Beringia

Beringia is defined today as the land and maritime area bounded on the west by the Lena River in Russia; on the east by the Mackenzie River in Canada; on the north by 72 degrees north latitude in the Chukchi Sea; and on the south by the tip of the Kamchatka Peninsula.[1] It includes the Chukchi Sea, the Bering Sea, the Bering Strait, the Chukchi and Kamchatka Peninsulas in Russia as well as Alaska in the United States.

The area includes land lying on the North American Plate and Siberian land east of the Chersky Range. Historically, it formed a land bridge that was up to 1,000 kilometres (620 miles) wide at its greatest extent and which covered an area as large as British Columbia and Alberta together,[2] totaling approximately 1,600,000 square kilometres (620,000 square miles). Today, the only land that is visible from the central part of the Bering land bridge are the Diomede Islands, the Pribilof Islands of St. Paul and St. George, St. Lawrence Island, and King Island.[1]

The term Beringia was coined by the Swedish botanist Eric Hultén in 1937.[3] During the ice ages, Beringia, like most of Siberia and all of North and Northeast China, was not glaciated because snowfall was very light.[4] It was a grassland steppe, including the land bridge, that stretched for hundreds of kilometres into the continents on either side.

It is believed that a small human population of at most a few thousand arrived in Beringia from eastern Siberia during the Last Glacial Maximum before expanding into the settlement of the Americas sometime after 16,500 years BP.[5] This would have occurred as the American glaciers blocking the way southward melted,[6][7][8][9][10] but before the bridge was covered by the sea about 11,000 years BP.[11][12]

Before European colonization, Beringia was inhabited by the Yupik peoples on both sides of the straits. This culture remains in the region today along with others. In 2012, the governments of Russia and the United States announced a plan to formally establish "a transboundary area of shared Beringian heritage". Among other things this agreement would establish close ties between the Bering Land Bridge National Preserve and the Cape Krusenstern National Monument in the United States and Beringia National Park in Russia.[13]

Beringia land bridge-noaagov
Beringia sea levels measured in meters from 21,000 years ago to present
BeringiaMap-NPSgov
Beringia coverage

Geography

Beringia - late wisconsin glaciation
Bering land bridge – Wisconsin glaciation
Berengia - deglaciation period
Bering land bridge region – deglaciation period
Berengia - present day
Bering land bridge region – present day

The remains of Late Pleistocene mammals that had been discovered on the Aleutians and islands in the Bering Sea at the close of the nineteenth century indicated that a past land connection might lie beneath the shallow waters between Alaska and Chukotka. The underlying mechanism was first thought to be tectonics, but by 1930 changes in the icemass balance, leading to global sea-level fluctuations, were viewed as the cause of the Bering Land Bridge.[14][15] In 1937, Eric Hultén proposed that around the Aleutians and the Bering Strait region were tundra plants that had originally dispersed from a now-submerged plain between Alaska and Chukotka, which he named Beringia after Vitus Bering who had sailed into the strait in 1728.[16][15] The American arctic geologist David Hopkins redefined Beringia to include portions of Alaska and Northeast Asia. Beringia was later regarded as extending from the Verkhoyansk Mountains in the west to the Mackenzie River in the east.[15] The distribution of plants in the genera Erythranthe and Pinus are good examples of this, as very similar genera members are found in Asia and the Americas.[17][18]

During the Pleistocene epoch, global cooling led periodically to the expansion of glaciers and lowering of sea levels. This created land connections in various regions around the globe.[19] Today, the average water depth of the Bering Strait is 40–50 m (130–160 ft), therefore the land bridge opened when the sea level dropped more than 50 m (160 ft) below the current level.[20][21] A reconstruction of the sea-level history of the region indicated that a seaway existed from c. 135,000 – c. 70,000 BP, a land bridge from c. 70,000 – c. 60,000 BP, intermittent connection from c. 60,000 – c. 30,000 BP, a land bridge from c. 30,000 – c. 11,000 BP, followed by a Holocene sea-level rise that reopened the strait.[22][23] Post-glacial rebound has continued to raise some sections of coast.

