Mitochondrial DNA and Y chromosome diversity and the peopling of the Americas: evolutionary and demographic evidence.

Source

Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. tgschurr@sas.upenn.edu

Abstract

A number of important insights into the peopling of the New World have been gained through molecular genetic studies of Siberian and Native American populations. While there is no complete agreement on the interpretation of the mitochondrial DNA (mtDNA) and Y chromosome (NRY) data from these groups, several generalizations can be made.

To begin with, the primary migration of ancestral Asians expanded from south-central Siberia into the New World and gave rise to ancestral Amerindians. The initial migration seems to have occurred between 20,000-15,000 calendar years before present (cal BP), i.e., before the emergence of Clovis lithic sites (13,350-12,895 cal BP) in North America.

Because an interior route through northern North America was unavailable for human passage until 12,550 cal BP, after the last glacial maximum (LGM), these ancestral groups must have used a coastal route to reach South America by 14,675 cal BP, the date of the Monte Verde site in southern Chile. The initial migration appears to have brought mtDNA haplogroups A-D and NRY haplogroups P-M45a and Q-242/Q-M3 to the New World, with these genetic lineages becoming widespread in the Americas.

A second expansion that perhaps coincided with the opening of the ice-free corridor probably brought mtDNA haplogroup X and NRY haplogroups P-M45b, C-M130, and R1a1-M17 to North and Central America. Finally, populations that formerly inhabited Beringia expanded into northern North America after the LGM, and gave rise to Eskimo-Aleuts and Na-Dené Indians.

Haplogroup Q1a3a1 (Y-DNA)

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Haplogroup Q1a3a1
Possible time of origin	10 to 15 thousand years ago
Possible place of origin	North America or possibly Siberia
Ancestor	Q1a3a ^[1]
Descendants	Q1a3a1a, Q1a3a1b, Q1a3a1c
Defining mutations	M3 (rs3894)

In human genetics, Haplogroup Q1a3a1 (Y-DNA) (phylogenetic name) and/or Q-M3 (mutational name) is a Y-chromosome DNA haplogroup (Y-DNA).^[2] Haplogroup Q1a3a1 is a subclade of Haplogroup Q. Haplogroup Q1a3a1 was previously known as Haplogroup Q3.

Indigenous Amerindian sub-clade

Further information: Genetic history of indigenous peoples of the Americas and Y-DNA haplogroups in Indigenous peoples of the Americas

Haplogroup Q1a3a1 is one of the few Y Chromosome haplogroup strictly associated with the indigenous peoples of the Americas, along with haplogroup C3b-P39 which is almost exclusively found in North America. This haplogroup is defined by the presence of the rs3894 (M3) single-nucleotide polymorphism (SNP). The M3 SNP is found "downstream" from the M242 SNP. M242 is the defining SNP of the Q Haplogroup. M3 occurred on the Q lineage roughly 10-15 thousand years ago as the migration into the Americas was underway. There is some debate as to on which side of the Bering Strait this mutation occurred, but it definitely happened in the ancestors of the indigenous peoples of the Americas.

Discovery of M3

In 1996 Dr. Peter Underhill and his colleagues at Stanford University first discovered the SNP that was to become known as M3. Later studies completed the genetic bridge by determining that M3 was related to M242-bearing populations found predominately in Central Asia.^[3]

Subgroups

Populations carrying M3 are widespread throughout the Americas. Since the discovery of M3 several subclades of M3 bearing populations have been discovered in the Americas as well. An example is in South America where some populations have a high prevalence of SNP M19 which defines subclade Q1a3a1a. M19 has been detected in 59% of Amazonian Ticuna men and in 10% of Wayuu men.^[4] Subclades Q1a3a1a-c appears to be unique to South American populations and suggests that population isolation and perhaps even the establishment of tribes began soon after migration into the Americas.^[5]

The subclades of Haplogroup Q1a3a with their defining SNP's (in parenthesis):^[6]

Q1a3a1 (M3) - Subclade associated with all Indigenous Americans. Origin: Siberia 15,000 years ago^[1]^[7]
- Q1a3a1a (M19) - subclade found among Indigenous South Americas, such as the Ticuna and the Wayuu.^[7] Origin: South America approximately 5,000 to 10,000 years ago.^[1]
- Q1a3a1b (M194) - It has only been found in South American populations^[7]
- Q1a3a1c (M199, P106, P292) - subclades that have only been found in South American populations^[1]

Genetic history of indigenous peoples of the Americas

A language map with color. Branch lengths are scaled according to genetic distance, but for ease of visualization, a different scale is used on the left and right sides of the middle tick mark at the bottom of the figure. The tree was rooted along the branch connecting the Siberian populations and the Native American populations, and for convenience, the forced bootstrap score of 100% for this rooting is indicated twice. In the neighbor-joining tree, a reasonably well-supported cluster (86%) includes all non-Andean South American populations, together with the Andean-speaking Inga population from southern Colombia. Within this South American cluster, strong support exists for separate clustering of Chibchan–Paezan (97%) and Equatorial–Tucanoan (96%) speakers (except for the inclusion of the Equatorial–Tucanoan Wayuu population with its Chibchan–Paezan geographic neighbors, and the inclusion of Kaingang, the single Ge–Pano–Carib population, with its Equatorial–Tucanoan geographic neighbors). Within the Chibchan–Paezan and Equatorial–Tucanoan subclusters several subgroups have strong support, including Embera and Waunana (96%), Arhuaco and Kogi (100%), Cabecar and Guaymi (100%), and the two Ticuna groups (100%). When the tree-based clustering is repeated with alternate genetic distance measures, despite the high Mantel correlation coefficients between distance matrices (0.98, 0.98, and 0.99 for comparisons of the Nei and Reynolds matrices, the Nei and chord matrices, and the Reynolds and chord matrices, respectively), higher-level groupings tend to differ slightly or to have reduced bootstrap support.

A genetic tree showing some neighbour-joining relationships within Amerindian language groups

Genetic history of indigenous peoples of the Americas primarily focus on Human Y-chromosome DNA haplogroups and Human mitochondrial DNA haplogroups.^[1] Autosomal "atDNA" markers are also used, but differ from mtDNA or Y-DNA in that they overlap significantly.^[2] The genetic pattern indicates Indigenous Amerindians experienced two very distinctive genetic episodes; first with the initial peopling of the Americas, and secondly with European colonization of the Americas.^[3]^[4] The former is the determinant factor for the number of gene lineages, zygosity mutations and founding haplotypes present in today's Indigenous Amerindian populations.^[3]

Human settlement of the New World occurred in stages from the Bering sea coast line, with an initial layover on Beringia for the small founding population.^[5]^[6]^[7] 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.^[8] The Na-Dené, Inuit and Indigenous Alaskan populations exhibit haplogroup Q (Y-DNA); however, they are distinct from other indigenous Amerindians with various mtDNA and atDNA mutations.^[9]^[10]^[11] This suggests that the peoples who first settled the northern extremes of North America and Greenland derived from later migrant populations than those who penetrated further south in the Americas.^[12]^[13] Linguists and biologists have reached a similar conclusion based on analysis of Amerindian language groups and ABO blood group system distributions.^[14]^[15]

Overview

Main articles: Recent African origin of modern humans and Timeline of human evolution

A single-nucleotide polymorphism (SNP) is a change to a single nucleotide in a DNA sequence.

The X and Y human chromosomes are thought to have originated from a pair of identical chromosomes^[16] (300 – 166 million years ago^[17]^[18]^[19]), termed Allosome, when an ancient ancestral mammal developed an allelic variation, a so-called 'sex locus' – simply possessing this allele caused the organism to be male.^[20] The chromosome with this allele became the Y chromosome, while the other member of the pair became the X chromosome. Over time, genes which were beneficial for males and harmful to (or had no effect on) females developed specifically on the Y chromosome, or were acquired through the process of translocation.^[21]

The Y chromosome is passed down exclusively from father to son, all male humans (Y chromosomes) today trace back to a single prehistoric father termed "Y chromosomal Adam" originating from Africa.^[22] The Y chromosome spans about 60 million base pairs (the building blocks of DNA) and represents about 2 percent of the total DNA in all human cells.^[23] The original "Y chromosomal Adam" DNA sequencing has mutated rarely over the 20,000 generations, but each time a new mutation occurs there is a new branch in a haplogroup resulting in a new subclade (single-nucleotide polymorphism (SNP)).^[24] MtDNA mutations are also passed down relatively unchanged from generation to generation; so all humans share the same mtDNA-types, the logical extension of this is that all humans ultimately trace back to one woman, who is commonly referred to as Mitochondrial Eve.^[25]^[26] Both females and males inherit their Mitochondrial DNA (mtDNA) only from their mother.^[27] This line of biological inheritance, therefore, stops with each male.^[28] Consequently, Y-DNA is more commonly used by the general public for tracing genetic heritage.^[28]^[29]^[30]

An autosome (atDNA) is a chromosome that is not a sex chromosome – that is to say there are an equal number of copies of the chromosome in males and females.^[2] Autosomal DNA testing is generally used to determine the "genetic percentages" of a person's ancestry from particular continents/regions or to identify the countries and "tribes" of origin on an overall basis. Genetic admixture tests arrive at these percentages by examining (SNP), which are locations on the DNA where one nucleotide has "mutated" or "switched" to a different nucleotide.^[2] One way to examine the support for particular colonization routes within the American landmass is to determine if a closer relationship between zygosity and geography is observed when “effective” geographic distances are computed along these routes, rather than along shortest-distance paths.^[31]

Y-DNA

For more details on individual Amerindian groups by Y-DNA, see Y-DNA haplogroups in Indigenous peoples of the Americas.

