アウストラロピテクス・セディバの脊柱
Scott A Williams1, Kelly R Ostrofsky, Nakita Frater
1Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY 10003, USA. sawilliams@nyu.edu
Science (New York, N.Y.)
|April 13, 2013
まとめ
アウストラロピテクス・セディバは,ホモ・エレクタスに似たような,より長い背中の下部を持つ柔軟な脊椎を持っていた. この発見は,初期のヒトの脊椎の進化と姿勢に関する新しい洞察を提供します.
科学分野:
- 古人類学は,古人類学である.
- プリマトロジー・プリマトロジー学
- 人間の進化 人類の進化
背景:
- 初期のホミニンの脊椎の解剖学を理解することは,運動と行動を再構築するために不可欠です.
- 以前のオストラロピテクスの脊椎構造の解釈は様々だった.
研究 の 目的:
- Australopithecus sedibaの脊柱を分析して,脊髄の移動性,腰椎の曲率,脊椎の配列を決定する.
- Auの脊椎解剖を比較するために. 現代のヒトやホモ・エレクトゥスを含む他のホミニン類と共存していた.
主な方法:
- アウストラロピテクス・セディバ (Australopithecus sediba) に由来する2つの部分的脊柱の検査.
- 椎間板の形状の分析により,腰椎の曲線,椎間板の形状,および移行性椎間板の位置を推測する.
主要な成果:
- Au. オー. オー. オー. セディバには,おそらく5つの腰椎と5つの交尾椎があり,人間のモダルの構成と一致していた.
- 最後の肋骨を担う脊椎の上の明確な移行椎は,機能的に長い下背中を示唆しています.
- ロードティックな姿勢と状の腰椎の証拠は,非常に柔軟な脊椎を示しています.
結論:
- Au.の脊椎解剖学について sedibaは,より初期のオストラロピテコス種とは異なる,派生した,非常に柔軟な脊椎を示しています.
- この脊椎の構成はホモ・エレクタスのものとより類似しており,収束進化または共通の祖先を示唆しています.
- この発見は,初期のヒトの脊椎数と脊椎の進化に関する以前の解釈に異議を唱えている.
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