マダガスカルからの捕食性恐竜の遺骸:ゴンドワナの白期の生物地理学への影響
1S. D. Sampson, Department of Anatomy, New York College of Osteopathic Medicine of New York Institute of Technology, Old Westbury, NY 11568, USA. L. M. Witmer, Department of Biomedical Sciences, College of Osteopathic Medicine, Ohi.
Science (New York, N.Y.)
|May 22, 1998
まとめ
マダガスカルからの新しいアベリサウリド恐竜の化石は,ユニークな頭蓋骨の特徴を持つ大きなセロポッドを明らかにしています. その分布は,ゴンドワナの陸地とのつながりが白亜紀後期まで続いたことを示唆している.
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
- 地質学 地質学 地質学
背景:
- マダガスカルでの化石発見は,新しい脊椎動物の標本をもたらしました.
- クレタ紀後期は,恐竜の進化と古生物地理学の理解に極めて重要です.
研究 の 目的:
- マダガスカルで新たに発見された大型セロポッド恐竜の化石を記述し,分類する.
- アベリサウリドの分布の古生物学地理学的意味を分析する.
主な方法:
- 化石標本の比較骨質学.
- 分類学的な位置づけを決定するための系統遺伝分析.
- 化石の分布に基づいた古地理学的再構築.
主要な成果:
- 大型のセロポッド恐竜のほぼ完全な頭蓋骨が発見され,空気鼻,前頭角,頭部突起などのユニークな特徴があります.
- 新しい標本をアベリサウリidaeファミリーに割り当てます.
- 化石アベリサウリドは南米,マダガスカル,インドで発見されており,ゴンドワナの陸地が以前考えられていたよりも長く繋がっていたことを示唆しています.
結論:
- 新しいアベリサウリドの化石は,ゴンドワナの後期白期のセロポッドの多様性に関する重要な洞察を提供します.
- 分布パターンは,南極大陸経由で,クレタセア紀後期まで延長された陸上接続を持つ改訂された古地理モデルをサポートしています.
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