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Added the the Solutrean Hypothesis sub-section.
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Expanded sections from the osteological and paleogenetic findings sections
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== Osteological Findings ==
== Osteological Findings ==

=== Overview ===
Anzick-1's skeletal remains included 28 cranial fragments, the left clavicle, and several ribs.<ref name=":2" /> These bones were discovered in highly fragmented states; however, partial reconstruction of the crania allowed for [[Bioarchaeology|age estimation]], investigation of basic health indicators, and some information about cultural practices. Originally, investigators thought the left clavicle showed evidence of cremation, but further analysis revealed that the discoloration was the result of groundwater staining and not fire.<ref name=":2" /> Additionally, all of the Anzick-1 remains were stained with ocher, which masks the natural color of the infant's bones.<ref name=":2" />
Anzick-1's skeletal remains included 28 cranial fragments, the left clavicle, and several ribs.<ref name=":2" /> These bones were discovered in highly fragmented states; however, partial reconstruction of the crania allowed for [[Bioarchaeology|age estimation]], investigation of basic health indicators, and some information about cultural practices. Originally, investigators thought the left clavicle showed evidence of cremation, but further analysis revealed that the discoloration was the result of groundwater staining and not fire.<ref name=":2" /> Additionally, all of the Anzick-1 remains were stained with ocher, which masks the natural color of the infant's bones.<ref name=":2" />


=== Age estimation, health status, and cultural modifications ===
=== Age estimation ===
Cranial bones fuse together along suture lines throughout the life of every human, and can be used to estimate the age at death of human remains.<ref name=":4">{{Cite book|title = Standards for Data Collection from Human Skeletal Remains: Proceedings of a Seminar at the Field Museum of Natural History|last = Buikstra|first = Jane E.|publisher = Arkansas Archaeological Report Research Series|year = 1994|isbn = 978-1563490750|location = |pages = |last2 = Ubelaker|first2 = Douglas H.}}</ref> The size and [[Suture (joint)|suture closure]] of Anzick-1's crania revealed that the individual was 1-2 years old.<ref name=":2" />
The age at death of an individual can be determined from several skeletal markers including cranial suture closure, tooth eruption rates, rates of epiphyseal fusion on long bones, and others.<ref name=":4" /> Cranial bones fuse together along suture lines throughout the life of every human, and can be used to estimate the age at death of human remains.<ref name=":4">{{Cite book|title = Standards for Data Collection from Human Skeletal Remains: Proceedings of a Seminar at the Field Museum of Natural History|last = Buikstra|first = Jane E.|publisher = Arkansas Archaeological Report Research Series|year = 1994|isbn = 978-1563490750|location = |pages = |last2 = Ubelaker|first2 = Douglas H.}}</ref> The small size and lack of [[Suture (joint)|suture closure]] of Anzick-1's crania revealed that the individual was 1-2 years old.<ref name=":2" /> The [[metopic suture]] is also present in the frontal bone of Anzick-1. This suture is present in most human infants but closes well before adulthood. The presence of a frontal suture in Anzick-1's remains corroborates the age estimation of 1-2 years old.


