スペインのプレイストセンの中期からの完全な人間の骨盤
J L Arsuaga1, C Lorenzo, J M Carretero
1Departamento de Paleontología, Instituto de Geología Económica, Facultad de Ciencias Geológicas, Universidad Complutense de Madrid, Spain. azara@eucmax.sim.ucm.es
Nature
|June 3, 1999
まとめ
スペインのSima de los Huesos遺跡から発見された化石は,ネアンデルタール人の祖先である古代ホミニドを原始的な骨盤で明らかにしています. 彼らの小さな脳の大きさは,現代の人間とネアンデルタール人との異なる進化の経路を示唆しています.
科学分野:
- 古人類学は,古人類学である.
- 人間の進化 人類の進化
- 史前考古学 史前考古学 歴史以前の考古学
背景:
- スペインのSima de los Huesos遺跡には,少なくとも33人のホミニド個体の2,500以上の化石が含まれています.
- 化石は20万年以上前のもので,ネアンデルタール人の祖先と考えられています.
研究 の 目的:
- Sima de los Huesosからのほぼ完全な男性骨盤 (骨盤1) と関連する股関節の形態論を分析する.
- これらの中期プレイストセンのホミニドの骨盤と頭蓋骨の特徴をネアンデルタール人と現代人と比較するために.
主な方法:
- 骨盤1および関連する股関節の形態学的分析.
- 骨盤と股関節の形態学に基づいて体重の推定.
- 頭蓋骨の容量を用いた脳化分数の計算.
主要な成果:
- 骨盤1は頑丈で広い構造を持ち,上部に長い pubis ramusと顕著な iliac flareがあり,原始的な骨盤の形を示唆しています.
- 骨盤運河は,現代の新生児にとって十分な大きさであり,大体の子孫の可能性を示しています.
- 個人の推定体重は95kg以上です.
- エンセファライゼーション割合はネアンデルタール人や現代人よりも著しく低い.
結論:
- 骨盤の形状は,現代人とネアンデルタール人の分岐に先立ち,原始的な状態を表しています.
- シマ・デ・ロス・ウエソスのヒト類は,原始的な特徴と派生的な特徴のモザイクを持ち,初期の人類の進化の洞察を提供しました.
- 彼らの小さな頭蓋骨容量は,後のヒト類と比較して異なる進化の軌道を示唆しています.
関連する概念動画
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