The Y chromosome consortium has established a system of defining Y-DNA haplogroups by letters A through to T, with further subdivisions using numbers and lower case letters.^[32]

Haplogroup Q

For more details on this topic, see Haplogroup Q (Y-DNA).

Spread of Haplogroup Q in Indigenous populations.

Q-M242 (mutational name) is the defining (SNP) of Haplogroup Q (Y-DNA) (phylogenetic name).^[8] Within the Q clade, there are 14 haplogroups marked by 17 SNPs.²⁰⁰⁹^[33]^[34] In Eurasia haplogroup Q-M2 is found among Siberian populations, such as the modern Chukchi and Koryak peoples. In particular two populations exhibit large concentrations of the Q-M242 mutation, the Kets (93.8%) and the Selkups (66.4%).^[35] The Kets are thought to be the only survivors of ancient nomads living in Siberia.^[5] Their population size is very small; there are fewer than 1,500 Kets in Russia.²⁰⁰²^[5] The Selkups have a slightly larger population size than the Kets, with approximately 4,250 individuals. ²⁰⁰²^[8] Starting the Paleo-Indians period, a migration to the Americas across the Bering Strait (Beringia), by a small population carrying the Q-M242 mutation took place.^[36]^[37] A member of this initial population underwent a mutation, which defines its descendant population, known by the Q-M3 (SNP) mutation.^[38] These descendants migrated all over the Americas.^[33]

Q subclades Q1a3a and Q1a3a1a

For more details on Q1a3a and other Q subclades, see Haplogroup Q1a3a (Y-DNA).

Haplogroup Q1a3a (Y-DNA) and/or Q-M3 is defined by the presence of the rs3894 (M3) (SNP).^[3]^[5]^[39] The Q-M3 mutation is roughly 10,000 to 15,000 years old as the initial migration of Paleo-Indians into the Americas occurred.^[7]^[40] Q-M3 is the predominant haplotype in the Americas at a rate of (58%) in South American populations, (50%) in the Na-Dené populations, and in the North American Arctic populations at (46%).^[35] With minimal back-migration of Q-M3 in Eurasia, the mutation likely evolved in east-Beringia, or more specifically the Seward Peninsula or western Alaskan interior. The Beringia land mass began submerging, cutting off land routes.^[6]^[35]^[41]

Since the discovery of Q-M3, several subclades of M3-bearing populations have been discovered. An example is in South America, where some populations have a high prevalence of (SNP) M19 which defines subclade Q1a3a1a.^[42] M19 has been detected in (59%) of Amazonian Ticuna men and in (10%) of Wayuu men.^[42] Subclade M19 appears to be unique to South American Indigenous peoples, arising 5,000 to 10,000 years ago.^[42] This suggests that population isolation and perhaps even the establishment of tribal groups began soon after migration into the South American areas.^[5]^[43]

Haplogroup R1

For more details on this topic, see Haplogroup R1 (Y-DNA).

Spread of Haplogroup R in Indigenous populations.

Haplogroup R1 (Y-DNA) is the second most predominant Y haplotype found among indigenous Amerindians after Q (Y-DNA).^[44] The distribution of R1 is believed to be associated with the re-settlement of Eurasia following the last glacial maximum, and entered the Americas with the initial founding population. R1 is very common throughout all of Eurasia except East Asia and Southeast Asia. R1 (M137) is found predominantly in North American groups like the Ojibwe (79%), Chipewyan (62%), Seminole (50%), Cherokee (47%), Dogrib (40%) and Papago (38%).^[44] The principal-component analysis suggests a close genetic relatedness between some North American Amerindians (the Chipewyan and the Cheyenne) and certain populations of central/southern Siberia (particularly the Kets, Yakuts, Selkups, and Altays), at the resolution of major Y-chromosome haplogroups. This pattern agrees with the distribution of mtDNA haplogroup X, which is found in North America, is absent from eastern Siberia, but is present in the Altais of southern central Siberia.^[42]^[45]^[46]

Haplogroup C3b

For more details on this topic, see Haplogroup C3 (Y-DNA).

Spread of Haplogroup C3 in Indigenous populations.

Haplogroup C3 (M217, P44) is mainly found in indigenous Siberians, Mongolians and Oceanic populations. Haplogroup C3 is the most widespread and frequently occurring branch of the greater (Y-DNA) haplogroup C. Haplogroup C3 decedent C3b (P39) is commonly found in today's Na-Dené speakers with the highest frequency found among the Athabaskan's at 42%.^[37] This distinct and isolated branch C3b (P39) includes almost all the Haplogroup C3 Y-chromosomes found among all indigenous peoples of the Americas.^[47] The Na-Dené groups are also unusual among indigenous peoples of the Americas in having a relatively high frequency of Q-M242 (25%).^[35] This indicates that the Na-Dené migration occurred from the Russian Far East after the initial Paleo-Indian colonization, but prior to modern Inuit, Inupiat and Yupik expansions.^[9]^[10]^[13]

mtDNA

For more details on mtDNA in general, see Mitochondrial DNA.

Mitochondrial Eve is defined as the woman who was the matrilineal most recent common ancestor for all living humans. Mitochondrial Eve is generally estimated to have lived around 200,000 years ago most likely in East Africa, long before her male counterpart Y-chromosomal Adam.^[48] Mitochondrial Eve is the most recent common matrilineal ancestor, not the most recent common ancestor.^[49]^[50]

==================================

When studying human mitochondrial DNA (mtDNA) haplogroups, the results indicate that Indigenous Amerindian haplogroups, including haplogroup X, are part of a single founding east Asian population.^[51] It also indicates that the distribution of mtDNA haplogroups and the levels of sequence divergence among linguistically similar groups were the result of multiple preceding migrations from Bering Straits populations.^[27]^[52] All Indigenous Amerindian mtDNA can be traced back to five haplogroups, A, B, C, D and X.^[53] More specifically, Indigenous Amerindian mtDNA belongs to sub-haplogroups that are unique to the Americas and not found in Asia or Europe: A2, B2, C1, D1, and X2a (with minor groups C4c, D2, D3, and D4h3).^[52] This suggests that 95% of Indigenous Amerindian mtDNA is descended from a minimal genetic founding female population, comprising sub-haplogroups A2, B2, C1b, C1c, C1d, and D1.^[53] The remaining 5% is composed of the X2a, D2, D3, C4, and D4h3 sub-haplogroups.^[52]^[53]

X is one of the five mtDNA haplogroups found in Indigenous Amerindian peoples. Unlike the four main American mtDNA haplogroups (A, B, C and D), X is not at all strongly associated with east Asia.^[5] Haplogroup X genetic sequences diverged about 20,000 to 30,000 years ago to give two sub-groups, X1 and X2. X2's subclade X2a occurs only at a frequency of about 3% for the total current indigenous population of the Americas.^[5] However, X2a is a major mtDNA subclade in North America, where among the Algonquian peoples it comprises up to 25% of mtDNA types.^[3]^[54] It is also present in lower percentages to the west and south of this area — among the Sioux (15%), the Nuu-chah-nulth (11%–13%), the Navajo (7%), and the Yakama (5%).^[36] Haplogroup X is more strongly present in the Near East, the Caucasus, and Mediterranean Europe.^[36] The predominant theory for sub-haplogroup X2a's appearance in North America is migration along with A, B, C, and D mtDNA groups, from a source in the Altai Mountains of central Asia.^[45]^[46]^[55]^[56]

Sequencing of the mitochondrial genome from Paleo-Eskimo remains (3,500 years old) are distinct from modern Amerindians, falling within sub-haplogroup D2a1, a group observed among today's Aleutian Islanders, the Aleuts and Siberian Yupik populations.^[57] This suggests that the colonizers of the far north and subsequently Greenland originated from later coastal populations.^[57] Then a genetic exchange in the northern extremes introduced by the Thule people (proto-Inuit) approximately 800–1,000 years ago began.^[11]^[58] These final Pre-Columbian migrants introduced haplogroups A2a and A2b to the existing Paleo-Eskimo populations of Canada and Greenland, culminating in the modern Inuit.^[11]^[58]

AtDNA

For more details on autosomal DNA in general, see Human genetic variation .