=== Skeletal markers of health ===
<nowiki> </nowiki>The cranial bones can also be useful for detecting evidence of physiological perturbations.<ref name=":4" /> For example, porosity on the frontal, parietal, and occipital bones can be an indicator of a nutritional deficiency that leads to [[anemia]].<ref>{{Cite journal|url = https://blackboard.vanderbilt.edu/bbcswebdav/pid-582674-dt-content-rid-1373402_1/courses/2015.01.SPR.AS.ANTH.274.01/Walker_etal_CausesOfPH_CribraOrbitaliaReappraisal_AJPA.pdf|title = The Causes of Porotic Hyperostosis and Cribra Orbitalia: A Reappraisal of the Iron-Deficiency-Anemia Hypothesis|last = Walker|first = Phillip L.|date = 2009|journal = American Journal of Physical Anthropology|doi = 10.1002/ajpa.21031|pmid = |access-date = March 24, 2015}}</ref> The reconstructed frontal, parietal, and occipital bone fragments of Anzick-1 showed no evidence of cribra orbitalia or [[porotic hyperostosis]].<ref name=":2" />
Cranial bones can also be useful for detecting evidence of physiological perturbations.<ref name=":4" /> Porotic hyperostosis is characterized by porous lesions on the parietal, occipital, and sometimes frontal bones.<ref name=":7">{{Cite book|title = The Cambridge Encyclopedia of Human Paleopathology|last = Aufderheide|first = Arthur C.|publisher = Cambridge University Press|year = 2006|isbn = |location = Cambridge, United Kingdom|pages = |last2 = Rodriguez-Martin|first2 = Conrado}}</ref> Cribra orbitalia is another pathological skeletal lesion that manifests as porosity on the orbital roof.<ref name=":7" /> Both porotic hyperostosis and cribra orbitalia are indicators of a nutritional deficiency that leads to [[anemia]].<ref>{{Cite journal|url = https://blackboard.vanderbilt.edu/bbcswebdav/pid-582674-dt-content-rid-1373402_1/courses/2015.01.SPR.AS.ANTH.274.01/Walker_etal_CausesOfPH_CribraOrbitaliaReappraisal_AJPA.pdf|title = The Causes of Porotic Hyperostosis and Cribra Orbitalia: A Reappraisal of the Iron-Deficiency-Anemia Hypothesis|last = Walker|first = Phillip L.|date = 2009|journal = American Journal of Physical Anthropology|doi = 10.1002/ajpa.21031|pmid = |access-date = March 24, 2015}}</ref> The reconstructed frontal, parietal, and occipital bone fragments of Anzick-1 were analyzed for these indicators of health; however, the crania showed no evidence of cribra orbitalia or [[porotic hyperostosis]].<ref name=":2" />


=== Cranial Vault Modification ===
<nowiki> </nowiki>Many cultures use wrappings and boards to manipulate the malleable cranial bones of infants into different shapes which may hold cultural significance.<ref name=":5">{{Cite journal|url = |title = Cranial Vault Modification and Ethnicity in Middle Horizon San Pedro de Atacama, Chile|last = Torres Rouff|first = Christina|date = Feburary 2002|journal = Current Anthropology|doi = 10.1086/338290|pmid = |access-date = }}</ref> This practice has been recorded in several different bioarchaeological contexts throughout the Americas.<ref name=":5" /> The shape of the cranial vault revealed no evidence of cultural [[Artificial cranial deformation|cranial vault modification]].<ref name=":2" />
Many cultures use wrappings and boards to manipulate the malleable cranial bones of infants into different shapes which may hold cultural significance.<ref name=":5">{{Cite journal|url = |title = Cranial Vault Modification and Ethnicity in Middle Horizon San Pedro de Atacama, Chile|last = Torres Rouff|first = Christina|date = Feburary 2002|journal = Current Anthropology|doi = 10.1086/338290|pmid = |access-date = }}</ref> This practice has been recorded in several different bioarchaeological contexts throughout the Americas.<ref name=":5" /> The shape of Anzick-1's cranial vault revealed no evidence of cultural [[Artificial cranial deformation|cranial vault modification]].<ref name=":2" />


== Paleogenetic Findings ==
== Paleogenetic Findings ==
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=== Nuclear DNA Analysis ===
=== Nuclear DNA Analysis ===
Human nuclear DNA is located inside the nucleus of every cell and makes up the human genome.<ref name=":8">{{Cite book|title = Human Evolutionary Genetics|last = Jobling|first = Mark et al.|publisher = Garland Science|year = 2013|isbn = 0815341482|location = |pages = }}</ref> Humans inherit half of their nuclear DNA from their mother and half from their father.<ref name=":8" /> Throughout human evolution, mutations occur that are inherited in each subsequent generation.<ref name=":8" /> 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.<ref name=":8" /> 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.<ref name=":0" /> 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.<ref name=":0" /> 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.<ref name=":0" />
Human nuclear DNA is located inside the nucleus of every cell and makes up the human genome. Humans inherit half of their nuclear DNA from their mother and half from their father.


