ステルクフォンテインのメンバー2のアウストラロピテカスとメンバー5のオルドワンの新しい宇宙的埋葬年齢
Darryl E Granger1, Ryan J Gibbon2, Kathleen Kuman3
1Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, USA.
Nature
|April 2, 2015
まとめ
スタークフォンテイン (Sterkfontein) とは,スタークフォンテイン (Sterkfontein) とは,シュタークフォンテイン (Sterkfontein) とは,シュタークフォンテイン (Sterkfontein) とは,シュタークフォンテイン (Sterkfontein) とは,シュタークフォンテイン (Sterkfontein) とは
科学分野:
- 南アフリカのホミニン遺跡の古人類学と地質学.
背景:
- ステルクフォンテイン洞窟の埋蔵物は,豊かなオーストラリアロピテカスの化石と初期の石器具を収容しています.
- スタークフォンテインでの以前の年代測定研究は,複雑な洞窟埋蔵と年代測定の不確実性のために論争に直面しています.
研究 の 目的:
- ステルクフォンテイン洞窟の埋蔵物,特にStW 573 ('Little Foot') の骨格と初期の石器具の信頼性の高い年代順を確立するために.
- 以前の年代測定方法の不一致を解決し,重要な化石や人工物発見の正確な年代を提供するためです.
主な方法:
- コスモゲンイソトープアルミニウム-26とベリリウム-10を用いたアイソクロン埋葬年代測定.
- デッティングサンプルの完全性を確保するために,堆積物の再処理の分析.
主要な成果:
- StW 573の骨格を含むブレチヤは,3.67 ± 0.16百万年前に堆積され,初期のAustralopithecus afarensisと同時代であることを示しています.
- ステルクフォンテインの石器の最古は218 ± 0.21万年前と年代付けされており,オルドワンの産業と一致しています.
結論:
- 新しい年代測定は,Sterkfonteinで長年にわたる時間論的な議論を解決します.
- この発見は,南アフリカにおける初期のヒト類の活動と道具の使用を,より正確な時間枠内に配置し,東アフリカの発見と相関しています.
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