in archaeology and anthropology. Traditional consensus, supported by archaeological and paleoenvironmental data, favors a ‘swift peopling’ of the Americas from Asia via the Bering Land Bridge during the last Glacial termination. More recent genetic data and archaeological finds have challenged this view, proposing the ‘Beringian standstill hypothesis’ (BSH), wherein a population of proto-Americans migrated from Asia during, or even prior to the Last Glacial Maximum (LGM) and lived in Beringia for thousands of years before their eventual spread across the American continents. Using a sediment archive from Lake E5 (68.641667° N, 149.457706° W), located on Alaska's North Slope, we present new data supporting the BSH and shedding new light on the environmental impact of these early American populations. Fecal biomarkers support human presence in the environs of the lake, and our data demonstrate elevated biomass burning in this region during the last Glacial. Elevated burning defies the expectation that natural fires would be less frequent in the Arctic during the last Glacial, thereby suggesting human ignition as the likely culprit. Our data shed new light on the pathway and timing of human migration to the Americas and demonstrate the possibility of the sustainable coexistence of humans and the Ice Age megafauna in Beringia prior to their extinction.

Paternal origin of Paleo-Indians in Siberia: insights from Y-chromosome sequences.

The expansion of modern humans to the American continent after the Last Glacial Maximum led the way to the present-day distribution of American aborigines. Recent advances in autosomal DNA research and expanded testing of mtDNA lineages has provided a clearer picture of the number and timing of founding lineages. However, both autosomal DNA and mtDNA research have provided unresolved competing theories between the short-term and the long-term models of the Beringian standstill hypothesis. Further, the source of founding paternal lineages of American aborigines and their relationship with ancient Siberia populations remains ambiguous. In this study, we reanalyzed a 7.0 Mbp region of 132 paternal Y-chromosome sequences, including 39 newly reported ones, of male samples from American aborigines and Eurasian populations. Among Eurasian samples, we identified Y-chromosome branches that are most closely related to known American aborigine founding lineages, that is, Q1-L804 links to Q1-M3, Q1-L330 links to Q1-Z780, Q1-M120 links to Q1-B143, and C2-F1756 links to C2-P39. The revised phylogenetic tree and age estimates indicate a narrow timeframe (~15.3-14.3 kya) for the upper time limit of human entry to the American continent. Our analysis suggests that the in situ differentiation of Q-M242 in Central Eurasia and South Siberia region gave rise to numerous sub-lineages older than 15.3 kya, and the founding of Paleo-Indian paternal lineages is part of the great Q1-L53 diffusion throughout the Eurasia after the Last Glacial Maximum. The results of our study will assist in future studies of the history of modern populations in Eurasia and the Americas.

Human Dispersal from Siberia to Beringia

With genetic studies showing unquestionable Asian origins of the first Americans, the Siberian and Beringian archaeological records are absolutely critical for understanding the initial dispersal of modern humans in the Western Hemisphere. The genetics-based Beringian Standstill Model posits a three-stage dispersal process and necessitates several expectations of the archaeological record of northeastern Asia. Here we present an overview of the Siberian and Beringian Upper Paleolithic records and discuss them in the context of a Beringian Standstill. We report that not every expectation of the model is met with archaeological data at hand.

Human Colonization of Asia in the Late Pleistocene

Human Colonization of Asia in the Late Pleistocene

Earliest Human Presence in North America Dated to the Last Glacial Maximum: New Radiocarbon Dates from Bluefish Caves, Canada.

The timing of the first entry of humans into North America is still hotly debated within the scientific community. Excavations conducted at Bluefish Caves (Yukon Territory) from 1977 to 1987 yielded a series of radiocarbon dates that led archaeologists to propose that the initial dispersal of human groups into Eastern Beringia (Alaska and the Yukon Territory) occurred during the Last Glacial Maximum (LGM). This hypothesis proved highly controversial in the absence of other sites of similar age and concerns about the stratigraphy and anthropogenic signature of the bone assemblages that yielded the dates. The weight of the available archaeological evidence suggests that the first peopling of North America occurred ca. 14,000 cal BP (calibrated years Before Present), i.e., well after the LGM. Here, we report new AMS radiocarbon dates obtained on cut-marked bone samples identified during a comprehensive taphonomic analysis of the Bluefish Caves fauna. Our results demonstrate that humans occupied the site as early as 24,000 cal BP (19,650 ± 130 14C BP). In addition to proving that Bluefish Caves is the oldest known archaeological site in North America, the results offer archaeological support for the “Beringian standstill hypothesis”, which proposes that a genetically isolated human population persisted in Beringia during the LGM and dispersed from there to North and South America during the post-LGM period.

