ENCODING OF SPATIAL INFORMATION IN IMAGES OF AN OUTDOOR SCENE BY PIGEONS AND HUMANS

Pigeons and adult humans searched for a 2-cm(2) unmarked goal in digit ized images of an outdoor scene presented on a touch-screen monitor. I n Experiment 1, the scene contained three landmarks near the goal and a visually rich background. Six training images presented the scene fr om different viewing directions and distances. Subsequent unreinforced tests in which landmark or background cues were removed or shifted re vealed that pigeons' search was controlled by both proximal landmarks and background cues, whereas humans relied only on the proximal landma rks. Pigeons' search accuracy dropped substantially when they were pre sented with novel views of the same scene, whereas humans showed perfe ct transfer to novel views. In Experiment 2, pigeons with previous out door experience and humans were trained with 28 views of an outdoor sc ene. Both pigeons and humans transferred well to novel views of the sc ene. This positive transfer suggests that, under some conditions, pige ons, like humans, may encode the three-dimensional spatial information in images of a scene.