During the last glacial period, enough of the earth's water became frozen in the great ice sheets covering North America and Europe to cause a drop in sea levels. For thousands of years the sea floors of many interglacial shallow seas were exposed, including those of the Bering Strait, the Chukchi Sea to the north, and the Bering Sea to the south. Other land bridges around the world have emerged and disappeared in the same way. Around 14,000 years ago, mainland Australia was linked to both New Guinea and Tasmania, the British Isles became an extension of continental Europe via the dry beds of the English Channel and North Sea, and the dry bed of the South China Sea linked Sumatra, Java, and Borneo to Indochina.

Beringian refugium

Lgm ccsm4 beringia annual precipitation
Beringia precipitation 22,000 years ago

The last glacial period, commonly referred to as the "Ice Age", spanned 125,000[24]–14,500 YBP[25] and was the most recent glacial period within the current ice age, which occurred during the last years of the Pleistocene era.[24] The Ice Age reached its peak during the Last Glacial Maximum, when ice sheets began advancing from 33,000 YBP and reached their maximum limits 26,500 YBP. Deglaciation commenced in the Northern Hemisphere approximately 19,000 YBP and in Antarctica approximately 14,500 years YBP, which is consistent with evidence that glacial meltwater was the primary source for an abrupt rise in sea level 14,500 YBP[25] and the bridge was finally inundated around 11,000 YBP.[12] The fossil evidence from many continents points to the extinction of large animals, termed Pleistocene megafauna, near the end of the last glaciation.[26]

During the Ice Age a vast, cold and dry Mammoth steppe stretched from the arctic islands southwards to China, and from Spain eastwards across Eurasia and over the Bering land bridge into Alaska and the Yukon where it was blocked by the Wisconsin glaciation. The land bridge existed because sea-levels were lower because more of the planet's water than today was locked up in glaciers. Therefore, the flora and fauna of Beringia were more related to those of Eurasia rather than North America. Beringia received more moisture and intermittent maritime cloud cover from the north Pacific Ocean than the rest of the Mammoth steppe, including the dry environments on either side of it. This moisture supported a shrub-tundra habitat that provided an ecological refugium for plants and animals.[27][28] In East Beringia 35,000 YBP, the northern arctic areas experienced temperatures 1.5 C degrees warmer than today but the southern sub-Arctic regions were 2 C degrees cooler. During the LGM 22,000 YBP the average summer temperature was 3–5 C degrees cooler than today, with variations of 2.9 C degrees cooler on the Seward Peninsula to 7.5 C cooler in the Yukon.[29] In the driest and coldest periods of the Late Pleistocene, and possibly during the entire Pleistocene, moisture occurred along a north-south gradient with the south receiving the most cloud cover and moisture due to the air-flow from the North Pacific.[28]

In the Late Pleistocene, Beringia was a mosaic of biological communities.[30][27][31] Commencing from c. 57,000 BP (MIS 3), steppe–tundra vegetation dominated large parts of Beringia with a rich diversity of grasses and herbs.[30][27][32] There were patches of shrub tundra with isolated refugia of larch (Larix) and spruce (Picea) forests with birch (Betula) and alder (Alnus) trees.[30][31][32][33] It has been proposed that the largest and most diverse megafaunal community residing in Beringia at this time could only have been sustained in a highly diverse and productive environment.[34] Analysis at Chukotka on the Siberian edge of the land bridge indicated that from c. 57,000 – c. 15,000 BP (MIS 3 to MIS 2) the environment was wetter and colder than the steppe–tundra to the east and west, with warming in parts of Beringia from c. 15,000 BP.[35] These changes provided the most likely explanation for mammal migrations after c. 15,000 BP, as the warming provided increased forage for browsers and mixed feeders.[36] Beringia did not block the movement of most dry steppe-adapted large species such as saiga antelope, woolly mammoth, and caballid horses. However, from the west the woolly rhino went no further east than the Anadyr River, and from the east North American camels, the American kiang-like equids, the short-faced bear, bonnet-headed muskoxen, and American badger did not travel west. At the beginning of the Holocene, some mesic habitat-adapted species left the refugium and spread westward into what had become tundra-vegetated northern Asia and eastward into northern North America.[28]

