仅仅诱导功率缩放无法解释的巨大化
Olaf Ellers1, Caleb M Gordon1,2, Max T Hukill1
1Department of Biology, Bowdoin College, Brunswick, ME 04011, USA.
Integrative and comparative biology
|June 4, 2024
概括
巨型灭绝的可能是由于肌肉力量的扩大而飞行,而不仅仅是更高的氧气. 这项研究解释了这些古老的昆虫是如何达到它们巨大的尺寸和飞行能力的.
科学领域:
- 古生物动物学古生物学.
- 昆虫飞行的生物力学
- 进化生物学是进化的生物学.
背景情况:
- 古生代的天空上出现了灭绝的,有些翅膀的跨度远远超过了现代龙.
- 以前的假设将它们的大小归因于大气氧气和空气密度的增加.
- 了解这些古老的昆虫的飞行能力是了解古老生态系统的关键.
研究的目的:
- 为了评估大气中较高的氧气水平使较大的飞行成为可能的假设.
- 为了确定空气密度和氧气度对昆虫飞行功率的贡献.
- 探索对已灭绝的类动物的大小的替代解释.
主要方法:
- 执行器盘理论的应用,以估计飞行的诱导功率需求.
- 计算考虑与飞行员大小和大气条件相关的同位数和同位数.
- 在更密集的空气和飞行肌肉功率扩展中分析形和寄生虫功率.
主要成果:
- 更高的空气密度仅仅在一定程度上降低了诱导功率,仅支持稍大的飞行器.
- 即使氧气较高,计算的飞大小增加也有限 (1.19-1.22倍现存的).
- 较高的氧气和减少的诱导功率并不能完全解释的3.4倍大小;肌肉功率的扩大是一个更合理的因素.
结论:
- 大气中较高的氧气和空气密度不足以解释的巨大尺寸.
- 飞行肌肉功率的缩放,可能具有质量独立输出 (质量^0),是一个更有可能的解释.
- 为了验证这些发现,还需要进一步对Odonate飞行肌肉功率缩放的实验研究.
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