最原始的骨族人的脑袋?
A M Basden1, G C Young, M I Coates
1Centre for Ecostratigraphy and Palaeobiology, Department of Earth and Planetary Sciences, Macquarie University, New South Wales, Australia. abasden@laurel.ocs.mq.edu.au
Nature
|January 26, 2000
概括
在澳大利亚发现的4亿年前的化石脑袋揭示了早期骨鱼 (骨类) 的原始特征. 这一发现为光鱼 (actinopterygians) 和所有现代骨鱼群的进化起源提供了新的见解.
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:
- 骨科动物 (骨鱼) 代表了最多样化的脊椎动物群体,但它们的进化起源仍然不清楚.
- 脊椎动物中最成功的群体 - - 鱼类 (Actinopterygians) 首次出现在纪晚期的化石记录中,但在纪晚期之前人们对其了解甚微.
研究的目的:
- 报告发现最古老和最原始的Actinopterygian类骨类脑袋.
- 提供对现代骨类群体进化辐射附近的解剖条件的新见解.
主要方法:
- 从澳大利亚东南部的4亿年前的石灰岩中发现和分析一块化石骨类脑袋.
- 与其他早期骨类动物进行比较解剖分析,例如Psarolepis.
主要成果:
- 已知最古老的Actinopterygian-like osteichthyan脑被发现,可以追溯到4亿年前.
- 该标本表现出以前未经记录的原始特征,包括为软骨眼的开口.
- 这一发现为类似年龄的化石提供了关键的对应物,如Psarolepis,突出了对比的解剖特征.
结论:
- 新的化石脑袋提供了对骨质动物早期进化的独特见解.
- 这个标本的不同寻常的解剖学挑战了以前对早期脊椎动物进化的理解.
- 这一发现有助于重建现代骨鱼群的主要辐射前的解剖条件.
相关概念视频
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01:14Cranial Bones: Superior and Posterior View
The superior view of the cranium shows the frontal and paired parietal bones.
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01:27Cranial Bones: Lateral View
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01:22Sutures of the Skull
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01:18Anatomy of the Brain: Ventricles
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