ミオセンの注意深い登山:Ardipithecus ramidusと人間の前肢は,原始的なものです
C Owen Lovejoy1, Scott W Simpson, Tim D White
1Department of Anthropology, School of Biomedical Sciences, Kent State University, Kent, OH 44240-0001, USA. olovejoy@aol.com
Science (New York, N.Y.)
|October 8, 2009
まとめ
Ardipithecus ramidusの手と手首は,現代の類人猿とは異なり,原始的な特徴を明らかにし,慎重に登り,手のひらを歩くための適応を示唆しています. これらの発見は,初期のヒト類の移動に関する以前の仮定に異議を唱える.
科学分野:
- 古人類学は,古人類学である.
- 霊長類の解剖学について
背景:
- 初期のホミニドの手と手首の形状を理解することは,運動行動を再構築するために不可欠です.
- 現存する類人猿の解剖学は比較基準となるが,初期のホミノイドには異なる適応がある可能性がある.
研究 の 目的:
- Ardipithecus ramidusの手と手首の解剖を分析するために.
- Arを比較するために. ラミドゥスの前肢の形状はミオセンの類人猿や現存するホミノイドの形状に似ている.
- Arの運動能力を推測するために. 骨格構造に基づいたラミドゥス.
主な方法:
- 化石ホミノイドの手と手首の骨の比較解剖分析.
- 主要な手足と手足下部の特徴の形態学的評価.
- 腹部と肘部文字の検査.
主要な成果:
- Ardipithecus ramidusの手と手首には類人猿から派生した特徴がないため,Proconsul.のようなミオセンの類人猿に似ている.
- カピテートヘッドは,より手首の部分で,極端なミッドカーパルドースフレクションを可能にします.
- マニュアル・プロポーションとメタカルパルの特徴はユニークで,手首の足首の歩行とは関係ありません.
- 前肢複合体は,垂直クライミングやサスペンションのための適応ではなく,palmigradyと注意深く登ることを示唆しています.
結論:
- Ardipithecus ramidusは,現存する類人猿とは異なるユニークな手と手首の形状を有していた.
- ロコモーターの行動には,パルミグラディと注意深い樹木移動が含まれていました.
- この発見は,手足の歩行やサスペンサー行動に適応していない原始的な前肢複合体を示している.
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