TyrR^Gal4 homozygous adult males display strong increase in male-male courtship - both toward other males of the same genotype (multiple males chase each other and form chains of courting males) and toward wild-type in single pair trials. The gender preference of TyrR^Gal4 males toward either decapitated wild-type male/female targets or toward live fru^P1.LexA/fru^4-40 male (these males do not court females) and wild-type female in choice assays is not changed compared to controls and strongly biased for females. However, when presented with a fru^P1.LexA/fru^4-40 male alone, TyrR^Gal4 males show strong courtship response to these males as well. Paired with a virgin wild-type female, TyrR^Gal4 males display same courtship initiation latencies and copulation durations as controls and they also show decrease (rather than increase) in aggression and locomotion, suggesting no general increase in arousal. TyrR^Gal4 males display nearly maximal courtship indices toward females regardless of their age - unlike the controls that court mid-aged females more intensely than very young or older ones. TyrR^Gal4 homozygote females exhibit normal post-mating behaviors (decreased receptivity and remating and increased egg laying).