LIMITS TO VERTEBRATE LOCOMOTOR ENERGETICS SUGGESTED BY HUMMINGBIRDS HOVERING IN HELIOX
LIMITS TO VERTEBRATE LOCOMOTOR ENERGETICS SUGGESTED BY HUMMINGBIRDS HOVERING IN HELIOX
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DOI：
10.1038/377722a0
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发表时间：
1995-10-26
期刊：
影响因子：
64.8
通讯作者：
DUDLEY, R
中科院分区：
文献类型：
--
作者：
CHAI, P;DUDLEY, R
盘旋蜂鸟的耗氧量（1）和肌肉输出功率（2）是脊椎动物中最高的记录。因此，蜂鸟的最大性能接近脊椎动物有氧运动的上限（3）。因为空气密度是空气动力要求（4）的主要决定因素，所以可以使用可变密度的常氧气体混合物（6）非侵入性地操纵悬停飞行性能（5）。在这里，我们表明，在低于海平面空气的一半密度低的空气动力学故障的盘旋红喉蜂鸟的运动能力的限制是明确表示。蜂鸟表现出相当大的功率储备，肌肉质量比功率（假设完美的弹性能量存储）平均从正常空气中的98 W kg（-1）到空气动力学失效前的最大值133 W kg（-1），与此相反可变功率消耗，然而，肌肉效率保持大致恒定在10%。功率输出的调制主要通过改变机翼冲程振幅来实现，在180度附近发生气动故障。
OXYGEN consumption(1) and muscle power output(2) of hovering hummingbirds are among the highest recorded for vertebrates. Maximum performance of hummingbirds thus approaches the upper limits of vertebrate aerobic locomotion(3). Because air density is a major determinant of aerodynamic power requirements(4), hovering flight performances(5) can be manipulated non-invasively using normoxic gas mixtures of variable density(6). Here we show that limits to the locomotor capacity of hovering ruby-throated hummingbirds are unequivocally indicated by aerodynamic failure at low densities less than half that of sea-level air. Hummingbirds demonstrate considerable power reserves, with muscle mass-specific power (assuming perfect elastic energy storage) averaging from 98 W kg(-1) in normal air to a maximum value of 133 W kg(-1) before aerodynamic failure, in contrast to such variable power expenditure, however, muscle efficiency remains approximately constant at 10%. Modulation of power output is attained primarily through variation in wing-stroke amplitude, with aerodynamic failure occurring near 180 degrees.