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Anzick-1

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Anzick-1 is the name given to the skeletal remains of Paleo-Indian male infant found in Western Montana in 1968 that date to 12,707-12,556 years BP.[1] Anzick-1 is the only human that has been discovered from the Clovis Complex, and is the first ancient Native American genome to be fully sequenced.[2]

Paleogenomic analysis of the remains revealed Siberian ancestry and a close genetic relationship to modern Native Americans.[1][2] These findings support the hypothesis that modern Native Americans are descended from Asian populations who crossed Beringia between 32,000 and 18,000 years ago, and discredits the Solutrean Hypothesis.[1][2]

Anzick-1's discovery and subsequent analysis is controversial because although the researchers did not violate the Native American Graves Protection and Repatriation Act (NAGPRA), many Montana tribal members believe they should have been consulted before the analysis of the infant's skeleton and genome.[3]

Discovery

The Anzick site was accidentally discovered by a construction worker in a collapsed rock shelter near Wilsal, Montana.[4][5]

The Anzick-1 remains were found buried under numerous tools, 100 stone tools and 15 remnants of tools made of bone.[citation needed] The site contained hundreds of of stone projectile points, blades, and bifaces as well as two juveniles[5] Some of the artifacts were covered in red ochre.[5] The stone points were identified as part of the Clovis Complex because of their distinct shape and size.[4] Originally, the two human skeletons were both thought to contemporaneous with the Clovis Complex stone points, but later carbon dating revealed that only one of the human skeletons, Anzick-1, was from the Clovis period.[4] Anzick-1 predates the other skeleton by two millennia.[4]

Paleogenetic Findings

Once found and cataloged all these remains, different DNA analysis on one of the fragments of the child's bones were made. These analyzes revealed that the individual was closely related to Native Americans in Central and South America, instead of being closely related to the people of the Canadian Arctic, as had been thought until now, supporting the theory of multiple waves of colonization. For more than 20 years anthropologists have debated whether the first settlers who came to the New World did passing the Bering Strait, or sea from the southwest of Europe. This new analysis of the remains of Anzick-1 challenge the assumption that the first wave of migration away from Europe, because for the first time, has determined the complete genome sequence, and DNA, report on the linkages between today's Native Americans with the ancient inhabitants of East Asia that created that were the first settlers of the new continent. This study published in the journal Nature totally rule the European hypothesis and the idea that the early American settlers arrived millennia earlier than thought through from Bering takes hold. DNA analysis (analysis of mtDNA and the Y chromosome) show that the child belonged to a group of human beings which could be a direct ancestor of up to 80 percent of current Native American tribes. So the most likely scenario is that humans arrived in eastern Siberia Bering 26000–18000 years ago. 17,000 years ago, the glaciers recede allows them to cross the Bering Strait where some migrated to the Pacific coast, reaching Monte Verde in Chile by 14,600 years ago, while others - including the ancestors of Anzick-1 - headed interior of North America. Genetic analysis also revealed that the child is less closely related to Native North Americans America with the center and south, as the Maya of Central America and the Karitiana Brazilian natives. This can be explained better, scientists say, if we consider Anzick-1 as an individual belonging to a population that directly ancestral tribes of South America.

Nuclear DNA Analysis

Human nuclear DNA is located inside the nucleus of every cell and makes up the human genome.[6] Humans inherit half of their nuclear DNA from their mother and half from their father.[6] Throughout human evolution, mutations occur that are inherited in each subsequent generation.[6] Different populations have different frequencies of these mutations, and population histories can be ascertained from these mutations by comparing the mutations of one individual to other genomes from specific ethnic groups.[6] The genome of Anzick-1 was sequenced and analyzed to look for specific mutations that might point shed light on the population history of modern Native Americans.[1] Anzick-1's genome was compared to over 50 Native American genomes for comparison, and researchers found that it was significantly more similar to these Native American genomes than to any modern Eurasian population.[1] Interestingly, however Anzick-1's genome was closer to 44 Native American populations from Central and South America than with 7 Native American populations from North America.[1]

Analysis of mitochondrial DNA

The mitochondrial DNA analysis of the remains found, said Anzick-1 belonged to what is known as haplogroup or lineage D4h3a. This finding is important because D4h3a line is considered to be a lineage "founder", which belongs to the first people to reach Americas. Although it is rare in most of today's Native Americans in the US and Canada, D4h3a genes are more common in native people of South America, away from Montana cliff below which Anzick-1 was buried. This suggests a greater genetic complexity among Native Americans than previously thought, including an early divergence in the genetic lineage 13,000 years ago. One theory suggested that after crossing into North America from Siberia, a group of the first Americans, with the lineage D4h3a, moved south along the Pacific coast and finally through thousands of years, Central and South America; and others may have moved inland, east of the Rocky Mountains.[1]

