胸骨特征的扩大促进了鸟类动力飞行的进化
Talia M Lowi-Merri1,2,3, Roger Benson4, Han Hu5
1Department of Anatomy, New York Institute of Technology, College of Osteopathic Medicine, Old Westbury, NY, USA. talialowimerri@gmail.com.
Nature ecology & evolution
|July 24, 2025
概括
鸟的胸骨的进化不是线性的. 早期鸟类的亲属有小的头,这些头随着时间的推移而扩大并形成,使得后来的物种能够使用动力飞行.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 生物力学 生物力学
背景情况:
- 现代鸟类拥有扩大的大和突出的,对于飞行至关重要.
- 早期飞禽类和非飞禽类恐龙 (Pennaraptora) 的骨显著不同或不存在,阻碍了对骨进化和功能的理解.
- 化石记录的碎片性和保存挑战使早期鸟类胸骨结构的研究变得复杂.
研究的目的:
- 重建鸟类干群中骨特征的进化历史.
- 使用遗传学方法分析胸骨形态,体重和飞行能力之间的关系.
- 了解胸部进化对鸟类动力飞行发展的功能影响.
主要方法:
- 祖先特征估计,以追踪胸部特征的演变.
- 多变量系遗传回归以将胸骨形态与身体质量和飞行相关联.
- 在化石和现存的鸟类血统中对胸部结构的比较分析.
主要成果:
- 骨进化是偶发的,最初的小骨是在基底的Pennaraptora.
- 骨在Avialae中扩大和延长,在Pygostylia中出现基尔前体的出现之前.
- 在Ornithuromorpha中发生了进一步的胸骨扩大,部发育和尾部投射增长,增强了飞行肌肉的附着.
- 在Pennaraptora中观察到多个部适应飞行的实例,包括Paraves和Enantiornithes.
结论:
- 鸟类胸骨的进化涉及不同的尺寸增加和形态发展阶段.
- 胸部基尔和相关结构的发展是一个渐进的过程,对动力飞行的演变至关重要.
- 动力飞行可能在皇冠群鸟在广泛扩散之前,在更广泛的鸟类谱系内独立地多次演变.
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