羽毛的起源和早期演变:含义,不确定性和未来前景
Xing Xu1,2, Paul M Barrett3
1Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China.
Biology letters
|February 19, 2025
概括
羽毛在鸟类之前逐渐变得越来越复杂,早期的形式与现代的形式不同. 了解羽毛的起源需要更多关于恐龙和进化途径的数据.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 发展生物学 发展生物学
背景情况:
- 羽毛是鸟类的决定性特征,对于理解鸟类生物学至关重要.
- 化石发现揭示了恐龙和类恐龙的羽毛进化,显示了飞行羽毛的日益复杂性和获得在鸟类之前.
- 与现代羽毛相比,早期的羽毛表现出形态,超结构,生化和发育方面的差异,表明了独特的进化路径.
研究的目的:
- 调查"真实"羽毛的起源在Avemetatarsalia (包括鸟类及其最亲密的亲属).
- 为了确定羽毛是否起源于Avemetatarsalia的底部或在Theropoda (恐龙的一组) 内.
- 探索不同起源场景的含义,包括潜在的羽毛损失或丝状附属物的独立进化.
主要方法:
- 对化石证据的分析,包括恐龙和龙的整体部附属物.
- 在已灭绝和现存的种类中对羽毛形态,微观结构和超级结构进行比较研究.
- 整合了形态,发育,生化和语音学数据.
主要成果:
- 化石证据表明,复杂的羽毛进化和飞行羽毛的获得早于鸟类起源.
- 早期和现代羽毛之间存在显著的差异,突出了多种多样的体进化途径.
- "真实"羽毛的确切起源 (阿维梅塔塔萨利亚的底层与Theropoda中的底层) 仍然没有解决.
结论:
- 羽毛的进化比以前理解的要复杂得多,有各种形式和途径.
- 解决羽毛的起源需要进一步调查羽毛和毛,特别是在代表性不足的群体.
- 综合性方法对于全面了解羽毛进化是必不可少的.
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