=== Y-Chromosome Analysis ===
=== Y-Chromosome Analysis ===
The y-chromosome is inherited from father to son in each generation. Because males have an x-chromosome and a y-chromosome, and females have two x-chromosomes, the y-chromosome can only be inherited from an male's father. Specific mutations on the y-chromosome can be used to trace the paternal lineage of a male individual.<ref name=":8" /> Like mtDNA, these mutations can be grouped and categorized into haplogroups. The y-chromosome of Anzick-1was sequenced and researchers determined that his y-chromosome haplogroup is Q-L54*(xM3), one of the major founding lineages of the Americas.<ref name=":0" />


== Implications ==
== Implications ==

Revision as of 22:41, 29 March 2015

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 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]

Osteological Findings

Anzick-1's skeletal remains included 28 cranial fragments, the left clavicle, and several ribs.[4] These bones were discovered in highly fragmented states; however, partial reconstruction of the crania allowed for age estimation, investigation of basic health indicators, and some information about cultural practices. Originally, investigators thought the left clavicle showed evidence of cremation, but further analysis revealed that the discoloration was the result of groundwater staining and not fire.[4] Additionally, all of the Anzick-1 remains were stained with ocher, which masks the natural color of the infant's bones.[4]

Age estimation

The age at death of an individual can be determined from several skeletal markers including cranial suture closure, tooth eruption rates, rates of epiphyseal fusion on long bones, and others.[6] Cranial bones fuse together along suture lines throughout the life of every human, and can be used to estimate the age at death of human remains.[6] The small size and lack of suture closure of Anzick-1's crania revealed that the individual was 1-2 years old.[4] The metopic suture is also present in the frontal bone of Anzick-1. This suture is present in most human infants but closes well before adulthood. The presence of a frontal suture in Anzick-1's remains corroborates the age estimation of 1-2 years old.

Skeletal markers of health

Cranial bones can also be useful for detecting evidence of physiological perturbations.[6] Porotic hyperostosis is characterized by porous lesions on the parietal, occipital, and sometimes frontal bones.[7] Cribra orbitalia is another pathological skeletal lesion that manifests as porosity on the orbital roof.[7] Both porotic hyperostosis and cribra orbitalia are indicators of a nutritional deficiency that leads to anemia.[8] The reconstructed frontal, parietal, and occipital bone fragments of Anzick-1 were analyzed for these indicators of health; however, the crania showed no evidence of cribra orbitalia or porotic hyperostosis.[4]

Cranial Vault Modification

Many cultures use wrappings and boards to manipulate the malleable cranial bones of infants into different shapes which may hold cultural significance.[9] This practice has been recorded in several different bioarchaeological contexts throughout the Americas.[9] The shape of Anzick-1's cranial vault revealed no evidence of cultural cranial vault modification.[4]

Paleogenetic Findings

A team of researchers throughout the United States and Europe conducted paleogenetic research on the Anzick-1 skeletal remains. They sequenced the mitochondrial DNA (mtDNA), the full nuclear DNA, and the Y-chromosome, and compared these sequences to those of modern populations throughout the world.[1] The results of these analyses allowed the researchers to make conclusions about ancient migration patterns and the peopling of the Americas.

Mitochondrial DNA Analysis

MtDNA is DNA located in mitochondria, an organelle that is found in human cells. The mitochondria is maternally inherited and analysis of the mtDNA can provide information about maternal ancestry.[10] MtDNA genomes are classified into different haplogroups based on a shared common ancestor, and distinct haplogroups provide information about ancient migration patterns.[11] Morten Rasumssen and Sarah L. Anzick et al. sequenced the mitochondrial DNA of Anzick-1 and determined that the infant represents an ancient migration to North America from Siberia. They found that Anzick-1's mtDNA belongs to the haplogroup D4h3a, a "founder" haplogroup that might represent an early coastal migration route into the Americas.[1] The D haplogroup is also found in modern Native American populations, which provides a link between Anzick-1 and modern Native Americans.[12]

Nuclear DNA Analysis

Human nuclear DNA is located inside the nucleus of every cell and makes up the human genome.[13] Humans inherit half of their nuclear DNA from their mother and half from their father.[13] Throughout human evolution, mutations occur that are inherited in each subsequent generation.[13] 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.[13] 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]

