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来自中国的一只装甲的坎布里亚龙足动物,有关节动物类的附属物
Jianni Liu1, Michael Steiner, Jason A Dunlop
1Early Life Institute, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China. liujianni@126.com
Nature
|February 26, 2011
概括
一个新的坎布里亚化石,Diania cactiformis,揭示了装甲的附属物,这表明四肢硬化在关节动物进化过程中先于身体硬化. 这一发现揭示了早期的元动物起源.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 坎布里亚生物群的生物群
背景情况:
- 坎布里亚化石Lagerstätten提供了关于早期元动物起源的见解.
- 球形虫,或"有腿的虫",是了解Onychophora,Tardigrada和Arthropoda进化的关键.
研究的目的:
- 为了描述Diania cactiformis,这是一个来自成江化石仓库的新型"装甲"lobopodian.
- 调查D. cactiformis. 的遗传位置和进化影响.
主要方法:
- 来自成江化石仓库的化石标本的描述.
- 遗传学分析以确定Diania cactiformis.的进化关系.
主要成果:
- 迪亚尼亚仙人掌具有坚固的,可能是硬化,并有关节的附属物,更接近于以前已知的lobopodians的关节动物四肢形态.
- 遗传学分析将D. cactiformis置于Arthropoda.附近的衍生位置.
- 这些发现表明,关节化 (四肢硬化) 可能在关节化 (身体硬化) 之前发生.
结论:
- 迪亚尼亚仙人掌 (Diania cactiformis) 代表了一个关键的过渡形式,接近真正的节肢动物的起源.
- 这项研究支持了 lobopodians 是一个表现出不同程度的关节化的一种类型群的假设.
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