一种原始的鱼类接近四足动物和肺鱼的共同祖先
1Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, China. zhumin@ht.rol.cn.net
Nature
|August 16, 2002
概括
一种新的化石鱼,Styloichthys changae,揭示了早期叶片鱼的关键特征. 这一发现有助于澄清四足动物和肺鱼之间的进化分裂.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 比较解剖学的比较解剖学
背景情况:
- 在sarcopterygians (叶片鱼) 之间的进化关系,特别是四足动物,肺鱼和鱼,仍在争论中.
- 遗传学研究表明四足动物与肺鱼的关系比鱼更为密切.
- 化石记录中存在一个空白,该空白是代表四足动物和肺鱼的共同祖先的分类.
研究的目的:
- 为了描述一个新的化石sarcopterygian,Styloichthys changae gen. 和sp. 在新的一年里.
- 为了调查Styloichthys changae的遗传位置.
- 为了阐明四足形和双形形系的早期分歧.
主要方法:
- 一个新发现的化石的描述古生物学.
- 比较形态学分析.比较形态学分析.
- 基于化石证据的族系学分类.
主要成果:
- 斯泰洛伊希斯 (Styloichthys changae) 拥有独特的原始和衍生字符组合,包括一个眼.
- 这种化石弥合了早期 sarcopterygians 和基底四足形态动物/二足形态动物之间的形态差距.
- 在Styloichthys的字符组合接近于四足动物和肺鱼的祖先的预期.
结论:
- 斯泰洛伊希斯·代 (Styloichthys changae) 提供了对萨科普特里吉亚动物早期进化的关键见解.
- 这一发现有助于理解四足动物和肺鱼的分歧.
- 它有助于重建在这个关键的进化过渡期间的角色获取序列.
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