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新的爬行动物显示恐龙和龙在不同的前体中进化
Rodrigo T Müller1,2, Martín D Ezcurra3, Mauricio S Garcia4,5
1Centro de Apoio à Pesquisa Paleontológica da Quarta Colônia, Universidade Federal de Santa Maria, São João do Polêsine, Brazil. rodrigotmuller@hotmail.com.
Nature
|August 16, 2023
概括
一个新的化石,Venetoraptor gassenae,揭示了早期恐龙前身的猛禽嘴和大爪子,在恐龙的类似特征之前有8000万年. 这一发现突显了鸟类进化的早期形态多样性.
科学领域:
- 古生物学
- 脊椎动物的进化
- 中世爬行动物
背景情况:
- 恐龙和龙在中生代早期表现出显著的多样性和生态创新.
- 这些群体的前身也多样而广泛,但通常缺乏保存良好的骨遗骸,特别是头骨和手.
研究的目的:
- 描述一个新的,保存完好的虫化石, 来自巴西的三叠纪.
- 提供关于早期恐龙和龙前体的头骨形态,生态和进化位置的新见解.
主要方法:
- 部分骨的挖掘和详细解剖分析,包括头骨和手部件.
- 与其他已知的恐龙和龙前体进行比较的解剖分析.
主要成果:
- 威尼托拉普特 (Venetoraptor gassenae) 拥有尖的捕食性和长爪的大手,这表明这些血统中四足动物的强制性丧失.
- 发现前体的形态差异与三叠纪的龙相似,并且比三叠纪的恐龙更大.
结论:
- 恐龙和类动物的"成功"源于在更广泛的生态形态变异范围内的差异性生存.
- 鸟类的形态多样性起源于早期分离的血统,不仅仅是恐龙和类动物出现后.
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