Conducted 3 separate experiments, with a total of 70 male Bettas and 30 male Siamese fighting fish, in which Bettas were exposed, respectively, to mirror images, a variety of conspecifics, and to future opponents, prior to combat with unexposed Ss. Threat display to mirror images and to live opponents habituated significantly, but the outcomes of dominance-subordinance tests were not significantly affected by prior exposure to any of the threat-eliciting stimuli. Results are discussed in terms of stimulus and response specificity and possible chemical suppression of agonistic behavior. (20 ref) (PsycINFO Database Record (c) 2004 APA, all rights reserved)