Y-Chromosome Analysis

The y-chromosome is inherited from father to son in each generation. Because males have an x-chromosome and a y-chromosome, and females have two x-chromosomes, the y-chromosome can only be inherited from an male's father. Specific mutations on the y-chromosome can be used to trace the paternal lineage of a male individual.[13] Like mtDNA, these mutations can be grouped and categorized into haplogroups. The y-chromosome of Anzick-1was sequenced and researchers determined that his y-chromosome haplogroup is Q-L54*(xM3), one of the major founding lineages of the Americas.[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] These findings support the Beringia Hypothesis of the peopling of the Americas and refute the Solutrean Hypothesis.[1]

Beringia Hypothesis

[14][15][16]

Solutrean Hypothesis

The Solutrean Hypothesis posits that modern Native Americans migrated to the New World across the Atlantic Ocean via "ocean current highways."[16] 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.[16] 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.[16] 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.[16]

[17]

Controversy

Native American Graves Protection and Repatriation Act

[18]

Montana State Burial Statutes

[19]

Native American Consultation

References

  1. ^ a b c d e f g h i j k 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 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 e f g h i j 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 Buikstra, Jane E.; Ubelaker, Douglas H. (1994). Standards for Data Collection from Human Skeletal Remains: Proceedings of a Seminar at the Field Museum of Natural History. Arkansas Archaeological Report Research Series. ISBN 978-1563490750.
  7. ^ a b Aufderheide, Arthur C.; Rodriguez-Martin, Conrado (2006). The Cambridge Encyclopedia of Human Paleopathology. Cambridge, United Kingdom: Cambridge University Press.
  8. ^ Walker, Phillip L. (2009). "The Causes of Porotic Hyperostosis and Cribra Orbitalia: A Reappraisal of the Iron-Deficiency-Anemia Hypothesis" (PDF). American Journal of Physical Anthropology. doi:10.1002/ajpa.21031. Retrieved March 24, 2015.
  9. ^ a b Torres Rouff, Christina (Feburary 2002). "Cranial Vault Modification and Ethnicity in Middle Horizon San Pedro de Atacama, Chile". Current Anthropology. doi:10.1086/338290. {{cite journal}}: Check date values in: |date= (help)
  10. ^ Fagundes, Nelson J. R.; et al. (March, 2008). "Mitochondrial Population Genomics Supports a Single Pre-Clovis Origin with a Coastal Route for the Peopling of the Americas". American Journal of Human Genetics. doi:10.1016/j.ajhg.2007.11.013. Retrieved March 22, 2015. {{cite journal}}: Check date values in: |date= (help); Explicit use of et al. in: |first= (help)
  11. ^ Van Oven, Mannis; Kayser, Manfred (October 13, 2008). "Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation". Human Mutation. doi:10.1002/humu.20921. Retrieved March 22, 2015.
  12. ^ Reich, David; et al. (August 16, 2012). "Reconstructing Native American population history". Nature. doi:10.1038/nature11258. Retrieved March 22, 2015. {{cite journal}}: Explicit use of et al. in: |first= (help)
  13. ^ 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)
  14. ^ 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.
  15. ^ Owsley, Douglas W.; Jantz, Richard L. (2014). Kennewick Man : the scientific investigation of an ancient American skeleton. College Station, TX: Texas A&M University Press. ISBN 9781623492007.
  16. ^ a b c d e Peterson, Barbara Bennett (2011). Peopling of the Americas : Currents, Canoes, and DNA. New York: Nova Science Publishers.
  17. ^ 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)
  18. ^ Weimer, Douglas Reid (August 10, 2005). Native American Graves Protection and Repatriation Act (NAGPRA): Legal and Legislative Developments. Library of Congress.{{cite book}}: CS1 maint: year (link)
  19. ^ McClure, Eddye (August, 2000). "MONTANA'S HUMAN SKELETAL REMAINS AND BURIAL SITE PROTECTION ACT: REPATRIATION AND BOARD REIMBURSEMENT" (PDF). Retrieved March 22, 2015. {{cite journal}}: Check date values in: |date= (help); Cite journal requires |journal= (help)
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