Models of migration to the New World

There have been several models for the human settlement of the Americas proposed by various academic communities. The question of how, when and why humans (Paleo-Indians) first entered the Americas

Americas

The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

is of intense interest to archaeologists and anthropologists, and has been a subject of heated debate for centuries. Modern biochemical techniques, as well as more thorough archaeology, have shed progressively more light on the subject.

Current understanding of human migration to and throughout the Americas derives from advances in four interrelated disciplines: archeology, physical anthropology

Physical anthropology

Biological anthropology is that branch of anthropology that studies the physical development of the human species. It plays an important part in paleoanthropology and in forensic anthropology...

, DNA analysis and linguistics

Linguistics

Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....

. While there is general agreement that America was first settled from Asia by people who migrated across Beringia, the pattern of migration, its timing, and the place of origin in Asia of the peoples who migrated to the Americas remains unclear.

In recent years researchers have sought to use familiar tools to validate or reject established theories such as Clovis first

Clovis culture

The Clovis culture is a prehistoric Paleo-Indian culture that first appears 11,500 RCYBP , at the end of the last glacial period, characterized by the manufacture of "Clovis points" and distinctive bone and ivory tools...

. As new discoveries come to light, past hypotheses are reevaluated and new theories constructed. The archeological evidence suggests that the Paleo-Indians' first "widespread" habitation of the Americas occurred during the end of the last glacial period or, more specifically, what is known as the late glacial maximum, around 16,500–13,000 years ago.

Understanding the debate

The chronology of migration models is currently divided into two general approaches. The first is the short chronology theory with the first movement beyond Alaska into the New World occurring no earlier than 15,000 – 17,000 years ago, followed by successive waves of immigrants. The second belief is the long chronology theory, which proposes that the first group of people entered the hemisphere at a much earlier date, possibly 21,000–40,000 years ago, with a much later mass secondary wave of immigrants.

One factor fueling the debate is the discontinuity of archaeological

Archaeology

Archaeology, or archeology , is the study of human society, primarily through the recovery and analysis of the material culture and environmental data that they have left behind, which includes artifacts, architecture, biofacts and cultural landscapes...

evidence between North and South America Paleo-Indian sites. A roughly uniform techno-complex pattern known as Clovis

Clovis culture

appears in North and Central America

Central America

Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

n sites from at least 13,500 years ago onwards. South American sites of equal antiquity do not share the same consistency and exhibit more diverse cultural patterns. Archaeologists conclude that the "Clovis-first", and Paleo-Indian time frame do not adequately explain complex lithic stage

Lithic stage

In the sequence of North American prehistoric cultural stages first proposed by Gordon Willey and Philip Phillips in 1958, the Lithic stage was the earliest period of human occupation in the Americas, accruing during the Late Pleistocene period, to time before 8,000 B.C....

tools appearing in South America. Some theorists seek to develop a colonization model that integrates both North and South American archaeological records.

**Availability of unobstructed routes for human migration southward from Beringia during the ice age (summarized)**
Dates BCE	Beringia "Land Bridge"	Coastal Route	Mackenzie Corridor
38,000-34,000	style="text-align:center;"!	style="text-align:center;"!	style="text-align:center;"!
34,000-30,000	style="text-align:center;"!	style="text-align:center;"!	style="text-align:center;"!
30,000-22,000	style="text-align:center;"!	style="text-align:center;"!	style="text-align:center;"!
22,000-15,000	style="text-align:center;"!	style="text-align:center;"!	style="text-align:center;"!
15,000 - today	style="text-align:center;"!	style="text-align:center;"!	style="text-align:center;"!

Indigenous Amerindian genetic studies indicate that the "colonizing founders" of the Americas emerged from a single-source ancestral population that evolved in isolation, likely in Beringia. Age estimates based on Y-chromosome micro-satellite place diversity of the American Haplogroup Q1a3a (Y-DNA) at around 10,000 to 15,000 years ago. This does not address if there were any previous failed colonization attempts by other genetic groups, as genetic testing can only address current population ancestral heritage.

Migrants from northeastern Asia could have walked to Alaska with relative ease when Beringia was above sea level. But traveling south from Alaska to the rest of North America may have posed significant challenges. The two main possible routes proposed south for human migration are: down the Pacific coast

Pacific Coast

A country's Pacific coast is the part of its coast bordering the Pacific Ocean.-The Americas:Countries on the western side of the Americas have a Pacific coast as their western border.* Geography of Canada* Geography of Chile* Geography of Colombia...

or by way of an interior passage (Mackenzie Corridor) along the eastern flank of the Rocky Mountains

Rocky Mountains

The Rocky Mountains are a major mountain range in western North America. The Rocky Mountains stretch more than from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States...

. When the Laurentide

Laurentide ice sheet

The Laurentide Ice Sheet was a massive sheet of ice that covered hundreds of thousands of square miles, including most of Canada and a large portion of the northern United States, multiple times during Quaternary glacial epochs. It last covered most of northern North America between c. 95,000 and...

and Cordilleran ice sheet

Cordilleran Ice Sheet

The Cordilleran ice sheet was a major ice sheet that covered, during glacial periods of the Quaternary, a large area of North America. This included the following areas:*Western Montana*The Idaho Panhandle...

s were at their maximum extent, both routes were likely impassable. The Cordilleran sheet reached across to the Pacific shore in the west, and its eastern edge abutted the Laurentide, near the present border between British Columbia and Alberta.
Geological evidence suggests the Pacific coastal route was open for overland travel before 23,000 years ago and after 15,000 years ago. During the coldest millennia of the last ice age, roughly 23,000 to 19,000 years ago, lobes of glacier

Glacier

A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...

s hundreds of kilometers wide flowed down to the sea. Deep crevasses scarred their surfaces, making travel across them dangerous. Even if people traveled by boat—a claim for which there is currently no direct archaeological evidence as sea level rise has hidden the old coastline — the journey would have been difficult with abundant icebergs in the water. Around 15,000 to 13,000 years ago, the coast was presumed ice-free. Additionally, by this time the climate had warmed, and lands were covered in grass and trees. Early Paleo-Indian groups could have readily replenished their food supplies, repaired clothing and tents, and replaced broken or lost tools.

Coastal or "watercraft" theories have broad implications: one being that Paleo-Indians in North America may not have been purely terrestrial big-game hunters, but instead were already adapted to maritime or semi-maritime lifestyles. Additionally, it is possible that "Beringian" (western Alaskan) groups migrated into the northern interior and coastlines only to meet their demise during the last glacial maximum

Last Glacial Maximum

The Last Glacial Maximum refers to a period in the Earth's climate history when ice sheets were at their maximum extension, between 26,500 and 19,000–20,000 years ago, marking the peak of the last glacial period. During this time, vast ice sheets covered much of North America, northern Europe and...

