Limits to Hummingbird Flight Performance: Ecological and Comparative Perspectives

在动物中对运动表现的限制知之甚少。蜂鸟在飞行过程中为了增强能量能力而进行代谢专门化，因此代表了呼吸，心血管和肌肉系统极端生理设计的主要例子。因此，对蜂鸟飞行的分析可能会揭示脊椎动物（包括人类）运动性能的生物力学和生理学限制。 这项研究将探讨限制不同蜂鸟物种的飞行性能，并将确定潜在的变量的贡献，身体大小，翅膀形态，飞行运动学，空气动力学，和呼吸能量的飞行能力。 蜂鸟的种间比较将包括跨越海拔梯度的悬停飞行性能的研究，由于空气密度和氧气供应的物理变化，对飞行动物提出了特别的空气动力学和生理学挑战。 悬停飞行的分析将通过对蜂鸟在风洞中以不同空速飞行时向前飞行性能的限制进行研究来加强。 悬停和向前飞行的综合结果将得出关于蜂鸟飞行能力的空气动力学和生理学限制的性质的基本结论，并且更一般地将描绘脊椎动物运动生理学的广泛性能限制。

Limits to exercise performance are little understood in animals. Hummingbirds exemplify metabolic specialization for enhanced energetic capacity during flight, and thus represent a prime example of extreme physiological design in respiratory, cardiovascular, and muscular systems. The analysis of hummingbird flight may thus reveal fundamental limits to the biomechanics and physiology of vertebrate locomotor performance, including that of humans. This study will examine limits to flight performance in diverse hummingbird species, and will determine potentially variable contributions of body size, wing morphology, flight kinematics, aerodynamics, and respiratory energetics to flight capacity. Interspecific comparisons of hummingbirds will include studies of hovering flight performance across altitudinal gradients which, because of physical variation in air density and oxygen availability, present particular aerodynamic and physiological challenges to flying animals. Analysis of hovering flight will be augmented by study of limits to forward flight performance carried out on hummingbirds flying at different airspeeds in a wind tunnel. The combined results for hovering and forward flight will yield basic conclusions as to the nature of aerodynamic and physiological constraints on hummingbird flight capacity, and more generally will delineate broad performance limits to vertebrate exercise physiology.