Ardipithecus ramidusの地質学,同位体学,植物学,無脊椎動物,下脊椎動物を取り巻く環境について
Giday WoldeGabriel1, Stanley H Ambrose, Doris Barboni
1Earth Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. wgiday@lanl.gov
Science (New York, N.Y.)
|October 8, 2009
まとめ
エチオピアで発見されたArdipithecus ramidusの化石は,4400万年前に湿った森林に古代のヒト類が住んでいたことを示しています. 地質学的および古生物学的データは,彼らの環境と生息地好みを明らかにします.
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
- パレオエコロジー (古生態学)
背景:
- Ardipithecus ramidusを含む堆積物は440万年前のものである.
- ホミニドを産むユニットは,エチオピア西部のアファー裂域に位置しています.
- このユニットは,アルゴン-アルゴン (40Ar/39Ar) 年代が似た2つの火山タフの間に位置しています.
研究 の 目的:
- Ardipithecus ramidusの古生物学環境を再構築するために.
- 初期のホミニドが占拠していた生息地を決定する.
主な方法:
- 沈殿堆積物の地質学的分析.
- 植物,無脊椎動物,脊椎動物の化石の古生物学的調査.
- 化石関連のタフォノミクス分析.
- フィトリート分析. フィトリート分析.
- ペドジェニック炭酸塩の安定同位体分析 (酸素と炭素).
主要な成果:
- 証拠によると,Ardipithecus ramidusは森のある生息地に住んでいた.
- その生息地は,研究された古流域の西部の4分の3をカバーしていた.
- 植物石と安定した同位体は,草のある基板を持つ湿気があり,涼しい森林地帯を示しています.
結論:
- Ardipithecus ramidusは複雑な森林環境で生息していました.
- 発見は,初期のホミニドの生態学的ニッチと適応についての洞察を提供します.
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