, approximately 20,000 years ago, leaving evidence of occupation in specific localized areas. However, they would not be considered a founding population

Founder effect

In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. It was first fully outlined by Ernst Mayr in 1942, using existing theoretical work by those such as Sewall...

unless they had managed to migrate south, populate and survive the coldest part of the last ice age.

Timeline of selected archaeological, geological and genetic evidence

40,000 B.C. – 25,000 B.C. Paleolithic Paleolithic The Paleolithic Age, Era or Period, is a prehistoric period of human history distinguished by the development of the most primitive stone tools discovered , and covers roughly 99% of human technological prehistory... people move into Beringia across the Bering Land Bridge into western Alaska Alaska Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait... . Bison Bison Members of the genus Bison are large, even-toed ungulates within the subfamily Bovinae. Two extant and four extinct species are recognized... (buffalo), mammoth Mammoth A mammoth is any species of the extinct genus Mammuthus. These proboscideans are members of Elephantidae, the family of elephants and mammoths, and close relatives of modern elephants. They were often equipped with long curved tusks and, in northern species, a covering of long hair... s, and mastodon Mastodon Mastodons were large tusked mammal species of the extinct genus Mammut which inhabited Asia, Africa, Europe, North America and Central America from the Oligocene through Pleistocene, 33.9 mya to 11,000 years ago. The American mastodon is the most recent and best known species of the group... s are thought to have migrated from Asia to America about this time. This would imply a land bridge between the continents that would have had a food supply.
30,000–20,000 years ago: Mammoth Mammoth A mammoth is any species of the extinct genus Mammuthus. These proboscideans are members of Elephantidae, the family of elephants and mammoths, and close relatives of modern elephants. They were often equipped with long curved tusks and, in northern species, a covering of long hair... bones, believed to have been chipped by humans, are found at the Yukon Yukon Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in.... 's Bluefish Caves Bluefish Caves Bluefish Caves is an archaeological site in the Yukon Territory of Canada from which a specimen of allegedly human-worked mammoth bone has been radiocarbon dated to 28,000 years before present .... sites investigated in the 1970s and 1980s by archeologist Jacques Cinq-Mars and his team. In 2004, Albert Goodyear Albert Goodyear Albert C. Goodyear III is an archaeologist who is founder and director of the Allendale PaleoIndian Expedition in South Carolina, where he has unearthed controversial evidence that may greatly move back the date of occupation of North America by humans to 50,000 years or more before the present... of the South Carolina Institute of Archaeology and Anthropology South Carolina Institute of Archaeology and Anthropology The South Carolina Institute of Archaeology and Anthropology, or SCIAA, was founded in 1963 as a research institute at University of South Carolina and as a State cultural resource management agency... announced radiocarbon dating of a bit of charcoal found in the Topper Site Topper (archaeological site) Topper is an archaeological site located along the Savannah River in Allendale County, South Carolina in the United States. It is noted as the location of controversial artifacts believed by some archaeologists to indicate human habitation of the New World earlier than the Clovis culture,... that preceded Clovis culture, near Allendale County, South Carolina Allendale County, South Carolina -Demographics:As of the census of 2000, there were 11,211 people, 3,915 households and 2,615 families residing in the county. The population density was 28 people per square mile . There were 4,568 housing units at an average density of 11 per square mile... . However, these deposits may have been made by forest fires. (Note: The dates given for the Old Crow and Topper digs have not been completely accepted by the archaeology community.) Ice-free corridor running north and south through Alberta Alberta Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces... and the continental glacier Continental Glacier Continental Glacier is located in Bridger-Teton and Shoshone National Forests, in the U.S. state of Wyoming and straddles the Continental Divide in the northern Wind River Range. Continental Glacier is in both the Bridger and Fitzpatrick Wildernesses, and is part of the largest grouping of glaciers... called Laurentide ice sheet Laurentide ice sheet The Laurentide Ice Sheet was a massive sheet of ice that covered hundreds of thousands of square miles, including most of Canada and a large portion of the northern United States, multiple times during Quaternary glacial epochs. It last covered most of northern North America between c. 95,000 and... . Introduced by geologists in the 1950s when stone tools were found in the Grimshaw, Bow River Bow River The Bow River is a river in the Canadian province of Alberta. It is a tributary of the South Saskatchewan River, and is considered the headwater of the Nelson River.... and in Lethbridge Lethbridge Lethbridge is a city in the province of Alberta, Canada, and the largest city in southern Alberta. It is Alberta's fourth-largest city by population after Calgary, Edmonton and Red Deer, and the third-largest by area after Calgary and Edmonton. The nearby Canadian Rockies contribute to the city's... Alberta, under glacial sand and gravel; they are believed to be pre-glacial and may indicate nomadic humans occupied the area. A child's skull found in 1961 near Taber, Alberta is believed to be of one of the oldest inhabitants discovered in Alberta. (Note: The conclusions reached in Alberta on dates have not been accepted by the entire archaeology community.) Cambridge DNA Services estimates humans entered the Americas around 25,000 years ago. Other geneticists have variously estimated that peoples of Asia and the Americas were part of the same population from about 21,000 to 42,000 years ago. Siberian mammoth Mammoth A mammoth is any species of the extinct genus Mammuthus. These proboscideans are members of Elephantidae, the family of elephants and mammoths, and close relatives of modern elephants. They were often equipped with long curved tusks and, in northern species, a covering of long hair... hunters were believed to have penetrated far into the Arctic Arctic The Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost... where ice-free corridors north during the time are believed found. Theory first introduced by geologists in the late 1970s when core samples indicate the ice is no older than 17,000 years old.
23,000–16,500 years ago: The Ice Age Ice age An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers... entombs the northern hemisphere Northern Hemisphere The Northern Hemisphere is the half of a planet that is north of its equator—the word hemisphere literally means “half sphere”. It is also that half of the celestial sphere north of the celestial equator... in glaciers, cutting off routes from Siberia to the south. 2002 the presence of the X haplogroup Haplogroup X (mtDNA) In human mitochondrial genetics, Haplogroup X is a human mitochondrial DNA haplogroup. It has a widespread global distribution but no major regions of distinct localization.-Origin:... was found in a small percentage of modern indigenous Americans that is known to exist in a few locations in Europe and the Middle East. Subsequent research indicated that this DNA was not the result of genetic mixing after Columbus. However, the time estimates on haplogroup X entering Americas is around 15,000 to 20,000 years ago. Genetic evidence (2007–2009) suggests the Beringia population's first genetic diversification from Asian populations occurred. An article in the American Journal of Human Genetics American Journal of Human Genetics The American Journal of Human Genetics is a medical journal in the field of human genetics. Since its inception in 1948 by the American Society of Human Genetics, the journal has provided a record of research and review relating to heredity in humans and to the application of genetic principles in... states "Here we show, by using 86 complete mitochondrial genomes, that all Native American haplogroups, including haplogroup X, were part of a single founding population.
