 When the target fly is another male, the two males may oscillate sideways while both try to track the other fly; they may also signal to other male fly that they are of the same sex by meeting them head on in flight.Males' tracking behavior in flight potentially serves as a function for mating, as such behavior often ends with a sharp dart towards the target fly after it has settled.During those rapid movements, the male fly maintains an acceleration rate at about 500 cm/s2 until just before it lands and is prepared for copulation.