When insects seek to climb higher in the air, they increase their wing angle by contracting still further these muscles between the wing joints. Fast-frame and stop-motion photographs have shown that during flight, the wings follow an elliptical course and that for each wing's cycle, its angle alters systematically. This variation is caused by the changing movements of the direct muscles and the wings' attachment to the body.
The greatest problem faced by very small insect species during flight is air resistance. For them, sheer air density becomes an obstacle for these creatures that can't be underestimated. Moreover, a restrictive layer around the wing causes the air to cling to the wings, leading to a loss in flight efficiency. In order to be able to overcome that air resistance, flies such as Forcipomya, whose wings are no more than 1 millimeter wide, must beat them 1,000 times a second.