Abstract
We describe persistent one-way walking of Drosophila melanogaster in a circular arena. Wild-type Canton-S adult flies walked in one direction, counter-clockwise or clockwise, for minutes, whereas white-eyed mutant w1118 changed directions frequently. Computational analysis of loco-motor behavior showed that counter-clockwise walking and clockwise walking were the two main components of locomotion in circular arenas. Genetic analysis revealed that while wild-type genetic background suppressed the number of counter-clockwise and clockwise walks during five minutes of locomotion, the white (w+) gene promoted persistent one-way walking by increasing the maximal duration of one-way walking. These results support a pleiotropic function of w+ in promoting persistent one-way walking in addition to eye pigmentation.