まとめ
東アフリカにおける中石器時代は18万年以上前に始まり,以前の推定より先行した. この発見は,中石器時代の技術開発の古さよりもはるかに大きいことを明らかにします.
科学分野:
- 古人類学は,古人類学である.
- ジオクロノロジー (Geochronology) について
- 考古学考古学とは
背景:
- 中石器時代 (MSA) は,アフリカにおける人類進化の重要な時期である.
- 東アフリカにおけるMSAの起源に関する以前の推定は,それほど確実ではなかった.
- 火山材料の年代測定は,タイムラインを確立するための信頼できる方法を提供します.
研究 の 目的:
- 東アフリカにおける中石器時代の古代を決定する.
- 中石器時代の技術発展の始まりの最低年齢を定めること.
- リフト・バレー地域の新しい年代データを提供するために.
主な方法:
- カリウム-アルゴン年代測定は,サニジン結晶で行われました.
- サンプルは結晶に富んだパンテレライトと火山灰から採取した.
- 地質学的背景は,エチオピア中部のメイン・リフト・バレーでした.
主要な成果:
- 3つの年齢決定は,一貫して18万年前より前の年齢を示しました.
- この年齢は,中石器時代に関連した火山材料に適用されます.
- 発見は,この地域のMSAの最低年齢を確立しています.
結論:
- 東アフリカにおける中石器時代は,以前考えられていたよりもかなり古い.
- MSAの技術革新は,より古くから存在しています.
- この研究は,アフリカにおける人類の初期の技術史についての理解を修正するものです.
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