在非鸟类恐龙和现存爬行动物中的表皮尺度生长,度和功能
Nathan James Enriquez1, Nicolás E Campione1, Christophe Hendrickx2,3
1School of Environmental and Rural Science, University of New England, Armidale, New South Wales, Australia.
Journal of anatomy
|March 19, 2025
概括
恐龙的尺度形状在成长过程中保持一致,这表明非适应性功能而不是在交配中的角色. 这种形态停滞的模式也在研究的现存爬行动物中观察到.
科学领域:
- 古生物学的古生物学
- 类学 类学 类学
- 进化生物学 进化生物学
背景情况:
- 类动物的表皮具有不同的生物功能,其形状和大小受到影响.
- 规模形态的与生长相关的变化可能表明青少年与成年个体的不同功能,特别是在交配相互作用中.
- 这种发育模式在现存的爬行动物和非鸟类恐龙中未得到充分探索,限制了功能解释.
研究的目的:
- 调查的生长和形态变化从幼年到成年阶段的鸟类形虫Chasmosaurus belli和形虫Prosaurolophus maximus.
- 将非鸟类恐龙的尺度生长模式与八种现存的爬行动物物种 (Crocodylidae, Scincidae, Elapidae, Pythonidae) 的尺度生长模式进行比较.
- 确定在生长过程中尺度形态的变化是否支持适应性功能,如交配,或反映非适应性过程.
主要方法:
- 在Chasmosaurus belli和Prosaurolophus maximus的青少年和成年标本之间对尺度形态的比较分析.
- 评估了8种现存的爬行动物物种的尺生长和度,这些爬行动物种代表着不同的生态.
- 测量尺度长度和宽度变化的统计评估,以测试异位测量和异位测量.
主要成果:
- 在研究的两种恐龙种群中,尺度形状在增长阶段中基本保持一致.
- 虽然Chasmosaurus belli的尺度宽度增加了,但尺度长度的变化并没有拒绝同度.
- 现存的爬行动物在成长过程中也在很大程度上保留了尺度形状,由于比例的变化,大多数动物在某些身体部位表现出正等量.
结论:
- 在Chasmosaurus belli和Prosaurolophus maximus中观察到的尺度形态变化不支持在交配相互作用中的作用,这表明大多是非适应性的尺寸变化.
- 在研究的非鸟类恐龙中,尺度形状在整个成长过程中表现出形态静止.
- 恐龙的尺度增长模式与现存的爬行动物基本一致,突出了保存的发育过程.
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