Department of Organismic and Evolutionary Biology, Harvard University, Concord Field Station, 100 Old Causeway Road, Bedford, MA 01730, USA.
Proc Biol Sci. 2013 Mar 27;280(1759):20130531. doi: 10.1098/rspb.2013.0531. Print 2013 May 22.
The effect of wing flexibility on aerodynamic force production has emerged as a central question in insect flight research. However, physical and computational models have yielded conflicting results regarding whether wing deformations enhance or diminish flight forces. By experimentally stiffening the wings of live bumblebees, we demonstrate that wing flexibility affects aerodynamic force production in a natural behavioural context. Bumblebee wings were artificially stiffened in vivo by applying a micro-splint to a single flexible vein joint, and the bees were subjected to load-lifting tests. Bees with stiffened wings showed an 8.6 per cent reduction in maximum vertical aerodynamic force production, which cannot be accounted for by changes in gross wing kinematics, as stroke amplitude and flapping frequency were unchanged. Our results reveal that flexible wing design and the resulting passive deformations enhance vertical force production and load-lifting capacity in bumblebees, locomotory traits with important ecological implications.
翅膀的柔韧性对空气动力产生的影响已成为昆虫飞行研究的核心问题。然而，物理和计算模型在翅膀变形是增强还是减小飞行力方面产生了相互矛盾的结果。通过对活体大黄蜂的翅膀进行实验性的加固，我们证明了翅膀的柔韧性在自然行为环境中会影响空气动力的产生。通过在单个柔性静脉关节上施加微夹板，将大黄蜂的翅膀在体内人为地加固，然后对蜜蜂进行举升测试。翅膀变硬的蜜蜂的最大垂直空气动力产生能力下降了 8.6%，这不能用总翅运动学的变化来解释，因为冲程幅度和拍打频率没有变化。我们的结果表明，在大黄蜂中，柔性机翼的设计和由此产生的被动变形增强了垂直力的产生和举升能力，这是具有重要生态意义的运动特征。
