Stable responding, which reflects the extent to which the animal has learned about the relation between stimuli and the likely location of food (the stimulus-food relation), was analyzed using data from the last five days of a condition. The analysis of stable responding used data from individual pigeons. Adaptation to a condition change (transition data) was analyzed using data from each session of a condition. Because individual-bird data from single sessions were sparse, in transition analyses we analyzed adaptation using data summed across all six pigeons.