16,500–13,000 years ago: Receding glaciers reopened an ice-free corridor through Canada between Alaska and the rest of the Americas. Massive flooding would have created large lakes covering vast areas of north America with glacial waters. Age estimates based on Y-chromosome micro-satellite place diversity of the so called "American Haplo" Q1a3a1 at around 10,000 to 15,000 years ago. Mass extinction of large fauna begins due to climate change and perhaps hunting. The Dire Wolf Dire Wolf The Dire Wolf, Canis dirus, is an extinct carnivorous mammal of the genus Canis, and was most common in North America and South America from the Irvingtonian stage to the Rancholabrean stage of the Pleistocene epoch living 1.80 Ma – 10,000 years ago, existing for approximately .- Relationships... , Smilodon Smilodon Smilodon , often called a saber-toothed cat or saber-toothed tiger, is an extinct genus of machairodonts. This saber-toothed cat was endemic to North America and South America, living from near the beginning through the very end of the Pleistocene epoch .-Etymology:The nickname "saber-tooth" refers... , Cave Lion, Giant beaver Giant Beaver Castoroides ohioensis was a species of giant beaver, huge members of the family Castoridae , endemic to North America during the Pleistocene epoch .-Morphology:... , Ground sloth Ground sloth Ground sloths are a diverse group of extinct sloths, in the mammalian superorder Xenarthra. Their most recent survivors lived in the Antilles, where it has been proposed they may have survived until 1550 CE; however, the youngest AMS radiocarbon date reported is 4190 BP, calibrated to c. 4700 BP... , Mammoth, American Mastodon American mastodon The American mastodon is an extinct North American proboscidean that lived from about 3.7 million years ago until about 10,000 BC. It was the last surviving member of the mastodon family. Fossil finds range from present-day Alaska and New England in the north, to Florida, southern... , American Camel Camelops Camelops is an extinct genus of camels that once roamed western North America, where it disappeared at the end of the Pleistocene about 10,000 years ago. Its name is derived from the Greek κάμελος + , thus "camel-face."-Background:... , American Equine Equus (genus) Equus is a genus of animals in the family Equidae that includes horses, donkeys, and zebras. Within Equidae, Equus is the only extant genus. Like Equidae more broadly, Equus has numerous extinct species known only from fossils. This article deals primarily with the extant species.The term equine... , and American lion American lion The American lion — also known as the North American lion, Naegele’s giant jaguar or American cave lion — is an extinct lion of the family Felidae, endemic to North America during the Pleistocene epoch , existing for approximately... all become extinct by 11,000 years ago. Pre-Clovis sites uncovered from 1973 to 1978 Meadowcroft Rockshelter in Pennsylvania Pennsylvania The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to... site indicated occupancy as early as 16,000 years ago and possibly as long as 19,000 years ago. Dates in excess of 19,000 years have been claimed for the deepest occupation layer uncovered. pre-Clovis sites found in Monte Verde Monte Verde Monte Verde is an archaeological site in southern Chile, located in the northern Patagonia near Puerto Montt, Chile, which has been dated to 14,800 years BP . This dating adds to the evidence showing that settlement in the Americas pre-dates the Clovis culture by roughly 1000 years... , located along Chinchihuapi Creek, in Chile Chile Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far... . A crew of eighty people, led by Tom Dillehay Tom Dillehay Tom Dillehay is an American anthropologist who is the Rebecca Webb Wilson University Distinguished Professor of Anthropology, Religion, and Culture and Professor of Anthropology at Vanderbilt University. While working at Universidad Austral de Chile he was involved in the excavations at Monte Verde... of the University of Kentucky University of Kentucky The University of Kentucky, also known as UK, is a public co-educational university and is one of the state's two land-grant universities, located in Lexington, Kentucky... , excavated the site from 1977 to 1985. A coastal migration could explain how people arrived in Monte Verde. 2000, archaeologists say people were living at Cactus Hill Cactus Hill Cactus Hill is an archaeological site in southeastern Virginia, United States. The site sits on sand dunes above the Nottoway River and lies about 45 miles south of Richmond. The site is owned by the International Paper Corporation.... , Virginia Virginia The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there... where stone tools and charcoal from a fire pit are found.
15,000–13,000 years ago: The Taima Taima mastodon kill/butchering site in Falcon Falcon A falcon is any species of raptor in the genus Falco. The genus contains 37 species, widely distributed throughout Europe, Asia, and North America.... , Venezuela Venezuela Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south... was first excavated by J.M. Cruxent in the 1960s and 1970s. It is one of the earliest archaeological sites that is pre-Clovis. In 1976 a broken El Jobo point (red arrow) was found inside the pubic cavity of a partially disarticulated and butchered young mastodon whose bones had been cut, with a jasper flake found near the left ulna Ulna The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form... of the animal. Peñon women found by an ancient lake bed near Mexico City Mexico City Mexico City is the Federal District , capital of Mexico and seat of the federal powers of the Mexican Union. It is a federal entity within Mexico which is not part of any one of the 31 Mexican states but belongs to the federation as a whole... in 1959. El Abra El Abra El Abra is an archaeological excavation site, located in the valley of the same name, east of the city of Zipaquirá, department Cundinamarca, Colombia; in the Altiplano Cundiboyacense, at an altitude of 2,570 m... sites located in the valley east of the city of Zipaquirá Zipaquirá Zipaquirá is a municipality and city of Colombia in the department of Cundinamarca. Its neighboring municipalities are Tausa and Cogua to the north; Nemocón, Gachancipá and Sopó to the east; Cajicá and Tabio to the south; and Subachoque and Pacho to the west. Its seat of municipal government is 49... , Colombia Colombia Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the... . First excavated by Gonzalo Correal and associates in the late 1970s and early 1980s. 3,072 pieces found indicate it was inhabited continuously for over 7,000 years. At Paisley Caves Paisley Caves The Paisley Caves complex is a system of four caves in an arid, desolate region of south-central Oregon, United States. One of the caves may contain archaeological evidence of the oldest definitively-dated human presence in North America. The site was first studied by archeologists in the 1930s... in the Cascade Range of Oregon Oregon Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern... , archaeologists find a scattering of human coprolites, or fossil feces in 2003. The mitochondrial DNA extracted from coprolites linked the cave dwellers to two genetic groups of early Americans that arose 14,000 to 18,000 years ago. These two genetic groups were the founding Paleo-Indians and later Na-Dené Na-Dené languages Na-Dene is a Native American language family which includes at least the Athabaskan languages, Eyak, and Tlingit languages. An inclusion of Haida is controversial.... migration.