Implications

Anzick-1's mtDNA, nuclear DNA, and Y-Chromosome analysis revealed a close genetic affinity to modern Native Americans and provided evidence of gene flow from Siberia into the Americas.[1] Some researchers believe that these findings support the Beringia Hypothesis of the peopling of the Americas and refute the Solutrean Hypothesis.[1] However, other researchers believe that these results could support the Solutrean Hypothesis of the peopling of the Americas.[7]

Beringia Hypothesis

The Beringia Hypothesis is a model for the peopling of the Americas that posits a migration of early Amerindians from Siberia across a land bridge that spanned the Bering Strait.[8] This hypothesis is supported by genetic and archaeological evidence that places the migration no earlier than 32 thousand years ago.[9] Ancient Native Americans could have entered the New World through an ice free corridor across the Beringian land bridge or they could have used boats to sail along the coast of Siberia, the Beringia land bridge, and North America.[6] The Anzick-1 paleogenetic analysis lends support to the Beringia Hypothesis theory and supports the idea that there were three waves of migration from ancient Siberia into the New World.[2]

Solutrean Hypothesis

The Solutrean hypothesis posits that modern Native Americans migrated to the New World across the Atlantic Ocean from Europe via "ocean current highways."[10][8][11] Some mtDNA evidence supports this hypothesis because haplogroup X, found in some Native American communities in northeastern North America, originated in Europe where the Solultrean culture developed.[8][10] Proponents of the Solutrean Hypothesis believe that ancient people crossed the Atlantic Ocean during a climatic event that raised glacier levels to a maxima that created a land bridge between Europe and North America.[10][8] These early migrants to the New World left evidence of their presence through cave paintings and a distinct tool culture that influenced the Clovis Complex tools.[8][7] Proponents of the Solutrean Hypothesis, like Kyle Bristow who wrote White Apocalypse, believe that Europeans migrated to the New World before ancient Native Americans crossed the Bering Strait.[12]

References

  1. ^ a b c d e f g h i Rasmussen, Morten; et al. (February 13, 2014). "The genome of a Late Pleistocene human from a Clovis burial site in western Montana". Nature. doi:10.1038/nature13025. Retrieved March 21, 2015. {{cite journal}}: Explicit use of et al. in: |first= (help)
  2. ^ a b c d Raff, Jennifer; Bolnick, Deborah (February 13, 2014). "Palaeogenomics: Genetic roots of the first Americans". Nature. doi:10.1038/506162a. Retrieved March 21, 2015.
  3. ^ Callaway, Ewen (February 12, 2014). "Ancient genome stirs ethics debate". Nature. doi:10.1038/506142a. Retrieved March 21, 2015.
  4. ^ a b c d Owsley, Douglas W; Hunt, David (May 2001). "Clovis and early Archaic crania from the Anzick site (24PA506), Park County, Montana". Plains Anthropologist. Retrieved March 22, 2015.
  5. ^ a b c Lahren, Larry; Bonnichsen, Robson (October 11, 1974). "Bone Foreshafts from a Clovis Burial in Southwest Montana". Science. Retrieved March 22, 2015.
  6. ^ a b c d e Jobling, Mark; et al. (2013). Human Evolutionary Genetics. Garland Science. ISBN 0815341482. {{cite book}}: Explicit use of et al. in: |first= (help)
  7. ^ a b Oppenheimer, Stephen; et al. (October 31, 2014). "Solutrean hypothesis: genetics, the mammoth in the room". World Archaeology. doi:10.1080/00438243.2014.966273. Retrieved March 22, 2015. {{cite journal}}: Explicit use of et al. in: |first= (help)
  8. ^ a b c d e Peterson, Barbara Bennett (2011). Peopling of the Americas : Currents, Canoes, and DNA. New York: Nova Science Publishers.
  9. ^ Jobling, Mark; et al. (2013). Human Evolutionary Genetics. Garland Science. ISBN ISBN 0815341482. {{cite book}}: Check |isbn= value: invalid character (help); Explicit use of et al. in: |first= (help)
  10. ^ a b c Stanford, Dennis J.; Bradley, Bruce A. (2012). Across Atlantic ice : the origin of America's Clovis culture. Berkeley, CA: University of California Press. ISBN 9780520227835.
  11. ^ Stanford, Dennis; Bradley, Bruce (2004). "The North Atlantic ice-edge corridor: a possible Paleolithic route to the new world". World Archaeology.
  12. ^ Bristow, Kyle (2010). White Apocalypse. CreateSpace Independent Publishing Platform. ISBN 1453768475.
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