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坎布里亚纪的冠状化物与遗传学和化石记录一致
Hong Chen1,2,3, Luke A Parry4,5, Jakob Vinther6,7
1Yunnan Key Laboratory for Palaeobiology, Institute of Palaeontology, Yunnan University, Kunming, China.
Nature
|June 13, 2020
概括
一个新的化石多叶,丹尼 (Dannychaeta tucolus),来自早期的坎布里亚时期,提供了关于类动物进化的见解. 这一发现揭示了Annelida属的早期生态和形态多样性.
科学领域:
- 古生物学
- 进化生物学
- 动物学
背景情况:
- 由于分子族系和化石记录的相互矛盾的数据,类动物的早期进化不太清楚.
- 坎布里亚时代的化物化石表明了表观生活方式,与表观学数据形成鲜明对比,这些数据表明了早期分离的状或管状类.
- 马格洛尼科和奥威尼科 (Palaeoannelida) 是所有其他类动物的姐妹群,在生活方式和形态上与坎布里亚分类有很大不同.
研究的目的:
- 描述一个新的化石多基,Dannychaeta tucolus,从坎布里亚早期.
- 分析这一新化石的遗传位置和生态影响.
- 提供早期类动物进化的节奏和多样性的限制.
主要方法:
- 一个新的化石多基的描述,丹尼基 (Dannychaeta tucolus),来自Canglangpu形成.
- 形态分析侧重于前列腺,手掌,胸部,腹部和四肢.
- 植物遗传学分析以确定Dannychaeta在Annelida中的位置.
主要成果:
- 描述了丹尼 (Dannychaeta tucolus) 保存在有机的居住管中,具有形的前,长长的手掌和带有的双脚.
- 丹尼切塔的形态特征与现存的马格龙科有共同之处.
- 遗传学分析将丹尼基亚群置于古类中,作为所有其他类的姐妹群.
结论:
- 丹尼甲 (Dannychaeta tucolus) 是最古老的已知多甲,无疑属于冠状甲.
- 这种化石提供了早期类动物未知的生态和形态多样性的关键证据.
- 这一发现限制了类动物进化的时间表,特别是在状和管状物种中.
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