The function of resilin in honeybee wings

Abstract

The present work aims to reveal morphological characteristics of worker honeybee (Apis mellifera) wings and demonstrate the function of resilin on camber changes during flapping flight. Detailed morphological investigation of the wings showed that different surface characteristics appeared on the dorsal and ventral side of the honeybee wings and the linking structure connecting the forewing and hindwing plays an indispensible role in honeybee flapping flight. Resilin stripes were found on both the dorsal and ventral side of the wings, and resilin patches mostly existed on the ventral side. On the basis of resilin distribution, five flexion lines and three cambered types around the lines of passive deformation of the coupled-wing profile were obtained, which defined the deformation mechanism of the wing along the chord, i.e., concave, flat plate and convex. According to the movie of the high-speed photography from the three orthogonal views for the free flight of honeybees, periodic changes of the coupled-wing profile were acquired and further demonstrated that the deformation mechanism is fundamental domination for variable deformed shapes of the wing profile during flapping flight and especially the flat wing profile achieves nice transition between downstrokes and upstrokes.