Genetic diversity and population structure in the American landmass is also done using autosomal (atDNA) micro-satellite markers genotyped; sampled from North, Central, and South America and analyzed against similar data available from other indigenous populations worldwide.^[31]^[59] The Amerindian populations show a lower genetic diversity than populations from other continental regions.^[59] Observed is a decreasing genetic diversity as geographic distance from the Bering Strait occurs as well as a decreasing genetic similarity to Siberian populations from Alaska (the genetic entry point).^[31]^[59] Also observed is evidence of a higher level of diversity and lower level of population structure in western South America compared to eastern South America.^[31]^[59] There is a relative lack of differentiation between Mesoamerican and Andean populations, a scenario that implies that coastal routes were easier for migrating peoples (more genetic contributors) to traverse in comparison with inland routes.^[31] The over-all pattern that is emerging suggests that the Americas were recently colonized by a small number of individuals (effective size of about 70), which grew by a factor of 10 over 800 – 1000 years.^[5]^[60] The data also shows that there have been genetic exchanges between Asia, the Arctic and Greenland since the initial peopling of the Americas.^[60]^[61]

Overlaps between DNA types

Further information: Population genetics

Populations that have a specific combination of autosome, Y and MT-haplogroup mutations can generally be found with regional variations. Autosomes, Y mutations and mt mutations do not necessarily occur at a similar time and there are differential rates of sexual selection between the two sex chromosomes.^[62] This combined with population bottlenecks, the founder effect, mitochondrial mutations and genetic drift will alter the genetic composition of isolated populations, resulting in very distinguishable mutation patterns.^[63] (i.e. Taínos,^[64] Fuegians,^[65] Inuit,^[66] Yupik^[67] and Algonquian^[5])

The rough overlaps between Y-DNA and mtDNA between the Americas, Circumpolar north, and Siberian indigenous populations are:

Y-DNA haplogroup(s) -	mtDNA haplogroup(s) -	Geographical area(s)
Q, R1, C3	A, X, Y, C, D (M types), (N types	Russian far east, Americas, Arctic

Old world genetic admixture

For more details on genetic admixture in the Americas, see Miscegenation#Genetic studies of racial admixture.

Triangle plot shows average admixture of five North American ethnic groups. Individuals that self-identify with each group can be found at many locations on the map, but on average groups tend to cluster differently.^[68]

Interracial marriage and interracial sex, and more generally the process of racial admixture, has its origins in prehistory. Nonetheless, racial mixing became widespread during European colonialism in the Age of Discovery.^[69] Genetic exchange between two populations reduces the genetic distance between the populations and is measurable in DNA patterns.^[62] During the Age of Discovery, beginning in the late 1400s CE, European explorers sailed the oceans eventually reaching all the major continents.^[70] During this time Europeans contacted many populations, isolated for millennia.^[71] The genetic demographic composition of the Eastern Hemisphere has not changed significantly since the age of discovery. However, genetic demographics in the Western Hemisphere were radically altered by events following the voyages of Christopher Columbus.^[71] The European colonization of the Americas brought contact between Amerindian populations and the distant peoples of Europe, Africa and Asia. As a result the Americas today have significant and complex multiracial populations.^[71] Also, many individuals who self-identify as one race nonetheless exhibit genetic evidence of a multiracial ancestry.^[72]

The European invasion of Latin America was largely executed by male soldiers and sailors from Iberia, Spain and Portugal.^[73] Because unaccompanied by European women on their campaigns, the new soldier-settlers fathered children with Amerindian women and later with African slaves.^[74] These new children were generally identified by the Iberian colonists as Castas.^[75] In the 1600s CE, the North American fur trade brought more European men, from France and Great Britain, who bred with North Amerindian women.^[76] These offspring were identified as Métis or Bois-Brûlés by the French and mixed-bloods, half-breeds or Country-born by the English.^[77] From the second half of the 19th Century to the beginning of the 20th century large numbers of northern Europeans migrated to the Americas and consequently altered the Demographics of the Americas.^[78] Following World War II and subsequent world wide migrations, the current American populations' genetic admixture can be traced to all corners of the world.^[5]^[79]

Blood groups

Frequency of O group in indigenous populations. Note the predominance of this group in Indigenous Americans.

Further information: ABO blood group system

Prior to the 1952 confirmation of DNA as the hereditary material by Alfred Hershey and Martha Chase, scientists used blood proteins to study human genetic variation.^[80]^[81] The ABO blood group system is widely credited to have been discovered by the Austrian Karl Landsteiner, who found three different blood types in 1900.^[82] Blood groups are inherited from both parents. The ABO blood type is controlled by a single gene (the ABO gene) with three alleles: i, I^A, and I^B.^[83]

Research by Ludwik and Hanka Herschfeld during World War I found that the frequencies of blood groups A,B and O differed greatly from region to region.^[81] The "O" blood type (usually resulting from the absence of both A and B alleles) is very common around the world, with a rate of 63% in all human populations.^[84] Type "O" is the primary blood type among the indigenous populations of the Americas, in-particular within Central and South America populations, with a frequency of nearly 100%.^[84] In indigenous North American populations the frequency of type "A" ranges from 16% to 82%.^[84] This suggests again that the initial Amerindians evolved from an isolated population with a minimal number of individuals.^[85]^[86]

Distribution of ABO blood types
in various modern Indigenous Amerindian populations
Test results as of 2008^[87]
PEOPLE GROUP	O (%)	A (%)	B (%)	AB (%)
Blackfoot (N. Am. Indian)	17	82	0	1
Bororo (Brazil)	100	0	0	0
Eskimos (Alaska)	38	44	13	5
Inuit (Eastern Canada & Greenland)	54	36	23	8
Hawaiians	37	61	2	1
Indigenous North Americans (as a whole Native Nations/First Nations)	79	16	4	1
Mayas (modern)	98	1	1	1
Navajo	73	27	0	0
Peru	100	0	0	0

Genealogical test

Main article: Genealogical DNA test

A genealogical DNA test examines the nucleotides at specific locations on a person's DNA for genetic genealogy purposes.^[88] The test results are not meant to have any medical value; they are intended only to give genealogical information. Genealogical DNA tests generally involve comparing the results of living individuals to historic populations.^[88] The general procedure for taking a genealogical DNA test involves taking a painless cheek-scraping (also known as a buccal swab) at home and mailing the sample to a genetic genealogy laboratory for testing. The most popular ancestry tests are Y chromosome (Y-DNA) testing and mitochondrial DNA (mtDNA) testing which test direct-line paternal and maternal ancestry, respectively. DNA tests (autosomal DNA) for other purposes attempt, for example, to determine a person's comprehensive genetic make-up and/or ethnic origins. A man's patrilineal ancestry, or male-line ancestry, can be traced using the DNA on his Y chromosome (Y-DNA) through Y-STR testing. This is useful because the Y chromosome passes down almost unchanged from father to son. Results showing specific sub-Haplogroups of Q, R1 and C3b implies that he is, in whole or in-part, indigenous to the Americas.^[89] A person's matrilineal or mother-line ancestry can be traced using the DNA in his or her mitochondria, the mtDNA. This mtDNA is passed down by the mother unchanged, to all children. If one's mtDNA belonged to specific sub-Haplogroups of, A, B, C, D or X2a, the implication would be that he or she is, in whole or part, indigenous to the Americas.^[90]

Y Haplogroup Q

Root = Q M242 [Back to the roots]

P36.2, L232, L273.1, L274

Derived near Q-MEH2,Approx. hg: Q-M346,Q1a (ISOGG: Q1a,Q1a3,Q1a)

MEH2, L472, L528

Q1a1 (ISOGG: Q1a1,Q1a1) M120, N14, M265

Approx. hg: Q-M25,Q1a2 (ISOGG: Q1a2)

M25, M143, L714, L716

Approx. hg: Q-M25

L712

Approx. hg: Q-M25

L697.2, L713, L715, M365.3

Approx. hg: Q-M346,Q1a3,Approx. hg: Q-L56 (ISOGG: Q1a,Q1a3)