The latest emergence of the land bridge was c. 70,000 years ago. However, from c. 24,000 – c. 13,000 BP the Laurentide ice sheet fused with the Cordilleran ice sheet, which blocked gene flow between Beringia (and Eurasia) and continental North America.[37][38][39] The Yukon corridor opened between the receding ice sheets c. 13,000 BP, and this once again allowed gene flow between Eurasia and continental North America until the land bridge was finally closed by rising sea levels c. 10,000 BP.[40] During the Holocene, many mesic-adapted species left the refugium and spread eastward and westward, while at the same time the forest-adapted species spread with the forests up from the south. The arid adapted species were reduced to minor habitats or became extinct.[28]

Beringia constantly transformed its ecosystem as the changing climate affected the environment, determining which plants and animals were able to survive. The land mass could be a barrier as well as a bridge: during colder periods, glaciers advanced and precipitation levels dropped. During warmer intervals, clouds, rain and snow altered soils and drainage patterns. Fossil remains show that spruce, birch and poplar once grew beyond their northernmost range today, indicating that there were periods when the climate was warmer and wetter. The environmental conditions were not homogenous in Beringia. Recent stable isotope studies of woolly mammoth bone collagen demonstrate that western Beringia (Siberia) was colder and drier than eastern Beringia (Alaska and Yukon), which was more ecologically diverse.[41] Mastodons, which depended on shrubs for food, were uncommon in the open dry tundra landscape characteristic of Beringia during the colder periods. In this tundra, mammoths flourished instead.

The extinct pine species Pinus matthewsii has been described from Pliocene sediments in the Yukon areas of the refugium.[42]

The paleo-environment changed across time.[43] Below is a gallery of some of the plants that inhabited eastern Beringia before the beginning of the Holocene.

Human habitation

Map of gene flow in and out of Beringia
Genetic settlement of Beringia

The Bering land bridge is a postulated route of human migration to the Americas from Asia about 20,000 years ago.[45] An open corridor through the ice-covered North American Arctic was too barren to support human migrations before around 12,600 BP.[46][47] A study has indicated that the genetic imprints of only 70 of all the individuals who settled and traveled the land bridge into North America are visible in modern descendants. This genetic bottleneck finding is an example of the founder effect and does not imply that only 70 individuals crossed into North America at the time; rather, the genetic material of these individuals became amplified in North America following isolation from other Asian populations.[48]

Seagoing coastal settlers may also have crossed much earlier, but there is no scientific consensus on this point, and the coastal sites that would offer further information now lie submerged in up to a hundred metres of water offshore. Land animals migrated through Beringia as well, introducing to North America species that had evolved in Asia, like mammals such as proboscideans and American lions, which evolved into now-extinct endemic North American species. Meanwhile, equids and camelids that had evolved in North America (and later became extinct there) migrated into Asia as well at this time.

