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埃克迪索动物体型图的早期演变
Deng Wang1, Yaqin Qiang2, Junfeng Guo2
1State Key Laboratory of Continental Dynamics, Shaanxi Key Laboratory of Early Life & Environments and Department of Geology, Northwest University, Xi'an, China.
eLife
|July 8, 2024
概括
发现贝雷特拉·斯皮诺萨 (Beretella spinosa),一个袋状的坎布里亚动物,挑战了祖先生态动物 (动物) 是长长的观念. 这一发现表明,早期的ecdysozoans可能具有非虫类的身体计划.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 动物系统学 动物系统学
背景情况:
- 埃克迪索动物 (Ecdysozoans) 是一个主要的转动物群体,表现出多样化的身体计划.
- 埃克迪索动物的祖先体型图,特别是其潜在的虫状 (延长,管状) 性质,仍然是科学辩论的主题.
研究的目的:
- 描述一个新的化石物种,Beretella spinosa,来自最低的坎布里亚.
- 调查贝雷特拉·斯皮诺萨 (Beretella spinosa) 和萨科里图斯·冠状病毒 (Saccorhytus coronarius) 在Ecdysozoa中的遗传位置.
- 根据新的化石证据,重新评估Ecdysozoa祖先的身体计划.
主要方法:
- 发现贝雷特拉·斯皮诺萨 (Beretella spinosa gen. et sp.) 的化石和形态描述. 在新的一年里.
- 植物遗传学分析,包括形态学数据.
- 与已知的坎布里亚动物和现存的ecdysozoans相比较的解剖学.
主要成果:
- 描述Beretella spinosa,一个微小 (3毫米) 的坎布里亚生态生态动物,有袋状的身体,单一的开口,和刺的装饰.
- 遗传学分析将Beretella spinosa和Saccorhytus coronarius作为所有其他Ecdysozoa的姐妹群 (Saccorhytida).
- 萨科里蒂达群体代表了早期的脱落,这表明祖先的ecdysozoans不一定是虫.
结论:
- 包括Beretella spinosa在内的Saccorhytida血统为早期的生态动物进化提供了关键的见解.
- 这些发现挑战了长期以来关于虫形祖先生态动物体型计划的假设.
- 早期的ecdysozoans可能拥有多样化的,非虫类的身体架构.
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