M346, L56, L57, L474, L892, L942

Q1a3a,Approx. hg: Q-L53*,Approx. hg: Q-M346 (ISOGG: Q1a3a,Q1a3a,Q1a3a)

L53, L55, L213, L331, L475, L476

Q1a3a

L54

Approx. hg: Q-M3,Q1a3a1 (ISOGG: Q1a3a1)

M3, L341.2

Q1a3a1a

M19

Q1a3a1b

M194

Q1a3a1c

M199, P106, P292

Approx. hg: Q1a3a

PAGES00104, PAGES00126

Approx. hg: Q1a3a

PAGES00131

Approx. hg: Q-M3

L663

Approx. hg: Q-M3

SA01

Approx. hg: Q-M3

L766, L767

Approx. hg: Q-M3

L883, L884, L885, L886, L887

Approx. hg: Q-M3

L888, L889, L890, L891

Q1a3a2

L191

Approx. hg: Q-L53* (ISOGG: Q1a3a3)

L330, L334

Approx. hg: Q-L53* (ISOGG: Q1a3a3a)

L329, L332, L333

Approx. hg: Q-L53

L400, L401

Approx. hg: Q-L53

L456

Approx. hg: Q-L53,Approx. hg: Q-L53 (ISOGG: Q1a3a4)

L568, L569, L570, L571

Approx. hg: Q-L569

L567

Approx. hg: Q-L569

L619.1

Approx. hg: Q-L53

L804, L805

Approx. hg: Q-L53

L807

Q1a3b M323

Approx. hg: Q-M346

L717, L718

Approx. Q-L56

L940

Approx. hg: Q-L527,Approx. hg: Q-M346 (ISOGG: Q1a3c)

L527, L529.1, L639

Approx. hg: Q-L56

L933, L938, L941

Approx. hg: Q-L56

L932, L934, L935, L936, L937, L939

Q1a4

P89.1

Approx. hg: Q-M378,Approx. hg: Q-L245(x,Approx. hg: Q-L245,Q1b (ISOGG: Q1b,Q1b)

L275, L314, L606, L612

Q1b (ISOGG: Q1b1)

M378, L214, L215

Q1b1 (ISOGG: Q1b1a)

L245

Q1b1a (ISOGG: Q1b1a1)

L272.1

Approx. hg: Q-L245*

L315

Approx. hg: Q-L245

L619.2

Approx. hg: Q-M378*

L301

Approx. hg: Q-M378

L327

=======================

Y-chromosomes of Native South Americans (Roewer et al. 2013)

It would be useful to sequence these South American C3* Y-chromosomes to see how they are related to the C3b-P39 found in some native North Americans as well as other unresolved C3* from Asia. It would also be worthwhile to look at autosomal data from these populations, to see if they are wholly descended from First Americans, or have evidence of more recent gene flow from East Asia.

PLoS Genet 9(4): e1003460. doi:10.1371/journal.pgen.1003460

Continent-Wide Decoupling of Y-Chromosomal Genetic Variation from Language and Geography in Native South Americans

Lutz Roewer et al.

Numerous studies of human populations in Europe and Asia have revealed a concordance between their extant genetic structure and the prevailing regional pattern of geography and language. For native South Americans, however, such evidence has been lacking so far. Therefore, we examined the relationship between Y-chromosomal genotype on the one hand, and male geographic origin and linguistic affiliation on the other, in the largest study of South American natives to date in terms of sampled individuals and populations. A total of 1,011 individuals, representing 50 tribal populations from 81 settlements, were genotyped for up to 17 short tandem repeat (STR) markers and 16 single nucleotide polymorphisms (Y-SNPs), the latter resolving phylogenetic lineages Q and C. Virtually no structure became apparent for the extant Y-chromosomal genetic variation of South American males that could sensibly be related to their inter-tribal geographic and linguistic relationships. This continent-wide decoupling is consistent with a rapid peopling of the continent followed by long periods of isolation in small groups. Furthermore, for the first time, we identified a distinct geographical cluster of Y-SNP lineages C-M217 (C3*) in South America. Such haplotypes are virtually absent from North and Central America, but occur at high frequency in Asia. Together with the locally confined Y-STR autocorrelation observed in our study as a whole, the available data therefore suggest a late introduction of C3* into South America no more than 6,000 years ago, perhaps via coastal or trans-Pacific routes. Extensive simulations revealed that the observed lack of haplogroup C3* among extant North and Central American natives is only compatible with low levels of migration between the ancestor populations of C3* carriers and non-carriers. In summary, our data highlight the fact that a pronounced correlation between genetic and geographic/cultural structure can only be expected under very specific conditions, most of which are likely not to have been met by the ancestors of native South Americans.

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Faces

Modern Faces give clues to Ancient Migration

The theories about how anatomically modern humans populated the world are hotly-debated. However, genetic and archaeological evidence points towards an initial migration from southwestern Africa over 100,000 years ago, which spread eastwards out of Africa into the Arabian Peninsula, before a small group began a worldwide dispersal around 60,000 years ago along mainly coastal routes. Do the faces of today’s indigenous people around the world still leave traces of these ancient migrations? During the Upper Palaeolithic humans may have looked quite different from their descendants today; nevertheless, a selection of modern male faces and their common Y-chromosome haplogroups provide a speculative look.

Africa to Europe

San Bushmen

A 2009 study on African genetics located the origin of modern human migration in south-western Africa, near the coastal border of Namibia and Angola. The site is the homeland of the indigenous San people. Studies show that the San carry some of the most divergent (oldest) Y-chromosome haplogroups, specific sub-groups of A and B, the two earliest branches on the human Y-chromosome tree, suggesting they may be descendents of a population ancestral to all modern humans.

Arab – image source: sunya.net
The departure of mankind from Africa involved them crossing the much lower waters of the Red Sea and moving along the green coastlines and interior of Arabia and on to the rest of Eurasia. Supercluster F appeared around 50,000 years ago and is the most common macro-haplogroup outside of Africa with more than 90% of the world’s population.

Anatolian

The DNA of modern Turkish people suggests that a human expansion occurred from 50,000 years ago in the Middle East, through Anatolia, and finally to the rest of Europe. There are many Y-DNA haplogroups present in Turkey; the majority are shared with European, Caucasian and Middle Eastern populations such as haplogroups E3b, G, J, I, R1a, R1b, K and T.

Balkan
In 2002, the oldest modern human remains in Europe were discovered in Romania. They are 30-40,000 years old and are likely to represent among the first people to have entered the continent. Haplogroup I is a Palaeolithic ‘indigenous European’ marker which originated around 20-25,000 years ago around the time of the Last Glacial Maximum. It arose in descendants of Haplogroup IJ men arriving from the Middle East; IJ is up to 40,000 years old, suggesting that IJ colonists formed the first wave into Europe and the now dominant Haplogroup R1 arrived later. The greatest density of Haplogoup I today is to be found in Bosnia (54%) and Herzegovina (71%).

Germanic
In 2007, evidence of the earliest human of occupation Germany was discovered in the form of a 35,000 year old figurine of a mammoth. By 25,000 years ago, the Last Glacial Maximum rendered much of Europe uninhabitable; people took refuge in Iberia, the Balkans, the Ukraine and Italy. As the glaciers receded from about 16,000 years ago, Europe began to be slowly repopulated. Haplogroup I appears to diverge from this point onwards and the re-colonisation of Northern Germany is marked by people bearing the I1 and I2b clades.

Scandinavian
The earliest traces of human occupation in Norway are found along the coast, where the huge ice shelf melted between 13,000 and 10,000 years ago. The oldest finds are stone tools dating from 10,500 years ago, with dwelling sites dating from about 7,000 years ago. Today Haplogroup I1 occurs at greatest frequency in Scandinavia.

Africa to Australia

San Bushmen

Arab - image source:
Archaeological evidence found in Yemen and Oman has raised the possibility that modern humans were established on the southern part of the Arabian Peninsula as far back as 125,000 years ago when the region was relatively lush and habitable and the Red Sea was shallow enough to be crossed on foot or on a small raft. However, genetic evidence suggests that the group who actually went on to people Eurasia came much later, around 60,000 years ago. They probably followed the same migration route around the coastlines from Africa along Yemen and the sea shores of Oman as climatic conditions dictated.

