Habituation, sensitization, and redirection of aggression and feeding behavior in the three-spined stickleback (Gasterosteus aculeatus L.).

In Exp I, 3-spined stickleback males maintained in individual aquaria built nests and defended the entire aquarium as a territory. Adjacent compartments containing another male, a gravid female, or a nongravid female provided a social context within which to study habituation and sensitization of aggression elicited by a conspecific male intruded into S's territory. Typical sensitization–habituation curves were found for all Ss regardless of kind of neighbor. However, behavior redirected as a result of stimulation of the intruded male differed between conditions. Ss with a male neighbor showed increased aggression toward the neighbor; Ss with a gravid female neighbor showed courtship; and Ss with nongravid female showed neither. A 3rd behavior, nest building, showed no difference between conditions. Exp II elicited the same motor response to the intruded stimulus, but the motivational category was changed by eliciting the behavior by presenting live brine shrimp. Aggression did not change during habituation, but the waning predation was redirected to another food-securing behavior, picking at the substrate. Results provide evidence for the important role that social context plays in understanding the redirection of behaviors, a phenomenon predicted from an extension of the dual-process theory of habituation. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)