後期プレイストセンのヒト骨格とmtDNAのリンク パレオアメリカンと現代のネイティブアメリカン
James C Chatters1, Douglas J Kennett2, Yemane Asmerom3
1Applied Paleoscience and DirectAMS, 10322 NE 190th Street, Bothell, WA 98011, USA. paleosci@gmail.com.
Science (New York, N.Y.)
|May 17, 2014
まとめ
遺伝的証拠と13,000年前の骨格は,パレオアメリカンとネイティブアメリカンの祖先を共有することを示唆しています. 面の差異は,個別の起源ではなく, in situ 進化から生じた可能性が高い.
科学分野:
- 古人類学は,古人類学である.
- 人間の遺伝学 人間の遺伝学
- 考古学考古学とは
背景:
- 初期のアメリカの骨格は,現代のネイティブアメリカンと比較して,明確な頭蓋骨の特徴を示しています.
- この形態学的分岐は,これらの集団の個別の起源の理論につながった.
- しかし,遺伝データは共通の祖先を示唆している.
研究 の 目的:
- ユニークな骨格の発見を分析することによって,初期のアメリカ人の起源を調査する.
- パレオアメリカンとネイティブアメリカンの祖先に関する遺伝的証拠と形態学的違いを調和させる.
- 面の変異が別々の起源か,あるいは in situ 進化を示すかどうかを判断する.
主な方法:
- 無傷の頭蓋骨と保存されたDNAを含む,ほぼ完全な人間の骨格の分析.
- 骨格の放射性炭素年代測定は13,000〜12,000カレンダー年前のものです.
- ミトコンドリアDNA (mtDNA) のハブログループ分析により,遺伝的系統を決定する.
主要な成果:
- 骨格は,古代アメリカ人の頭蓋骨顔の特徴を示しています.
- DNA分析により,ベリンギア系から派生したミトコンドリアDNAハプラグループ (D1) が明らかになった.
- この骨格は,メキシコのユカタン半島にある水中に沈んだ洞窟で,絶滅した動物たちと一緒に発見された.
結論:
- この発見は,古アメリカ人とネイティブアメリカンの単一の起源を支持しています.
- 面の違いは,アメリカ大陸における in situ 進化の結果である可能性が高い.
- これは,初期のアメリカ人の祖先集団が異なっていたという以前の仮説に異議を唱えている.
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