最古老的关节性孔德里希提亚人来自早期德纪时期
Randall F Miller1, Richard Cloutier, Susan Turner
1Steinhammer Palaeontology Laboratory, New Brunswick Museum, Saint John, New Brunswick E2K 1E5, Canada. millerrf@nb.aibn.com
Nature
|October 3, 2003
概括
发现了一种4亿9千万年前的关节鱼,Doliodus problematicus,为早期的鱼提供了洞察力. 这种化石揭示了配对的胸翼脊柱,这是以前在软骨鱼类中未知的特征.
科学领域:
- 古生物学的古生物学
- 脊椎动物的进化 脊椎动物的进化
- 鱼类学 鱼类学 鱼类学
背景情况:
- 包括鱼在内的孔德里希提亚人有可追溯到奥尔多维纪晚期的化石记录.
- 已知最古老的关节鱼遗骸来自早期德纪.
- 以前,Doliodus problematicus只从单独的牙中知道,它的分类受到争论.
研究的目的:
- 报道发现了一个保存得非常完善的关鱼化石.
- 为了阐明早期的进化和chondrichthyans和基底脊椎动物的相互关系.
- 为了调查Doliodus problematicus的分类学地位.
主要方法:
- 化石载体层的地质约会.
- 关节化石的详细形态分析,包括牙,脑和翅膀结构.
- 与其他早期脊椎动物化石进行比较的解剖学研究.
主要成果:
- 发现了一种4亿9千万年前的关节鱼,Doliodus problematicus,来自加拿大早期的文纪.
- 这种标本是现场牙家族最古老的鱼,也是发现的最古老的孔德里希脑之一.
- 化石展出了配对的胸翅膀脊柱,这是软骨鱼类的新奇特征.
结论:
- 问题鱼 (Doliodus problematicus) 代表了早期鱼进化中的一个关键的过渡形式.
- 配对的胸翼脊柱的存在挑战了以前对早期德里希特人解剖学的理解.
- 这一发现增强了我们对基底脊椎动物多样化的知识.
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