Virumandi Andithevar – Piramalai Kallar
Any archaeological remains of the coastal migration route around India to South East Asia and Australia are now probably under the sea. However, Virumandi Andithevar, of the Piramalai Kallar community from the Tamil Nadu region of southern India, was identified by the Genographic Project as one of the direct descendants of the first modern human settlers in India. His Y-DNA belongs to Haplogroup C and he carries the M130 marker which defines the first migrants to South East Asia and Australia from the African coast 60,000 years ago; more than half of Australian Aborigines also carry the M130 gene.

Vedda – image source:
Modern human remains dated to around 37,000 years ago have been found in Sri Lanka. Later remains from as early as 18,000 years ago suggest a direct line of descent to the indigenous Vedda population which inhabits the area today.

Jarawa – image source
The Andaman Islands are thought to be a key stepping stone in the coastal migration towards Southeast Asia, Japan and Australia. Males of the indigenous Onge and Jarawa tribes almost exclusively belong to Haplogroup D, which is also found in Tibet and Japan. However, this is a subclade which has not been seen outside of the Andamans and highlights the genetic isolation of these tribes, for longer than any known ancient population in the world. Their ancestors are thought to have arrived in the islands 55,000 years ago from coastal India as part of the first wave of modern human expansion out of Africa.

Orang Asli
The geographical position of the Malay Peninsula made it a main thoroughfare on the first wave of migration south. At that time, the much lower sea levels meant that most of maritime Southeast Asia was one land mass; it is known as the lost continent of Sunda. Archaeological evidence of modern human settlement in Peninsular Malaysia is at least 50,000 years old. The mitochondrial DNA (mtDNA) lineages of Malaysia’s indigenous Orang Asli (meaning ‘original men’ in Malay) tribes are also estimated to be around 50,000 years old.

Australian Aborigine
The oldest modern human remains found in Australia have been dated to around 45,000 years ago. Recent genetic studies suggest that Australia was populated by one single migration from Asia as opposed to several waves. Haplogroup C4 is at a high frequency among Australian Aborigines and it has not been found outside of that continent. The first settlers probably made their way southeast along the coast of Sunda until they reached the straits between Sunda and Sahul, the continental land mass that was made up of present-day Australia and New Guinea. They then made the final leg of the journey by sea. Australian Aborigines are the oldest continuous population outside of Africa, the people who have longest occupied their traditional territory, and are the direct descendants of those first explorers.

South East Asia to North America

Orang Rimba – image source: indonesianartandculture.com

While the ancestors of Australian Aborigines headed southeast along the coast of Sunda, others may have eventually turned northeast around 40,000 years ago. The prehistoric northward migration of Haplogroup C in mainland East Asia likely followed the coastline and is consistent with the northward migration of the East Asian Y-chromosome, Haplogroup D.

Ryukyuan – image source: blog.fmokinawa.co.jp

The earliest modern human bones found in Japan are around 32,000 years old. At this time Japan was connected to the continent through several land bridges, notably one linking the Ryukyu Islands to Taiwan and the Korean peninsula, and another one connecting to the Siberian mainland. The Philippines and Indonesia were also connected to the Asian mainland. This allowed migrations from China and Austronesia towards Japan. These first settlers in Japan were the ancestors of the indigenous Ryukyuans (Okinawans). Haplogroups C1 and D2 are unique to Japan and would most likely have come from Austronesia.

Ainu

The ancestors of the indigenous Ainu people settled in Hokkaido, the northernmost of Japan’s islands. Although the Ainu share many physical characteristics with modern Europeans, recent Y-DNA tests have not shown any genetic link. They belong mainly to Haplogroup D2; the only places outside of Japan in which Haplogroup D is common are Tibet and the Andaman Islands.

Itelmen –

The Itelmens are the indigenous inhabitants of the Kamchatka Peninsula in east Siberia, which began to be settled about 15,000 years ago. Haplogroup C3 predominates among the Itelmens and is believed to have originated approximately 20,000 years ago in eastern Asia. The Itelmens share their high frequency of C3 Y-DNA with other indigenous Siberian peoples around Kamchatka such as the Koryaks, Evens and Evenks. According to archaeological and genetic evidence, the low sea levels of the Ice Age allowed their ancient nomadic ancestors to traverse and inhabit the land bridge of Beringia that joined Siberia to Alaska for thousands of years, before the glaciers melted and Beringia finally disappeared beneath the sea around 10,000 years ago.

Tanana Athabascan –

This small human population survived the Last Glacial Maximum in isolation in Beringia before expanding to populate the Americas sometime after 16,500 years ago as the North American glaciers blocking the way southward melted. Beringia is believed to have supported two distinct migrations into the Americas. The first occurred with populations originating from the Chukotka Peninsula carrying Haplogroup Q1a3a1, which became predominant in indigenous Americans. The second featured minor groups carrying Haplogroup C3b originating from the Kamchatka Peninsula. The oldest existing archaeological site in the Bering region with traces of human occupation is in the Tanana River Valley, Alaska, which is approximately 13,000 years old. The Tanana people belong to the Athabascan group of indigenous North American Indians, and bear equally high frequencies of Haplogroups C3b and Q1a3a1.

Tlicho

Paleo-Indians began to move south and east into Canada; exact dates and routes are still hotly debated. The unglaciated areas of Canada at this time were along the Pacific coastline and east of the Rocky Mountains in the Alberta corridor. The Tlicho, formerly known as the Dogrib, are indigenous to the Northwest Territories in Canada and also hold a high frequency of Haplogroup C3b. This distinct and isolated clade includes almost all of the C3 Y-chromosomes found amongst indigenous peoples of the Americas as far south as Colombia and Venezuela.

Africa to South America

San Bushmen

Arab

The descendants of the small group of migrating modern humans who crossed from Africa into Arabia at the Red Sea gradually expanded and dispersed. The first main division in the expansion likely occurred on the Iranian coast of the Persian Gulf, with some groups continuing to move east while others remained in southern Iran between the Zagros Mountains and the sea.

Iranian

By 50,000 years ago the population that had remained in southern Iran began to expand: to the east into northern India; to the northwest to the Levant; and to the northeast to Central Asia. Because of its pivotal geographic position, Iran likely served as a major crossroads of human migration. This is reflected in the considerable Y-chromosome diversity found in Iranian males.

Niyazov Bey – Kazakh
By 40,000 years ago modern humans had spread to Central Asia following the grasslands resulting from the cooling climate. Niyazov Bey, a Kazakh Turk living in Kazakhstan, was identified by the Genographic Project as one of the direct descendants of the first modern human settlers in Central Asia. His Y-DNA belongs to Haplogroup P and he carries the M45 marker which defines the first migrants to Central Asia from Africa. Haplogroup P is the ancestoral Y-haplogroup of most Europeans and almost all of the indigenous peoples of the Americas; it also contains around one third to two thirds of the males among various populations of Central and Southern Asia.

Selkup
From Central Asia, modern humans headed northeast to populate Siberia. The precise antiquity of modern humans in this vast territory is still not known and archaeological evidence suggests that the settlement of Siberia was a complex and lengthy process. Haplogroup Q defines the route to Siberia; it is a branch of Haplogroup P and is believed to have arisen in Central Asia around 20,000 years ago. The highest frequency of Q in western Siberia today is found among the indigenous Selkup people (66%) who live in the far north. The Selkup language has many words of Iranian origin, indicating an ancient origin there.

Ket

The Ket are thought to be the only survivors of the first ancient nomadic people who originally lived throughout central Siberia. The highest frequencies of Haplogroup Q in Asia are found among the Kets (95%). Subclade Q1 is found mainly in Kets and Selkups in the north. Its age is estimated at 18,000 years old.

Chukchi –
The Chukchi are an indigenous people inhabiting the Chukotka Peninsula and the shores of the Chukchi Sea and the Bering Sea region of the Arctic Ocean. In his book The Journey of Man: A Genetic Odyssey, geneticist Spencer Wells shows how a small group of possibly no more than 20 of the Chukchi’s ancestors crossed the land bridge of Beringia sometime after 16,500 years ago. They were the first modern humans to migrate into the Americas and carried the subclade Q1a3a, which eventually became predominant in all indigenous North, Central and South Amerindians.

Eyak Athabascan –
The ancestors of the Athabascan people migrated across the Beringian land bridge into Alaska and northwest Canada. The unglaciated areas of Canada at this time were along the Pacific coastline and east of the Rocky Mountains in the Alberta corridor. Athabascan sub-families such as the Eyak, Tlingit, and Haida settled in the region and eventually spread farther east across Canada. The Y-DNA of the 10,300 year old remains of a human male found in Alaska was found to be in Haplogroup Q1a3a. Modern indigenous Athabascan popuations carry high frequencies of Q1a3a1.

