ジョージア州ドマニシの初期のホモの新しい頭蓋骨
Abesalom Vekua1, David Lordkipanidze, G Philip Rightmire
1Georgian State Museum, Georgian Academy of Sciences, 3 Purtseladze Street, Tbilisi 380007, Georgia.
Science (New York, N.Y.)
|July 6, 2002
まとめ
ジョージア州ドマニシ (Dmanisi, Georgia) から発見された新しいヒト類の頭蓋骨は,約175万年前のものであることが判明しました. この原始的なホモ・エレクトゥスの化石は,ホモ・エレクトゥス級が出現する前に,アフリカから散らばった初期の人類の祖先を示唆しています.
科学分野:
- 古人類学は,古人類学である.
- 考古学考古学とは
- 地質学 地質学 地質学
背景:
- ジョージア共和国にあるドマニシ遺跡は,著しいホミニドの遺骸を採掘した.
- Dmanisiの以前の発見には,頭蓋骨の部分,動物の化石,石器物が含まれています.
研究 の 目的:
- ドマニシ遺跡から新たに回収されたヒト類の頭蓋骨を分析するために.
- 暫定的に新しい標本をホモ属に分類する.
- 初期のホミニドの分散と進化を理解するために.
主な方法:
- ホミニド化石,動物の化石,石器物の発掘と回収.
- 新しい頭蓋骨の比較解剖分析は,既存のDmanisi標本と他のホミニド化石と比較した.
- ドマニシ遺跡の層の放射線年代測定.
主要な成果:
- 約175万年前にさかのぼる層から,新しいヒト類の頭蓋骨が回収されました.
- 新しい頭蓋骨を含むDmanisiの標本は,ホモ・エレクトス (= ergaster) に割り当てられた最も原始的で小さな脳を持つ化石とみなされています.
- 些細な解剖学的変異にもかかわらず,ドマニシ族の人類は,ハビリスのような幹と密接に関連した単一の分類体を表している可能性が高い.
結論:
- 新しいドマニシの頭蓋骨は,一時的にホモ・エレクトス (= ergaster) に割り当てられています.
- これらの発見は,典型的なホモエレクトス級の進化の前に,初期のホミニド祖先がアフリカから移住したことを示唆しています.
- ドマニシの集団は,初期の人類の進化と分散を理解する上で重要なリンクを代表しています.
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