较低的形态差异和肢体尺寸进化的减速接近鸟类的起源
1Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China. wangmin@ivpp.ac.cn.
Nature ecology & evolution
|June 5, 2023
概括
鸟类从恐龙的进化表明肢体的变化. 与预期相反,飞机的飞行方式不同.
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:
- 热足恐龙向鸟类的转变涉及显著的解剖学变化,特别是肢体,这对飞行发展至关重要.
- 了解四肢进化模式是解读早期飞禽类从陆地到飞行的转变的关键.
研究的目的:
- 分析早期鸟类谱系中尾肢体的形态差异和进化速率.
- 研究飞行等进化创新如何影响进化能力和四肢形态.
主要方法:
- 利用原始遗传学比较方法来研究四肢进化.
- 在鸟类干系中检查了形态差异和进化速率的模式.
主要成果:
- 在鸟类起源附近观察到向低差异的转变和减缓的进化速度.
- 确定前肢是导致这种进化约束的主要因素.
- 挑战了主要创新必然加速可变性的观念.
结论:
- 自然选择塑造了早期飞禽类的四肢进化,有利于受约束的前肢.
- 这种约束可能是机动飞行所必不可少的有翅膀的前肢的"蓝图".
- 飞行的进化并没有导致早期鸟类血统的四肢进化能力增加.
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