A 2007 analysis of mtDNA found evidence that a human population lived in genetic isolation on the exposed Beringian landmass during the Last Glacial Maximum for approximately 5,000 years.[49] This population is often referred to as the Beringian Standstill population.[49][50] A number of other studies, relying on more extensive genomic data, have come to the same conclusion.[6][51][52] Genetic[49] and linguistic[53] data demonstrate that at the end of the Last Glacial Maximum, as sea levels rose, some members of the Beringian Standstill Population migrated back into eastern Asia while others migrated into the Western Hemisphere, where they became the ancestors of the indigenous people of the Western Hemisphere. Environmental selection on this Beringian Standstilll Population has been suggested for genetic variation in the Fatty Acid Desaturase gene cluster[54] and the ectodysplasin A receptor gene.[55] Using Y Chromosome data Pinotti et. al. have estimated the Beringian Standstill to be less than 4600 years and taking place between 19.5 kya and 15 kya.[56]

Previous connections

Biogeographical evidence demonstrates previous connections between North America and Asia. Similar dinosaur fossils occur both in Asia and in North America. For instance the dinosaur Saurolophus was found in both Mongolia and western North America. Relatives of Troodon, Triceratops, and even Tyrannosaurus rex all came from Asia.

Fossils in China demonstrate a diffusion of Asian mammals into North America around 55 million years ago. By 20 million years ago, evidence in North America shows a further interchange of mammalian species. Some, like the ancient saber-toothed cats, have a recurring geographical range: Europe, Africa, Asia, and North America. The only way they could reach the New World was by the Bering land bridge. Had this bridge not existed at that time, the fauna of the world would be very different.

See also

References

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Further reading

External links

Ancient Beringian

This is about the genetic lineage associated with the peopling of the Americas. For the archaeogenetics of the USR population, see Upward Sun River site#Archaeogenetics.

The Ancient Beringians (AB) is the name given to a specific archaeogenetic lineage, based on the genome of an infant found at the Upward Sun River site (dubbed USR1), dated to 11,500 years ago.

The AB lineage diverged from the Ancestral Native American (ANA) lineage

about 20,000 years ago. The ANA lineage was estimated as having been formed between 20,000 and 25,000 years ago by

a mixture of Proto-Mongoloid and Ancient North Eurasian lineages, consistent with the model of the peopling of the Americas via Beringia during the Last Glacial Maximum.

The Ancient Beringian lineage is extinct, and is not found as a contribution to modern indigenous lineages in Alaska.

The 2018 study suggests that the AB lineage was replaced by or absorbed in a back-migration of NNA to Alaska.

The modern Athabaskan populations are derived from an admixture of this NNA back-migration and a Paleo-Siberian (Early Paleo-Eskimo) lineage before about 2,500 years ago.The discovery was made from archaeogenetic analyses on the remains of two female infants discovered in 2013 at the Upward Sun River site (USR).

The USR site is affiliated with the Denali Complex, a dispersed archaeological culture of the American Arctic.

The genomic analysis of nuclear DNA of the older of the two infants (USR1) was done at the Centre for Geogenetics at the University of Copenhagen's Natural History Museum of Denmark. Results from the team's genetic analysis were published in January 2018 in the scientific journal Nature.

The analysis compared the infant's genomes with both ancient and contemporary genomes. The results suggested that the pre-"Ancestral Native American" lineage derived from the proto-Mongoloid lineage after 36 kya, with gene flow until about 25 kya.

During 25–20 kya, this lineage was substantially mixed with the Ancient North Eurasian lineage, to form the "Ancestral Native American" lineage by 20 kya.

The "Ancient Beringian" (AB) lineage derived from ANA and persisted without significant admixture in Alaska until the time of USR1, some 8,000 years later. The lineage of other Paleo-Indians diverged form AB at ca. 20–18 kya, and further divided into "North Native American" (NNA) and "South Native American" lineages between 17.5 kya and 14.6 kya, reflecting the dispersal associated with the early peopling of the Americas.

Anglo-Egyptian Darfur Expedition

The Anglo-Egyptian Darfur Expedition of 1916 was a military operation by British Empire and the Sultanate of Egypt, launched as a preemptive invasion of the Sultanate of Darfur.

The sultan of Darfur Ali Dinar had been reinstated by the British after their victory in the Mahdist War but during the First World War he grew restive, refusing his customary tribute to the Sudanese government and showing partiality to the Ottoman Empire in 1915.

