在已知最早的四足动物前肢中,对比的发育轨迹
Viviane Callier1, Jennifer A Clack, Per E Ahlberg
1University Museum of Zoology Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
Science (New York, N.Y.)
|April 18, 2009
概括
早期的四足动物Ichthyostega和Acanthostega表现出不同的四肢发育. 伊希索斯塔格拉 (Ichthyostega) 的意思是什么
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:
- 伊希索斯泰加和阿坎托斯泰加是早期四足动物的关键.
- 阿坎托斯特加通常被视为更原始的.
- 了解它们的四肢发育为四足动物进化提供了洞察力.
研究的目的:
- 为了研究前肢发育的本体遗传轨迹在Ichthyostega和Acanthostega.
- 为了比较这些早期四足动物和干四足动物之间的肌肉附着模式.
- 为了推断陆地运动和植物遗传关系的差异.
主要方法:
- 从Ichthyostega和Acanthostega发现的新骨材料的分析.
- 在不同本能遗传阶段对皮肌肉附着部位进行比较检查.
- 遗传学分析包括新发现的原始特征.
主要成果:
- Ichthyostega humeri显示了从鱼类类的到四足动物类的肌肉附着模式的发育转变.
- 在整个发育过程中,Acanthostega humeri始终显示四足动物类的肌肉附着模式.
- 新发现的原始特征表明,Ichthyostega在遗传学上可能比Acanthostega更基本.
结论:
- 在其发展过程中,Ichthyostega可能表现出更大的发动机地球化.
- 伊希索斯特加的遗传位置可能需要重新评估,可能比以前想象的更基本.
- 人体遗传数据为了解早期四足动物进化和陆地适应提供了关键证据.
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