Symmetry : Can pigeons conceptualize it?

Abstract

Pigeons were taught to distinguish a series of 30 bilaterally symmetric and asymmetric visual patterns with an operant simultaneous discrimination procedure for 140 training sessions. In 12 subsequent generalization tests under extinction conditions they classified with a high degree of accuracy six bilaterally symmetric and asymmetric visual patterns with which they had had no previous experience. The results indicate that pigeons can acquire the perceptual concept of symmetry, adding yet another to the list of concepts that these birds have been shown capable of mastering.