初期の恐竜を含むマダガスカルのトリアス期の動物
Flynn1, Parrish, Rakotosamimanana
1Department of Geology, The Field Museum, Chicago, IL 60605, USA. Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA. Département de Paléontologie et d'Anthropologie Biologique, Université d'Antananarivo, Antananarivo 101, Madagascar. Department of Geology, University of California, Santa Barbara, CA 93106, USA.
Science (New York, N.Y.)
|October 26, 1999
まとめ
マダガスカルで発見された化石は,トリアス紀中期から後期にかけての初期の恐竜を明らかにしています. この新しい脊椎動物ファウナは,化石記録のギャップを埋めて,恐竜の時代について光を当てています.
科学分野:
- パレオントロジー・パレオントロジー
- 脊椎動物学 脊椎動物学
- ストラティグラフィー ストラティグラフィー
背景:
- トライアス紀中後期は,初期の恐竜の進化を理解する上で極めて重要です.
- この特定の時間間の大陸の脊椎動物の化石記録は,世界的に稀です.
- マダガスカルの地質学の歴史は,ユニークな化石の集合を保存する可能性を秘めています.
研究 の 目的:
- マダガスカルで重要な陸上脊椎動物が発見されたことを報告する.
- 世界的な化石記録における,代表が不十分な時間間隔を記録する.
- 恐竜の初期の進化と多様化を調査する.
主な方法:
- フィールド発掘と化石化した遺骸の発見.
- 化石を含む層の地質年代測定.
- 発見された脊椎動物の化石の比較解剖学的分析.
- 進化的関係を決定するための系統遺伝分析.
主要な成果:
- トライアス紀中期から後期までの地上の脊椎動物群の識別.
- プロザオロポッド恐竜の2つの新種の発見.
- 野生動物は,世界中で知られている最古の恐竜の発生の1つを表しています.
- このアセンブラージは,恐竜が支配するトライアシク後期の生態系への移行についての洞察を提供します.
結論:
- マダガスカルの動物群は,トライアス期の脊椎動物の進化を理解するために不可欠です.
- この発見は,考古学的な研究のために,十分に調査されていない地域の重要性を強調しています.
- この発見は,初期の恐竜の起源と多様化に関する私たちの知識に大きく貢献しています.
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