13,500 – 12,000 years ago: The Ice Age is ending, melting glaciers have raised sea levels 120 meters and submerged the land bridge between Alaska and Siberia. Geologic evidence indicates that by 11,500 years ago, the Cordilleran Cordilleran Ice Sheet The Cordilleran ice sheet was a major ice sheet that covered, during glacial periods of the Quaternary, a large area of North America. This included the following areas:Western MontanaThe Idaho Panhandle... and Laurentide ice sheets had retreated far enough to open a habitable ice-free corridor between them. The exposed land was dry and probably restored enough to support plants and animals, which the migrating hunter-gatherer followed. Clovis theory – People were living near Clovis, New Mexico Clovis, New Mexico Clovis is the county seat of Curry County, New Mexico, United States. Its population was 32,667 at the 2000 census; according to 2010 Census Bureau estimates, the population had risen to 37,775.... where tools from this era were found in the 1930s. This find gave rise to the widely held "Clovis First" theory that people spread through the Americas only after the Ice Age. The Clovis culture was believed replaced by several more localized regional cultures, such as the Folsom tradition Folsom tradition The Folsom Complex is a name given by archaeologists to a specific Paleo-Indian archaeological culture that occupied much of central North America... , from the time of the Younger Dryas Younger Dryas The Younger Dryas stadial, also referred to as the Big Freeze, was a geologically brief period of cold climatic conditions and drought between approximately 12.8 and 11.5 ka BP, or 12,800 and 11,500 years before present... cold climate period. Peru Peru Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean.... coastal region inhabitants fished with nets and bone hooks, collecting seafood such as crabs and sea urchins.
12,000–10,000 years ago: Ice age over, climate similar to present temperatures. Old migration theories believe first widespread migration in South America and subsequently a dramatic rise in population all over the Americas, introduced in the 1930s. The Maritimes Maritimes The Maritime provinces, also called the Maritimes or the Canadian Maritimes, is a region of Eastern Canada consisting of three provinces, New Brunswick, Nova Scotia, and Prince Edward Island. On the Atlantic coast, the Maritimes are a subregion of Atlantic Canada, which also includes the... of Canada are settled by Paleo-Indians. Sites in and around Belmont, Nova Scotia Belmont, Nova Scotia Belmont is a community in the Canadian province of Nova Scotia, located in Colchester County.-References:*... have evidence indicating small seasonal hunting camps, perhaps re-visited over many generations. Luzia Woman Luzia Woman right\|thumb\|250px\|Reconstruction of her faceLuzia Woman is the name for the skeleton of a woman found in a cave in Brazil, South America. Some archaeologists believe the young woman may have been part of the first wave of immigrants to South America... 's skull and other bones excavated in the Lagoa Santa Lagoa Santa For Lagoa Santa, a municipality in Goiás see Lagoa Santa, GoiásLagoa Santa is a municipality and region in the state of Minas Gerais, Brazil... , Brazil area by French archaeologist Annette Laming-Emperaire Annette Laming-Emperaire Annette Laming-Emperaire was a French archeologist.Born in Petrograd, Annette Laming studied philosophy in Paris until World War II began. She then turned to teaching while participating in the French Resistance... in the 1970s. By 2006, Lagoa Santa sites had produced no fewer than 75 well-preserved ancient skulls. 1994, University of California, Riverside anthropologist R. Erv Taylor examined seventeen of the Spirit Cave artifacts near Fallon, Nevada Fallon, Nevada -Demographics:As of the census of 2000, there were 7,536 people, 3,004 households, and 1,877 families residing in the city. The population density was 2,474.1 people per square mile . There were 3,336 housing units at an average density of 1,095.2 per square mile... from the 1940s using mass spectrometry. The results indicated that a mummy Mummy A mummy is a body, human or animal, whose skin and organs have been preserved by either intentional or incidental exposure to chemicals, extreme coldness , very low humidity, or lack of air when bodies are submerged in bogs, so that the recovered body will not decay further if kept in cool and dry... was approximately 9,400–10,200 years old — older than any previously known North American mummy. Unique markers found in DNA recovered from an Alaskan tooth were found in specific coastal tribes, and were rare in any of the other indigenous peoples in the Americas. This finding lends substantial credence to a migration theory that at least one set of early peoples moved south along the west coast of the Americas in boats.
9,000–8,000 years ago: Remains, known as Kennewick Man Kennewick Man Kennewick Man is the name for the skeletal remains of a prehistoric man found on a bank of the Columbia River in Kennewick, Washington, USA, on July 28, 1996... , are found in 1996 on the Columbia River Columbia River The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state... near Kennewick, Washington Kennewick, Washington Kennewick is a city in Benton County in the southeastern part of the U.S. state of Washington, near the Hanford nuclear site. It is the most populous of the three cities collectively referred to as the Tri-Cities... . A skull and more than 300 bones and bone fragments were found at the site, making up among the oldest, best preserved, and most complete human remains ever found in North America. Initial radiocarbon dating indicated the remains were between 7,000 and 9,500 years old. A leaf-shaped projectile found on the body was long, broad and had serrated edges, all fitting the definition of a Cascade point Cascade point A Cascade point is a projectile point associated with the Cascade phase, an ancient culture of Native Americans that settled in the Pacific Northwest that existed from 9000 or 10000 BC until about 5500 BC.... . This type of point is a feature of the Cascade phase, occurring in the archaeological record from roughly 6,000 to over 8,500 years ago. 1930s-1990s no major Central American archaeological sites that go back more than 9,000 years have been found. Isolated finds of stone tools in Belize Belize Belize is a constitutional monarchy and the northernmost country in Central America. Belize has a diverse society, comprising many cultures and languages. Even though Kriol and Spanish are spoken among the population, Belize is the only country in Central America where English is the official... , Nicaragua Nicaragua Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean... and Costa Rica Costa Rica Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east.... indicate that such sites almost certainly exist. Lack of funding for exploration in the areas has postponed likely finds. Tehuacan Valley of Mexico – people are living in rock shelters and using stone cooking pots, which were left in the center of the hearth. Maize was cultivated to be used in the same valley between 7,000–6,000 years ago.

