TIME-SHARING AS A MECHANISM FOR THE CONTROL OF BEHAVIOR SEQUENCES DURING THE COURTSHIP OF THE 3-SPINED STICKLEBACK (GASTEROSTEUS-ACULEATUS)

The male stickleback (Gasterosteus aculeatus) alternates between activities directed towards the female and activities directed towards his nest during courtship. The hypothesis that a time-sharing mechanism can control the allocation of time to these two classes of activities was tested using the double interruption method (McFarland 1974). It was found that either nest or female related behaviours could be dominant, as measured by the behaviour that most frequently followed an interruption. The effect of interrupting subdominant behaviour was related to both the length of the interruption and the distribution of uninterrupted visit lengths. The effect of interrupting dominant behaviour was independent of these factors. Disrupting the nest with snails altered the timing of behaviour only during nest dominant sessions. All these results are consistent with the time-sharing hypothesis. In addition, dominance was found to be related to other behavioural measures of the motivational state of the animal. The relevance of this to the classical 'disinhibition' interpretation of the performance of nest activities is discussed. © 1979.