Cruising the rain forest floor: butterfly wing shape evolution and gliding in ground effect

Flight is a key innovation in the evolutionary success of insects and essential to dispersal, territoriality, courtship and oviposition. Wing shape influences flight performance and selection likely acts to maximize performance for conducting essential behaviours that in turn results in evolution of wing shape. As wing shape also contributes to fitness, optimal shapes for particular flight behaviours can be assessed with aerodynamic predictions and placed in an ecomorphological context. Butterflies in the tribe Haeterini (Nymphalidae) are conspicuous members of understory faunas in lowland Neotropical forests. Field observations indicate that the five genera in this clade differ in flight height and behaviour: four use gliding flight at the forest floor level, and one utilizes flapping flight above the forest floor. Nonetheless, the association of ground level gliding flight behaviour and wing shape has never been investigated in this or any other butterfly group. We used landmark-based...飞行是昆虫演化取得成功的关键创新特征，对于昆虫的扩散、领域防御、求偶以及产卵均至关重要。翅形会影响飞行性能，而自然选择很可能会倾向于最大化昆虫完成各类核心行为所需的飞行性能，进而推动翅形的演化。由于翅形同样影响个体适合度，因此可通过空气动力学预测评估特定飞行行为对应的最优翅形，并将其纳入生态形态学的研究框架之中。蛱蝶科（Nymphalidae）埃特里尼蝶族（Haeterini）的蝴蝶是新热带低地森林林下动物群中的醒目类群。野外观察显示，该演化支下的5个属在飞行高度与飞行行为上存在差异：其中4个属在林下层地面开展滑翔飞行，另有1个属则在林地上方进行振翅飞行。然而，无论是该类群还是其他任何蝴蝶类群，目前均未有针对地面滑翔飞行行为与翅形之间关联的相关研究。我们采用基于地标点的...