鸟类的骨盆经历了恐龙祖先的条件
Christopher T Griffin1,2,3, João F Botelho1,2,4, Michael Hanson1,2
1Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA.
Nature
|July 27, 2022
概括
鸟的骨盆发育揭示了在胚胎生长过程中暂时出现的祖先恐龙的特征. 这种进化模式表明鸟类进化中的"终端加法"机制.
科学领域:
- 古生物学
- 发育生物学
- 进化生物学
背景情况:
- 活着的鸟类 (Aves) 呈现出从它们的爬行动物祖先显著的解剖学修饰.
- 鸟类的骨盆在从早期的类动物到现代鸟类的转变过程中发生了重大变化.
- 虽然化石记录记录了进化变化,但基本的发育过程 (本体发生) 不太清楚.
研究的目的:
- 通过胚胎成像来研究鸟类盆腔组织的三维形态发生.
- 为了比较鸟类的骨盆发育与恐龙到鸟类的化石记录.
- 了解鸟类骨盆的发展基础.
主要方法:
- 使用先进的胚胎成像技术在三维检查骨盆组织的发展.
- 进行了定量分析,以比较鸟类的骨盆本体与家族遗传序列.
- 在Archosauria的骨盆内研究了表型共变性.
主要成果:
- 恐龙祖先的骨盆特征 (例如,面向前的阴茎,阴茎"靴") 在早期鸟类胚胎形成过程中被暂时观察到.
- 鸟类的骨盆发育遵循一个产前序列,反映了非鸟类恐龙的进化特征.
- 在骨盆中表现出表型共变性,在阿尔科索里亚中保存,可能解释了祖先状态的保留.
结论:
- 鸟类的盆腔进化很可能是通过"终端添加"发生的,在一个发展序列的末尾添加了新的特征,表达了早期的祖先状态.
- 骨盆中的表型整合表明了进化过程中终端添加的新机制.
- 这项研究强调了研究胚胎发育的重要性,以了解进化过渡和祖先特征的保留.
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