A mutant strain in Drosophila melanogaster that is defective in courtship behavioural cues

Experience-dependent modification of courtship behaviour in Drosophila melanogaster has been previously reported; males that have courted fertilized females thereafter avoid courtship with virgin females for 2–3 h. We report that this modification is dependent upon a behavioural interaction between a courting male and fertilized female. Behavioural comparisons of males of the mutant strain Don Giovanni (dg) and normal males imply that fertilized females release a conditioning cue in response to male courtship. (1) The normal behaviour modifying capacity of fertilized females is dependent upon copulation. Females fertilized by dg do not effectively modify male courtship. (2) dg males are deficient in causing fertilized females to release a conditioning cue; fertilized females which are courted by dg males do not induce modification of behaviour. (3) The behaviour of dg males can be modified if the fertilized females they court have been first courted by normal males. These defects were mapped to the y-cv interval of the X-chromosome.