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Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
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トライアス紀後期のサウリスキアと恐竜の初期の進化の完全な骨格
Sterling J Nesbitt1, Nathan D Smith, Randall B Irmis
1Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA. nesbitt@jsg.utexas.edu
Science (New York, N.Y.)
|December 17, 2009
まとめ
ニューメキシコの新しい恐竜の化石は,初期のセロポッドの進化と鳥の特徴を明らかにしています. この発見は恐竜の多様化を明らかにし,トライアス紀後期に大陸間での広範な分散を示唆している.
科学分野:
- パレオントロジー・パレオントロジー
- 進化生物学の進化生物学について
- 脊椎動物学 脊椎動物学
背景:
- 初期の恐竜の進化を理解することは,トリアシク後期における恐竜の多様化の鍵となる.
- 基礎恐竜の系統の化石は稀で,我々の知識は限られている.
研究 の 目的:
- 初期のセロポッド恐竜の進化史を特徴づけるために.
- 初期の北米の恐竜の多様化を調査するために.
- 鳥類の特徴体系の古代についての洞察を提供するために.
主な方法:
- ニューメキシコの新しいセロポッド恐竜のほぼ完全ないくつかの骨格の発掘と分析.
- プレシオモルフィックおよび派生特徴に焦点を当てた比較解剖学的研究.
- トライアス紀後期のサウリスキア群の古生物学地理学的分析.
主要な成果:
- 新しい分類は,原始的および高度な特徴のモザイクを示し,初期のサウリスキアの進化を明らかにします.
- 重要な鳥の特徴である骨格の肺動性の初期の存在の証拠が見つかりました.
- この研究では,トライアス紀後期のサウリスキア群の緯度差が明らかになった.
結論:
- 発見されたセロポッド恐竜は,初期の恐竜の進化と多様化に関する重要な情報を提供します.
- この発見は,トライアス紀後期北米のセロポッド動物群が固有の存在ではなかったことを示唆し,大陸間分散が盛んであったことを示唆している.
- この研究は,初期のセロポッドにおける鳥類の骨格の特徴の古代を強調しています.
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