南アフリカの中石器時代の時代:人間の行動と分散への影響
Zenobia Jacobs1, Richard G Roberts, Rex F Galbraith
1GeoQuEST Research Centre, School of Earth and Environmental Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia. zenobia@uow.edu.au
Science (New York, N.Y.)
|November 1, 2008
まとめ
8万~6万年前のアフリカからの現代人の拡大は,南アフリカのイノベーションと一致しています. スティル・ベイとホワイソンのプート産業は,7,000年という短い間隔で,気候のみが原因ではなかった.
科学分野:
- 古人類学とアフリカ史前史.
- 考古学的年代測定と行動進化.
背景:
- 現代のヒトがアフリカから (8万~6万年前) 広がったのは,中石器時代の革新と結びついている.
- 南アフリカのスティル・ベイとホワイソンのプート産業は,初期の象徴的な行動と個人的な装飾品を示しています.
- 以前の年代順は,これらの出来事の正確な順序とタイミングを確立するのに不十分でした.
研究 の 目的:
- ステル・ベイ産業とホワイソンのポート産業の正確な時間的枠組みを確立するために.
- これらの技術的段階を,人類の人口拡大と移住の遺伝的推定値と相関させる.
- これらのイノベーションの時期の背後にある環境的要因を調査する.
主な方法:
- 南アフリカ全土の9つの考古学遺跡から採取した遺物や堆積物の放射線年代測定.
- 研究対象地域からの多様な気候と生態学的データの分析.
- 人口移動に関する既存の遺伝データと確立された年代順の比較.
主要な成果:
- スティル・ベイ産業とホワイソンのプート産業は,いずれも短命で,5,000年かそれ以下しか続かなかった.
- この2つの産業は,約7000年の間隔があった.
- これらの産業の時期は,人類の人口拡大とアフリカからの脱出に関する遺伝的推定値と一致しています.
- 革新の時期は,環境要因にのみ帰属するものではありませんでした.
結論:
- この研究は,中石器時代の重要な産業の強固な年代表を提供し,人類の起源についての理解を洗練しています.
- この発見は,技術革新,象徴的な行動,そして現代人のアフリカからの分散との関連を裏付けている.
- 環境的要因だけでは,人類進化のこれらの重要な期間中に観察されたイノベーションの爆発を説明することはできません.
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