The suggestion that caudal pigment spots in fishes can act as deflection marks is tested experimentally. Fish with artificial caudal spots escape predators more often than the same species without spots, but the difference was not significant (0.1 < p < 0.2). However in fish captured, the place on the body where the fish was seized was shifted posteriorly by the presence of a spot (p < 0.01). Although the results are equivocal, they do suggest a possible selective basis for convergence in colour pattern in small characid fishes.