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鳥の頭蓋骨と脳の進化を 教えてくれる ブラジル産の白亜紀の鳥
Luis M Chiappe1, Guillermo Navalón2, Agustín G Martinelli3
1Dinosaur Institute, Natural History Museum of Los Angeles County, Los Angeles, CA, USA. lchiappe@nhm.org.
Nature
|November 13, 2024
まとめ
新しい化石 Navaornis hestiaeは 古代の幹鳥と現代の鳥の間に 予期せぬ類似性を明らかにしています この発見は 鳥の頭蓋骨と脳構造の進化に 光を当てました
科学分野:
- 古生物学
- 進化生物学
- 比較解剖学
背景:
- 現代の鳥の頭蓋骨と脳の進化の理解は,保存された中期化石の希少さによって制限されています.
- 中生期の幹鳥 (エナティオルニテス) と現代の鳥 (クラウン・バード) は 異なる進化の系統を表しています
研究 の 目的:
- 新種の化石の頭蓋骨と内頭蓋骨の形状を記述する ナヴァオルニス・ヘスティア 紀後期
- ナバオルニス,エナティオルニチン,クラウンバードとの進化的関係を調査する.
- 現代の鳥の神経解剖学の 進化的組み立てを説明するために
主な方法:
- 詳細な形態学的分析 保存状態が非常に良いNavaornis hestiaeの化石
- ナバオルニスの進化的位置を決定する 系統遺伝分析
- *ナバオルニス*,エナティオルニチン,冠鳥の頭蓋骨と内頭蓋骨の幾何学的な比較
主要な成果:
- *ナヴァオルニス・ヘスティア (Navaornis hestiae) *は歯のない大きな目を持つ頭蓋骨を持ち,冠鳥に似ています.
- 系統遺伝学的な分析により,ナヴァオルニスは中期期の幹鳥のグループであるエナティオルニスに属している.
- 冠状の整体幾何学にもかかわらず, *Navaornis* は古代の特徴 (例えば,頭が支配するロストラム,アキネティック・パラテ) を冠状の脳屈曲と大きな骨の迷宮とともに保持しています.
結論:
- ナバオルニスの頭蓋骨の形状は,エナティオルニスとクラウン鳥の間の驚くべき収束を示し,以前の区別に挑戦しています.
- 鳥の神経解剖学のモザイク進化に重要な洞察を与えており,冠鳥のような特徴が幹の系統で独立して進化したことを示しています.
- この発見により 現代の鳥の頭蓋骨と脳の進化のパターンの理解が 洗練されました
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