来自北美的非鸟类恐龙提供了关于翅膀起源的洞察力
Darla K Zelenitsky1, François Therrien, Gregory M Erickson
1Department of Geoscience, University of Calgary, Calgary, Alberta T2N 1N4, Canada. dkzeleni@ucalgary.ca
Science (New York, N.Y.)
|November 1, 2012
概括
长着羽毛的恐龙称为ornithomimosaurs,以前不知道有羽毛,显示有丝状羽毛和成人的翅膀结构的证据. 这一发现表明,原始的翅膀早些时候在非曼尼拉普托类热足动物中进化.
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:
- 恐龙中羽毛的进化记录在曼尼拉普托拉斯类热足动物中,但在理解其更广泛的起源方面存在差距.
- 类恐龙 (Ornithomimosaurs) 是一群非类恐龙,以前人们不知道它们是否拥有化石羽毛.
研究的目的:
- 为了研究鸟类类恐龙中羽毛的存在和性质.
- 为了获得关于恐龙羽毛的新见解以及鸟类翅膀的进化起源.
主要方法:
- 从加拿大阿尔伯塔省的上白纪沉积物中化石化Ornithomimus标本的分析.
- 在个体的不同生长阶段检查羽毛结构.
主要成果:
- 化石证据证实了ornithomimus在整个生命阶段都有丝状羽毛覆盖的存在.
- 在成年Ornithomimus标本的前肢上发现了类似翅膀的结构.
- 在成年人中,这些类似翅膀的结构的发展表明了与生殖行为的潜在联系.
结论:
- 羽毛存在于非曼尼拉普托类热足动物中,如鸟类类恐龙,扩大了我们对羽毛分布的理解.
- 原始的翅膀,或它们的前体,在热足动物进化过程中比以前假设的更早地产生,比以前的maniraptoran热足动物更早.
- 这些发现有助于了解鸟类飞行结构和恐龙的早期演变.
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