Sinodonty, Sundadonty, and the Beringian Standstill model: Issues of timing and migrations into the New World

C.G. Turner II made dental morphological observations on thousands of Eskimo-Aleuts and American Indians and concluded they were derived from ancestral populations in northeast Asia during the last stages of the Pleistocene. He further distinguished two dental patterns in Asia. In East Asia, populations exhibit Sinodonty, a specialized dentition with intensified trait expressions. Southeast Asians exhibit Sundadonty, a more generalized dentition for crown and root traits. Turner argued all New World groups were derived from Sinodonts. Recent work has led some researchers to conclude there is evidence for the Sundadont pattern in Native American populations, an observation in accord with craniometric research that argues for an early migration of a generalized Asian population, followed by an influx of more specialized northeast Asians. A reanalysis of Turner's dataset fails to reveal evidence for a Sundadont component in the settlement of the Americas, but it does provide support for the Beringian Standstill model proposed by geneticists.

Beringia and the global dispersal of modern humans.

Until recently, the settlement of the Americas seemed largely divorced from the out-of-Africa dispersal of anatomically modern humans, which began at least 50,000 years ago. Native Americans were thought to represent a small subset of the Eurasian population that migrated to the Western Hemisphere less than 15,000 years ago. Archeological discoveries since 2000 reveal, however, that Homo sapiens occupied the high-latitude region between Northeast Asia and northwest North America (that is, Beringia) before 30,000 years ago and the Last Glacial Maximum (LGM). The settlement of Beringia now appears to have been part of modern human dispersal in northern Eurasia. A 2007 model, the Beringian Standstill Hypothesis, which is based on analysis of mitochondrial DNA (mtDNA) in living people, derives Native Americans from a population that occupied Beringia during the LGM. The model suggests a parallel between ancestral Native Americans and modern human populations that retreated to refugia in other parts of the world during the arid LGM. It is supported by evidence of comparatively mild climates and rich biota in south-central Beringia at this time (30,000-15,000 years ago). These and other developments suggest that the settlement of the Americas may be integrated with the global dispersal of modern humans.

Two contemporaneous mitogenomes from terminal Pleistocene burials in eastern Beringia

Pleistocene residential sites with multiple contemporaneous human burials are extremely rare in the Americas. We report mitochondrial genomic variation in the first multiple mitochondrial genomes from a single prehistoric population: two infant burials (USR1 and USR2) from a common interment at the Upward Sun River Site in central Alaska dating to ∼11,500 cal B.P. Using a targeted capture method and next-generation sequencing, we determined that the USR1 infant possessed variants that define mitochondrial lineage C1b, whereas the USR2 genome falls at the root of lineage B2, allowing us to refine younger coalescence age estimates for these two clades. C1b and B2 are rare to absent in modern populations of northern North America. Documentation of these lineages at this location in the Late Pleistocene provides evidence for the extent of mitochondrial diversity in early Beringian populations, which supports the expectations of the Beringian Standstill Model.

Beringian Standstill and Spread of Native American Founders

Native Americans derive from a small number of Asian founders who likely arrived to the Americas via Beringia. However, additional details about the intial colonization of the Americas remain unclear. To investigate the pioneering phase in the Americas we analyzed a total of 623 complete mtDNAs from the Americas and Asia, including 20 new complete mtDNAs from the Americas and seven from Asia. This sequence data was used to direct high-resolution genotyping from 20 American and 26 Asian populations. Here we describe more genetic diversity within the founder population than was previously reported. The newly resolved phylogenetic structure suggests that ancestors of Native Americans paused when they reached Beringia, during which time New World founder lineages differentiated from their Asian sister-clades. This pause in movement was followed by a swift migration southward that distributed the founder types all the way to South America. The data also suggest more recent bi-directional gene flow between Siberia and the North American Arctic.