Navajo –
The modern Navajo Nation occupies all of northeastern Arizona, the southeastern portion of Utah, and northwestern New Mexico and is the largest territory under Native American jurisdiction in the United States. Navajo people speak dialects of the Athabaskan language and are believed to have originated in northwestern Canada and eastern Alaska. The Navajo carry a very high frequency of Haplogroup Q1a3a1 (92%).

Nahua
While the first humans must have passed through Mexico at least 14,000 years ago archaeological evidence of human occupation of the region dates only to around 12,500 years ago. The indigenous Nahuas probably settled much later, originally coming from the deserts of northern Mexico and the southwestern U.S. and migrating into central Mexico in several waves. One migrating Nahua group, the Mexica, settled on an island in Lake Texcoco and became the dominant ethnic group of Mesoamerica. Ruling from their island capital of Tenochtitlan they formed the Aztec empire. The Nahua carry a very high frequency of Haplogroup Q1a3a1a (94%).

Chibcha
Archaeological evidence of continuous occupation of the lower Central American region dates to 11,000 years ago and there is a very likely ancestral link between the earliest Paleo Indians hunter-gatherers and the indigenous Chibcha-speaking peoples in the region. The Chibcha of Colombia seem to have evolved their culture in comparative isolation and carry a 100% frequency of Haplogroup Q1a3a1a.

Amazonian
The ancestors of the indigenous people of Brazil who settled in the Amazon rainforest probably entered the Amazon River basin from the northwest. The Amazonian Ticuna and Tupi people carry a 100% frequency of Haplogroup Q1a3a1a. The genetic marker M19, detected in 59% of Ticuna men, arose up to 10,000 years ago, suggesting that population isolation and perhaps even the establishment of tribal groups began soon after the initial colonisation of the region.

Tehuelche –
An archaeological site at Monte Verde in Patagonia, southern Chile, discovered evidence of human settlement dating back as far as 14,800 years ago; this suggests that the descending generations of the original Beringian Paleo-Indians in the far north had reached the southern end of South America in around 1,000 years. The Patagonian Paleo-Indians were nomadic hunter-gatherers who spent the winters in the lowlands and migrated during the summer to the central highlands of Patagonia and the Andes Mountains. Their descendants are the indigenous Tehuelche people.

Around 11,000 years ago the Selk’nam people started to split off from the ancestral Patagonian group. They became confined to Tierra del Fuego around 6,000 years ago, where they remained until their extinction in the 20th century. The boat- and sea-oriented Yámana and Kawésqar people were also indigenous to this region at the southern tip of South America, but their origins there are unclear.
The Yámana were completely indifferent to the bitter weather around Cape Horn; although they had fire and small shelters, they went about completely naked in the cold and biting wind of Tierra del Fuego, having physically adapted to the harsh climate. The modern population of full-blooded Yámana is down to its last member.
The Kawésqar were a nomadic seafaring people who spent most of their days in their canoes on the waterways of the Brecknock Peninsula. They were also adapted to the cold and rainy conditions and would travel in their canoes naked, oiled with whale blubber. The men sat at the front and hunted sea lions with spears, while the women paddled and the children maintained a continuous fire in a sand pit built in the middle of the canoe. At night they camped on beaches. Their descendants still live in the region, but the full-blooded ethnic lineage is down to its last 15 members.
The Yámana and Kawésqar were physically and culturally distinct from other Native Americans and one suggestion is that may be the descendants of sea-faring Australian Aborigines who colonised South America before the arrival of Amerindians. Geneticists seem divided on the issue. A team of Spanish geneticists in 2004 recovered ancient mtDNA from skeletal samples from Patagonia/Tierra del Fuego. Their analysis apparently revealed their DNA to be of Amerindian origin and linked to populations from Chile and Argentina, but different due to isolation right after their arrival at the southernmost extreme of South America. However, anthropologist George Weber believes that other mtDNA testing shows that they were not Amerindians but were the last surviving remnants of an earlier human migration into the Americas.
In 2009 genetic testing was undertaken on the modern Kawésqar community and on a recently discovered 150 year old mummified body of a Kawésqar Indian. MtDNA analysis showed that the modern Kawésqar were indeed the descendants of the original seafaring populations to inhabit the region. The Kawésqar mummy, however, was a straight match with the inland Aonikenk Indians, a now extinct group of Patagonian nomads. The mummy’s Y-DNA was “clearly Amerindian” (Haplogroup Q), while the modern Kawésqars’ Y-chromosome haplotypes were “unique and differed from the mummified body”; i.e. there was no direct kinship.
Until more conclusive DNA evidence is produced, does the face of a modern Kawésqar man give any clues about their origin?

Settlement of the Americas

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"Three maps of prehistoric America. (A) then gradual population expansion of the Amerind ancestors from their East Central Asian gene pool (blue arrow). (B) Proto-Amerind occupation of Beringia with little to no population growth for ≈20,000 years. (C) Rapid colonization of the New World by a founder group migrating southward through the ice-free, inland corridor between the eastern Laurentide and western Cordilleran Ice Sheets (green arrow) and/or along the Pacific coast (red arrow). In (B), the exposed seafloor is shown at its greatest extent during the last glacial maximum at ≈20–18 kya [25]. In (A) and (C), the exposed seafloor is depicted at ≈40 kya and ≈16 kya, when prehistoric sea levels were comparable. A scaled-down version of Beringia today (60% reduction of A–C) is presented in the lower left corner. This smaller map highlights the Bering Strait that has geographically separated the New World from Asia since ≈11–10 kya."

Maps depicting each phase of the three-step early human migrations for the peopling of the Americas.

There have been several models for the human settlement of America proposed by various academic communities. The question of how, when and why humans (Paleo-Indians) first entered the Americas 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, DNA analysis and linguistics. 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 America remains unclear.^[1]

In recent years researchers have sought to use familiar tools to validate or reject established theories such as Clovis first.^[2] 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 America 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.^[3]

Understanding the debate

The chronology of migration models is currently divided into two general approaches.^[4]^[5] 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.^[6]^[7] 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,^[8]^[9] with a much later mass secondary wave of immigrants.^[10]^[11]^[12]

One factor fueling the debate is the discontinuity of archaeological evidence between North and South America Paleo-Indian sites. A roughly uniform techno-complex pattern known as Clovis appears in North and Central American sites from at least 13,500 years ago onwards.^[13] 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 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)**^[14]
Dates BCE	Beringia "Land Bridge"	Coastal Route	Mackenzie Corridor
38,000-34,000	accessible (open)	open	closed
34,000-30,000	submerged (closed)	open	open
30,000-22,000	accessible (open)	closed	open
22,000-15,000	accessible (open)	open	closed
15,000 - today	submerged (closed)	open	open

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.^[15]^[16]^[17]^[18]^[19] 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.^[5]^[20] 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.^[5]

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 or by way of an interior passage (Mackenzie Corridor) along the eastern flank of the Rocky Mountains.^[18] When the Laurentide and Cordilleran ice sheets 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 glaciers hundreds of kilometers wide flowed down to the sea.^[16]

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.^[16]

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.^[12]

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, approximately 20,000 years ago,^[21] leaving evidence of occupation in specific localized areas. However, they would not be considered a founding population unless they had managed to migrate south, populate and survive the coldest part of the last ice age.^[22]

