斯克莱罗莫克卢斯和类动物的早期进化
Davide Foffa1,2,3, Emma M Dunne4,5, Sterling J Nesbitt6
1Department of Natural Sciences, National Museums Scotland, Edinburgh, UK. d.foffa@nms.ac.uk.
Nature
|October 5, 2022
概括
这项研究揭示了一种古老的爬行动物 - - 斯克勒罗莫克卢斯泰洛里 (Scleromochlus taylori), 这一发现有助于弥合了解早期龙起源的差距.
科学领域:
- 古生物学
- 脊椎动物的进化
- 中生代生态系统
背景情况:
- 龙是第一个实现动力飞行的脊椎动物,主导了中生代生态系统.
- 由于它们与它们最亲密的亲属Lagerpetidae之间存在很大的差距,因此人们对类的早期进化和起源的了解仍然很少.
- 一种保存不良的爬行动物,一直与龙有争议.
研究的目的:
- 使用微计算机断层扫描提供精确的整个骨重建.
- 修订Scleromochlus的诊断并澄清它的遗传位置.
- 了解类动物及其近亲的进化起源.
主要方法:
- 微型计算机断层扫描 (微型CT) 斯克莱罗莫克卢斯泰洛里化石.
- 详细的解剖分析和整体骨重建.
- 植物遗传学分析以确定Pterosauromorpha和Avemetatarsalia中的进化关系.
主要成果:
- 这项研究提供了第一个精确的全骨架重建和修订的诊断.
- 斯克勒罗莫克卢斯泰洛里被确定为Pterosauromorpha (类类动物+类动物) 的近亲.
- 斯克莱罗莫克卢斯的解剖学与类动物有相似之处,并保留了阿维梅塔萨利亚的原始特征,这表明早期的类动物是从小型的类祖先进化而来的.
结论:
- 斯克莱罗莫克卢斯泰洛里是了解类动物起源和早期类动物进化的关键分类.
- 这些发现支持了类从小的,可能是双脚的,生活在地面上的祖先进化而来的假设.
- 这项研究显著提升了我们对脊椎动物飞行进化途径的了解.
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