CAN IMITATION IN PIGEONS BE EXPLAINED BY LOCAL ENHANCEMENT TOGETHER WITH TRIAL-AND-ERROR LEARNING

Zentall, Sutton, and Sherburne (1996) reported that pigeons observing a conspecific demonstrator either step on or peck at a treadle to obta in food subsequently showed a significant tendency to manipulate the t readle as had their demonstrator. Zentall et al. suggested this findin g showed observer pigeons had learned by imitation to peck at or step on the treadle. However, the same result might have been obtained if p igeons had learned to step on the treadle by trial and error, and pige ons exposed to a treadle-pecking demonstrator had come to peck at the treadle as a result of nonimitative social-learning processes such as local enhancement or contagion. Here, we report the results for two co ntrol groups, showing that pigeons do not learn to step on or peck at a treadle for food reward unless they observe a relevant demonstrator. These results considerably strengthen the original conclusion. Future research using the two-action method to demonstrate imitative learnin g should include similar controls.