東アフリカにおけるケノゾイク後期の湿度史

Martin H Trauth¹, Mark A Maslin, Alan Deino

¹Institut für Geowissenschaften, Universität Potsdam, Post Office Box 601553, D-14415 Potsdam, Germany.

Science (New York, N.Y.)

|August 20, 2005

まとめ

東アフリカ湖の沈殿物は,過去3つの湿気期を明らかにし,初期の人類の進化に影響を与えた. これらの湿気期は,地球規模の気候変動とアフリカの乾燥と一致し,哺乳類とヒト類の分散に影響を与えました.

科学分野:

古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
古人類学は,古人類学である.
地質学地質学地質学

背景:

東アフリカの気候は,長期にわたる乾燥化を経験しています.
過去の気候の変動を理解することは,人間の進化の研究にとって極めて重要です.

研究の目的:

東アフリカのリフト盆地における過去の湿気期を復元するために.
これらの湿気期と地球規模の気候変動との相関を調査する.
これらの気候変動がヒト類と哺乳類の進化に及ぼす潜在的な影響を評価する.

主な方法:

エチオピア,ケニア,タンザニアの10のリフト盆地からの湖の堆積物の分析.
過去の気候イベントのタイムラインを確立するために堆積層の年代測定.

主要な成果:

3つの異なる湿気期を特定した: 2.72.5 Ma, 1.91.7 Ma,および 1.10.9 Ma.
これらの湿気期間の相関関係と北西および北東アフリカの干ばつの増加.
これらの湿気エピソードが,地球的な気候変動と関連している.

結論:

これらの湿度の高い時期は,哺乳類とヒト類の種化と拡散に影響を与えた可能性がある.
ホモの起源とホモ・エレクタスの進化を含む主要なホミニンイベントは,これらの気候変化の間に発生しました.
東アフリカにおける過去の気候の変動は,人類の進化の初期に重要な役割を果たしました.

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