Timeline of selected archaeological, geological and genetic evidence

Further information: Archaeology of the Americas and Late Glacial Maximum

40,000 B.C. – 25,000 B.C. Paleolithic people move into Beringia across the Bering Land Bridge into western Alaska.^[10]^[23] Bison (buffalo), mammoths, and mastodons 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.^[24]
30,000–20,000 years ago: Mammoth bones, believed to have been chipped by humans, are found at the Yukon's Bluefish Caves^[25] sites investigated in the 1970s and 1980s by archeologist Jacques Cinq-Mars and his team.^[26] In 2004, Albert Goodyear of the South Carolina Institute of Archaeology and Anthropology announced radiocarbon dating of a bit of charcoal found in the Topper Site that preceded Clovis culture, near Allendale County, South Carolina.^[27] However, these deposits may have been made by forest fires.^[27] (Note: The dates given for the Old Crow and Topper digs have not been completely accepted by the archaeology community.)^[12]^[28] Ice-free corridor running north and south through Alberta and the continental glacier called Laurentide ice sheet. Introduced by geologists in the 1950s when stone tools were found in the Grimshaw, Bow River and in Lethbridge Alberta, under glacial sand and gravel; they are believed to be pre-glacial and may indicate nomadic humans occupied the area.^[29] A child's skull found in 1961 near Taber, Alberta is believed to be of one of the oldest inhabitants discovered in Alberta.^[30] (Note: The conclusions reached in Alberta on dates have not been accepted by the entire archaeology community.)^[31] Cambridge DNA Services estimates humans entered the Americas around 25,000 years ago.^[32] 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.^[11] Siberian mammoth hunters were believed to have penetrated far into the Arctic 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.^[16]
23,000–16,500 years ago: The Ice Age entombs the northern hemisphere in glaciers, cutting off routes from Siberia to the south.^[33] 2002 the presence of the X haplogroup 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.^[34] Genetic evidence (2007–2009) suggests the Beringia population's first genetic diversification from Asian populations occurred.^[35] An article in the American Journal of Human Genetics 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.^[11]^[35]^[36]
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.^[37] 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.^[5] Mass extinction of large fauna begins due to hunting and perhaps climate change. The dire wolf, Smilodon, Ameican lion, giant beaver, ground sloths, mammoths, American mastodon, American camel and American equine all become extinct by 11,000 years ago.^[38]^[39] Pre-Clovis sites uncovered from 1973 to 1978 Meadowcroft Rockshelter in Pennsylvania 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.^[40] pre-Clovis sites found in Monte Verde, located along Chinchihuapi Creek, in Chile. A crew of eighty people, led by Tom Dillehay of the University of Kentucky, excavated the site from 1977 to 1985.^[41] A coastal migration could explain how people arrived in Monte Verde.^[41] 2000, archaeologists say people were living at Cactus Hill, Virginia where stone tools and charcoal from a fire pit are found.^[42]
15,000–13,000 years ago: The Taima Taima mastodon kill/butchering site in Falcon, Venezuela 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 of the animal.^[43] Peñon woman found by an ancient lake bed near Mexico City in 1959.^[44] El Abra sites located in the valley east of the city of Zipaquirá, Colombia. 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.^[45] At Paisley Caves in the Cascade Range of Oregon, archaeologists find a scattering of human coprolites, or fossil feces in 2003.^[46] 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.^[46] These two genetic groups were the founding Paleo-Indians and later Na-Dené migration.^[17]^[47]
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 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.^[48] Clovis theory – People were living near Clovis, New Mexico 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.^[49] The Clovis culture was believed replaced by several more localized regional cultures, such as the Folsom tradition, from the time of the Younger Dryas cold climate period.^[11] Peru coastal region inhabitants fished with nets and bone hooks, collecting seafood such as crabs and sea urchins.^[50]
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.^[51] The Maritimes of Canada are settled by Paleo-Indians. Sites in and around Belmont, Nova Scotia have evidence indicating small seasonal hunting camps, perhaps re-visited over many generations.^[52] Luzia Woman's skull and other bones excavated in the Lagoa Santa, Brazil area by French archaeologist Annette Laming-Emperaire in the 1970s.^[53] By 2006, Lagoa Santa sites had produced no fewer than 75 well-preserved ancient skulls.^[53] 1994, University of California, Riverside anthropologist R. Erv Taylor examined seventeen of the Spirit Cave artifacts near Fallon, Nevada from the 1940s using mass spectrometry. The results indicated that a mummy was approximately 9,400–10,200 years old — older than any previously known North American mummy.^[54] 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.^[55]
9,000–8,000 years ago: Remains, known as Kennewick Man, are found in 1996 on the Columbia River near Kennewick, Washington. 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.^[56] A leaf-shaped projectile found on the body was long, broad and had serrated edges, all fitting the definition of a Cascade point. 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, Nicaragua and Costa Rica indicate that such sites almost certainly exist. Lack of funding for exploration in the areas has postponed likely finds.^[53] 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.^[57]

Genetics and blood type

For more details on this topic, see Genetic history of indigenous peoples of the Americas.

Schematic illustration of maternal (mtDNA) gene-flow in and out of Beringia.

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 to assert in 1973 (in The Ascent of Man) 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."^[58]

Modern Amerindian genetics studies focus primarily on Human Y-chromosome DNA haplogroups and Human mitochondrial DNA haplogroups. The genetic pattern emerging shows two very distinctive genetic episodes occurred, first with the initial peopling of the Americas, and secondly with European colonization of the Americas.^[5]^[59]^[60] The former is the determinant factor for the number of gene lineages, zygosity mutations and founding haplotypes present in today's indigenous Amerindian populations.^[59]

Genetics and blood studies indicate human settlement of the New World occurred in stages from the Bering sea coastline, with an initial layover on Beringia for the small founding population.^[5]^[17]^[22] 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.^[61] The Na-Dené, Inuit and Indigenous Alaskan populations exhibit haplogroup Q (Y-DNA) mutations, but are distinct from other indigenous Amerindians with various mtDNA and atDNA mutations.^[47]^[62]^[63] This suggests that the earliest migrants into the northern extremes of North America and Greenland derived from later migrant populations.^[64]^[65]

Land bridge theory

Shrinking of the Bering land bridge

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.^[66] This model of migration into the New World proposes that people migrated from Siberia into Alaska, tracking big game animal herds.

They were able to cross between the two continents by a land bridge called the Bering Land Bridge, which spanned what is now the Bering Strait, during the Wisconsin glaciation, the last major stage of the Pleistocene beginning 50,000 years ago and ending some 10,000 years ago, when ocean levels were 60 metres (200 ft) lower than today.

This information is gathered using oxygen isotope records from deep-sea cores. 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, 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 nomadic hunters were following game herds from Siberia across what is today the Bering Strait into Alaska, and then gradually spread southward. Based upon the distribution of Amerind languages and language families, a movement of tribes along the Rocky Mountain foothills and eastward across the Great Plains to the Atlantic seaboard is assumed to have occurred at least some 13,000 to 10,000 years ago.

Clovis culture

Further information: Clovis culture and Clovis point

Map showing the approximate location of the ice-free corridor and specific Paleoindian sites (Clovis theory).

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, 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).

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 in College Station and Thomas W. Stafford Jr., proprietor of a private-sector laboratory in Lafayette, Colorado 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 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, 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.^[67]

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.^[68] Another complication for the Clovis-only theory arose in 1997, when a panel of authorities inspected the Monte Verde site in Chile 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 turtles, shellfish, and tubers. This is a change of diet from the big game mammoths, long-horn bison, horse, and camels which early Clovis hunters apparently followed east into the New World.

At the Topper archaeological site (located along the banks of the Savannah River near Allendale, South Carolina) investigated by University of South Carolina archaeologist Dr. Albert Goodyear, charcoal material recovered in association with purported human artifacts returned radiocarbon dates of up to 50,000 years BP.

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.^[69]

Alternate Land Crossing Models

Crossings by foot of the Bering Sea are possible even without a land bridge by crossing the frozen sea.^[70]

Watercraft migration theories

Earlier finds have led to a pre-Clovis culture theory encompassing different migration models with an expanded chronology to supersede the "Clovis-first" theory.

Pacific coastal models

Main article: Coastal Migration

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 in southern Chile and Taima-Taima in western Venezuela. 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)^{[citation needed]} 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.^{[citation needed]}

Other coastal models, dealing specifically with the peopling of the Pacific Northwest 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 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 down the coasts of North and South America as far as Chile [2 62; 7 54, 57].

The Haida nation on the Queen Charlotte Islands off the coast of British Columbia 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 in Peru by 20,000 years ago and Monte Verde in 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 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 and Bruce Bradley champion the coastal Atlantic route. Their Solutrean Hypothesis is also based on evidence from the Clovis complex, but instead traces the origins of the Clovis toolmaking style to the Solutrean culture of Ice Age Western Europe.^[71] The theory suggests that early European people (or peoples) may have been among the earliest settlers of the Americas.^[72]^[73]

Citing evidence that the Solutrean culture of prehistoric Europe may have provided the basis for the tool-making of the Clovis culture in the Americas, the theory suggests that Ice Age Europeans migrated to North America by using skills similar to those possessed by the modern 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 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.^[74]^[75]

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.^[76]

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)^{[citation needed]}, but research has been limited in South America related to the possibility of early coastal migrations.

