ABSTRACT
Picture perception in birds was examined from four points of view: correlation, interaction, distortion, and transfer. The main question raised was whether they have the cognitive ability to relate pictures to the real world. Pigeons were found to see photographs but not line drawings as representations of real objects. Also, they did not see partly occluded figures as hidden objects, or occluding figures as hiding objects. These findings suggest that pigeons' cognition of line drawings and partly occluded objects differs from ours.
