まとめ
ユハ骨格の新しい放射性炭素年代測定により,その年齢が4000年未満であることが明らかになった. このホロセーン時代は,西半球における初期の人類集団の,はるかに古い,プレイストセーン後期の起源に関する以前の主張と矛盾しています.
科学分野:
- 考古学考古学とは
- パレオントロジー・パレオントロジー
- ラジオメトリック・デッティング
背景:
- 西半球に人類が到着したのは議論の余地があり,一部の遺跡は,放射性炭素年約12,000年という既定のタイムラインに異議を唱えている.
- カリフォルニアのユハ墓地では,紀元前2万年以上とされているが,この議論の焦点となっている.
研究 の 目的:
- ホモ・サピエンス・サピエンス・ユハの骨格の年齢を正確に決定するために.
- 以前の年代測定方法と埋葬の考古学的な文脈の間の不一致を解決するために.
主な方法:
- 放射性炭素年代測定 (14C/13C比) は,骨格の骨の複数の有機および無機分子を,タンデム加速器質量スペクトロメーターを使用して測定したものです.
- カリチェのコーティング,文化的文脈,地形学,アミノ酸のラセミゼーションを含む以前の年代測定結果の分析.
主要な成果:
- ユハの骨格から採取した6つの化学分子の放射性炭素年代測定は,一貫して,放射性炭素年数B.P.の4000年未満の年齢を示した.
- これらの結果は,骨格のホロセンの年齢を強く示すものであり,以前のプレイストセンの年齢割り当て (19,000-23,000 yr BP) と矛盾しています.
結論:
- ユハ骨格はホロセーン時代のものであり,その文化的な文脈と一致しています.
- この発見は,ユハの埋葬の古さと,西半球への早期の人類の移住への影響について異議を唱えている.
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