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Updated: Jun 27, 2025

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Creating Avian Forebrain Chimeras to Assess Facial Development
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使用你的头 - 骨方向在类动物中的方向
1Royal Tyrrell Museum of Palaeontology, Drumheller, AB, Canada. don.henderson@gov.ab.ca.
Die Naturwissenschaften
|May 7, 2024
概括
恐龙的头部和顶可能控制着飞行方向盘. 它们的大小创造了与身体惯性相对应的转动时刻,这表明它们具有功能性空气动力学作用.
科学领域:
- 古生物学的古生物学
- 空气动力学 航空动力学
- 生物力学 生物力学
背景情况:
- 龙,灭绝的飞行爬行动物,通常拥有大头和精心设计的峰.
- 这些头骨结构在飞行过程中的空气动力学影响尚未完全理解.
研究的目的:
- 为了研究超大尺寸的龙头和在飞行期间控制横向身体运动的假设.
- 为了确定头 - 子转动时刻与龙全身旋转惯性之间的关系.
主要方法:
- 为分析质量分布,创建了18种类动物 (8种类动物,10种类动物) 的数字模型.
- 转时刻是根据头部/顶部侧面面积,空气动力学升力和估计的飞行速度 (根据身体质量) 计算的.
- 从整个身体的3D质量分布计算了旋转惯性,包括四肢和飞行膜.
主要成果:
- 观察到,头+的计算转动时刻与全身围绕垂直轴的旋转惯性之间存在很强的相关性.
- 这种对应性在研究的两大龙群体 (rhamphorhynchoids和pterodactyloids) 都是一致的.
- 这些发现支持了形态与飞行控制机制之间的功能联系.
结论:
- 这项研究提供了证据,证明大型龙头和在飞行期间管理横向稳定性和转向方面发挥了重要作用.
- 这些结果为修订两种龙的生命恢复提供了信息,并建议另外两种龙的飞行速度降低.
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