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最早的龙类恐龙来自南美洲的热足动物
Peter J Makovicky1, Sebastián Apesteguía, Federico L Agnolín
1Department of Geology, The Field Museum, 1400 South Lake Shore Drive, Chicago, Illinois 60605, USA.
Nature
|October 14, 2005
概括
早期的马尼拉普托拉恐龙,包括龙类恐龙,可能起源于冈德瓦纳. 一个新的南美化石提供了独特的Gondwanan血统的证据,可以追溯到大陆分离之前.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 恐龙古生物学 恐龙古生物学
背景情况:
- 曼尼拉普托拉 (鸟类和爪恐龙) 的进化历史主要来自北半球.
- 以前从冈德瓦纳发现的马尼拉普托拉化石是不完整的,他们的亲缘关系仍在争论中.
研究的目的:
- 描述一个新的,保存良好的,来自南美洲的龙类恐龙.
- 为了研究Maniraptora的早期进化和冈多瓦分布.
- 为了提供一个Gondwanan血统在大陆分离之前的证据.
主要方法:
- 一个近乎完整的化石标本的描述.
- 遗传学分析以确定进化关系.
- 古生物地理评估德罗玛类的分布.
主要成果:
- 发现了南美最完整和最早的Maniraptora.
- 鉴定了一种独特的冈多瓦龙马类动物血统.
- 有证据表明,这个血统起源于庞盖亚超大陆解体之前.
结论:
- 这一发现挑战了以前对Maniraptora分布的理解.
- 它支持古董起源的冈多瓦龙马类动物血统的存在.
- 这些发现对重建恐龙进化和生物地理学有重大意义.
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