
近日,一项刊登在PNAS上的研究中,作者发现了蚊子在飞行中与雨滴相撞如何存活下来。飞行器的机翼被设计成能抵御雨对阻力、升力以及失速角的影响,但是雨滴大小的蚊子的身体——它们常常在多雨地区兴旺繁殖——如何设法在飞行中幸免于撞击仍然是一个谜。David Hu及其同事使用高速摄影机记录下了一个丙烯酸笼子里飞行的按蚊在接触到模拟降雨的喷水时的情况。
尽管雨滴的尺寸与蚊子类似,雨滴远远更重,雨滴下的一只蚊子的质量比与一辆轿车车轮下的一个人的质量比相同。然而,这组作者报告说,蚊子的轻量级身体帮助它们从碰撞中幸存下来,导致雨滴几乎没有损失动量,并且在撞击的时候传递了较低的力量。此外,这些蚊子的强壮的外骨骼帮助抵消了撞击的部分力量。然而,靠近地面飞行的蚊子可能面临威胁生命的撞击,这在很大程度上是由于它们倾向于以降落的雨滴的速度撞击地面或者淹死在水滩里。
这组作者说,仍然不清楚蚊子是否能通过侧向飞行或者逆向起飞从而躲过雨滴,但是这些发现可能有助于改进用于执行监视以及搜寻救援任务的昆虫尺寸的飞行机器人的设计。(生物谷Bioon.com)
Mosquitoes survive raindrop collisions by virtue of their low mass
Andrew K. Dickersona, Peter G. Shanklesa, Nihar M. Madhavana, and David L. Hua,b,1
In the study of insect flight, adaptations to complex flight conditions such as wind and rain are poorly understood. Mosquitoes thrive in areas of high humidity and rainfall, in which raindrops can weigh more than 50 times a mosquito. In this combined experimental and theoretical study, we here show that free-flying mosquitoes can survive the high-speed impact of falling raindrops. High-speed videography of those impacts reveals a mechanism for survival: A mosquito’s strong exoskeleton and low mass renders it impervious to falling drops. The mosquito’s low mass causes raindrops to lose little momentum upon impact and so impart correspondingly low forces to the mosquitoes. Our findings demonstrate that small fliers are robust to in-flight perturbations.
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