长足类恐龙的尾部驱动水中运动
Nizar Ibrahim1, Simone Maganuco2,3, Cristiano Dal Sasso3
1Department of Biology, University of Detroit Mercy, Detroit, MI, USA. ibrahini@udmercy.edu.
Nature
|May 8, 2020
概括
这种巨型热足动物拥有独特的,类似的尾巴, 提供了水中驱动力的强有力的证据. 这一发现挑战了关于恐龙息地的先前假设,
科学领域:
- 古生物学
- 脊椎动物学
- 生物力学
背景情况:
- 在历史上,非鸟类恐龙被认为是陆地动物.
- 以前关于半水生恐龙的理论,特别是关于螺旋龙的理论,仍然存在争议.
- 斯皮诺萨鲁斯 (Spinosaurus aegyptiacus) 是一个大白时期的类动物,表现出各种适应性,表明它是一种食鱼,可能是水生生物.
研究的目的:
- 提供一个明确的证据, 在水中推进结构在Spinosaurus aegyptiacus.
- 为了研究斯宾诺萨鲁斯独特的尾巴形态的生物力学功能.
- 为了比较Spinosaurus尾巴的推进效率与陆地和现存的水生脊椎动物.
主要方法:
- 分析Spinosaurus aegyptiacus独特的尾巴形态,其特征是高大的神经脊柱和长长的支柱.
- 使用机器人动装置测量由物理尾部模型产生的波动力.
- 脊椎动物尾巴模型,陆地恐龙尾巴和现存的水生脊椎动物尾巴之间的推力和效率的比较分析.
主要成果:
- 斯皮诺萨鲁斯 (Spinosaurus aegyptiacus) 拥有独特的,类似翅膀的尾巴结构,能够进行广泛的横向运动.
- 与陆地恐龙的尾巴相比,Spinosaurus的尾巴形状在水中产生了更大的推进力和效率.
- 斯皮诺萨鲁斯尾巴的性能指标与使用垂直扩展尾巴游泳的现存水生脊椎动物相似.
结论:
- 这种独特的尾巴可以作为水中有效的推进器官.
- 这些发现支持斯宾诺鱼的半水生生活方式,并表明恐龙更广泛地侵入水生环境.
- 水生适应,虽然不那么明显,但也存在于其他螺旋类物种中,这表明这个类中的生态转变很大.
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