Sirdar Reginald Wingate then organized a force of around 2,000 men; under the command of Lieutenant-Colonel Philip James Vandeleur Kelly, the force entered Darfur in March 1916 and decisively defeated the Fur Army at Beringia and occupied the capital El Fasher in May. Ali Dinar had already fled to the mountains and his attempts to negotiate a surrender were eventually broken off by the British. His location becoming known, a small force was sent after him and the sultan was killed in action in November 1916. Subsequently, Darfur was fully annexed to the British administration of the Anglo-Egyptian Sudan and remained part of Sudan upon its independence.

Anzick-1

Anzick-1 is the name given to the remains of Paleo-Indian male infant found in south central Montana, U.S. in 1968 that date to 12,707–12,556 years BP. The child was found with more than 115 tools made of stone and antlers and dusted with red ocher, suggesting an honorary burial. Anzick-1 is the only human who has been discovered from the Clovis Complex, and is the first ancient Native American genome to be fully sequenced.Paleogenomic analysis of the remains revealed Siberian ancestry and a close genetic relationship to modern Native Americans, including those of Central and South America. These findings support the hypothesis that modern Native Americans are descended from Asian populations who crossed Beringia between 32,000 and 18,000 years ago.Anzick-1's discovery and subsequent analysis has been controversial. The remains were found on private land, so the researchers did not violate the Native American Graves Protection and Repatriation Act (NAGPRA) in their study. But many Native American tribal members in Montana believed they should have been consulted before the researchers undertook analysis of the infant's skeleton and genome.Anzick-1 was reburied on June 28, 2014 in the Shields River Valley in an intertribal ceremony. The numerous Clovis artifacts associated with the first burial are archived at the Montana Historical Society in Helena, Montana.

Arabidopsis

Arabidopsis (rockcress) is a genus in the family Brassicaceae. They are small flowering plants related to cabbage and mustard. This genus is of great interest since it contains thale cress (Arabidopsis thaliana), one of the model organisms used for studying plant biology and the first plant to have its entire genome sequenced. Changes in thale cress are easily observed, making it a very useful model.

Beringia National Park

Beringia National Park (Russian: Берингия) is on the eastern tip of Chukotka Autonomous Okrug ("Chukotka"), the most northeastern region of Russia. It is on the western (i.e., Asian) side of the Bering Strait.

Beringia lowland tundra

The Beringia lowland tundra is a tundra ecoregion of North America, on the west coast of Alaska, mostly covered in wetland.

Beringia upland tundra

The Beringia upland tundra is a mountainous tundra ecoregion of North America, on the west coast of Alaska.

Beringian wolf

The Beringian wolf is an extinct type of wolf (Canis lupus) that lived during the Ice Age. It inhabited what is now modern-day Alaska, Yukon, and northern Wyoming. Some of these wolves survived well into the Holocene. The Beringian wolf is an ecomorph of the gray wolf and has been comprehensively studied using a range of scientific techniques, yielding new information on the prey species and feeding behavior of prehistoric wolves. It has been determined that these wolves are morphologically distinct from modern North American wolves and genetically basal to most modern and extinct wolves. The Beringian wolf has not been assigned a subspecies classification and its relationship with the extinct European cave wolf (Canis lupus spelaeus) is not clear.

The Beringian wolf was similar in size to the modern Yukon wolf (Canis lupus pambasileus) and other Late Pleistocene gray wolves but more robust and with stronger jaws and teeth, a broader palate, and larger carnassial teeth relative to its skull size. In comparison with the Beringian wolf, the more southerly occurring dire wolf (Canis dirus) was the same size but heavier and with a more robust skull and dentition. The unique adaptation of the skull and dentition of the Beringian wolf allowed it to produce relatively large bite forces, grapple with large struggling prey, and therefore made predation and scavenging on Pleistocene megafauna possible. The Beringian wolf preyed most often on horse and steppe bison, and also on caribou, mammoth, and woodland muskox.

