Sexual conditioning has been demonstrated in a variety of species but it has been most extensively investigated in male Japanese quail. The majority of these studies have used arbitrary conditioned stimuli (CSs), but recent experiments have demonstrated that using ecologically relevant female cues as CSs results in significantly improved male sexual conditioning. The proposed experiments are designed to investigate the extent to which ecologically relevant male cues facilitate the sexual conditioning of females. This ecological approach also is extended to non-traditional ways of measuring conditioned responding. In addition to assessing the effects of sexual conditioning by measuring changes in an animal's CS-directed responding, a more functional approach will measure increases in the efficiency of a subject's interactions with a copulation partner. The ultimate standard of ecological validity by which sexual conditioning studies may be measured is facilitated reproductive success. Sexual conditioning has been shown to improve fertility, but the specific conditioning mechanisms that underlie the effect have not yet been identified. The present experiments are designed to investigate the conditioning parameters that regulate the conditioned fertility effect, the relationship between conditioned sexual behavior and increases in reproductive success, and the extent to which sexual conditioning can compensate for fertility deficits. Unlike most conventional animal learning investigations that lack ecological validity, the present experiments incorporate species typical cues directly into the experimental designs. This ecological approach to investigate ways to accentuate an animal's reproductive success facilitates the application of the experimental findings to situations outside the laboratory that animals may experience in their natural environment. ? ? ?