古代の食生活における海洋対陸上のタンパク質の尺度としての安定炭素同位体比
まとめ
安定した炭素同位体比は,海洋と陸上の動物の肉の明確な違いを明らかにします. 人間のコラーゲンのこれらの炭素同位体値 (デルタ ((13) C) は,史前時代の食生活を再構築することができます.
科学分野:
- パレオエコロジー (Paleoecology) とは
- イソトープ地球化学 イソトープ地球化学
- 考古学考古学とは
背景:
- 海洋と陸上の生態系は,炭素の安定した同位体シグネチャーを有する.
- これらの同位体差異は,ヒトを含む最高消費者の食物網を通して追跡できます.
- これらのシグネチャーを理解することは,過去の環境と食生活を再構築するために不可欠です.
研究 の 目的:
- カナダの太平洋沿岸の海洋および陸上の動物における安定した炭素同位体比を調査する.
- これらの同位体差が人間の消費者に反映されているかどうかを判断する.
- 人類のコラーゲンにおける炭素同位体値 (デルタ) の有用性を確立し,史前時代の食生活を分析する.
主な方法:
- 動物の肉サンプルにおける安定炭素同位体比 (デルタ) の分析.
- 海洋動物と陸生動物間の同位体値の比較.
- 人間のコラーゲンの炭素同位体値の測定.
主要な成果:
- 海洋と陸上の動物の肉の間で,7.9 +/- 0.4 per milの有意な違いが観察されました.
- この同位素分割は,海洋と大気中の炭素貯蔵庫の間の既知の違いを反映しています.
- ヒトコラーゲンの炭素同位体値は,消費された海洋と陸上の食物源の比率と直接相関しています.
結論:
- 安定炭素同位体分析は,過去の集団における海洋と陸上の食物消費を区別するための信頼できる方法を提供します.
- 史前の人間の食事は,そのコラーゲンのデルタ (13C) 値を分析することによって定量的に評価することができます.
- この研究は,過去の沿岸地域の生計戦略と資源利用の理解を深める.
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