At the close of the Ice Age, with the loss of cold and dry conditions and the extinction of much of its prey, the Beringian wolf became extinct. The extinction of its prey has been attributed to the impact of climate change, competition with other species, including humans, or a combination of both factors. Local genetic populations were replaced by others from within the same species or of the same genus. Of the North American wolves, only the ancestor of the modern North American gray wolf survived. The remains of ancient wolves with similar skulls and dentition have been found in western Beringia (north-east Siberia). In 2016 a study showed that some of the wolves now living in remote corners of China and Mongolia share a common maternal ancestor with one 28,000-year-old eastern Beringian wolf specimen.

Dené–Yeniseian languages

Dené–Yeniseian is a proposed language family consisting of the Yeniseian languages of central Siberia and the Na-Dené languages of northwestern North America.

Reception among experts has been largely, though not universally, favorable; thus, Dené–Yeniseian has been called "the first demonstration of a genealogical link between Old World and New World language families that meets the standards of traditional comparative-historical linguistics".

Genetic history of indigenous peoples of the Americas

The genetic history of Indigenous peoples of the Americas (also named Amerindians or Amerinds in physical anthropology) is divided into two sharply distinct episodes:

the initial peopling of the Americas during about 20,000 to 14,000 years ago (20–14 kya), and European contact, after about 500 years ago. The former is the determinant factor for the number of genetic lineages, zygosity mutations and founding haplotypes present in today's Indigenous Amerindian populations.Most Amerindians groups are derived from a basal Ancestral lineage, which formed in Siberia prior to the Last Glacial Maximum, between about 36,000 and 25,000 years ago, from a combination of Proto-Mongoloid and Ancient North Eurasian ancestry and which dispersed throughout the Americas after about 16,000 years ago (an exception are the Na Dene and Eskimo–Aleut speaking groups, which are partially derived from Siberian populations which entered the Americas at a later time).In the early 2000s, archaeogenetics was primarily based on Human Y-chromosome DNA haplogroups and Human mitochondrial DNA haplogroups. Autosomal "atDNA" markers are also used, but differ from mtDNA or Y-DNA in that they overlap significantly.Analyses of genetics among Amerindian and Siberian populations have been used to argue for early isolation of founding populations on Beringia and for later, more rapid migration from Siberia through Beringia into the New World. The microsatellite diversity and distributions of the Y lineage specific to South America indicates that certain Amerindian populations have been isolated since the initial colonization of the region. The Na-Dené, Inuit and Indigenous Alaskan populations exhibit Haplogroup Q-M242; however, they are distinct from other indigenous Amerindians with various mtDNA and atDNA mutations. This suggests that the peoples who first settled in the northern extremes of North America and Greenland derived from later migrant populations than those who penetrated farther south in the Americas. Linguists and biologists have reached a similar conclusion based on analysis of Amerindian language groups and ABO blood group system distributions.

Megafaunal wolf

The megafaunal wolf (Canis cf. lupus) was a Late Pleistocene – early Holocene hypercarnivore similar in size to a large extant gray wolf. It had a shorter, broader palate with large carnassial teeth relative to its overall skull size. This adaptation allowed it to prey and scavenge on Pleistocene megafauna. Such an adaption is an example of phenotypic plasticity.

Paleo-Arctic Tradition

The Paleo-Arctic Tradition is the name given by archaeologists to the cultural tradition of the earliest well-documented human occupants of the North American Arctic, which date from the period 8000–5000 BC. The tradition covers Alaska and expands far into the east, west, and the Southwest Yukon Territory.

