placoderm 中的极端下延长反映了脊椎动物早期进化中的高度差异和模块化
Melina Jobbins1, Martin Rücklin2,3, Marcelo R Sánchez Villagra1
1Department of Palaeontology, University of Zurich, Karl-Schmid-Strasse 4, 8004 Zurich, Switzerland.
Royal Society open science
|February 1, 2024
概括
发现*Alienacanthus malkowskii*,一个古老的装甲鱼,揭示了最古老的已知的脊椎动物与极端的延长. 这一发现扩大了我们对早期脊椎动物多样性和食策略的理解.
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:
- 是一种基本的脊椎动物创新,对于理解早期脊椎动物进化至关重要.
- 体动物,最早的脊椎动物,提供了关于食机制和结构多样化的见解.
- 的模块化,以不成比例的长度为例,是一个重要的进化特征.
研究的目的:
- 为了描述*Alienacanthus malkowskii*独特的形态,一个关节状皮.
- 建立已知最古老的脊椎动物极端下延伸和模块化的记录.
- 为了推断*Alienacanthus malkowskii*在早期的体辐射中的食策略和生态作用.
主要方法:
- 从摩洛哥和波兰的Famennian沉积物中发现的*Alienacanthus malkowskii*的化石分析.
- 元素和牙的比较形态.
- 基于骨特征的遗传学和功能解释.
主要成果:
- 马尔科夫斯基 (Alienacanthus malkowskii) 的下长度是其头骨长度的两倍,代表了极端的下延长.
- 脊椎动物中这种显著的模块化的最古老的已知实例.
- 独特的牙与尖的,复发的牙之前的闭塞表明捕获猎物的功能.
- 一种独特的关闭机制,此前未曾在白皮动物中观察到.
结论:
- *Alienacanthus malkowskii* 在早期的脊椎动物中代表着一个重要的进化新奇.
- 这一发现扩大了已知的arthrodire placoderms的形态和生态多样性.
- 独特的下结构表明了专门的掠食性适应,丰富了我们对德纪生态系统的理解.
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