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Simon Conway Morris¹, Jean-Bernard Caron²

¹Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK.

|June 12, 2014

概括

新的Metaspriggina化石揭示了它是一个基底脊椎动物,具有关键特征,如记号和相机类型的眼睛. 这一发现揭示了早期鱼类进化和原始无脊椎动物的世界性质.

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:

早期的鱼类进化知识依赖于来自中国南方低坎布里亚时期的罕见软体化石.
早期脊椎动物特征和关系的解释往往是有争议的,因为有限的比较材料.

研究的目的:

使用来自伯吉斯页岩和其他坎布里亚期沉积物的新化石材料,重新描述Metaspriggina.
为了澄清早期脊椎动物中Metaspriggina的遗传位置和原始特征.

主要方法:

基于新的,保存良好的化石标本,对Metaspriggina进行了详细的重新描述.
遗传学分析以确定Metaspriggina.的进化关系.

主要成果:

梅塔斯普里吉纳表现出明确的脊椎动物特征,包括一个记号带,相机类型的眼睛,W形肌体和尾.
遗传学分析将Metaspriggina定位为基底脊椎动物,与江分类物种如海科伊希斯和Myllokunmingia密切相关.
两部分分支条表明原始的安排,外的位置可能是祖先的脊椎动物特征.

结论:

Metaspriggina提供了对早期没有的脊椎动物的形态和演变的关键见解.
原始鱼群在低中坎布里亚时期 (系列2-3) 是世界性的.
该研究改进了对原始脊椎动物枝状形态和状结构的理解.

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