シノーニソサウルスの枝分かれした体構造と羽根の起源
1Institute of Vertebrate Paleontology and Paleoanthropology, Academica Sinica, PO Box 643, Beijing, 100044, People's Republic of China.
Nature
|March 10, 2001
まとめ
Sinornithosaurus milleniiの化石証拠は,原始的な羽毛を明らかにし,その起源を非鳥類のセロポッド恐竜で支持しています. これらの羽状の構造は,鳥の進化に関する重要な洞察を提供します.
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
- 恐竜の研究について
背景:
- 羽毛の進化的起源と恐竜との関連は議論の余地がある.
- 以前のセロポッドの繊維状構造の発見は,明確な羽の同質性を持っていなかった.
研究 の 目的:
- 基礎ドロメオサウルスの恐竜,シノルニソサウルス・ミレニアの体付属体のホモロジーを調査する.
- 非鳥類のセロポッドにおける羽根の起源に関する明確な証拠を提供すること.
主な方法:
- Sinornithosaurus milleniiの化石から採取したフィラメント状の整体付属体の顕微鏡検査.
- 付属体の形状を,既知の鳥羽と比較した分析.
主要な成果:
- シノルニソサウルスの付属体は,複数の繊維で構成された複合構造です.
- これらの構造は,鳥の羽毛に見られるユニークな枝分かれパターン (基礎,連続配列) を表しています.
- 系統遺伝学的証拠は,鳥類のセロポッドの祖先を支持しています.
結論:
- シノーニソサウルスの体付属体は,鳥の羽と同類である.
- この発見は,羽毛が非鳥類のセロポッド恐竜で進化したという仮説を強く支持しています.
- これらの原始的な羽根は,羽根の進化の発達モデルと一致しています.
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