Genetics and blood type

By the 1920s studies indicated that blood type O was predominated in pre-Columbian populations, with a small admixture of type A in the north. Further blood studies combining statistics and genetic research were pioneered by Luigi Cavalli-Sforza and applied to population migrations predating historical records. This led Jacob Bronowski

Jacob Bronowski

Jacob Bronowski was a Polish-Jewish British mathematician, biologist, historian of science, theatre author, poet and inventor...

to assert in 1973 (in The Ascent of Man
The Ascent of Man
The Ascent of Man is a thirteen-part documentary television series produced by the BBC and Time-Life Films first transmitted in 1973, written and presented by Jacob Bronowski...

) that there were at least two separate migrations:

"I can see no sensible way of interpreting that but to believe that a first migration of a small, related kinship group (all of blood group O) came into America, multiplied, and spread right to the South. Then a second migration, again of small groups, this time containing either A alone or both A and O, followed them only as far as North America."

Modern Amerindian genetics studies focus primarily on Human Y-chromosome DNA haplogroups

Human Y-chromosome DNA haplogroups

In human genetics, a Human Y-chromosome DNA haplogroup is a haplogroup defined by differences in the non-recombining portions of DNA from the Y chromosome ....

and Human mitochondrial DNA haplogroups

Human mitochondrial DNA haplogroups

In human genetics, a human mitochondrial DNA haplogroup is a haplogroup defined by differences in human mitochondrial DNA. Haplogroups are used to represent the major branch points on the mitochondrial phylogenetic tree...

. The genetic pattern emerging shows two very distinctive genetic episodes occurred, first with the initial peopling of the Americas

Americas

, and secondly with European colonization of the Americas

European colonization of the Americas

The start of the European colonization of the Americas is typically dated to 1492. The first Europeans to reach the Americas were the Vikings during the 11th century, who established several colonies in Greenland and one short-lived settlement in present day Newfoundland...

. The former is the determinant factor for the number of gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

lineages, zygosity

Zygosity

Zygosity refers to the similarity of alleles for a trait in an organism. If both alleles are the same, the organism is homozygous for the trait. If both alleles are different, the organism is heterozygous for that trait...

mutations and founding haplotype

Haplotype

A haplotype in genetics is a combination of alleles at adjacent locations on the chromosome that are transmitted together...

s present in today's indigenous Amerindian populations

Population history of American indigenous peoples

The population figures for Indigenous peoples in the Americas before the 1492 voyage of Christopher Columbus have proven difficult to establish and rely on archaeological data and written records from European settlers...

.

Genetics and blood studies indicate human settlement of the New World

New World

The New World is one of the names used for the Western Hemisphere, specifically America and sometimes Oceania . The term originated in the late 15th century, when America had been recently discovered by European explorers, expanding the geographical horizon of the people of the European middle...

occurred in stages from the Bering sea coastline

Bering Sea

The Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves....

, with an initial layover on Beringia for the small founding population

Founder effect

. The micro-satellite 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

Inuit

The Inuit are a group of culturally similar indigenous peoples inhabiting the Arctic regions of Canada , Denmark , Russia and the United States . Inuit means “the people” in the Inuktitut language...

and Indigenous Alaskan

Alaska Natives

Alaska Natives are the indigenous peoples of Alaska. They include: Aleut, Inuit, Tlingit, Haida, Tsimshian, Eyak, and a number of Northern Athabaskan cultures.-History:In 1912 the Alaska Native Brotherhood was founded...

populations exhibit haplogroup Q (Y-DNA)

Haplogroup Q (Y-DNA)

In human genetics, Haplogroup Q is a Y-chromosome DNA haplogroup.-Origins:Haplogroup Q is one of the two branches of haplogroup P . Haplogroup Q is believed to have arisen in Central Asia approximately 15,000 to 20,000 years ago. It has had multiple origins proposed...

mutations, but are distinct from other indigenous Amerindians with various mtDNA and atDNA mutations. This suggests that the earliest migrants into the northern extremes of North America and Greenland

Greenland

Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...

derived from later migrant populations.

Land bridge theory

Also known as the Bering Strait Theory or Beringia theory, the Land Bridge theory has been widely accepted since the 1930s. The idea was first postulated in a rudimentary fashion in 1590 by the Jesuit scholar José de Acosta

José de Acosta

José de Acosta was a Spanish 16th-century Jesuit missionary and naturalist in Latin America.-Life:...

. This model of migration into the New World

History of the west coast of North America

The human history of the west coast of North America is believed to stretch back to the arrival of the earliest people over the Bering Strait, or alternately along a now-submerged coastal plain, through the development of significant pre-Columbian cultures and population densities, to the arrival...

proposes that people migrated from Siberia

Siberia

Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...

into Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

, tracking big game animal herd

Herd

Herd refers to a social grouping of certain animals of the same species, either wild or domestic, and also to the form of collective animal behavior associated with this or as a verb, to herd, to its control by another species such as humans or dogs.The term herd is generally applied to mammals,...

s. They were able to cross between the two continents by a land bridge called the Bering Land Bridge

Bering land bridge

The Bering land bridge was a land bridge roughly 1,000 miles wide at its greatest extent, which joined present-day Alaska and eastern Siberia at various times during the Pleistocene ice ages. Like most of Siberia and all of Manchuria, Beringia was not glaciated because snowfall was extremely light...

, which spanned what is now the Bering Strait

Bering Strait

The Bering Strait , known to natives as Imakpik, is a sea strait between Cape Dezhnev, Chukotka Autonomous Okrug, Russia, the easternmost point of the Asian continent and Cape Prince of Wales, Alaska, USA, the westernmost point of the North American continent, with latitude of about 65°40'N,...

, during the Wisconsin glaciation

Wisconsin glaciation

The last glacial period was the most recent glacial period within the current ice age occurring during the last years of the Pleistocene, from approximately 110,000 to 10,000 years ago....

, the last major stage of the Pleistocene

Pleistocene

The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

beginning 50,000 years ago and ending some 10,000 years ago, when ocean levels were 60 metres (196.9 ft) lower than today. This information is gathered using oxygen isotope

Isotopes of oxygen

There are three stable isotopes of oxygen that lead to oxygen having a standard atomic mass of 15.9994 u. 17 radioactive isotopes have also been characterized, with mass numbers from 12O to 28O, all short-lived, with the longest-lived being 15O with a half-life of 122.24 seconds...

records from deep-sea cores

Core sample

A core sample is a cylindrical section of a naturally occurring substance. Most core samples are obtained by drilling with special drills into the substance, for example sediment or rock, with a hollow steel tube called a core drill. The hole made for the core sample is called the "core hole". A...

. An exposed land bridge that was at least 1,000 miles wide existed between Siberia and the western coast of Alaska. In the "short chronology" version, from the archaeological evidence gathered, it was concluded that this culture of big game hunters crossed the Bering Strait at least 12,000 years ago and could have eventually reached the southern tip of South America by 11,000 years ago.

Synopsis

At some point during the last Ice Age

Ice age

An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...

, about 17,000 years ago, as the ice sheets advanced and sea levels fell, people first migrated from the Eurasian landmass to the Americas. These nomad

Nomad

Nomadic people , commonly known as itinerants in modern-day contexts, are communities of people who move from one place to another, rather than settling permanently in one location. There are an estimated 30-40 million nomads in the world. Many cultures have traditionally been nomadic, but...

ic hunters were following game herds from Siberia

Siberia

across what is today the Bering Strait

Bering Strait

into Alaska

Alaska

, and then gradually spread southward. Based upon the distribution of Amerind languages and language families

Language family

A language family is a group of languages related through descent from a common ancestor, called the proto-language of that family. The term 'family' comes from the tree model of language origination in historical linguistics, which makes use of a metaphor comparing languages to people in a...

