Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA.
J Exp Biol. 2013 Feb 15;216(Pt 4):641-55. doi: 10.1242/jeb.077453.
Visually guided collision avoidance is of paramount importance in flight, for instance to allow escape from potential predators. Yet, little is known about the types of collision-avoidance behaviors that may be generated by flying animals in response to an impending visual threat. We studied the behavior of minimally restrained locusts flying in a wind tunnel as they were subjected to looming stimuli presented to the side of the animal, simulating the approach of an object on a collision course. Using high-speed movie recordings, we observed a wide variety of collision-avoidance behaviors including climbs and dives away from - but also towards - the stimulus. In a more restrained setting, we were able to relate kinematic parameters of the flapping wings with yaw changes in the trajectory of the animal. Asymmetric wing flapping was most strongly correlated with changes in yaw, but we also observed a substantial effect of wing deformations. Additionally, the effect of wing deformations on yaw was relatively independent of that of wing asymmetries. Thus, flying locusts exhibit a rich range of collision-avoidance behaviors that depend on several distinct aerodynamic characteristics of wing flapping flight.
在飞行中，视觉引导的避碰至关重要，例如可以让动物躲避潜在的捕食者。然而，对于飞行动物在面临即将到来的视觉威胁时可能产生的避碰行为类型，我们知之甚少。我们在风洞中研究了最小约束的蝗虫的行为，当它们受到模拟物体碰撞路径的侧面逼近的突现刺激时，它们在飞行中。使用高速电影记录，我们观察到各种各样的避碰行为，包括远离但也朝向刺激的爬升和俯冲。在更受约束的环境中，我们能够将翅膀拍打运动的运动学参数与动物轨迹的偏航变化联系起来。不对称的翅膀拍打与偏航的变化最密切相关，但我们也观察到翅膀变形的显著影响。此外，翅膀变形对偏航的影响相对独立于翅膀不对称的影响。因此，飞行蝗虫表现出丰富的避碰行为，这些行为依赖于翅膀拍打飞行的几个不同的空气动力学特征。
