相关实验视频
Updated: Jun 24, 2026
08:02
Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
Published on: May 7, 2016
最古老的关节骨揭示了马赛克格纳托斯托姆字符
Min Zhu1, Wenjin Zhao, Liantao Jia
1Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology (IVPP), Chinese Academy of Sciences, PO Box 643, Beijing 100044, China. zhumin@ivpp.ac.cn
Nature
|March 28, 2009
概括
来自鲁纪的新近完整的鱼化石揭示了意想不到的特征,揭示了骨类鱼类 (骨类) 和脊椎动物 (骨类) 的早期进化. 这一发现推迟了关键进化分裂的时间表.
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:
- 骨科动物 (骨鱼和四足动物) 的进化可以追溯到鲁纪,但证据仅限于碎片化化石.
- 了解早期的脊椎动物进化需要更完整的化石记录.
研究的目的:
- 为了描述一个新发现的,特别保存的原始鱼类从Silurian时期的Ludlow时代.
- 为了分析化石的后骨,了解早期的骨类和石类进化.
- 为了确定Actinopterygian-sarcopterygian分裂的最低日期.
主要方法:
- 在中国云南发现和挖掘化石.
- 详细的形态分析保存非常好的化石鱼.
- 与已知的基底石和非骨的骨骨学研究进行了比较解剖研究.
主要成果:
- 发现了最古老的近乎完整的格纳托斯托姆,这是来自中国云南的卢德洛的原始鱼.
- 这种化石呈现出原始特征 (胸皮带,中脊柱) 和衍生特征 (巨斑) 的混合体.
- 这种结合支持了先前对像Psarolepis.pis这样的基底石类动物的研究结果.
结论:
- 这种新分类代表了最古老的关节性sarcopterygian,提供了关于osteichthyan起源的关键数据.
- 这些发现表明,actinopterygian-sarcopterygian分裂最晚发生在4.19亿年前.
- 这一发现突显了早期脊椎动物进化的马赛克性质.
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