, a movement of tribes along the Rocky Mountain

Rocky Mountains

foothills and eastward across the Great Plains

Great Plains

The Great Plains are a broad expanse of flat land, much of it covered in prairie, steppe and grassland, which lies west of the Mississippi River and east of the Rocky Mountains in the United States and Canada. This area covers parts of the U.S...

to the Atlantic seaboard is assumed to have occurred at least some 13,000 to 10,000 years ago.

Clovis culture

This big game-hunting culture has been labeled the Clovis culture, and is primarily identified by its artifacts of fluted projectile points. The culture received its name from artifacts found near Clovis, New Mexico

Clovis, New Mexico

Clovis is the county seat of Curry County, New Mexico, United States. Its population was 32,667 at the 2000 census; according to 2010 Census Bureau estimates, the population had risen to 37,775....

, the first evidence of this tool complex, excavated in 1932. The Clovis culture ranged over much of North America and appeared in South America. The culture is identified by distinctive "Clovis point", a flaked flint spear-point with a notched flute by which it was inserted into a shaft; it could be removed from the shaft for traveling. This flute is one characteristic that defines the Clovis point complex.

Dating of Clovis materials has been by association with animal bones and by the use of carbon dating methods. Recent reexaminations of Clovis materials using improved carbon-dating methods produced results of 11,050 and 10,800 radiocarbon years B.P. (before present

Before Present

Before Present years is a time scale used in archaeology, geology, and other scientific disciplines to specify when events in the past occurred. Because the "present" time changes, standard practice is to use AD 1950 as the origin of the age scale, reflecting the fact that radiocarbon...

). This evidence suggests that the culture flowered somewhat later and for a shorter period of time than previously believed. Michael R. Waters of Texas A&M University

Texas A&M University

Texas A&M University is a coeducational public research university located in College Station, Texas . It is the flagship institution of the Texas A&M University System. The sixth-largest university in the United States, A&M's enrollment for Fall 2011 was over 50,000 for the first time in school...

in College Station and Thomas W. Stafford Jr., proprietor of a private-sector laboratory in Lafayette, Colorado

Lafayette, Colorado

The City of Lafayette is a Home Rule Municipality located in Boulder County, Colorado, United States. The United States Census Bureau estimates that the city population was 23,884 on 2005-07-01.- Geography :Lafayette is located at ....

and an expert in radiocarbon dating, attempted to determine the dates of the Clovis period. The heyday of Clovis technology has typically been set between 11,500 and 10,900 radiocarbon years B.P. (The radiocarbon calibration is disputed for this period, but the widely used IntCal04 calibration puts the dates at 13,300 to 12,800 calendar years B.P.). In a controversial move, Waters and Stafford conclude that no fewer than 11 of the 22 Clovis sites with radiocarbon dates are "problematic" and should be disregarded—including the type site

Type site

In archaeology a type site is a site that is considered the model of a particular archaeological culture...

in Clovis, New Mexico. They argue that the datable samples could have been contaminated by earlier material. This contention was considered highly controversial by many in the archaeological community.

Clovis-type artifacts seem to disappear from the archaeological record after the hypothesized Younger Dryas impact event

Younger Dryas impact event

The Younger Dryas impact hypothesis or Clovis comet hypothesis was the hypothesized large air burst or earth impact of an object or objects from outer space that initiated the Younger Dryas cold period about 12,900 BP calibrated ....

, roughly 12,900 years before the present. The effects of the event possibly caused a decline in post-Clovis human populations and shifts in culture and behavior patterns.

Problems with Clovis migration models

Significant problems arise with the Clovis migration model. If Clovis people radiated south after entering the New World and eventually reached the southern tip of South America by 11,000 years ago, this leaves only a short time span to populate the entire hemisphere. Another complication for the Clovis-only theory arose in 1997, when a panel of authorities inspected the Monte Verde

Monte Verde

Monte Verde is an archaeological site in southern Chile, located in the northern Patagonia near Puerto Montt, Chile, which has been dated to 14,800 years BP . This dating adds to the evidence showing that settlement in the Americas pre-dates the Clovis culture by roughly 1000 years...

site in Chile

Chile

Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

They concluded that the radiocarbon evidence predates Clovis sites in the North American Midwest by at least 1,000 years. This supports the theory of a primary coastal migration route by which people moved south along the coastline faster than those who migrated inland into the central areas of the Americas. Many excavations have uncovered evidence that subsistence patterns of early Americans included foods such as turtle

Turtle

Turtles are reptiles of the order Testudines , characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield...

s, shellfish

Shellfish

Shellfish is a culinary and fisheries term for exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. Although most kinds of shellfish are harvested from saltwater environments, some kinds are found only in freshwater...

, and tuber

Tuber

Tubers are various types of modified plant structures that are enlarged to store nutrients. They are used by plants to survive the winter or dry months and provide energy and nutrients for regrowth during the next growing season and they are a means of asexual reproduction...

s. This is a change of diet from the big game mammoth

Mammoth

A mammoth is any species of the extinct genus Mammuthus. These proboscideans are members of Elephantidae, the family of elephants and mammoths, and close relatives of modern elephants. They were often equipped with long curved tusks and, in northern species, a covering of long hair...

s, long-horn bison

Bison

Members of the genus Bison are large, even-toed ungulates within the subfamily Bovinae. Two extant and four extinct species are recognized...

, horse

Horse

The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...

, and camel

Camel

A camel is an even-toed ungulate within the genus Camelus, bearing distinctive fatty deposits known as humps on its back. There are two species of camels: the dromedary or Arabian camel has a single hump, and the bactrian has two humps. Dromedaries are native to the dry desert areas of West Asia,...

s which early Clovis hunters apparently followed east into the New World.

At the Topper

Topper (archaeological site)

Topper is an archaeological site located along the Savannah River in Allendale County, South Carolina in the United States. It is noted as the location of controversial artifacts believed by some archaeologists to indicate human habitation of the New World earlier than the Clovis culture,...

archaeological site

Archaeological site

An archaeological site is a place in which evidence of past activity is preserved , and which has been, or may be, investigated using the discipline of archaeology and represents a part of the archaeological record.Beyond this, the definition and geographical extent of a 'site' can vary widely,...

(located along the banks of the Savannah River

Savannah River

The Savannah River is a major river in the southeastern United States, forming most of the border between the states of South Carolina and Georgia. Two tributaries of the Savannah, the Tugaloo River and the Chattooga River, form the northernmost part of the border...

near Allendale, South Carolina

Allendale, South Carolina

Allendale is a town in Allendale County, South Carolina, United States. The population was 4,052 at the 2000 census. It is the county seat of Allendale County.-Geography:...

) investigated by University of South Carolina

University of South Carolina

The University of South Carolina is a public, co-educational research university located in Columbia, South Carolina, United States, with 7 surrounding satellite campuses. Its historic campus covers over in downtown Columbia not far from the South Carolina State House...

archaeologist Dr. Albert Goodyear

Albert Goodyear

Albert C. Goodyear III is an archaeologist who is founder and director of the Allendale PaleoIndian Expedition in South Carolina, where he has unearthed controversial evidence that may greatly move back the date of occupation of North America by humans to 50,000 years or more before the present...

