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巴西的白鸟对鸟类头骨和大脑的演变有所帮助
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
概括
一个新的化石, Navaornis hestiae, 揭示了古老的干鸟和现代鸟类之间的意外相似之处. 这一发现揭示了鸟类头骨和大脑解剖学的演变.
科学领域:
- 古生物学
- 进化生物学
- 比较解剖学
背景情况:
- 了解现代鸟类头骨和大脑的演变是由于保存良好的中生代化石的稀缺而受到限制的.
- 中生代的干鸟 (Enantiornithes) 和现代的鸟 (皇冠鸟) 代表着不同的进化血统.
研究的目的:
- 描述一个新化石物种的头骨和内形态, Navaornis hestiae, 从白纪晚期.
- 为了研究纳瓦尼斯,类鸟和皇冠鸟之间的进化关系.
- 为了澄清现代鸟类神经解剖学的进化组合.
主要方法:
- 详细的形态分析非常保存的Navaornis hestiae化石.
- 植物遗传学分析以确定Navaornis的进化位置.
- 在*Navaornis*和皇冠鸟之间对和内几何学的定量比较.
主要成果:
- *Navaornis hestiae* 拥有没有牙,大眼睛的头骨和形的头骨,类似于王冠鸟.
- 遗传学分析将Navaornis置于中生代的一组鸟类Enantiornithes中.
- 尽管总体几何形状类似于皇冠,但*Navaornis*保留了古老的特征 (例如,大主导的前台,类似的口腔) 以及皇冠式的大脑曲和大型骨迷宫.
结论:
- 纳瓦尔尼斯的头骨形态显示了类鸟和冠状鸟之间显著的融合,挑战了以前的区别.
- *Navaornis*为鸟类神经解剖学的马赛克进化提供了关键的见解,揭示了王冠鸟类的特征在干系中独立演变.
- 这一发现提升了我们对现代鸟类头骨和大脑进化的模式和时间的理解.
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