The Upward Sun River site, a Late Pleistocene archaeological site associated with the Paleo-Arctic Tradition, located in the Tanana Valley, Alaska has now been dated to around 11,500 BP. Upward Sun River is the site of the oldest human remains discovered on the American side of Beringia.Around 8000 BC, Alaska was still connected to Siberia with the landbridge, located in the current Bering Strait. People who inhabited this region in Alaska were of the Dyuktai tradition, originally located in Siberia. Eventually, the Dyuktai changed into the Sumnagin culture, a hunting/fishing group, whose culture was defined by possessing a new technology. Other cultures flourished as well, all being placed under the general category of the Paleo-Arctic tradition.

"The Paleo-Arctic tradition is still a shadowy entity, a patchwork of local Early Holocene cultural traditions that flourished over an enormous area of extreme northwestern North America for at least 4000 years, and longer in many places. Other terms such as the Northwest Microblade tradition, Denali Complex, and Beringian tradition have been used to describe these same general adaptations, but Paleo-Arctic is the most appropriate because it is the kind of general label that reflects a great variety of different human adaptations during a period of increasing environmental diversity and change" (Fagan, p.173).The Paleo-Arctic is mostly known for lithic remains (stone technology). Some artifacts found include microblades, small wedge-shaped cores, some leaf-shaped bifaces, scrapers, and graving tools. The microblades were used as hunting weapons and were mounted in wood, antler, or bone points. Paleo-Arctic stone specialists also created bifaces that were used as tools and as cores for the production of large artifact blanks. Little evidence remains of the culture's settlement patterns, because many of the settlements were inundated by the rising sea levels of the Holocene; however, remains of stone tools were discovered, giving indirect evidence of settlement sites.

Paleo-Indians

Paleo-Indians, Paleoindians or Paleoamericans is a classification term given by scholars to the first peoples who entered, and subsequently inhabited, the Americas during the final glacial episodes of the late Pleistocene period. The prefix "paleo-" comes from the Greek adjective palaios (παλαιός), meaning "old" or "ancient". The term "Paleo-Indians" applies specifically to the lithic period in the Western Hemisphere and is distinct from the term "Paleolithic".Traditional theories suggest that big-animal hunters crossed the Bering Strait from North Asia into the Americas over a land-and-ice bridge (Beringia). This bridge existed from 45,000–12,000 BCE (47,000–14,000 BP). Small isolated groups of hunter-gatherers migrated alongside herds of large herbivores far into Alaska. From c. 16,500 – c. 13,500 BCE (c. 18,500 – c. 15,500 BP), ice-free corridors developed along the Pacific coast and valleys of North America. This allowed animals, followed by humans, to migrate south into the interior of the continent. The people went on foot or used primitive boats along the coastline. The precise dates and routes of the peopling of the New World remain subjects of ongoing debate.Stone tools, particularly projectile points and scrapers, are the primary evidence of the earliest human activity in the Americas. Archaeologists and anthropologists use surviving crafted lithic flaked tools to classify cultural periods. Scientific evidence links Indigenous Americans to eastern Siberian populations. Indigenous peoples of the Americas have been linked to Siberian populations by linguistic factors, the distribution of blood types, and in genetic composition as reflected by molecular data, such as DNA. There is evidence for at least two separate migrations.

From 8000–7000 BCE (10,000–9,000 BP) the climate stabilized, leading to a rise in population and lithic technology advances, resulting in more sedentary lifestyle.

Phiomorpha

The rodent parvorder or infraorder Phiomorpha comprises several living and extinct families found wholly or largely in Africa. Along with the Anomaluromorpha and perhaps the †Zegdoumyidae, they represent one of the few early colonizations of Africa by rodents.

During the Oligocene, Africa was not connected to any of the other continents. The predominant theory suggests that rodents first evolved in Laurasia, and expanded outward from there. Although Europe, Asia, and North America were distinct landmasses during much of the Eocene and Oligocene, they experienced intermittent migration events across the shallow sea separating Europe and Asia, via an ice-free Greenland (Europe and North America), or across Beringia (North America and Asia). The southern continents were much more isolated leading to the unique faunas of Australia, South America, and to a lesser degree Africa.

