北米のオレゴン州にあるクロビス以前のヒトコプロライトのDNA
M Thomas P Gilbert1, Dennis L Jenkins, Anders Götherstrom
1Centre for Ancient Genetics, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen, Denmark.
Science (New York, N.Y.)
|April 5, 2008
まとめ
アメリカ大陸における初期の人間の存在は,オレゴン州からの古代DNA証拠によって確認されており,クロビス文化より1000年以上前のものである. この発見は,北米への最初の人間の移住のタイムラインを確立しました.
科学分野:
- 考古学考古学とは
- パレオゲネティクス パレオゲネティクス
- アントロポロジー人類学
背景:
- アメリカ大陸への最初の人間の移住のタイムラインは,現在進行中の議論の対象です.
- クロビス技術複合体の出現は,現在より約 11,000 〜 10,800 放射性炭素年前の (14C B.P.年) 年代である. ) は,重要な基準点である.
研究 の 目的:
- 北アメリカにおける人間の存在のタイミングを調査する.
- クロビス・コンプレックスより前に,北米の土地に人類が住んでいたかどうかを判断する.
主な方法:
- オレゴン州ペイスリー5マイルポイント洞窟で発見された古代コプロライトからヒトミトコンドリアDNA (mtDNA) の回収.
- 加速器質量スペクトロメトリ (AMS) を使用したコプロライトの直接年代測定.
- haplogroupsを特定するためにmtDNAの分析.
主要な成果:
- 人間のmtDNAは,ペイスリー5マイルポイント洞窟のコプロライトで特定されました.
- 回収されたmtDNAは,アメリカ先住民の創始ハプラグループA2とB2に属している.
- コプロライトの直接的な年代測定は,紀元前12,300年,クロビス複合体より1000年以上早く,紀元前14C年の年代を示した.
結論:
- オレゴン州中南部には,少なくとも12300年B.P. 14C年前に人類がいた.
- この人間の存在は,クロビス技術複合体よりかなり前のものです.
- この発見は,以前に確立されたことよりも,アメリカ大陸への最初の人間の移住がより早く起こったことを示唆しています.
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