Chemically reinforced conditioned courtship in Drosophila: responses of wild-type and the dunce, amnesiac and don giovanni mutants.

To test the hypothesis that associative learning is the basis for conditioned courtship, male Drosophila melanogaster were paired with virgin females in the presence of quinine, known to be a negative reinforcer in a learning paradigm independent of courtship. Such "experienced" wild-type males failed to court virgin females and remained refractory to them for 1-2 h. But experienced males from the learning-defective strain, dunce, continued to court females at high levels; and experienced males from the retention-defective strain, amnesiac, failed to demonstrate the wild-type refractory period. Finally, males from the don giovanni strain, defective with respect to fertilized-female conditioning, were conditioned by presentation of virgin females and quinine. Courtship-depressing effects of cis-vaccenyl alcohol, which can be recovered from fertilized females, were confirmed, but no evidence for its role as a negative reinforcer of male courtship was obtained.