来自中国南方低纪的状
Plamen S Andreev1,2, Ivan J Sansom3, Qiang Li1,2
1Research Center of Natural History and Culture, Qujing Normal University, Qujing, China.
Nature
|September 28, 2022
概括
化石发现揭示了Fanjingshania renovata,一个来自中国的早期软骨鱼,早于其他脊椎动物. 这种古老的状动物表现出独特的特征,挑战传统的分类,支持早期的状脊椎动物进化.
科学领域:
- 古生物学与进化生物学
- 脊椎动物古生物学
- 鱼类的演变
背景情况:
- 现代的软骨鱼 (chondrichthyans) 和骨鱼 (osteichthyans) 具有不同的骨特征和发育.
- 之前发现的纪和纪脊椎动物已经模糊了早期骨类动物,类动物和它们的祖先之间的界限.
- 和骨之间的进化分裂是古老的,但过渡期化石是了解早期脊椎动物多样化的关键.
研究的目的:
- 描述一个新的chondrichthyan化石,Fanjingshania翻新,从中国的低纪.
- 分析Fanjingshania的骨解剖学,包括皮肤板,和棘.
- 为了研究Fanjingshania独特的原始和衍生特征的进化含义,
主要方法:
- 化石挖掘和制备Fanjingshania renovata的遗骸 (皮肤板,,棘).
- 对Fanjingshania的骨特征进行比较的解剖学分析,与其他化石和现代的氏体和骨体.
- 组织学检查,以确定脊柱和脱机制中存在或缺少臭虫组织.
主要成果:
- Fanjingshania renovata的皮肤肩带板和翅膀脊柱类似于干状条动物 (气候类"acanthodians").
- 独特的是,Fanjingshania 呈现出类似骨类的吸收性脱落,并且其脊椎中缺乏臭性组织.
- 这些特征表明,Fanjingshania在常规定义的acanthodians中获得了独立的特征.
结论:
- 发现Fanjingshania renovata提供了一个强有力的证据,证明了早期的脊椎动物的辐射.
- 金斯哈尼亚独特的解剖学挑战了早期的孔德里希亚人与骨科动物之间的传统区别.
- 这种化石增加了越来越多的类型,需要对低德纪之前的早期脊椎动物多样化的理解进行修订.
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