在一个Silurian大长的 placoderm 骨鱼类的状
Xindong Cui1,2, Matt Friedman3, Yilun Yu2,4
1Key Laboratory of Orogenic Belts and Crustal Evolution, School of Earth and Space Sciences, Peking University, 100871, Beijing, China.
Nature communications
|November 22, 2023
概括
拥有4.25亿年历史的鱼类Entelognathus揭示了对脊椎动物进化的新见解. 它的和棘表明,关键的脊椎动物特征比以前认为的要早.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 脊椎动物动物学 脊椎动物动物学
背景情况:
- 的脊椎动物表现出多样化的皮肤盔甲 (板块和).
- 这些盔甲类型之间的进化过渡不太清楚.
- 具有中间特征的关键化石种类是罕见的.
研究的目的:
- 为了调查Entelognathus的遗传位置和特征.
- 为了澄清的脊椎动物皮肤盔甲和翅膀结构的进化起源.
- 为了了解胞体的早期进化.
主要方法:
- 对一个新发现的,几乎完整的胸前外骨架的分析.
- 与现存和已灭绝的脊椎动物对Entelognathus的和棘进行了比较形态分析.
- 遗传学分析包含了Entelognathus独特的特征组合.
主要成果:
- 恩特洛格纳图斯 (Entelognathus) 拥有大型的状,带有和关节,此前认为它是骨类动物特有的.
- 据报道,Entelognathus中存在尾脊柱,这种脊柱在一些茎状条动物中也存在.
- 这种特征的马赛克挑战了关于脊椎动物特征分布的先前假设.
结论:
- 许多gnathostome的特征,包括类型和翅膀脊柱的存在,可能早于现存的脊椎动物的共同祖先.
- Entelognathus为关键脊椎动物特征的早期进化提供了关键的证据.
- 这项研究完善了我们对椎动物皮肤盔甲和骨特征的进化历史的理解.
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