マダガスカルの白亜紀後期に生息していた奇妙な捕食恐竜
S D Sampson1, M T Carrano, C A Forster
1Utah Museum of Natural History and Department of Geology and Geophysics, University of Utah, Salt Lake City 84112-0050, USA. ssampson@umnh.utah.edu
Nature
|February 24, 2001
まとめ
マダガスカルで新しい捕食恐竜,マシアカサウルス・ノップフレリが発見されました. この小さなセロポッドは,以前は恐竜では知られていなかった,独特で前向きな歯を特徴としており,古代の爬虫類の分布がより広いことを示唆しています.
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
- 進化生物学の進化生物学について
背景:
- クレタ紀後期には,ゴンドワナ全土で多様な恐竜が暮らしていた.
- アベリサウロイドは,主により大きな種から知られている,セロポッド恐竜の重要なグループでした.
- 小型のアベリサウロイドは以前はアルゼンチンでのみ記録されていた.
研究 の 目的:
- マダガスカルで新種の恐竜が発見されたことを報告するためです.
- この新しいセロポッドのユニークな歯と骨格の特徴を説明するために.
- この発見の進化的および生物地理的意味を推論する.
主な方法:
- 化石化した頭蓋骨と頭蓋骨後遺体の発掘と分析.
- 既知の恐竜の分類体との比較解剖学的研究.
- 系統遺伝分析は,分類的関係を決定する.
主要な成果:
- マシアカサウルス・ノップフレリ (Masiakasaurus knopfleri) の発見は,小さな (約. 1.8m) 肉食恐竜. 肉食恐竜. 肉食恐竜. 1.8m) 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜. 肉食恐竜.
- 独特のヘテロドントとプロクンブントの下歯,セロポッドでは前例のない.
- 骨格の特徴は,MasiakasaurusがAbelisauroidea cladeのメンバーであることを確認しています.
結論:
- Masiakasaurus knopfleriは,マダガスカルのアベリササウロイド型セロポッドの新しい属と種を表しています.
- そのユニークな歯は,セロポッドの餌戦略と歯の進化に関する新しい洞察を提供します.
- この発見は,小型のアベリサウロイドの既知の地理的範囲を拡大し,ゴンドワナの分布と多様性がより広いことを示しています.
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