The effect of an androgen inhibitor on behavior and testicular morphology in the stickleback Gasterosteus aculeatus

It is generally held that the decline in courtship which is seen at the beginning of incubation during the reproductive cycle of the male ring dove (Streptopelia risoria) is the result of changes in endocrine secretion rather than changes in response to the external situation. To test this hypothesis, male ring doves proceeding through a cycle with their mates were tested at selected intervals to determine whether there was a decline in courtship behavior in the course of a reproductive cycle. Four conditions were examined. Inexperienced and experienced males were tested with a stimulus female in two situations; once after the mate and nest were removed from the home cage, and once after the mate only was removed. In the former situation the male courted a stimulus female irrespective of the stage of the cycle he had reached with his mate. In the latter situation, as incubation with the mate progressed, males continued to incubate when the stimulus female was introduced. Thus, the male's display of courtship during the reproductive cycle is influenced by the external stimulus situation presented by the female and the nest.