, charcoal

Charcoal

Charcoal is the dark grey residue consisting of carbon, and any remaining ash, obtained by removing water and other volatile constituents from animal and vegetation substances. Charcoal is usually produced by slow pyrolysis, the heating of wood or other substances in the absence of oxygen...

material recovered in association with purported human artifacts returned radiocarbon dates

Radiocarbon dating

Radiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...

of up to 50,000 years BP

Before Present

. This would indicate the presence of humans well before the last glacial period. Considerable doubt over the validity of these findings has been raised by many other researchers, and the pre-Clovis Topper dates remain controversial. Charcoal could have originated from forest fires, and the crude stone artifacts may be misinterpreted geofacts.

Pre-Clovis dates have been claimed for several sites in South America, but these early dates have yet to be verified unequivocally.

Discoveries in 2002 and 2003 of human coprolites (fossilized feces) found deeply buried in an Oregon cave indicate the presence of humans in North America as much as 1,200 years prior to the Clovis culture.

Watercraft migration theories

Earlier finds have led to a pre-Clovis culture

Clovis culture

theory encompassing different migration models with an expanded chronology to supersede the "Clovis-first" theory.

Pacific coastal models

Pacific models propose that people reached the Americas via water travel, following coastlines from northeast Asia into the Americas. Coastlines are unusually productive environments because they provide humans with access to a diverse array of plants and animals from both terrestrial and marine ecosystems. While not exclusive of land-based migrations, the Pacific 'coastal migration theory' helps explain how early colonists reached areas extremely distant from the Bering Strait region, including sites such as Monte Verde

Monte Verde

in southern Chile and Taima-Taima in western Venezuela

Venezuela

Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...

. Two cultural components were discovered at Monte Verde near the Pacific Coast of Chile. The youngest layer is radiocarbon dated at 12,500 radiocarbon years (~14,000 cal BP) and has produced the remains of several types of seaweeds collected from coastal habitats. The older and more controversial component may date back as far as 33,000 years, but few scholars currently accept this very early component.

Other coastal models, dealing specifically with the peopling of the Pacific Northwest

Pacific Northwest

The Pacific Northwest is a region in northwestern North America, bounded by the Pacific Ocean to the west and, loosely, by the Rocky Mountains on the east. Definitions of the region vary and there is no commonly agreed upon boundary, even among Pacific Northwesterners. A common concept of the...

and California coasts, have been advocated by archaeologists Knut Fladmark, Roy Carlson, James Dixon, Jon Erlandson, Ruth Gruhn, and Daryl Fedje. In a 2007 article in the Journal of Island and Coastal Archaeology, Erlandson and his colleagues proposed a corollary to the coastal migration theory—the "kelp highway hypothesis"—arguing that productive kelp

Kelp

Kelps are large seaweeds belonging to the brown algae in the order Laminariales. There are about 30 different genera....

forests supporting similar suites of plants and animals would have existed near the end of the Pleistocene around much of the Pacific Rim from Japan to Beringia, the Pacific Northwest, and California, as well as the Andean Coast of South America. Once the coastlines of Alaska and British Columbia had deglaciated about 16,000 years ago, these kelp forest (along with estuarine, mangrove, and coral reef) habitats would have provided an ecologically similar migration corridor, entirely at sea level, and essentially unobstructed.

Southeast Asians: Paleoindians of the Coast

The boat-builders from Southeast Asia may have been one of the earliest groups to reach the shores of North America. One theory suggests people in boats followed the coastline from the Kurile Islands to Alaska

Alaska

down the coasts of North and South America as far as Chile

Chile

[2 62; 7 54, 57]. The Haida nation on the Queen Charlotte Islands

Queen Charlotte Islands

Haida Gwaii , formerly the Queen Charlotte Islands, is an archipelago on the North Coast of British Columbia, Canada. Haida Gwaii consists of two main islands: Graham Island in the north, and Moresby Island in the south, along with approximately 150 smaller islands with a total landmass of...

off the coast of British Columbia

British Columbia

British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...

may have originated from these early Asian mariners between 25,000 and 12,000. Early watercraft migration would also explain the habitation of coastal sites in South America such as Pikimachay Cave

Pikimachay

Pikimachay is an archaeological site in the Ayacucho Valley of Peru. Radiocarbon dates from this cave give a human precence ranging from 22,200 to 14,700 years ago, but this evidence has been disputed and a more conservative date 12,000 BCE seems possible.Richard S. MacNeish was the first...

in Peru

Peru

Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

by 20,000 years ago and Monte Verde

Monte Verde

in Chile

Chile

by 13,000 years ago [6 30; 8 383].

"'There was boat use in Japan 20,000 years ago,' says Jon Erlandson, a University of Oregon

University of Oregon

-Colleges and schools:The University of Oregon is organized into eight schools and colleges—six professional schools and colleges, an Arts and Sciences College and an Honors College.- School of Architecture and Allied Arts :...

anthropologist. 'The Kurile Islands (north of Japan) are like stepping stones to Beringia,' the then continuous land bridging the Bering Strait. Migrants, he said, could have then skirted the tidewater glaciers in Canada right on down the coast." [7 64]'

Atlantic coastal model

Archaeologists Dennis Stanford

Dennis Stanford

Dennis J. Stanford in Cherokee, Iowa is an archaeologist and Director of the Paleo-Indian Program at the National Museum of Natural History at the Smithsonian Institution. Along with Prof...

and Bruce Bradley champion the coastal Atlantic route. Their Solutrean Hypothesis

Solutrean hypothesis

The Solutrean hypothesis proposes that peoples from Europe may have been among the earliest settlers in the Americas, as evidenced by similarities in stone tool technology of the Solutrean culture from prehistoric Europe to that of the later Clovis tool-making culture found in the Americas. It was...

is also based on evidence from the Clovis complex, but instead traces the origins of the Clovis toolmaking style to the Solutrean

Solutrean

The Solutrean industry is a relatively advanced flint tool-making style of the Upper Palaeolithic, from around 22,000 to 17,000 BP.-Details:...

culture of Ice Age Western Europe. The theory suggests that early European people (or peoples) may have been among the earliest settlers of the Americas. Citing evidence that the Solutrean culture of prehistoric Europe may have provided the basis for the tool-making of the Clovis culture

Clovis culture

in the Americas, the theory suggests that Ice Age

Ice age

Europeans migrated to North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

by using skills similar to those possessed by the modern Inuit

Inuit

peoples and followed the edge of the ice sheet that spanned the Atlantic. The hypothesis rests upon particular similarities in Solutrean and Clovis technology that have no known counterparts in Eastern Asia, Siberia

Siberia

or Beringia, areas from which, or through which, early Americans are known to have migrated. The theory is largely discounted by most professionals for a variety of reasons, including the fact that the differences between the two tool-making traditions far outweigh the similarities, the several thousand miles of the Atlantic Ocean to be crossed, and the 5000-year-span that separate the two different cultures. Genetic studies of Native American populations have also shown the Solutrean theory to be unlikely, showing instead that the five main mtDNA haplogroups found in the Americas were all part of one gene pool migration from Asia.