Although the hystricognath rodents may have evolved from an early entodacryan ancestor in Asia, they migrated to Africa soon after. The Phiomorpha represents the clade that evolved as a result. Although once diverse, this infraorder is now restricted to the two species of cane rats, the dassie rat, and the blesmols.

Settlement of the Americas

The first settlement of the Americas began when Paleolithic hunter-gatherers first entered North America from the North Asian Mammoth steppe via the Beringia land bridge, which had formed between northeastern Siberia and western Alaska due to the lowering of sea level during the Last Glacial Maximum.

These populations expanded south of the Laurentide Ice Sheet and rapidly throughout both North and South America, by 14,000 years ago. The earliest populations in the Americas, before roughly 10,000 years ago, are known as Paleo-Indians.

The peopling of the Americas is a long-standing open question, and while advances in archaeology, Pleistocene geology, physical anthropology, and DNA analysis have shed progressively more light on the subject, significant questions remain unresolved. While there is general agreement that the Americas were first settled from Asia, the pattern of migration, its timing, and the place(s) of origin in Eurasia of the peoples who migrated to the Americas remain unclear.The prevalent migration models outline different time frames for the Asian migration from the Bering Straits and subsequent dispersal of the founding population throughout the continent. Indigenous peoples of the Americas have been linked to Siberian populations by linguistic factors, the distribution of blood types, and in genetic composition as reflected by molecular data, such as DNA.The "Clovis first theory" refers to the 1950s hypothesis that the Clovis culture represents the earliest human presence in the Americas, beginning about 13,000 years ago; evidence of pre-Clovis cultures has accumulated since 2000, pushing back the possible date of the first peopling of the Americas to about 13,200–15,500 years ago.

Steppe bison

The steppe bison or steppe wisent (Bison priscus) is an extinct species of bison that was once found on the mammoth steppe where its range included Europe, Central Asia, Northern to Northeastern Asia, Beringia, and North America, from northwest Canada to Mexico during the Quaternary. Three chronological subspecies, Bison priscus priscus, Bison priscus mediator, and Bison priscus gigas, have been suggested.

Upward Sun River site

The Upward Sun River site, or Xaasaa Na’, is a Late Pleistocene archaeological site associated with the Paleo-Arctic Tradition, located in the Tanana River Valley, Alaska. Dated to around 11,500 BP, Upward Sun River is the site of the oldest human remains discovered on the American side of Beringia. The site was first discovered in 2006.

The layer with the human remains at Upward Sun River is most similar to the level 6 layer from Ushki Lake, Kamchatka. Both sites are the only Beringian burials found so far from that period.

Yugyd Va National Park

Yugyd Va National Park (Komi, Russian: Югыд ва) is a national park in the Komi Republic, a constituent republic of the Russian Federation. It is Europes largest national park (ahead of Vatnajökull National Park in Iceland) and it was Russia's largest national park until the creation of Beringia National Park in 2013.

Yukon Beringia Interpretive Centre

The Yukon Beringia Interpretive Centre is a research and exhibition facility located at km 1423 (Mile 886) on the Alaska Highway in Whitehorse, Yukon, which opened in 1997. The focus of the interpretive centre is the story of Beringia, the 3200 km landmass stretching from the Kolyma River in Siberia to the MacKenzie River in Canada, which remained non-glaciated during the Pleistocene due to light snowfall from an arid climate. Beringia is of special interest to archeologists and paleontologists as it played a crucial role in the migrations of many animals and humans between Asia and the Americas. The term Beringia was first coined by the Swedish botanist Eric Hultén in 1937.

During Beringia's long history some animals migrated Easterly (mastodons, gomphotheres, mammoths, various members of the deer family, bison, sheep and muskoxen) others Westerly (equines, camels), and yet others reveal many episodes of dispersal (such as lemmings and voles).

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