Y-haplogroup Q and Native American origins (Regueiro et al. 2013)

From the paper:

Table 2 provides coalescence time estimations based on 15 Y-STR loci for haplogroup Q-M242 and subhaplogroups Q1a3-M346, Q1a3a-L54 and Q1a3a1-M3. Due to the limitations and assumptions associated with the current calibrations of Y-STR mutation rates (Zhivotovsky et al., 2004; Goedbloed et al., 2009; Ravid-Amir and Rosset, 2010; Burgarella and Navascue/s, 2011), the dates generated in this study should only be taken as relative estimates. However, these relative values may be useful for comparisons among populations. Using the pedigree mutation rate (average mutation rate of 0.0025 per locus per generation; Goedbloed et al., 2009), we obtained coalescence estimates that were approximately three times younger than those calculated with the evolutionary rate (average mutation rate of 0.00069 per locus per generation; Zhivotovsky et al., 2004). In general, the genealogical estimates are more compatible with archeological data than the evolutionary rates

According to Table 2, the oldest TMRCA for M242 chromosomes is ~11ky using the pedigree rate and ~29ky using the evolutionary rate. In a previous post, I argued that in order to account for the fact that modern-day haplogroups have millions of modern representatives, a fairly high growth rate must be assumed for them, with one estimate of the effective rate being 0.84μ, where μ is the genealogical rate. Ergo, the ~11ky time estimate must be updated to something like ~13ky, which corresponds reasonably well -within the confidence limits- to the first colonization of the Americas.

The paper's conclusion:

Overall, our data are best explained by invoking a single major pre-Holocene migration that proceeded eastward in a trans-continental trek across Beringia and then southward to transverse the length of Americas-a scenario that fits nicely with the South Altaian origin of Native Americans as proposed by Dulik et al. (2012). The subsequent winnowing of the Native American gene pool via repeated founder effects and bottleneck events could have produced the Y chromosome distribution illustrated on the pie map (Fig. 2). The Q haplogroup frequency pattern of the Native Americans features: 1) a dramatic reduction of the ancestral L54 and MEH2 lineages of Central Asia and/or northeast Siberia and 2) a concomitant increase in the derived M3 state, which exerts total domination of the Q landscape in nearly all of South American reference populations examined. We also see evidence of a dramatic Mesoamerican postmigration population growth in the ubiquitous and diverse Y-STR profiles of the Mayan and other Mesoamerican populations in the PCA (Fig. 4), and the M242 and M3 networks (Fig. 5A,D). In the case of the Mayans, this demographic population growth was most likely fueled by the agricultural- and trade-based subsistence adopted during the pre-Classic age of their empire. Our results indicate that the oldest dates for Q-M242 are found in Northeast Siberia followed by populations from Mesoamerica, which is most likely a consequence of demographic expansion as discussed above. The diversity levels observed in the Altaian and Tuvinian regions of Central Asia, the lowest of all populations examined may be the consequence of bottleneck events fostered by the spatial isolation and low effective population size characteristic of a nomadic lifestyle.

It seems likely that the migration of Q-M242 descendants corresponds mainly to the "First Americans" sensu Reich et al. (2012) which makes up the bulk of Amerindian Y-chromosomes. Interestingly:

The recently sequenced genome of a Paleo-Eskimo _ 4,000 years old, belonging to the Saqqaq culture, provides evidence for a more recent migration from Siberia into the New World some 5.5 kya, independent of the pre-Holocene penetration that gave rise to the modern Native Americans and Inuit (Rasmussen et al., 2010). In addition, the Paleo-Eskimo individual is a member of the haplogroup Q1a*-MEH2 suggesting that this lineage likely traces a population migration originating in Northeast Siberia across the Bering Strait (Rasmussen et al., 2010).

and:

In the MDS plot, we observe a segregation between Eskimo populations from northeast Siberia and the Native American populations, differentiation likely due to the northeast Siberian presence of the MEH2 mutation which defines the Q1a* haplogroup.

So, it would appear that the additional "Eskimo" wave may be discernible within Q itself; the third "Na-Dene" wave cannot be distinguished on the basis of Q alone, and probably reflects the later entry of haplogroup C.

Am J Phys Anthropol DOI: 10.1002/ajpa.22207

On the Origins, Rapid Expansion and Genetic Diversity of Native Americans From Hunting-Gatherers to Agriculturalists

Maria Regueiro et al.

Given the importance of Y-chromosome haplogroup Q to better understand the source populations of contemporary Native Americans, we studied 8 biallelic and 17 microsatellite polymorphisms on the background of 128 Q Y-chromosomes from geographically targeted populations. The populations examined in this study include three from the Tuva Republic in Central Asia (Bai-Tai, Kungurtug, and Toora-Hem, n = 146), two from the northeastern tip of Siberia (New Chaplino and Chukchi, n = 32), and two from Mesoamerica (Mayans from Yucatan, Mexico n = 72, and Mayans from the Guatemalan Highlands, n = 43). We also see evidence of a dramatic Mesoamerican post-migration population growth in the ubiquitous and diverse Y-STR profiles of the Mayan and other Mesoamerican populations. In the case of the Mayans, this demographic growth was most likely fueled by the agricultural- and trade-based subsistence adopted during the Pre-Classic, Classic and Post-Classic periods of their empire. The limited diversity levels observed in the Altaian and Tuvinian regions of Central Asia, the lowest of all populations examined, may be the consequence of bottleneck events fostered by the spatial isolation and low effective population size characteristic of a nomadic lifestyle. Furthermore, our data illustrate how a sociocultural characteristic such as mode of subsistence may be of impact on the genetic structure of populations. We analyzed our genetic data using Multidimensional Scaling Analysis of populations, Principal Component Analysis of individuals, Median-joining networks of M242, M346, L54, and M3 individuals, age estimations based on microsatellite variation utilizing genealogical and evolutionary mutation rates/generation times and estimation of Y- STR average gene diversity indices.

6 comments:

Marnie said...

Table 1. Geographic localization and linguistic affiliation of the Native South American populations used to search for new Y SNPs
Population	n	Country	Geographic coordinates	Language (Language family)
South America
Arequipa	19	Peru	71°32′W; 16^o23′S	Quechua (Quechua)
Coyaima	13	Colombia	74°05′W; 03°50′N	Coyaima (Carib)
San Martin de Pangoa	33	Peru	74°29′W; 11^o25′S	Quechua (Quechua) and Nomatsiguenga (Arawak)
Tayacaja	33	Peru	74°34′W; 12°24′S	Quechua (Quechua)

Table 2. Microsatellite haplotypes for 16 individuals showing the derived allele for the SA01 marker
Codesa	Y microsatellite haplotypes															# Individuals
Codesa	19	389ab	389bb	390	391	392	393	437	438	439	448	456	458	635	GATA H4	# Individuals
a Codes for haplotypes found in South American populations: JMK, Janko Marka, Bolivia (n = 1); AMT, Amantani, Peru (n = 1); CHG, Chogo, Peru (n = 6); SMP, San Martín de Pangoa, Peru (n = 1); CUS, Cusco, Peru (n = 1); ANC, Ancahuasi, Peru (n = 1); TAY, Tayacaja, Peru (n = 2); MUS, Musucancha, Peru (n = 2); POC, Puerto Ocopa, Peru (n = 1). See Figure 2 for sample locations. b DYS389a-b: Allele designations according to Tarazona-Santos et al. (2001).
JMK01	13	13	17	21	10	14	13	14	11	12	22	14	16	22	11	1
AMT01	13	13	18	20	10	14	13	14	11	12	21	14	17	22	11	1
CHG01	13	13	18	21	10	15	13	14	11	13	21	14	17	22	11	1
CHG02	13	14	17	21	10	15	13	14	11	13	22	14	17	22	11	2
CHG03	13	14	18	21	10	14	13	14	11	12	21	15	17	22	11	1
CHG04	13	14	18	21	10	14	13	14	11	13	21	15	17	22	11	2
SMP01	13	14	17	21	10	14	13	14	11	13	21	14	17	22	11	1
CUS01	13	14	17	22	10	14	13	14	11	13	21	14	17	22	11	1
ANC01	13	14	18	21	10	14	13	14	11	12	22	14	16	22	11	1
MUS01	13	14	19	21	10	14	13	14	11	13	21	14	17	22	12	2
TAY01	13	14	18	21	10	14	13	14	11	13	21	15	18	22	11	1
TAY02	14	14	19	21	10	14	13	14	11	13	21	14	18	22	11	1
POC01	13	14	18	21	10	14	13	14	11	13	21	14	17	22	11	1

lunes, 25 de abril de 2016

Overview

Y-DNA

Haplogroup Q

Q subclades Q1a3a and Q1a3a1a

Haplogroup R1

Haplogroup C3b

mtDNA

AtDNA

Overlaps between DNA types

Old world genetic admixture

Blood groups

Genealogical test

See also

MATERIALS AND METHODS

Samples

Y-chromosome genotyping

Y-chromosome SNP search using DNA sequencing

Analytical methods

RESULTS

DISCUSSION AND CONCLUSION

Y-chromosomes of Native South Americans (Roewer et al. 2013)

Cusco

Mi gente

My people