Problems with evaluating coastal migration models

The coastal migration models provide a different perspective on migration to the New World, but they are not without their own problems. One of the biggest problems is that global sea levels have risen over 100 metres since the end of the last glacial period, and this has submerged the ancient coastlines which maritime people would have followed into the Americas. Finding sites associated with early coastal migrations is extremely difficult—and systematic excavation of any sites found in deeper waters is challenging and expensive. If there was an early pre-Clovis coastal migration, there is always the possibility of a "failed colonization." Another problem that arises is the lack of hard evidence found for a "long chronology" theory. No sites have yet produced a consistent chronology older than about 12,500 radiocarbon years (~14,500 calendar years) , but research has been limited in South America related to the possibility of early coastal migrations.

Sources

Dixon, E. James. Quest for the Origins of the First Americans. University of New Mexico Press. 1993.
Dixon, E. James. Bones, Boats, and Bison: the Early Archeology of Western North America. University of New Mexico Press. 1993.
Erlandson, Jon M. Early Hunter-Gatherers of the California Coast. Plenum Press. 1994.
Erlandson, Jon M. The Archaeology of Aquatic Adaptations: Paradigms for a New Millennium. Journal of Archaeological Research, Vo. 9, 2001. pp. 287–350.
Erlandson, Jon M. Anatomically Modern Humans, Maritime Migrations, and the Peopling of the New World. In The First Americans: The Pleistocene Colonization of the New World, edited by N. Jablonski, 2002. pp. 59–92. Memoirs of the California Academy of Sciences. San Francisco.
Erlandson, Jon. M., M. H. Graham, Bruce J. Bourque, Debra Corbett, James A. Estes, & R. S. Steneck. The Kelp Highway Hypothesis: Marine Ecology, The Coastal Migration Theory, and the Peopling of the Americas. Journal of Island and Coastal Archaeology, Vo. 2, 2007. pp. 161–174.
Jason A. Eshleman, Ripan S. Malhi, and David Glenn Smith, "Mitochondrial DNA Studies of Native Americans: Conceptions and Misconceptions of the Population Prehistory of the Americas", Evolutionary Anthropology, 12:7–18 (2003)
Fedje, & Christensen. Modeling Paleoshorelines and Locating Early Holocene Coastal Sites in Haida Gwaii. American Antiquity, Vol. 64, #4, 1999. pp. 635–652.
E. F. Greenman, "The Upper Palaeolithic and the New World", Current Anthropology, 4: 41–66 (1963)
Jody Hey, "On the Number of New World Founders: A Population Genetic Portrait of the Peopling of the Americas", Public Library of Science Biology, 3(6):e193 (2005).
Jones, Peter N. Respect for the Ancestors: American Indian Cultural Affiliation in the American West. Bauu Institute Press. 2005.
Matson and Coupland. The Prehistory of the Northwest Coast. Academic Press. New York. 1995.
Bradley, Michael, "The Black Discovery Of America: Amazing evidence of daring voyages by ancient West African mariners" Toronto, Canada: Personal Library Publishers, 1981 ISBN 0-920510-36-1.
Adovasio, J. M., with Jake Page. The First Americans: In Pursuit of Archaeology's Greatest Mystery. New York: Random House, 2002.
Lauber, Patricia. Who Came First? New Clues to Prehistoric Americans. Washington, D.C.: National Geographic Society, 2003.
Snow, Dean R. "The First Americans and the Differentiation of Hunter-Gatherer Cultures." In Bruce G. Trigger and Wilcomb *E. Washburn, eds., The Cambridge History of the Native Peoples of the Americas, Volume I: North America (Cambridge: Cambridge University Press
Cambridge University Press
Cambridge University Press is the publishing business of the University of Cambridge. Granted letters patent by Henry VIII in 1534, it is the world's oldest publishing house, and the second largest university press in the world...

, 1996), 125-199.
Jones, Peter N. "Respect for the Ancestors: American Indian Cultural Affiliation in the American West." Boulder, Colorado: Bauu Press. 2004
Dixon, E. James. Bones, Boats and Bison: the Early Archeology of Western North America. University of New Mexico Press. 1999.
Evidence Supports Earlier Date for People in North America, April 4, 2008

External links

Journey of Man: A Genetic Odyssey (movie) - by Spencer Wells
Spencer Wells
Spencer Wells is a geneticist and anthropologist, an at the National Geographic Society, and Frank H.T. Rhodes Class of '56 Professor at Cornell University. He leads The Genographic Project.-Education:...

- PBS and National Geographic Channel
National Geographic Channel
National Geographic Channel, also commercially abbreviated and trademarked as Nat Geo, is a subscription television channel that airs non-fiction television programs produced by the National Geographic Society. Like History and the Discovery Channel, the channel features documentaries with factual...

, 2003 - 120 Minutes, UPC/EAN: 841887001267
Atlas of the Human Journey, Genographic Project, National Geographic
An mtDNA view of the peopling of the world by Homo sapiens Cambridge DNA's
Journey of Mankind - Genetic Map – Bradshaw Foundation
John Robinson (sculptor)
John Robinson was a British sculptor and co-founder of the . Accounts of his work may be seen at the , the website of the and the June and July 2007, issues of...
The Paleoindian Period – United States Department of the Interior, National Park Service
National Park Service
The National Park Service is the U.S. federal agency that manages all national parks, many national monuments, and other conservation and historical properties with various title designations...
Alabama Archaeology: Prehistoric Alabama – The University of Alabama, Department of Archaeology
University of Alabama
The University of Alabama is a public coeducational university located in Tuscaloosa, Alabama, United States....
The Paleoindian Database – The University of Tennessee, Department of Anthropology
University of Tennessee
The University of Tennessee is a public land-grant university headquartered at Knoxville, Tennessee, United States...

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Paleoindians and the Great Pleistocene Die-Off – American Academy of Arts and Sciences, National Humanities Center
National Humanities Center
The National Humanities Center is an independent institute for advanced study in the humanities. It is the only major independent institute for advanced study in all fields of the humanities in the United States. The NHC operates as a privately incorporated nonprofit and is not part of any...

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Understanding the debate

Timeline of selected archaeological, geological and genetic evidence

Genetics and blood type

Land bridge theory

Synopsis

Clovis culture

Problems with Clovis migration models

Watercraft migration theories

Pacific coastal models

Southeast Asians: Paleoindians of the Coast

Atlantic coastal model

Problems with evaluating coastal migration models

Sources

Further reading

External links