已知最小的非鸟类类热足类恐龙是已知最小的非鸟类热足类恐龙
1The Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, People's Republic of China. xxu@midwest.com.cn
Nature
|December 29, 2000
概括
一种新的龙类恐龙,Microraptor zhaoianus,是第一个比Archaeopteryx更小的成熟的非鸟类恐龙. 这一发现弥合了早期鸟类和它们的热足类亲属之间的尺寸差距.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 脊椎动物动物学 脊椎动物动物学
背景情况:
- 非鸟类恐龙通常是中型到大型的,成熟的标本超过了Archaeopteryx的大小.
- 从历史上看,最早的鸟类和它们最接近的非鸟类类类类动物之间存在着大小差异.
研究的目的:
- 为了报道发现Microraptor zhaoianus,一种新的龙类恐龙.
- 为了解决早期鸟类和非鸟类类类动物之间的尺寸差异.
- 为鸟类的形态和生态转型提供见解.
主要方法:
- 来自中国白纪早期的Jiufotang形成的Microraptor zhaoianus的化石发现和分析.
- 骨特征的比较形态分析,包括牙,腰椎,尾椎和足部结构.
- 与Archaeopteryx和树木鸟类的比较.
主要成果:
- 微龙 (Microraptor zhaoianus) 是第一个成熟的非鸟类恐龙,被发现比Archaeopteryx.x更小.
- 独特的龙类动物特征包括类似鸟类的牙,类似拉霍纳维斯的骨和较少的尾椎.
- 几乎完整的脚表现出树木鸟类的特征,例如距离位置的数字I,细长的回归爪子和延长的前最后一个手环.
结论:
- 发现Microraptor zhaoianus消除了早期鸟类和它们最近的非鸟类亲属之间的尺寸差距.
- 微猛龙 (Microraptor zhaoianus) 的形态特征为了解转变为鸟类提供了关键数据.
- 脚的树木适应提供了对鸟类类脚恐龙古生态的新见解.
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