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Updated: May 11, 2026

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鳥のような化石の足跡は,トライアシク後期に遡ります
Ricardo N Melchor1, Silvina De Valais, Jorge F Genise
1CONICET and Universidad Nacional de La Pampa, Av. Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina. melchor_r@cpsarg.com
Nature
|June 28, 2002
まとめ
アルゼンチンの恐竜の足跡.
科学分野:
- パレオントロジー・パレオントロジー
- 脊椎動物の古生物学について
- この技術は,
背景:
- 鳥類の化石記録は,ジュラ紀後期にアーキオプテリックスから始まる.
- 鳥類の祖先 (コエルロサウル) は,ジュラ紀初期まで遡ります.
- トライアス紀後半のセロポッドには,逆ハルクスのような鳥の特徴の骨格的証拠がない.
研究 の 目的:
- 鳥類の特徴を持つ新しい化石の足跡を記述する.
- 鳥類の起源と進化を,鳥類技術を通して研究する.
- 鳥類の進化に関する既存のタイムラインに異議を唱える.
主な方法:
- アルゼンチンのトライアス紀後半の赤床からの保存状態の良い化石の足跡の分析.
- 鳥類の特徴を特定するための比較イチノロジカル分析.
- 堆積環境のパレオ環境再構築.
主要な成果:
- 明確な鳥類の特徴を示す足跡の豊富な発見.
- これらの痕跡は,知られている最も古い鳥の骨格化石よりも少なくとも5500万年前のものです.
- 足跡は,トライアシク後期に鳥の特徴を持つセロポッドの存在を示唆しています.
結論:
- この発見は,鳥類の特徴がセロポッドに存在するという既知の起源をトライアス紀後期に遡らせている.
- イチノロジーは,鳥類の進化を理解するための重要な証拠を提供します.
- これらの痕跡は,初期の鳥類に近似した未知のセロポッド群を表しています.
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